Oil pump questions
05-02-2004, 04:38 PM
#31
Guest
Posts: n/a
Re: Oil pump questions
On Sun, 2 May 2004, Shaggie wrote:
> > What are you running hot and cold for pressure?
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
Moses Ludel says that oil pressure below 37psi @ 1600 rpm and below 13psi
@ 600 rpm is outside the limits, based on his experience with the 304.
YMMV.
> > What are you running hot and cold for pressure?
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
Moses Ludel says that oil pressure below 37psi @ 1600 rpm and below 13psi
@ 600 rpm is outside the limits, based on his experience with the 304.
YMMV.
05-02-2004, 04:38 PM
#32
Guest
Posts: n/a
Re: Oil pump questions
On Sun, 2 May 2004, Shaggie wrote:
> > What are you running hot and cold for pressure?
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
Moses Ludel says that oil pressure below 37psi @ 1600 rpm and below 13psi
@ 600 rpm is outside the limits, based on his experience with the 304.
YMMV.
> > What are you running hot and cold for pressure?
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
Moses Ludel says that oil pressure below 37psi @ 1600 rpm and below 13psi
@ 600 rpm is outside the limits, based on his experience with the 304.
YMMV.
05-02-2004, 04:38 PM
#33
Guest
Posts: n/a
Re: Oil pump questions
On Sun, 2 May 2004, Shaggie wrote:
> > What are you running hot and cold for pressure?
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
Moses Ludel says that oil pressure below 37psi @ 1600 rpm and below 13psi
@ 600 rpm is outside the limits, based on his experience with the 304.
YMMV.
> > What are you running hot and cold for pressure?
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
Moses Ludel says that oil pressure below 37psi @ 1600 rpm and below 13psi
@ 600 rpm is outside the limits, based on his experience with the 304.
YMMV.
05-02-2004, 07:31 PM
#34
Guest
Posts: n/a
Re: Oil pump questions
While you may be able to get pressure back up with a new hi-volume pump,
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
05-02-2004, 07:31 PM
#35
Guest
Posts: n/a
Re: Oil pump questions
While you may be able to get pressure back up with a new hi-volume pump,
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
05-02-2004, 07:31 PM
#36
Guest
Posts: n/a
Re: Oil pump questions
While you may be able to get pressure back up with a new hi-volume pump,
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
05-02-2004, 07:31 PM
#37
Guest
Posts: n/a
Re: Oil pump questions
While you may be able to get pressure back up with a new hi-volume pump,
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
that's not likely the source of your problem. Oil pressure is most likely
low because of excessive clearance in the crank and/or cam bearings. Higher
volume of oil will compensate for the increased clearance, but you'd be much
better off locating the problem and fixing that. Even with the restored oil
pressure you are at great risk of spinning a bearing if they're worn to that
degree. Catch it now and you can repair it in vehicle for the cost of the
shells and gaskets. Wait until one spins and it's R & R engine, grind
crank, resize rod (remove head to do that) etc. Pull the pan and pull a
couple of rod caps and the main caps furthest from the pump. Look for
obvious signs of wear, ie, the copper backing showing through the bearing
surface. If it's not apparent get some plasti-gage and check the actual
clearance. Cam bearings can't be checked easily, but are less likely to be
the problem. I would only suspect them if the crank checked out okay.
Steve
"Shaggie" <travist34@snotmail.com> wrote in message
news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> Mike Romain <romainm@sympatico.ca> wrote in
> news:4094EC8B.91F62890@sympatico.ca:
>
> > Shaggie wrote:
> >>
> >> "c" <c@me.org> wrote in
> >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> >>
> >> > Yup, a very common problem with electric oil pressure guages. I
> >> > keep an el cheapo mechanical guage around to test engines with.
> >> >
> >> > Chris
> >>
> >> The gauge I have now is a mechanical one with the high-pressure oil
> >> line running from the "sender" to the gauge. It is a cheap gauge so
> >> I suppose the gauge itself could be bad.
> >
> > What are you running hot and cold for pressure?
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> When I first start it up and it's cold I can hit 60psi but at idle when
> it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> when it's hot it only hits about 16psi or so. Sound pretty bad?
>
> --
>
> I can hammer it back into shape later...
> :wq!
05-02-2004, 07:56 PM
#38
Guest
Posts: n/a
Re: Oil pump questions
I will have to agree with Steve.
Even just putting a set of 'stock' for your engine main and connecting
rod bearings back in will jump the pressure way back up. If you
plastigauge it, you can get 0.001 or 0.002 over to make it tight
again...
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Steve G wrote:
>
> While you may be able to get pressure back up with a new hi-volume pump,
> that's not likely the source of your problem. Oil pressure is most likely
> low because of excessive clearance in the crank and/or cam bearings. Higher
> volume of oil will compensate for the increased clearance, but you'd be much
> better off locating the problem and fixing that. Even with the restored oil
> pressure you are at great risk of spinning a bearing if they're worn to that
> degree. Catch it now and you can repair it in vehicle for the cost of the
> shells and gaskets. Wait until one spins and it's R & R engine, grind
> crank, resize rod (remove head to do that) etc. Pull the pan and pull a
> couple of rod caps and the main caps furthest from the pump. Look for
> obvious signs of wear, ie, the copper backing showing through the bearing
> surface. If it's not apparent get some plasti-gage and check the actual
> clearance. Cam bearings can't be checked easily, but are less likely to be
> the problem. I would only suspect them if the crank checked out okay.
> Steve
>
> "Shaggie" <travist34@snotmail.com> wrote in message
> news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> > Mike Romain <romainm@sympatico.ca> wrote in
> > news:4094EC8B.91F62890@sympatico.ca:
> >
> > > Shaggie wrote:
> > >>
> > >> "c" <c@me.org> wrote in
> > >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> > >>
> > >> > Yup, a very common problem with electric oil pressure guages. I
> > >> > keep an el cheapo mechanical guage around to test engines with.
> > >> >
> > >> > Chris
> > >>
> > >> The gauge I have now is a mechanical one with the high-pressure oil
> > >> line running from the "sender" to the gauge. It is a cheap gauge so
> > >> I suppose the gauge itself could be bad.
> > >
> > > What are you running hot and cold for pressure?
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> >
> > When I first start it up and it's cold I can hit 60psi but at idle when
> > it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> > when it's hot it only hits about 16psi or so. Sound pretty bad?
> >
> > --
> >
> > I can hammer it back into shape later...
> > :wq!
Even just putting a set of 'stock' for your engine main and connecting
rod bearings back in will jump the pressure way back up. If you
plastigauge it, you can get 0.001 or 0.002 over to make it tight
again...
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Steve G wrote:
>
> While you may be able to get pressure back up with a new hi-volume pump,
> that's not likely the source of your problem. Oil pressure is most likely
> low because of excessive clearance in the crank and/or cam bearings. Higher
> volume of oil will compensate for the increased clearance, but you'd be much
> better off locating the problem and fixing that. Even with the restored oil
> pressure you are at great risk of spinning a bearing if they're worn to that
> degree. Catch it now and you can repair it in vehicle for the cost of the
> shells and gaskets. Wait until one spins and it's R & R engine, grind
> crank, resize rod (remove head to do that) etc. Pull the pan and pull a
> couple of rod caps and the main caps furthest from the pump. Look for
> obvious signs of wear, ie, the copper backing showing through the bearing
> surface. If it's not apparent get some plasti-gage and check the actual
> clearance. Cam bearings can't be checked easily, but are less likely to be
> the problem. I would only suspect them if the crank checked out okay.
> Steve
>
> "Shaggie" <travist34@snotmail.com> wrote in message
> news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> > Mike Romain <romainm@sympatico.ca> wrote in
> > news:4094EC8B.91F62890@sympatico.ca:
> >
> > > Shaggie wrote:
> > >>
> > >> "c" <c@me.org> wrote in
> > >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> > >>
> > >> > Yup, a very common problem with electric oil pressure guages. I
> > >> > keep an el cheapo mechanical guage around to test engines with.
> > >> >
> > >> > Chris
> > >>
> > >> The gauge I have now is a mechanical one with the high-pressure oil
> > >> line running from the "sender" to the gauge. It is a cheap gauge so
> > >> I suppose the gauge itself could be bad.
> > >
> > > What are you running hot and cold for pressure?
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> >
> > When I first start it up and it's cold I can hit 60psi but at idle when
> > it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> > when it's hot it only hits about 16psi or so. Sound pretty bad?
> >
> > --
> >
> > I can hammer it back into shape later...
> > :wq!
05-02-2004, 07:56 PM
#39
Guest
Posts: n/a
Re: Oil pump questions
I will have to agree with Steve.
Even just putting a set of 'stock' for your engine main and connecting
rod bearings back in will jump the pressure way back up. If you
plastigauge it, you can get 0.001 or 0.002 over to make it tight
again...
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Steve G wrote:
>
> While you may be able to get pressure back up with a new hi-volume pump,
> that's not likely the source of your problem. Oil pressure is most likely
> low because of excessive clearance in the crank and/or cam bearings. Higher
> volume of oil will compensate for the increased clearance, but you'd be much
> better off locating the problem and fixing that. Even with the restored oil
> pressure you are at great risk of spinning a bearing if they're worn to that
> degree. Catch it now and you can repair it in vehicle for the cost of the
> shells and gaskets. Wait until one spins and it's R & R engine, grind
> crank, resize rod (remove head to do that) etc. Pull the pan and pull a
> couple of rod caps and the main caps furthest from the pump. Look for
> obvious signs of wear, ie, the copper backing showing through the bearing
> surface. If it's not apparent get some plasti-gage and check the actual
> clearance. Cam bearings can't be checked easily, but are less likely to be
> the problem. I would only suspect them if the crank checked out okay.
> Steve
>
> "Shaggie" <travist34@snotmail.com> wrote in message
> news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> > Mike Romain <romainm@sympatico.ca> wrote in
> > news:4094EC8B.91F62890@sympatico.ca:
> >
> > > Shaggie wrote:
> > >>
> > >> "c" <c@me.org> wrote in
> > >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> > >>
> > >> > Yup, a very common problem with electric oil pressure guages. I
> > >> > keep an el cheapo mechanical guage around to test engines with.
> > >> >
> > >> > Chris
> > >>
> > >> The gauge I have now is a mechanical one with the high-pressure oil
> > >> line running from the "sender" to the gauge. It is a cheap gauge so
> > >> I suppose the gauge itself could be bad.
> > >
> > > What are you running hot and cold for pressure?
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> >
> > When I first start it up and it's cold I can hit 60psi but at idle when
> > it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> > when it's hot it only hits about 16psi or so. Sound pretty bad?
> >
> > --
> >
> > I can hammer it back into shape later...
> > :wq!
Even just putting a set of 'stock' for your engine main and connecting
rod bearings back in will jump the pressure way back up. If you
plastigauge it, you can get 0.001 or 0.002 over to make it tight
again...
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Steve G wrote:
>
> While you may be able to get pressure back up with a new hi-volume pump,
> that's not likely the source of your problem. Oil pressure is most likely
> low because of excessive clearance in the crank and/or cam bearings. Higher
> volume of oil will compensate for the increased clearance, but you'd be much
> better off locating the problem and fixing that. Even with the restored oil
> pressure you are at great risk of spinning a bearing if they're worn to that
> degree. Catch it now and you can repair it in vehicle for the cost of the
> shells and gaskets. Wait until one spins and it's R & R engine, grind
> crank, resize rod (remove head to do that) etc. Pull the pan and pull a
> couple of rod caps and the main caps furthest from the pump. Look for
> obvious signs of wear, ie, the copper backing showing through the bearing
> surface. If it's not apparent get some plasti-gage and check the actual
> clearance. Cam bearings can't be checked easily, but are less likely to be
> the problem. I would only suspect them if the crank checked out okay.
> Steve
>
> "Shaggie" <travist34@snotmail.com> wrote in message
> news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> > Mike Romain <romainm@sympatico.ca> wrote in
> > news:4094EC8B.91F62890@sympatico.ca:
> >
> > > Shaggie wrote:
> > >>
> > >> "c" <c@me.org> wrote in
> > >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> > >>
> > >> > Yup, a very common problem with electric oil pressure guages. I
> > >> > keep an el cheapo mechanical guage around to test engines with.
> > >> >
> > >> > Chris
> > >>
> > >> The gauge I have now is a mechanical one with the high-pressure oil
> > >> line running from the "sender" to the gauge. It is a cheap gauge so
> > >> I suppose the gauge itself could be bad.
> > >
> > > What are you running hot and cold for pressure?
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> >
> > When I first start it up and it's cold I can hit 60psi but at idle when
> > it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> > when it's hot it only hits about 16psi or so. Sound pretty bad?
> >
> > --
> >
> > I can hammer it back into shape later...
> > :wq!
05-02-2004, 07:56 PM
#40
Guest
Posts: n/a
Re: Oil pump questions
I will have to agree with Steve.
Even just putting a set of 'stock' for your engine main and connecting
rod bearings back in will jump the pressure way back up. If you
plastigauge it, you can get 0.001 or 0.002 over to make it tight
again...
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Steve G wrote:
>
> While you may be able to get pressure back up with a new hi-volume pump,
> that's not likely the source of your problem. Oil pressure is most likely
> low because of excessive clearance in the crank and/or cam bearings. Higher
> volume of oil will compensate for the increased clearance, but you'd be much
> better off locating the problem and fixing that. Even with the restored oil
> pressure you are at great risk of spinning a bearing if they're worn to that
> degree. Catch it now and you can repair it in vehicle for the cost of the
> shells and gaskets. Wait until one spins and it's R & R engine, grind
> crank, resize rod (remove head to do that) etc. Pull the pan and pull a
> couple of rod caps and the main caps furthest from the pump. Look for
> obvious signs of wear, ie, the copper backing showing through the bearing
> surface. If it's not apparent get some plasti-gage and check the actual
> clearance. Cam bearings can't be checked easily, but are less likely to be
> the problem. I would only suspect them if the crank checked out okay.
> Steve
>
> "Shaggie" <travist34@snotmail.com> wrote in message
> news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> > Mike Romain <romainm@sympatico.ca> wrote in
> > news:4094EC8B.91F62890@sympatico.ca:
> >
> > > Shaggie wrote:
> > >>
> > >> "c" <c@me.org> wrote in
> > >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> > >>
> > >> > Yup, a very common problem with electric oil pressure guages. I
> > >> > keep an el cheapo mechanical guage around to test engines with.
> > >> >
> > >> > Chris
> > >>
> > >> The gauge I have now is a mechanical one with the high-pressure oil
> > >> line running from the "sender" to the gauge. It is a cheap gauge so
> > >> I suppose the gauge itself could be bad.
> > >
> > > What are you running hot and cold for pressure?
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> >
> > When I first start it up and it's cold I can hit 60psi but at idle when
> > it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> > when it's hot it only hits about 16psi or so. Sound pretty bad?
> >
> > --
> >
> > I can hammer it back into shape later...
> > :wq!
Even just putting a set of 'stock' for your engine main and connecting
rod bearings back in will jump the pressure way back up. If you
plastigauge it, you can get 0.001 or 0.002 over to make it tight
again...
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Steve G wrote:
>
> While you may be able to get pressure back up with a new hi-volume pump,
> that's not likely the source of your problem. Oil pressure is most likely
> low because of excessive clearance in the crank and/or cam bearings. Higher
> volume of oil will compensate for the increased clearance, but you'd be much
> better off locating the problem and fixing that. Even with the restored oil
> pressure you are at great risk of spinning a bearing if they're worn to that
> degree. Catch it now and you can repair it in vehicle for the cost of the
> shells and gaskets. Wait until one spins and it's R & R engine, grind
> crank, resize rod (remove head to do that) etc. Pull the pan and pull a
> couple of rod caps and the main caps furthest from the pump. Look for
> obvious signs of wear, ie, the copper backing showing through the bearing
> surface. If it's not apparent get some plasti-gage and check the actual
> clearance. Cam bearings can't be checked easily, but are less likely to be
> the problem. I would only suspect them if the crank checked out okay.
> Steve
>
> "Shaggie" <travist34@snotmail.com> wrote in message
> news:c73a77$h9nm7$1@ID-163201.news.uni-berlin.de...
> > Mike Romain <romainm@sympatico.ca> wrote in
> > news:4094EC8B.91F62890@sympatico.ca:
> >
> > > Shaggie wrote:
> > >>
> > >> "c" <c@me.org> wrote in
> > >> news:KL%kc.13933$u_4.5819@twister.rdc-kc.rr.com:
> > >>
> > >> > Yup, a very common problem with electric oil pressure guages. I
> > >> > keep an el cheapo mechanical guage around to test engines with.
> > >> >
> > >> > Chris
> > >>
> > >> The gauge I have now is a mechanical one with the high-pressure oil
> > >> line running from the "sender" to the gauge. It is a cheap gauge so
> > >> I suppose the gauge itself could be bad.
> > >
> > > What are you running hot and cold for pressure?
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> >
> > When I first start it up and it's cold I can hit 60psi but at idle when
> > it's hot (210 degrees or so) it's down around 8psi. Even at 50mph or so
> > when it's hot it only hits about 16psi or so. Sound pretty bad?
> >
> > --
> >
> > I can hammer it back into shape later...
> > :wq!