You don't likely have timing chain issues. In order for it to jump a
tooth, the gears must be destroyed. Those chains are good for the life
of the engine and then some usually. One of my CJ steel sets is now on
it's 3rd engine incarnation with the exact slop as a new on measured in
degrees.

I would be suspecting something electrical like a cracked distributor
cap or even a burnt valve for backfiring.

Have you checked the amount of play in your chain? Stock new they have
about 15 deg of slop.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

griffin wrote:
>
> Ya I'm gonna do that in the spring ...after I replace the timing chain. I'm
> not a big fan of trying to drive it home with it backfiring all the time ;p
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:421BBDB6.24FB3D74@sympatico.ca...
> > I just did a 4 day bush run and gas station to gas station is 200 miles
> > so I get an easy check every trip. It was still 10.9L/100km which is
> > slightly better than 23 US mpg and I still have that beauty of a
> > Weber-Carter BBD in there... LOL!
> >
> > Just amazing what a $20.00 carb kit every 2 years does for them...
> >
> > Mike

 

You don't likely have timing chain issues. In order for it to jump a
tooth, the gears must be destroyed. Those chains are good for the life
of the engine and then some usually. One of my CJ steel sets is now on
it's 3rd engine incarnation with the exact slop as a new on measured in
degrees.

I would be suspecting something electrical like a cracked distributor
cap or even a burnt valve for backfiring.

Have you checked the amount of play in your chain? Stock new they have
about 15 deg of slop.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

griffin wrote:
>
> Ya I'm gonna do that in the spring ...after I replace the timing chain. I'm
> not a big fan of trying to drive it home with it backfiring all the time ;p
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:421BBDB6.24FB3D74@sympatico.ca...
> > I just did a 4 day bush run and gas station to gas station is 200 miles
> > so I get an easy check every trip. It was still 10.9L/100km which is
> > slightly better than 23 US mpg and I still have that beauty of a
> > Weber-Carter BBD in there... LOL!
> >
> > Just amazing what a $20.00 carb kit every 2 years does for them...
> >
> > Mike

 

Been through the following:

The entire electrical system. Then I had the local Jeep mechanic go through
it all and replace almost all the under-the-hood wiring. He managed to get
it running again after trying to retime it over and over but it only ran
when the engine was fully warmed up and it would backfire quite a bit if not
driven at the perfect RPM. Replaced about 15 wires, a couple of connectors,
the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
coils/sensors/etc.

The ignition system has been checked.
The fuel system has been checked.

The only thing left that hasn't been opened up is the TChain cover. When my
Jeep stalled during offroading, I'm thinking the dist cap was wet
(unbeknownst to me at the time). When I was getting pulled home, we tried to
pull-start it and it backfired something fierce. That *could* slip the
timing chain a tooth from the force, could it not? Oh well, when it's warm
out it's only like a 3-4 hour job to check that and it's the only thing I
can think of. If it is the TChain that has to be replaced, is there any way
to do it without taking the Rad out? Not sure it would survive.

--
griffin
'85 Jeep CJ-7
'97 Toyota Corolla SD

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:421C8FA4.9F571B74@sympatico.ca...
> You don't likely have timing chain issues. In order for it to jump a
> tooth, the gears must be destroyed. Those chains are good for the life
> of the engine and then some usually. One of my CJ steel sets is now on
> it's 3rd engine incarnation with the exact slop as a new on measured in
> degrees.
>
> I would be suspecting something electrical like a cracked distributor
> cap or even a burnt valve for backfiring.
>
> Have you checked the amount of play in your chain? Stock new they have
> about 15 deg of slop.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> griffin wrote:
> >
> > Ya I'm gonna do that in the spring ...after I replace the timing chain.
I'm
> > not a big fan of trying to drive it home with it backfiring all the time
;p
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:421BBDB6.24FB3D74@sympatico.ca...
> > > I just did a 4 day bush run and gas station to gas station is 200
miles
> > > so I get an easy check every trip. It was still 10.9L/100km which is
> > > slightly better than 23 US mpg and I still have that beauty of a
> > > Weber-Carter BBD in there... LOL!
> > >
> > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > >
> > > Mike

 

Been through the following:

The entire electrical system. Then I had the local Jeep mechanic go through
it all and replace almost all the under-the-hood wiring. He managed to get
it running again after trying to retime it over and over but it only ran
when the engine was fully warmed up and it would backfire quite a bit if not
driven at the perfect RPM. Replaced about 15 wires, a couple of connectors,
the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
coils/sensors/etc.

The ignition system has been checked.
The fuel system has been checked.

The only thing left that hasn't been opened up is the TChain cover. When my
Jeep stalled during offroading, I'm thinking the dist cap was wet
(unbeknownst to me at the time). When I was getting pulled home, we tried to
pull-start it and it backfired something fierce. That *could* slip the
timing chain a tooth from the force, could it not? Oh well, when it's warm
out it's only like a 3-4 hour job to check that and it's the only thing I
can think of. If it is the TChain that has to be replaced, is there any way
to do it without taking the Rad out? Not sure it would survive.

--
griffin
'85 Jeep CJ-7
'97 Toyota Corolla SD

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:421C8FA4.9F571B74@sympatico.ca...
> You don't likely have timing chain issues. In order for it to jump a
> tooth, the gears must be destroyed. Those chains are good for the life
> of the engine and then some usually. One of my CJ steel sets is now on
> it's 3rd engine incarnation with the exact slop as a new on measured in
> degrees.
>
> I would be suspecting something electrical like a cracked distributor
> cap or even a burnt valve for backfiring.
>
> Have you checked the amount of play in your chain? Stock new they have
> about 15 deg of slop.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> griffin wrote:
> >
> > Ya I'm gonna do that in the spring ...after I replace the timing chain.
I'm
> > not a big fan of trying to drive it home with it backfiring all the time
;p
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:421BBDB6.24FB3D74@sympatico.ca...
> > > I just did a 4 day bush run and gas station to gas station is 200
miles
> > > so I get an easy check every trip. It was still 10.9L/100km which is
> > > slightly better than 23 US mpg and I still have that beauty of a
> > > Weber-Carter BBD in there... LOL!
> > >
> > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > >
> > > Mike

 

Been through the following:

The entire electrical system. Then I had the local Jeep mechanic go through
it all and replace almost all the under-the-hood wiring. He managed to get
it running again after trying to retime it over and over but it only ran
when the engine was fully warmed up and it would backfire quite a bit if not
driven at the perfect RPM. Replaced about 15 wires, a couple of connectors,
the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
coils/sensors/etc.

The ignition system has been checked.
The fuel system has been checked.

The only thing left that hasn't been opened up is the TChain cover. When my
Jeep stalled during offroading, I'm thinking the dist cap was wet
(unbeknownst to me at the time). When I was getting pulled home, we tried to
pull-start it and it backfired something fierce. That *could* slip the
timing chain a tooth from the force, could it not? Oh well, when it's warm
out it's only like a 3-4 hour job to check that and it's the only thing I
can think of. If it is the TChain that has to be replaced, is there any way
to do it without taking the Rad out? Not sure it would survive.

--
griffin
'85 Jeep CJ-7
'97 Toyota Corolla SD

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:421C8FA4.9F571B74@sympatico.ca...
> You don't likely have timing chain issues. In order for it to jump a
> tooth, the gears must be destroyed. Those chains are good for the life
> of the engine and then some usually. One of my CJ steel sets is now on
> it's 3rd engine incarnation with the exact slop as a new on measured in
> degrees.
>
> I would be suspecting something electrical like a cracked distributor
> cap or even a burnt valve for backfiring.
>
> Have you checked the amount of play in your chain? Stock new they have
> about 15 deg of slop.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> griffin wrote:
> >
> > Ya I'm gonna do that in the spring ...after I replace the timing chain.
I'm
> > not a big fan of trying to drive it home with it backfiring all the time
;p
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:421BBDB6.24FB3D74@sympatico.ca...
> > > I just did a 4 day bush run and gas station to gas station is 200
miles
> > > so I get an easy check every trip. It was still 10.9L/100km which is
> > > slightly better than 23 US mpg and I still have that beauty of a
> > > Weber-Carter BBD in there... LOL!
> > >
> > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > >
> > > Mike

 

I think the 85 has a steel gear and chain set like my 86 has so jumping
is unlikely but possible.

One sneaky timing thing I don't see mentioned. Under the rotor is a
felt pad that needs to be soaked with oil. This lubs up the timing
advance plate and it's sleeve that sits on top of the distributor
shaft. If this goes dry, the timing will seem to change every time you
check it or it will stick with no timing advance allowed.

To test grab the rotor and see if you can turn it a bunch with a spring
loaded snap back. If not, that could be the trouble. It should be
really smooth and free in the movement.

To check the timing chain, you hand turn the engine with the distributor
cap off until you reach TDC on the timing mark. The rotor should be
pointing just before #1 or #6 if the chain is on the right tooth, way
off if jumped. You then turn it back the other way while watching the
rotor. The second the rotor moves, you look at the timing mark and that
gives you the 'slop' in the chain. 15 to 17 degrees is normal for new
to still good. Get higher and you could suspect a jumped chain.

Mike

griffin wrote:
>
> Been through the following:
>
> The entire electrical system. Then I had the local Jeep mechanic go through
> it all and replace almost all the under-the-hood wiring. He managed to get
> it running again after trying to retime it over and over but it only ran
> when the engine was fully warmed up and it would backfire quite a bit if not
> driven at the perfect RPM. Replaced about 15 wires, a couple of connectors,
> the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
> coils/sensors/etc.
>
> The ignition system has been checked.
> The fuel system has been checked.
>
> The only thing left that hasn't been opened up is the TChain cover. When my
> Jeep stalled during offroading, I'm thinking the dist cap was wet
> (unbeknownst to me at the time). When I was getting pulled home, we tried to
> pull-start it and it backfired something fierce. That *could* slip the
> timing chain a tooth from the force, could it not? Oh well, when it's warm
> out it's only like a 3-4 hour job to check that and it's the only thing I
> can think of. If it is the TChain that has to be replaced, is there any way
> to do it without taking the Rad out? Not sure it would survive.
>
> --
> griffin
> '85 Jeep CJ-7
> '97 Toyota Corolla SD
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:421C8FA4.9F571B74@sympatico.ca...
> > You don't likely have timing chain issues. In order for it to jump a
> > tooth, the gears must be destroyed. Those chains are good for the life
> > of the engine and then some usually. One of my CJ steel sets is now on
> > it's 3rd engine incarnation with the exact slop as a new on measured in
> > degrees.
> >
> > I would be suspecting something electrical like a cracked distributor
> > cap or even a burnt valve for backfiring.
> >
> > Have you checked the amount of play in your chain? Stock new they have
> > about 15 deg of slop.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > griffin wrote:
> > >
> > > Ya I'm gonna do that in the spring ...after I replace the timing chain.
> I'm
> > > not a big fan of trying to drive it home with it backfiring all the time
> ;p
> > >
> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > news:421BBDB6.24FB3D74@sympatico.ca...
> > > > I just did a 4 day bush run and gas station to gas station is 200
> miles
> > > > so I get an easy check every trip. It was still 10.9L/100km which is
> > > > slightly better than 23 US mpg and I still have that beauty of a
> > > > Weber-Carter BBD in there... LOL!
> > > >
> > > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > > >
> > > > Mike

 

I think the 85 has a steel gear and chain set like my 86 has so jumping
is unlikely but possible.

One sneaky timing thing I don't see mentioned. Under the rotor is a
felt pad that needs to be soaked with oil. This lubs up the timing
advance plate and it's sleeve that sits on top of the distributor
shaft. If this goes dry, the timing will seem to change every time you
check it or it will stick with no timing advance allowed.

To test grab the rotor and see if you can turn it a bunch with a spring
loaded snap back. If not, that could be the trouble. It should be
really smooth and free in the movement.

To check the timing chain, you hand turn the engine with the distributor
cap off until you reach TDC on the timing mark. The rotor should be
pointing just before #1 or #6 if the chain is on the right tooth, way
off if jumped. You then turn it back the other way while watching the
rotor. The second the rotor moves, you look at the timing mark and that
gives you the 'slop' in the chain. 15 to 17 degrees is normal for new
to still good. Get higher and you could suspect a jumped chain.

Mike

griffin wrote:
>
> Been through the following:
>
> The entire electrical system. Then I had the local Jeep mechanic go through
> it all and replace almost all the under-the-hood wiring. He managed to get
> it running again after trying to retime it over and over but it only ran
> when the engine was fully warmed up and it would backfire quite a bit if not
> driven at the perfect RPM. Replaced about 15 wires, a couple of connectors,
> the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
> coils/sensors/etc.
>
> The ignition system has been checked.
> The fuel system has been checked.
>
> The only thing left that hasn't been opened up is the TChain cover. When my
> Jeep stalled during offroading, I'm thinking the dist cap was wet
> (unbeknownst to me at the time). When I was getting pulled home, we tried to
> pull-start it and it backfired something fierce. That *could* slip the
> timing chain a tooth from the force, could it not? Oh well, when it's warm
> out it's only like a 3-4 hour job to check that and it's the only thing I
> can think of. If it is the TChain that has to be replaced, is there any way
> to do it without taking the Rad out? Not sure it would survive.
>
> --
> griffin
> '85 Jeep CJ-7
> '97 Toyota Corolla SD
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:421C8FA4.9F571B74@sympatico.ca...
> > You don't likely have timing chain issues. In order for it to jump a
> > tooth, the gears must be destroyed. Those chains are good for the life
> > of the engine and then some usually. One of my CJ steel sets is now on
> > it's 3rd engine incarnation with the exact slop as a new on measured in
> > degrees.
> >
> > I would be suspecting something electrical like a cracked distributor
> > cap or even a burnt valve for backfiring.
> >
> > Have you checked the amount of play in your chain? Stock new they have
> > about 15 deg of slop.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > griffin wrote:
> > >
> > > Ya I'm gonna do that in the spring ...after I replace the timing chain.
> I'm
> > > not a big fan of trying to drive it home with it backfiring all the time
> ;p
> > >
> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > news:421BBDB6.24FB3D74@sympatico.ca...
> > > > I just did a 4 day bush run and gas station to gas station is 200
> miles
> > > > so I get an easy check every trip. It was still 10.9L/100km which is
> > > > slightly better than 23 US mpg and I still have that beauty of a
> > > > Weber-Carter BBD in there... LOL!
> > > >
> > > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > > >
> > > > Mike

 

I think the 85 has a steel gear and chain set like my 86 has so jumping
is unlikely but possible.

One sneaky timing thing I don't see mentioned. Under the rotor is a
felt pad that needs to be soaked with oil. This lubs up the timing
advance plate and it's sleeve that sits on top of the distributor
shaft. If this goes dry, the timing will seem to change every time you
check it or it will stick with no timing advance allowed.

To test grab the rotor and see if you can turn it a bunch with a spring
loaded snap back. If not, that could be the trouble. It should be
really smooth and free in the movement.

To check the timing chain, you hand turn the engine with the distributor
cap off until you reach TDC on the timing mark. The rotor should be
pointing just before #1 or #6 if the chain is on the right tooth, way
off if jumped. You then turn it back the other way while watching the
rotor. The second the rotor moves, you look at the timing mark and that
gives you the 'slop' in the chain. 15 to 17 degrees is normal for new
to still good. Get higher and you could suspect a jumped chain.

Mike

griffin wrote:
>
> Been through the following:
>
> The entire electrical system. Then I had the local Jeep mechanic go through
> it all and replace almost all the under-the-hood wiring. He managed to get
> it running again after trying to retime it over and over but it only ran
> when the engine was fully warmed up and it would backfire quite a bit if not
> driven at the perfect RPM. Replaced about 15 wires, a couple of connectors,
> the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
> coils/sensors/etc.
>
> The ignition system has been checked.
> The fuel system has been checked.
>
> The only thing left that hasn't been opened up is the TChain cover. When my
> Jeep stalled during offroading, I'm thinking the dist cap was wet
> (unbeknownst to me at the time). When I was getting pulled home, we tried to
> pull-start it and it backfired something fierce. That *could* slip the
> timing chain a tooth from the force, could it not? Oh well, when it's warm
> out it's only like a 3-4 hour job to check that and it's the only thing I
> can think of. If it is the TChain that has to be replaced, is there any way
> to do it without taking the Rad out? Not sure it would survive.
>
> --
> griffin
> '85 Jeep CJ-7
> '97 Toyota Corolla SD
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:421C8FA4.9F571B74@sympatico.ca...
> > You don't likely have timing chain issues. In order for it to jump a
> > tooth, the gears must be destroyed. Those chains are good for the life
> > of the engine and then some usually. One of my CJ steel sets is now on
> > it's 3rd engine incarnation with the exact slop as a new on measured in
> > degrees.
> >
> > I would be suspecting something electrical like a cracked distributor
> > cap or even a burnt valve for backfiring.
> >
> > Have you checked the amount of play in your chain? Stock new they have
> > about 15 deg of slop.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > griffin wrote:
> > >
> > > Ya I'm gonna do that in the spring ...after I replace the timing chain.
> I'm
> > > not a big fan of trying to drive it home with it backfiring all the time
> ;p
> > >
> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > news:421BBDB6.24FB3D74@sympatico.ca...
> > > > I just did a 4 day bush run and gas station to gas station is 200
> miles
> > > > so I get an easy check every trip. It was still 10.9L/100km which is
> > > > slightly better than 23 US mpg and I still have that beauty of a
> > > > Weber-Carter BBD in there... LOL!
> > > >
> > > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > > >
> > > > Mike

 

Ya, we did the timing chain/rotor test and were about 22 deg off. We never
checked the actual TDC by pulling a plug, though and we HAD moved the
distributor slightly beforehand on a previous suggestion by someone so we
might have messed up the alignment. However, it's timed enough to start, so
we will double-check that in the spring again. Will also look into the rotor
pad ...thanks for that tip!

I'll let ya know what happens ...

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:421D1195.54318844@sympatico.ca...
> I think the 85 has a steel gear and chain set like my 86 has so jumping
> is unlikely but possible.
>
> One sneaky timing thing I don't see mentioned. Under the rotor is a
> felt pad that needs to be soaked with oil. This lubs up the timing
> advance plate and it's sleeve that sits on top of the distributor
> shaft. If this goes dry, the timing will seem to change every time you
> check it or it will stick with no timing advance allowed.
>
> To test grab the rotor and see if you can turn it a bunch with a spring
> loaded snap back. If not, that could be the trouble. It should be
> really smooth and free in the movement.
>
> To check the timing chain, you hand turn the engine with the distributor
> cap off until you reach TDC on the timing mark. The rotor should be
> pointing just before #1 or #6 if the chain is on the right tooth, way
> off if jumped. You then turn it back the other way while watching the
> rotor. The second the rotor moves, you look at the timing mark and that
> gives you the 'slop' in the chain. 15 to 17 degrees is normal for new
> to still good. Get higher and you could suspect a jumped chain.
>
> Mike
>
> griffin wrote:
> >
> > Been through the following:
> >
> > The entire electrical system. Then I had the local Jeep mechanic go
through
> > it all and replace almost all the under-the-hood wiring. He managed to
get
> > it running again after trying to retime it over and over but it only ran
> > when the engine was fully warmed up and it would backfire quite a bit if
not
> > driven at the perfect RPM. Replaced about 15 wires, a couple of
connectors,
> > the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
> > coils/sensors/etc.
> >
> > The ignition system has been checked.
> > The fuel system has been checked.
> >
> > The only thing left that hasn't been opened up is the TChain cover. When
my
> > Jeep stalled during offroading, I'm thinking the dist cap was wet
> > (unbeknownst to me at the time). When I was getting pulled home, we
tried to
> > pull-start it and it backfired something fierce. That *could* slip the
> > timing chain a tooth from the force, could it not? Oh well, when it's
warm
> > out it's only like a 3-4 hour job to check that and it's the only thing
I
> > can think of. If it is the TChain that has to be replaced, is there any
way
> > to do it without taking the Rad out? Not sure it would survive.
> >
> > --
> > griffin
> > '85 Jeep CJ-7
> > '97 Toyota Corolla SD
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:421C8FA4.9F571B74@sympatico.ca...
> > > You don't likely have timing chain issues. In order for it to jump a
> > > tooth, the gears must be destroyed. Those chains are good for the
life
> > > of the engine and then some usually. One of my CJ steel sets is now
on
> > > it's 3rd engine incarnation with the exact slop as a new on measured
in
> > > degrees.
> > >
> > > I would be suspecting something electrical like a cracked distributor
> > > cap or even a burnt valve for backfiring.
> > >
> > > Have you checked the amount of play in your chain? Stock new they
have
> > > about 15 deg of slop.
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> > > griffin wrote:
> > > >
> > > > Ya I'm gonna do that in the spring ...after I replace the timing
chain.
> > I'm
> > > > not a big fan of trying to drive it home with it backfiring all the
time
> > ;p
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:421BBDB6.24FB3D74@sympatico.ca...
> > > > > I just did a 4 day bush run and gas station to gas station is 200
> > miles
> > > > > so I get an easy check every trip. It was still 10.9L/100km which
is
> > > > > slightly better than 23 US mpg and I still have that beauty of a
> > > > > Weber-Carter BBD in there... LOL!
> > > > >
> > > > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > > > >
> > > > > Mike

 

Ya, we did the timing chain/rotor test and were about 22 deg off. We never
checked the actual TDC by pulling a plug, though and we HAD moved the
distributor slightly beforehand on a previous suggestion by someone so we
might have messed up the alignment. However, it's timed enough to start, so
we will double-check that in the spring again. Will also look into the rotor
pad ...thanks for that tip!

I'll let ya know what happens ...

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:421D1195.54318844@sympatico.ca...
> I think the 85 has a steel gear and chain set like my 86 has so jumping
> is unlikely but possible.
>
> One sneaky timing thing I don't see mentioned. Under the rotor is a
> felt pad that needs to be soaked with oil. This lubs up the timing
> advance plate and it's sleeve that sits on top of the distributor
> shaft. If this goes dry, the timing will seem to change every time you
> check it or it will stick with no timing advance allowed.
>
> To test grab the rotor and see if you can turn it a bunch with a spring
> loaded snap back. If not, that could be the trouble. It should be
> really smooth and free in the movement.
>
> To check the timing chain, you hand turn the engine with the distributor
> cap off until you reach TDC on the timing mark. The rotor should be
> pointing just before #1 or #6 if the chain is on the right tooth, way
> off if jumped. You then turn it back the other way while watching the
> rotor. The second the rotor moves, you look at the timing mark and that
> gives you the 'slop' in the chain. 15 to 17 degrees is normal for new
> to still good. Get higher and you could suspect a jumped chain.
>
> Mike
>
> griffin wrote:
> >
> > Been through the following:
> >
> > The entire electrical system. Then I had the local Jeep mechanic go
through
> > it all and replace almost all the under-the-hood wiring. He managed to
get
> > it running again after trying to retime it over and over but it only ran
> > when the engine was fully warmed up and it would backfire quite a bit if
not
> > driven at the perfect RPM. Replaced about 15 wires, a couple of
connectors,
> > the distributor cap/rotor/plugs/plug wires. Did diagnostics on all the
> > coils/sensors/etc.
> >
> > The ignition system has been checked.
> > The fuel system has been checked.
> >
> > The only thing left that hasn't been opened up is the TChain cover. When
my
> > Jeep stalled during offroading, I'm thinking the dist cap was wet
> > (unbeknownst to me at the time). When I was getting pulled home, we
tried to
> > pull-start it and it backfired something fierce. That *could* slip the
> > timing chain a tooth from the force, could it not? Oh well, when it's
warm
> > out it's only like a 3-4 hour job to check that and it's the only thing
I
> > can think of. If it is the TChain that has to be replaced, is there any
way
> > to do it without taking the Rad out? Not sure it would survive.
> >
> > --
> > griffin
> > '85 Jeep CJ-7
> > '97 Toyota Corolla SD
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:421C8FA4.9F571B74@sympatico.ca...
> > > You don't likely have timing chain issues. In order for it to jump a
> > > tooth, the gears must be destroyed. Those chains are good for the
life
> > > of the engine and then some usually. One of my CJ steel sets is now
on
> > > it's 3rd engine incarnation with the exact slop as a new on measured
in
> > > degrees.
> > >
> > > I would be suspecting something electrical like a cracked distributor
> > > cap or even a burnt valve for backfiring.
> > >
> > > Have you checked the amount of play in your chain? Stock new they
have
> > > about 15 deg of slop.
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > >
> > > griffin wrote:
> > > >
> > > > Ya I'm gonna do that in the spring ...after I replace the timing
chain.
> > I'm
> > > > not a big fan of trying to drive it home with it backfiring all the
time
> > ;p
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:421BBDB6.24FB3D74@sympatico.ca...
> > > > > I just did a 4 day bush run and gas station to gas station is 200
> > miles
> > > > > so I get an easy check every trip. It was still 10.9L/100km which
is
> > > > > slightly better than 23 US mpg and I still have that beauty of a
> > > > > Weber-Carter BBD in there... LOL!
> > > > >
> > > > > Just amazing what a $20.00 carb kit every 2 years does for them...
> > > > >
> > > > > Mike