preventative maintenance?
 

Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles). I
am wondering if it would be worth the cost of a new oil pump while I have
it open? My oil pressure seems about right with what others have out of
the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
timing chain? Thanks guys!

Re: preventative maintenance?
 

Contrary to popular belief, the oil pump is seldom responsible for low oil
pressure and they typically outlast the rest of the engine. If you've got
a case of "whileimatits" what I would check is main and rod brgs. Worn
bearings are the most common cause of low oil pressure and are a wear item
by nature of their design.

If you can rock the crank any appreciable amount, more than a couple of
degrees without moving the cam shaft or the chain deflects more than about
1/4" I'd replace it. In fact, if the upper gear is a nylon sprocket and it
hadn't been replace in a while, I'd probably do them all even if the chain
looked tight. The sprocket and chain can look nice and tight until all of
the teeth come off the sprocket suddenly and it's all over.
Steve
"Sleestak" <here@there.com> wrote in message
news:10aaape9uc91jf5@corp.supernews.com...
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles).
I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!

Re: preventative maintenance?
 

Contrary to popular belief, the oil pump is seldom responsible for low oil
pressure and they typically outlast the rest of the engine. If you've got
a case of "whileimatits" what I would check is main and rod brgs. Worn
bearings are the most common cause of low oil pressure and are a wear item
by nature of their design.

If you can rock the crank any appreciable amount, more than a couple of
degrees without moving the cam shaft or the chain deflects more than about
1/4" I'd replace it. In fact, if the upper gear is a nylon sprocket and it
hadn't been replace in a while, I'd probably do them all even if the chain
looked tight. The sprocket and chain can look nice and tight until all of
the teeth come off the sprocket suddenly and it's all over.
Steve
"Sleestak" <here@there.com> wrote in message
news:10aaape9uc91jf5@corp.supernews.com...
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles).
I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!

Re: preventative maintenance?
 

Contrary to popular belief, the oil pump is seldom responsible for low oil
pressure and they typically outlast the rest of the engine. If you've got
a case of "whileimatits" what I would check is main and rod brgs. Worn
bearings are the most common cause of low oil pressure and are a wear item
by nature of their design.

If you can rock the crank any appreciable amount, more than a couple of
degrees without moving the cam shaft or the chain deflects more than about
1/4" I'd replace it. In fact, if the upper gear is a nylon sprocket and it
hadn't been replace in a while, I'd probably do them all even if the chain
looked tight. The sprocket and chain can look nice and tight until all of
the teeth come off the sprocket suddenly and it's all over.
Steve
"Sleestak" <here@there.com> wrote in message
news:10aaape9uc91jf5@corp.supernews.com...
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles).
I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!

Re: preventative maintenance?
 

Contrary to popular belief, the oil pump is seldom responsible for low oil
pressure and they typically outlast the rest of the engine. If you've got
a case of "whileimatits" what I would check is main and rod brgs. Worn
bearings are the most common cause of low oil pressure and are a wear item
by nature of their design.

If you can rock the crank any appreciable amount, more than a couple of
degrees without moving the cam shaft or the chain deflects more than about
1/4" I'd replace it. In fact, if the upper gear is a nylon sprocket and it
hadn't been replace in a while, I'd probably do them all even if the chain
looked tight. The sprocket and chain can look nice and tight until all of
the teeth come off the sprocket suddenly and it's all over.
Steve
"Sleestak" <here@there.com> wrote in message
news:10aaape9uc91jf5@corp.supernews.com...
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles).
I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!

Re: preventative maintenance?
 

20 psi at idle hot is excellent for that engine.

The timing chain gears in CJ's are 'real' gears and are steel, unlike
the YJ versions.

New they have close to 15 degrees movement before the cam turns.

That means turn the crank to the timing mark and look at the rotor.
Then turn the crank back watching the rotor and see how many degrees it
moves before the rotor starts moving again.

They look and feel sloppy. They have no tensioner or anything.

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

Sleestak wrote:
>
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles). I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!

Re: preventative maintenance?
 

20 psi at idle hot is excellent for that engine.

The timing chain gears in CJ's are 'real' gears and are steel, unlike
the YJ versions.

New they have close to 15 degrees movement before the cam turns.

That means turn the crank to the timing mark and look at the rotor.
Then turn the crank back watching the rotor and see how many degrees it
moves before the rotor starts moving again.

They look and feel sloppy. They have no tensioner or anything.

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

Sleestak wrote:
>
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles). I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!

Re: preventative maintenance?
 

20 psi at idle hot is excellent for that engine.

The timing chain gears in CJ's are 'real' gears and are steel, unlike
the YJ versions.

New they have close to 15 degrees movement before the cam turns.

That means turn the crank to the timing mark and look at the rotor.
Then turn the crank back watching the rotor and see how many degrees it
moves before the rotor starts moving again.

They look and feel sloppy. They have no tensioner or anything.

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

Sleestak wrote:
>
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles). I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!

Re: preventative maintenance?
 

20 psi at idle hot is excellent for that engine.

The timing chain gears in CJ's are 'real' gears and are steel, unlike
the YJ versions.

New they have close to 15 degrees movement before the cam turns.

That means turn the crank to the timing mark and look at the rotor.
Then turn the crank back watching the rotor and see how many degrees it
moves before the rotor starts moving again.

They look and feel sloppy. They have no tensioner or anything.

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

Sleestak wrote:
>
> Ok, I have the oil pan off of my jeep again (86 cj7, 258, 88,000 miles). I
> am wondering if it would be worth the cost of a new oil pump while I have
> it open? My oil pressure seems about right with what others have out of
> the 258 -- 20 pounds idle, warm. Also, how much, is too much slack in the
> timing chain? Thanks guys!