Help ! 91" Timing chain replacement .

[DJM/78]

I am replacing the timing chain on a 91" 2.5 motor with the tensioner . Since its been making a loud noise I thought was coming from the cylinder head . I figured I would go ahead and just purchase an entire gear and chain set ,

with the tensioner from NAPA . My question is why was there a difference in the 92" 2.5 being that it has no tensioner , can I use the new style gear set without the tensioner or do I need the old style gear set ?

 

I don't know much about the 2.5 but in most of the things I've been reading I don't see very much on either motor . Are there any other things I should replace wile I'm in there ? Water pump , timing cover gasket ?

 

Thanks for the help !

[Geonovast]

92' has a tensioner...

[DJM/78]

92' has a tensioner...

 

See now the parts store and my Hayne's manual said that there is a tensioner on the 91" but not the 92" different part# from NAPA as well , In the book its installed different

as well from the 92" . Or is it all the same thing , I can not get any info on the difference on timing chains from 91-92 on the 2.5 L .

At least in the book there is no tensioner ?

[jimoshel]

When in doubt, just find a local MJ nut,er, enthusiast and just give the truck to me, er, him. Let him worry about it. Without knowing for sure or having a definite reason to change, I'd just stay with the current set up.

[DJM/78]

When in doubt, just find a local MJ nut,er, enthusiast and just give the truck to me, er, him. Let him worry about it. Without knowing for sure or having a definite reason to change, I'd just stay with the current set up.

 

Thanks Jim and Geonovast for the input , I think this dammed Hayne's manual has me confused , which isn't hard for me considering my ADD .... :drool:

 

Jim , your not getting another one that easy ( this time ) ... :clapping:

[jimoshel]

Shucks. It was worth a try. :D Haynes, and Chilton are OK for a general reference but they're just not good for finer details.

[Geonovast]

Well, I've never had a 92, but I did have a 93 2.5, and that DOES have a tensioner.

 

Whoever wrote the book probably go mixed information, because the 4.0 does not have a tensioner.

[kastein]

Haynes info ranges from wildly inaccurate to a brilliant work of fiction :(

 

My parts catalog for the 91-93 model year range says there are no differences in the 91-93 year range 2.5L timing chain/cover/associated parts.

[DJM/78]

Well, I've never had a 92, but I did have a 93 2.5, and that DOES have a tensioner.

 

Whoever wrote the book probably go mixed information, because the 4.0 does not have a tensioner.

 

Your right , its the Hayne's manual ... :shake: , I checked NAPA and they said it was the same part# as the 92" . i Also ordered a timing chain gasket set and seal from them as well .

Thanks for the help , thats why I asked you guys , I knew something was wrong .

[bigd44889]

these guy are so smart :brows:

when in dought ask the obsessed :cheers:

[DJM/78]

these guy are so smart :brows:

when in dought ask the obsessed :cheers:

 

I just read the book again just to make sure my ADD hadn't taken over through my reading and yes , it states that the 92" chain cover and timing chain are different from the 91". It also shows no need to install a gasket on the cover ( 92" only ) ..... :rotf:

 

I knew something was up when I say my 92" had a gasket . :hmm:

[bigd44889]

if you do a serch

at one time there was a link on here to a down loadable service manual for the 2.5

i'm leaving for work when i get home i will pull it out

i burned it to disk

see what it say's the guys on here arn't quite as good with 2.5 as thay are with 4.0

we are the oddballs runing 2.5's lol :cheers:

[Eagle]

The deal is that the 2.5L uses the same timing chain and gears as the 4.0L, but the 2.5L has a slightly lower deck (and cam) height. Which means that the 4.0L timing chain is just long enough to have slop in it when used in a 2.5L. Rather than use two different timing sets, AMC simply decided to add a tensioner to the 2.5L.

[DJM/78]

The deal is that the 2.5L uses the same timing chain and gears as the 4.0L, but the 2.5L has a slightly lower deck (and cam) height. Which means that the 4.0L timing chain is just long enough to have slop in it when used in a 2.5L. Rather than use two different timing sets, AMC simply decided to add a tensioner to the 2.5L.

 

Thank you Eagle , short and simple . Its amazing how much time I put into thinking about that .