Replacing hydraulic lifters is a 4.0 liter Jeep

[Cornbread]

After 193,000 miles, head gasket will need to be replaced in my 1999 Jeep Cherokee. While the head is off, I would like to replace the hydraullic lifters. I understand that a new cam and old lifters is a no-no. How do y`all feel about an old cam and new lifters?

The originals are OK, just the characteristic occasional clatter at startup.

 

[Steve S]

I would take a chance and leave them alone.Do an auto R/X occasional clatter at startup wouldn't worry me . I am not familiar with the 4.0 it is a straight 6? isn't there a cover in the side of the block like a Ford 6 cyl?

 

[rg200amp]

The 4.0 is a bulletproof motor. I would leave them alone.

 

[Chris142]

Originally Posted By: Steve S
isn't there a cover in the side of the block like a Ford 6 cyl?
No. The head must come off to remove the lifters.

Why does the OP want to replace them? I would not be suprized if one or more cam lobes show some wear with that milage. Putting a new lifter on that lobe will kill it fast.

I'd either leave it alone or replace the cam, lifters, timing chain and gears.

 

[Steve S]

Another good reason not to buy a Chrysler product

 

[-Clayton-]

Originally Posted By: Steve S
Another good reason not to buy a Chrysler product


The brand bashing around here lately is starting to get a little stale.

 

[MNgopher]

If you don't like the engine design, blame AMC, not Chrysler, considering the engines origins. Quite frankly, the 4.0l engine was a reason to buy a Chrysler product.

 

[rg200amp]

Yep, the 4.0 was one of the best engines made. My 97 Jeep really rusted away around the enigne.

The 4.0 is up there with fords modular in quality and reliability IMHO

 

[GMBoy]

Originally Posted By: -Clayton-
Originally Posted By: Steve S
Another good reason not to buy a Chrysler product


The brand bashing around here lately is starting to get a little stale.



X2

 

[Challenger71]

To the OP, I would'nt worry about startup clatter if that is all you are experiencing with it. Now if the clatter remained well after startup then I'd worry about a potential collapsed lifter(s). If the cam lobes look good then I would'nt fix what isnt broken in that aspect. You could upgrade your rockers to roller-rockers from yella terra: http://www.quadratec.com/products/51103_500.htm
This is what I did, much smoother at idle, across the rpm band.

Clayton+GMBoy, all the more reason to ignore the offending poster.

 

[Donald]

I agree with an Auto-Rx treatment and to leave the lifters alone. Auto-Rx should clean up the lifters if they are gummed up.

 

[meep]

Originally Posted By: Steve S
Another good reason not to buy a Chrysler product


Clearly you've no experience with this motor. Perhaps one of the most overbuilt and long-lasting motors ever built. Easily makes the top 10.

 

[Chris142]

Originally Posted By: MNgopher
Quite frankly, the 4.0l engine was a reason to buy a Chrysler product.
Pretty much my only reason

Oh I'd take a 225,318,360,383 or 440 too.

 

[Zaedock]

I would replace the oil pump before messing with the lifters. At 193K, the stock pump is beyond it's life expectency.

Throw $70 at a pump, one piece oil pan gasket, & rear main seal (while you're there) and I'll bet your clatter will subside.

 

[Zaedock]

Originally Posted By: Chris142
Originally Posted By: MNgopher
Quite frankly, the 4.0l engine was a reason to buy a Chrysler product.
Pretty much my only reason

Oh I'd take a 225,318,360,383 or 440 too.


Ironic too, that when the 4.0L came out, it had more power than most V8's. Not bad for a tractor.

 

[J_Myler]

Originally Posted By: GMBoy
Originally Posted By: -Clayton-
Originally Posted By: Steve S
Another good reason not to buy a Chrysler product


The brand bashing around here lately is starting to get a little stale.



X2


Make that Three

 

[Gary Allan]

Yep ..the 4.0 is very hard to kill. Not an exciting engine, but the really good ones rarely are. Start up rattle is usually a filter issue...

If you get roller rockers from Yella Terra ..get 1.7:1 ratio instead of the 1.6. That will give you, almost exactly, the same lift as the discontinued .450 cam. I bought Mopar rr's (Hesco made them). I think it's about $75-$100/hp ..but does appear to smooth out the crude and the rude to a more refined feeling. Then again, at $600-$700 ..you're going to feel something for the wallet flattening.

In case you're interested ..and decide to use a high volume oil pump, Napa carries it ..as do others.

 

[Eddie]

If money is an issue, he could perform a leakdown test on the origional lifters!! TADA

 

[JackFish]

It would take about 2 minutes to swap out those lifters, no reason not to since the head is coming off anyways.
Yes new lifters on an old cam is OK.
You'll want to clean the pistons tops.

 

[mechtech2]

New lifters are a great idea.
They have the nice new convex mating surface that rotates them and adds valve lift. [they also act as a mini cam]
A set of pushrods is a great idea, also. Their tips get worn and will click. Surprisingly cheap for a set. And rockers can not have wear grooves - they will stick and click.
I'd lube everything well with engine assembly lube, and overfill the crankcase with 1/2 qt extra. Be prepared for scary clacking when you start it up!