I have decided to replace the lifters in my 87 Cherokee 4.0. I did a compression test today and all cylinders were between 135 ish and 145 ish. ( pretty good for a motor with 250,000 miles).

my question, can i put new push rods, rockers and all the other " bolt on" valve train parts when I drop in new lifters?

 

I assume you're looking for a response from the known engine guy(s), but yes, that is my understanding. You have a green light to replace all those components. The only restriction would be new cam with old lifters.

 

Why are you thinking about replacing the lifters?

 

A couple of them are clicking and clacking like two monkeys beating on a rock with a couple of sticks.

 

Is this noise something that is constant throughout the entire temperature range? Have you had the valve cover off to firmly diagnose the noise as failed lifters? (Loss of preload, excessive material in oil, pressure chambers no longer holding oil)

I'd hate to hear that you swapped in a set of "new" lifters just have them fail catastrophically. Flat tappet roulette is what we call it. I do have a set of OEM lifters that have been cleaned and resurfaced sitting in my garage.

 

I am sure it is valve click. I have alot of experience with old VW's, with the adjustable rockers and solid lifters. I learned to recognize the sound of a loose rocker. This is lifter click. From # 4 and sometimes # 3 cylinder. If it was an old VW, I would just break out the feeler gauge, a flat screwdriver and a 12mm wrench have it quiet again in about 10 minutes, but not such luck with these "modern" motors😛

 

I dont want to come across as a smart ***. But why, and almost everywhere I search, there is such a skepticism about bad lifters and how new ones can be a bad idea? What am I missing? I am asking with open arms and open ears.

(more info, I have recently had the oil pan off. No issues in there. I gave each rod a "pull push yank twist by hand test" and no issues there. My compression is 135+ to 145+ across the board. The clack is most prevelant at idle after a period of constant rpm, like just regular driving.)

 

The issue is cam wear. Your lifters and cam lobes have "mated" together. The lifters get a bit concave and the lobes round over. Replacing just the lifters can result in premature wear and even failure due to the rounded lobe. I know lot's of folks just swap the lifters anyway because swapping the cam is pain.

In theory, you could remove the lifters (mark where they go), and give them a good cleaning.

 

When you're at it, it's totally cool to upgrade other valve train parts like push rods and rockers, especially if they've seen their fair share of wear and tear. It's like giving your ol' Cherokee a fresh set of muscles to flex! Just make sure the new parts are compatible with your setup, and you'll be revving that engine with style.

 

Just to wrap this thread up. I finished up with new lifters, new rockers, new push rods, new pivots and new bridges. I used Melling brand, made in the USA! I used Melling assembly lube also.

It is "click clack" free now. So, I guess they all DON'T sound like that.

The only issue I had was I broke the fuel quick fitting at the pressure regulator ,and, I have either not got the manifold bolts tight enough or I tweaked the manifold to exhaust pipe connector. I have a slight exhaust leak. I did use a floor jack under the exhaust pipe to lift it and support it, and I yanked on it pretty good to get the manifold over the two end bolts, so Im betting that is it.

 

Yep, the "fun" never stops.

That EGR pipe is my Kryptonite. When I swapped out my exhaust manifold, I could not get it out of the intake manifold. I was so worried that I'd crush it. I had to channel my inner Eddie Hall the get things back in place. Worst nightmare, I had an intake leak and had to do it over. Still, a happy ending after all.

 

What was the issue with the lifter?

 

[QUOTE=Randy Bobani;3701245]What was the issue with the lifter?[/QUOTE

They were 35 years old and had 260,000 miles on them. They would not hold pressure and my rockers clacked like a diesel motor.

 

Since He has been following along in this thread, I think the tone of Randy Bobani's question was more towards - Did you find any obvious failures with the lifters after an autopsy?

 

[QUOTE=oldnslow;3701255]I wouldn't know what a bad lifter would look like. The rockers seemed to have about a .003 deep wear pattern from the valve stem. The pivot point in the rocker had a very slight wear ridge also. So, I'm sure the replacement was not in vane. They needed it. As far as lifters go, still all quiet.