Rickster70

They don't seem to look too bad. All done now. Not bad...3 hours start to finish for my first time. Most of that is cleaning was spent degreasing the cover and cleaning things up. I want to start it to make sure all is good, but I'm letting the MMO soak those lifters.

97grand4.0

Did you take the rockers off and spray down the hollow pushrods? It is a job, taking carefully off the rockers one turn at a time so not to bend the bridges. Also turn it over by hand so the valves are closed when you take them off.. I replaced all my rockers rods pivots and bridges.
If not, you still have the benefit of soaking the plunger, the idea is to get the varnish off the plunger there. I would even turn the engine over by hand a few rotations just to work the plungers a bit, then soak again.
I'll be very interested to see how you make out, I am about to do the same thing, though the autozone manual does say to spray down the 'hollow pushrod' to the lifter. That being said I have been wondering if you could put the spray straw in the rocker oil hole and spray down into the lifter like that.
Either way I would like to know how you make out.

A new gasket is well worth it but also a job to install but once you have it on there you can take the cover off as many times as you like and it wont leak.

97grand4.0

To put the cover on, rotate it right straight up 90 degrees, and slide it ALL the way back, then turn it down and on. lol.

Rickster70

I did not remove the rockers. I sprayed MMO down the holes around the pushrods. I got my sprayer shooting the tightest stream I could and tried to get some down in the rods, but I'm not sure I got much in there.

I picked up an inch/pound torque wrench and tightened it down to 85 per the FRM. 85 did not feel like much, my nature would be to crank it down more, but I am trusting the tool and all the information here.

97grand4.0

Yeah I got a torque wrench at harbor freight for $20. Seems like a good one. 21 foot pounds is the torque 85Nm. If you crank them down all at once without alternating from one to the other you bend the bridge and the rockers dont line up on the valve stem.
I would still rotate the engine a few turns and soak again.
Am interested to hear how it works do let us know.

Rickster70

I purchased the FSM for my '99 Cherokee and it states 10 Nm (85 in. lbs.). Am I reading this incorrectly?



I tightened them exactly as stated in the manual.

97grand4.0

[QUOTE=Rickster70;3431497]I purchased the FSM for my '99 Cherokee and it states 10 Nm (85 in. lbs.). Am I reading this incorrectly?

My mistake. 21ft lbs is the rocker arms.!

The valve covers have the spec you are using. I didn't bother with that because the gasket on mine has small steel spacers that if you just tighten carefully it puts the right amount of pressure on the gasket.

Rickster70

***UPDATE***

I let it soak until this morning. On initial startup, it really sounded about the same, however, it quieted down quicker than before. I stuck my head out the door to check after about 3-5 minutes and it was noticeably quieter. By the time I left for work it had about a 15 minute warm up and was idling very smooth. I visually inspected the seal before leaving and it was dry. I have a 17 mile ride in to work, when I parked, it was sounding really smooth, I once again checked for any leakage and it was dry as a bone.


How do you do this...turn it over by hand? I think I would like to try this after a week or so to make sure I get a good soak in there.

Tbone289

Good deal!

I was hoping it wasn't just me... Mine isn't compeltely gone either--I still hear it a bit after it settles down to normal idle on cold start, but it's gone once I've driven it a few miles. I only let mine soak for about 2 hours, and I regret not doing it overnight like I suggested here.

I think 97grand's suggestion to turn over the crank a couple of times is a good one as well. Soak, turn it over, soak again and let it sit overnight. Just use a breaker bar or long ratchet on the damper nut. It would be easier to do with the plugs out, but will work either way.

97grand4.0

I think 97grand's suggestion to turn over the crank a couple of times is a good one as well. Soak, turn it over, soak again and let it sit overnight. Just use a breaker bar or long ratchet on the damper nut. It would be easier to do with the plugs out, but will work either way.[/QUOTE]

I was able with a cold engine to turn it by just grasping the serp belt with 2 hands, be careful of your power steering pump. But its easy with a 1/2" ratchet on the crank nut, no breaker bar needed. You want the engine cold tho. otherwise you are fighting the compression.

So, not the absolute definitive result I would have hoped for with no change on initial start up...?

Tbone289

I only suggested the breaker bar for easier reach to the crank nut, not for increased leverage.

Mine is quieter than it was on initial start-up than before the procedure but, most importantly, it's quiet after warm-up. Prior to the procedure, I had constant multiple HLAs clattering regardless of temperature.

It may not be the definitive result, I suppose, but at least it quieted down quicker on initial start-up. It will be interesting to see how the results are after a few days.

97grand4.0

**UPDATE**
UPDATE
So I performed the carb cleaner down the hollow pushrod yesterday, took rockers off and stuck the straw right in the pushrod and let the lifters have it. I used Gumout, and the spray was so strong it lifted the pushrod off the lifters! So I knew I was getting in there.. I was still very skeptical and convinced I had piston slap instead. I could almost narrow it to the #2 or 3 cylinders.
When I started it a couple hours later and moved it outside I didn't notice any difference but wasn't really even paying attention because I was in a hurry.

HOWEVER: Later that night I decided to go for a drive, and I can honestly confirm to all that it IS about 80% better! I was stunned. Still light tick on cold start but only for a few moments, vs 10 mins. Most importantly to me, it shows the problem to be with the lifters, and not a broken skirt or loose piston, worn valve guide, cracked exhaust manifold, etc. So the value is in the differential diagnosis.
After multiple starts and drives since including 3 today, I am here to say those results are confirmed. Shout out to Tbone et al and the Autozone repair manual for that one.
I would add that I found a burnt spark plug wire on #1 that had robbed power for a while, and that I changed the oil a couple times in the last month, added the FL-1A filter with anti drainback. (though that was days before and had no effect on the lifter noise, it is still a good upgrade.). I also had changed the timing chain, pushrods, pivots, and rockers, all of which made significant improvements in performance but had little to no effect on the cold lifter knock.

Tbone289

Isn't it great to be (mostly) rid of that clatter?

I plan on doing this about once a year, and I'm probably going to try the straw down the pushrod next time.

Thanks for the update!

97grand4.0

Yes it is great. I might do it again in a few weeks.
You just have to be careful with the bridges, be mindful if one valve is open. If you go too far tight or loosening with the rocker bolts without equaling the other, you bend the bridge then the rocker wont line up square on the valve. Many threads on that one.

Rickster70

Excellent news! Now that I have the new valve cover gasket, I plan to do a thorough soak on those lifters and this time get it down into the lift rods. You used Gumout carb cleaner, think that is more effective than the MMO? Or is the MMO a safer choice?