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Eliminating the "tick, tick, tick"

BTW Mike, you never went over 2400 RPM for that long of time?


what's wrong with that??? The '88 hasn't seen over 3000rpm since at least 2007.... 33's and 3.55:1 gears with an automatic and all in town driving commute. Maybe I should go flog her for a few minutes and see if she quiets down:wave1:
 
3500 to 3700 seems to be the sweet spot for mine. Takes less time if it is warmed up first.

I came home from the store with it all warmed up. Kept it at 3700 RPM for 3 minutes. Shut it off. Drove it the next day and no ticky.

And yes, Shorty, you need to flog it more often. The Jeep I mean.
 
Yep, 5-90 said there is something about the >3000 rpm area that gets the lifters to start rotating again, thus unsticking them.

Lifters rotate when ever the engine is turning. If they didn't you would flatten a cam lobe in no time.
 
Lifters rotate when ever the engine is turning. If they didn't you would flatten a cam lobe in no time.

Why would it flatten the cam lobe?

They are suppose to rotate yes, to spread the lifter bottom surface wear evenly, IMHO, but the 4.0 lifters have a nasty habit of getting dirty and sticky, and sticking, and when that happens they make a ticking sound. There is something in the design that makes them rotate, and the force to make them rotate increases at higher rpms (thus unsticking them), from what I recall from 5-90.
 
Its the internals of the lifter that are sticking, which do not rotate, not the lifter itself. The internals get gummed up (or how every you want to phrase is) and stick. Its the internals thatc ontrol the lash, too much lash from a sticking internal and you get space, which is what makes a racket. What makes the lifter rotate is the taper on the cam lobe and the concave face of the lifter (its not actually flat). One of the checks on a new engine is to turn the engine over and make sure that the lifter and/or the push rod rotate. If they do not they do not something must be done about it.. either swapping lifters around for that exact fit, or honing the lifter bore. If the lifter doesn't rotate it will be rubbing on that one spot, which would eat a lifter and/or cam lobe.

Also, there was a TSB about the valves not rotating if the engine is not run above 3200 rpm and building up carbon on the seat, causing misfires. http://www.wjjeeps.com/tsb/tsb_wj_0900303.pdf Which sounds like what 5-90 had mentioned.
 
Great feed back, thanks! Now all I need is lifter part pictures, so I can see what you are talking about, LOL!

I don't recall the smaller details of seeing taper on cam lobes, and the concave area on the lifter that "makes it rotate". Might be why I did not recall the details before when 5-90 explained it. I have seen and held lifters and cams, but missed the fine details, IOWs.

I once made a living selling cleaning equipment to engine rebuilders, years ago, but there are odds and ends like what you described that I am still picking up piece meal over the years.
 
They are suppose to rotate yes, to spread the lifter bottom surface wear evenly...

Well, I thought they just went up/down.

Its the internals of the lifter that are sticking, which do not rotate, not the lifter itself. The internals get gummed up (or how every you want to phrase is) and stick.

Also, there was a TSB about the valves not rotating if the engine is not run above 3200 rpm and building up carbon on the seat, causing misfires. http://www.wjjeeps.com/tsb/tsb_wj_0900303.pdf Which sounds like what 5-90 had mentioned.

It's highly possible that those internals are either stuck or..broken, because they were stuck. Like I said the Jeep runs very well, idles very well, no backfire, no negative driveability issues, plenty of power.

I have run it up and down the hills at or above 35K often. Although the thing only has 300 of MY miles on it. I did run it up a 15 mile long 6% grade, in 3rd, at ~38K and it didn't tick when I stopped and idled, but it seems to come back the next day.

I tried to check the manifold today but work called me away, maybe tomorrow.
 
Lifter pictures? http://www.jeepstrokers.com/forum/viewtopic.php?f=5&t=1262

You won't see the taper on the cam nor the concavity of the lifter with the naked eye. However if you hold a straight edge on a cam lobe you can it at a slight angle. And on the lifter you will see light on either side if the straight edge is centered on the lifter. And by straight edge I mean a mechanist straight edge, not your office ruler.
 
I have run it up and down the hills at or above 35K often. Although the thing only has 300 of MY miles on it. I did run it up a 15 mile long 6% grade, in 3rd, at ~38K and it didn't tick when I stopped and idled, but it seems to come back the next day.
Try using some form of detergent like Rislone, Marvel Mystery, Sea Foam ATF, etc. Then give it a hard drive several times. Get the engine oil nice and hot, which is about 15 minutes after the coolant hits 210*. Running that 15 mile 6% grade will be a good work out. After doing that several times and letting the detergent do its job change the oil. I would say 500 miles with the detergent.
 
Mine did not go away completely until after multiple daily cycles, daily cold to hot, run up the RPMs, cycles, but each trip, or cycle it got better, till it just disapeared completely. I had already driven it as a DD for 3-4 years, 24,000 miles with the ticking, and tried every snake oil under the sun to clean it up. 3500 rpm (which by the way is 3.5K, 35K is 35,000 rpm) for about 30 seconds each morning did the trick!:passgas:

Talyn,

I read that PDF, it is about the newer HOs, and about carbon making the exhaust valves stick, it does not mention sticking lifters, although I wonder if they would sound much different, or if by the time one has happened, perhaps both have happened? I pulled pieces of solid carbon 1/2" to 3/4" thick out of the head on my daughters 89 jeep 4.0, when we pulled the head 2 years ago. And it was not the one with a ticking problem!!! LOL, It had a blown head gasket between #4 and #5 cylinder walls! Red hot glowing Carbon had burned through the thin gasket between the 2 cylinder walls!!! It was the only leak point in the head gasket!

5-90 is our resident Renix engine, and Renix jeep expert, 87-90 engine, so I suspect his feed back was had a much older source? Maybe he will drop in and find out if he recalls where he picked it up, and his version of the story.

But I will say this, both the gumout/carb cleaner to clean up the exhaust valves (2 hour soak, after loading it up at idle in the throttle body), and MMO in the oil, and then run the peyotes out of it, should be standard procedure for a sick 4.0 (or most engines) that have been abused by commuter, local driving on short trips!
 
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Great photos and tear down shots. First time I have ever seen all the guts of one layed out and the complete drawing details. Lot more complex overall than they look like from the outside!!!!
 
Talyn,

I read that PDF, it is about the newer HOs, and about carbon making the exhaust valves stick, it does not mention sticking lifters, although I wonder if they would sound much different, or if by the time one has happened, perhaps both have happened?
I posted that in reference to the above 3k RPM thing. A sticking valve can cause a ticking noise if it is held off the seat then decides to slam shut against combustion pressure. The only thing I can think of that is special above 3k in regard to the lifters is perhaps slight valve float allowing the lifter to try to expand to take up the lash.

5-90 is our resident Renix engine, and Renix jeep expert, 87-90 engine, so I suspect his feed back was had a much older source? Maybe he will drop in and find out if he recalls where he picked it up, and his version of the story.
There are only minor difference in the Renix block vs. a more modern 4.0L, none of them have a bearing on a lifter tick issue. Now, going back to the TSB PDF there is a different in the valve train. The later model 4.0L head has the 3 ring valve locks. The advantage of those is that the lock locks against the retainer, not the valve like earlier 4.0Ls. This allows the valve the ability to rotate.
 
Great feed back, thanks! Now all I need is lifter part pictures, so I can see what you are talking about, LOL!

I don't recall the smaller details of seeing taper on cam lobes, and the concave area on the lifter that "makes it rotate". Might be why I did not recall the details before when 5-90 explained it. I have seen and held lifters and cams, but missed the fine details, IOWs.

I once made a living selling cleaning equipment to engine rebuilders, years ago, but there are odds and ends like what you described that I am still picking up piece meal over the years.

My 92 FSM explains how to disassemble them. With accompanying photos, of course.
 
Try using some form of detergent like Rislone, Marvel Mystery, Sea Foam ATF, etc. Then give it a hard drive several times. Get the engine oil nice and hot, which is about 15 minutes after the coolant hits 210*. Running that 15 mile 6% grade will be a good work out. After doing that several times and letting the detergent do its job change the oil. I would say 500 miles with the detergent.

Good advice here.
 
There are only minor difference in the Renix block vs. a more modern 4.0L, none of them have a bearing on a lifter tick issue. Now, going back to the TSB PDF there is a different in the valve train. The later model 4.0L head has the 3 ring valve locks. The advantage of those is that the lock locks against the retainer, not the valve like earlier 4.0Ls. This allows the valve the ability to rotate.

I have not been into the guts of an HO yet. Only read bits and pieces here about differences. I am under the impression the cam is different (as well as the head), but that is probably not relevant to the topic.

Not sure I can picture the 3 ring valve lock, pictures? LOL:D

I have re-assembled the Renix head, so I recall what it looks like.
 
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