2001 TJ 2.5 with 180k: Another “engine ticking” post with a twist

Earl LaChance

Earl LaChance

EML 2001 TJ 4cyl
Supporting Member
Joined
Mar 3, 2019
Messages
8
Location
MIAMI, FL
Hi all! I have read countless posts on the 2.5L engine tick. My scenario seems to be a bit different from the numerous threads...details:

Symptoms:
A. When cold (a relative term, as I am in Miami FL), on startup in the morning at idle, zero ticking, sounds perfect. Temp at 100,
B. Within 60 seconds, still at idle, prominent ticking sound starts, seems to be from top of the engine. Temp rising towards normal, 130 at this point maybe...
C. Drive to the gym. 10 minutes away. Idle in parking lot, temp 200, everything humming along as normal. Zero ticking, sounds perfect
D. Return to jeep 60 minutes later, prominent ticking sound immediately on start up, at idle.
E. Drive home 10 minutes, temp back to 200, no ticking, sounds perfect.

... embarrassing as I come out of the gym people ask about the Jeep and then the TICK TICK TICK starts. I hate it!

Completed
1. New lifters, pushrods installed 3 months ago. Rocker arms tight. No difference in ticking sound behavior after the install.
2. Checked exhaust manifold - no leaks
3. Two oil changes in 3 months: with 10w50 thick oil and with 15w30 - ticking behavior the same. Fram oil filters used.
4. New power steering pump
5. New alternator
6. Replaced idler and tensioner pulley
7. Replaced the spark plugs
8. Used the extra long screwdriver-as-stethoscope strategy near the spark plugs, top of valve cover, pulleys and components. You don’t need it to amplify and can not locate as the tick resonates everywhere.

Any thoughts welcome!

This is driving me crazy, mostly as I cannot diagnose what the heck it would be... if flat spots on the cam or some internal part, it should it be present immediately on startup in the morning...Why does it sound perfect the first 15 seconds of idle and perfect after 5+ minutes to normal temp driving? Yet ticking immediately returns after letting it sit and restarting the Jeep, after it cools down ...I would assume heat expansion solving whatever it is at first but that can’t be the case because it sounds perfect when cold first thing in the morning ... I’m baffled...

Thanks for any help or insights.
 
Could u post a vid and capture the tick noise?
It's weird that it comes and goes. Is it causing any misfires?
My 2.5L with 174k has lifter noise but it's consistent.
Surprised the new lifters and pushrods didn't make a difference.
Almost sounds like an intermittent oil flow problem to a lifter, just a guess.
 
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Using the stethoscope trick have you checked at your timing chain? Your rpm when you first start your engine is different than your idle rpm. It is for me anyway. Takes 10-15 seconds for the rpm to settle
 
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So from what I gather (and correct me if I am wrong), the ticking noise only happens when the vehicle is warming up, but once it's fully warmed up and driven for a while, it goes away?

Sounds like a top end / head issue to me.
 
I'm afraid you're not likely to get a resolution on a forum. I have the same issue, as do thousands of others. Will it result in engine failure? ... maybe ... nobody knows. Here's some of the theories and remember that these are very generic at best. Who knows what year the factory made improvements to various parts of the engine.

1. Pistons - rocking in the bores until fully expanded. Possibly leading to piston skirt failure.

2. Poor oil flow in the upper engine.

3. Camshaft fore and aft movement due to lack of effective thrust safeguards. Some older 2.5's used the hollow bolt/spring cam bolt.

4. Failure of the tensioner and/or timing chain stretch.

5. Lifter failure, bent pushrod, weak valve springs, etc.

6. Water pump bearing failure :rolleyes: (hey, it's been suggested).

Personally, I suspect the pistons based on using a stethoscope and that fact that my engine runs it's very best hot - after an hour or two of driving. I've installed a Cloyes timing chain kit (considered one of the best), new valve springs, lifters, valve seals, main and rod bearings, and list of sh*t longer than this thread.

The one thing I would like to have done is to strip the engine down to the point where all the oil galleries could be cleaned but then you might as well rebuild it. Because after I changed the hydraulic lifters, the engine was way quieter - for a few days. But don't confuse this with the startup rattle that this thread is about.
 
Hook_62 said:
I believe you are wrong. The 2.5 is an overhead valve, cam is in same position as the the 4.0 with lifters and push rods.
Click to expand...

Well, I have a 4.0 so I can't say for certain that the 2.5 is OHC since I don't have 1 to look at. However, I do have a FSM. If I am wrong, then so is the FSM. It clearly shows the 2.5 as a OHC design with no lifters or pushrods.

We are talking about a OEM TJ 2.5L motor, correct? I assume so since this is a TJ forum.

Not sure what the issue is here but we got some mad misinformation flowing in this thread and I'm pretty sure I am not the source.

Now having said all that, and assuming the lifter/pushrod replacement was BS or misinformation from another source, and you really do have a ticking sound coming from the OHC valve train, what weight oil are you running?
 
g.hayduke said:
Well, I have a 4.0 so I can't say for certain that the 2.5 is OHC since I don't have 1 to look at. However, I do have a FSM. If I am wrong, then so is the FSM. It clearly shows the 2.5 as a OHC design with no lifters or pushrods.

We are talking about a OEM TJ 2.5L motor, correct? I assume so since this is a TJ forum.

Not sure what the issue is here but we got some mad misinformation flowing in this thread and I'm pretty sure I am not the source.

Now having said all that, and assuming the lifter/pushrod replacement was BS or misinformation from another source, and you really do have a ticking sound coming from the OHC valve train, what weight oil are you running?
Click to expand...
Yeah, mine is 4.0 also and I have no personal experience with the 2.5L. I should have put a ? after my statement as I was just going off the replacement parts diagram. Of course you can't believe everything you see on the internet:

Capture.PNG
 
OK My Bad. I am the source of some BS in this thread after all and I freely admit it now that I have my head out of my ass.

The early 2.5 4 cylinder engines were in fact an OHV design and used through '02. My FSM is for an '05. From '02 onward, the 4 banger was an OHC 2.4L motor.

I did not realize until now there were 2 different 4 cylinder motors in TJs. I knew there was a reason I don't normally chime in on 4 banger threads. I should have kept it that way. Sorry for any confusion I might have caused.
 
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KCsTJ said:
Almost sounds like an intermittent oil flow problem to a lifter, just a guess.
Click to expand...
This is the first thing I would be looking at, check your oil pressure on startup and after warm up. Could be something like a piece of gunk caught up in an oil passage. Run some engine cleaner at the next oil change, like Rislone. There are plenty of engine cleaners out there Rislone is a long term product meant to be used for the entire life cycle of your engine oil 5k - 7k miles. if looking for something quick, I have used Kerosene 1 part to 4 in the past, only left it in for several hundred miles. This actually de-gunked an old 78 Ford 351M, gained more power after and ran like a champ for years.
 
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Thanks everyone... Appreciate the feedback. Will try the Rislone and see if it is oil passages fouled up. If it is piston issues I am not going to mess around around with rebuilding this engine - from what I read I could get a direct replacement 2.5l engine for around $2500 with low miles...
 
I would also go with a thinner oil. No more than 10W30. If the 10W50 didn't help then stick with what flows easily through the engine. It sounds like it could be a timing issue. Can you confirm the cam to crank timing? I had a CJ-7 that had the distributor turned something like 50-60* advanced. Ran ok but had no top end power. Figured it was carb issue. When hot if I let off gas it would backfire thru the carb a few times. Small pops. No big flames. Had the problem over a year with me playing with it on and off. It ran pretty good. Just no top end. When I finally found the problem it was an easy fix. But how in the world could it run like that? It was smooth. Needles to say the carb had to be completely re-tuned after. Anyway, seems like that kind of thing. Try to verify all timing, spark plug wires, etc.
 
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*Update: 10w30 and rislone are in the block... No changes so far. Here is the video
zero tick sound at startup then 30 seconds in ...tick starts. Then ticking goes away at full temp (200).

If it were the wrist pin or piston slap or something cam or exhaust manifold or metal related (that may go away once the metal heats up and expands), if it were one of those then the sound should start immediately at startup, which the sound is not present at startup for first 30 seconds...

As mentioned I personally changed the lifter and pushrods. Rocker arms are tight, too.
 
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Chris said:
Yeah, this one has me a bit confused :confused:
Click to expand...
2.5L has OHV... You can change the lifters without removing the head. I did it with my own greasy hands! See the diagram someone posted previously. Lots of different engines over the years so I get the confusion. 2001:
2.5L I-4 151 cu in - 1997-2002
* 120 hp @ 5,400 RPM * 140 ft/lbs @ 3,500 RPM * OHV * Sequential port fuel injection * 2 valves per cylinder * Compression ratio = 9.10:1 (01-02
 
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