Jump to content

Diesel Sound And Leaking Head Gasket


Recommended Posts

I've spent a lot of time researching what I can best describe as my 4.0 sounds like a diesel at idle. Hot or cold sounds the same. Bring the rpm s up just a bit and the sound goes away. I cleaned then engine with seafoam and am currently running some of cruzers favorite mystery oil. I recently fixed my ccv problems by thoroughly cleaning the valve cover. Didn't see much sludge. Its not the harmonic balancer, i replaced that not long ago. After the seafoam treatment my oil is staying really clean. Flushed the coolant a couple months ago. It continues to look good. I've watched numerous videos where the engine sounds similar to mine but portended to be numerous different problems. Piston slap, broken piston skirt, timing chain, and sticky lifter all suggested. in this video it sounds exactly like mine and the way he describes it seems to match mine to the t.  https://www.youtube.com/watch?v=29I5fNAv-8M. It's easy to believe my problem is a lifter. engine has 135k miles.

 

On top of all that I have what it would describe as  a substantial oil leak from the head gasket. It's leaking from the distributor all the way to the back. I've never does something as involved as replacing the head and lifters but think it would be a fun a adventure. I'd sure like to get some opinions and advice??  

 

Btw I covered some of this with cruzer on my fast idle idle thread. I've done the flex plate tip and all of cruzers tips that he insisted I do. And I just replaced the knock sensor.

Link to comment
Share on other sites

Yes, Only at idle. I have a steth and the sound is strongest on the passenger side front. It also sounds loud around the oil pan, especially the front.

 

I'm currently running a napa gold filter with some cheap 5-30 and a quart of Mystery oil. My plan was to run it like that for about a thousand miles. then run some more seafoam for 20 miles then swap to a high quality synthetic. I don't think the PO changed the oil in 4 years. It sat parked for quite a long time as he only used for an occasional 1/2 mile trip to the local boat launch.

 

I put in a brand new high quality valve cover gasket a couple month ago. no leaks there.

 

5 days ago I thoroughly washed all the crud off the side of the engine so I could pin point the leak.  Below is a photo of an engine where I've marked in red where fresh oil is seeping down the side of my engine.

 

I also believe I have an exhaust leak. You can hear that classic "puff puff" sound. 
 

 

Link to comment
Share on other sites

My audi mechanic listened and suggested the timing chain. You told me no way on the fast idle thread. I suppose the only way to find out for sure is to open it up and look?

 

I'd sure like to stop the oil leak. I'm thinking maybe I replace the timing chain first then decide what to do with the head gasket.

 

BTW - I found the exhaust leak. There is a metal fabric tube between the exhaust and EGR that's shot. Is that a hokey patch?

Link to comment
Share on other sites

My audi mechanic listened and suggested the timing chain. You told me no way on the fast idle thread. I suppose the only way to find out for sure is to open it up and look?

 

I'd sure like to stop the oil leak. I'm thinking maybe I replace the timing chain first then decide what to do with the head gasket.

 

BTW - I found the exhaust leak. There is a metal fabric tube between the exhaust and EGR that's shot. Is that a hokey patch?

Yep. Extremely rare, especially with your low mileage...

 

Hokey patch on the EGR tube. 

Link to comment
Share on other sites

The early 4.0s (and some HOs) have some headgasket seep. Mine does it too. It's not anything major unless it's just spewing out. I believe they issued a revised headgasket in 92 or 93 that fixed the issue.

Link to comment
Share on other sites

Today I found a marking on the intake manifold that looks like a Chrysler logo. I'm wondering if its possible a Po put a later model intake on, then had to lengthen the egr tube to make it fit. I'm ignorant as to if there is a difference. What do you think?
 

Link to comment
Share on other sites

As to head gasket seep. Its leaking enough to cause quite a mess below and behind. But I'm not getting an oil spot where its parked. I'm wondering if that'll slow down when I switch to 0w40 synthetic or if I could put in an additive to slow it down. My ultimate goal is to rebuilt the engine. But want to wait on that until I've rebuilt leaf springs, front end and new paint. I have to pace myself. In the end if this diesel sound persist after I replace the timing chain and put in good oil my obsessive nature might force me to reorganizing priorities.

Link to comment
Share on other sites

Today I found a marking on the intake manifold that looks like a Chrysler logo. I'm wondering if its possible a Po put a later model intake on, then had to lengthen the egr tube to make it fit. I'm ignorant as to if there is a difference. What do you think?

 

How many bolts attach the throttle body to the intake manifold? 

Link to comment
Share on other sites

My wife's 97 also has a diesel sound at idle. I runs too well, get too good of mileage (23-24), runs too cool, runs too strong.....for me to even think about tearing into it. Even with 240K miles.

 

As to the Chrysler logo......89 is when Chrysler began using their own parts ( believe this to be true), I had an 89 with mixed parts.....what year is yours?

 

As to the leak....have your head decked when  you rebuild, may be warped and not compressed against the block.

Link to comment
Share on other sites

As to head gasket seep. Its leaking enough to cause quite a mess below and behind. But I'm not getting an oil spot where its parked. I'm wondering if that'll slow down when I switch to 0w40 synthetic or if I could put in an additive to slow it down. My ultimate goal is to rebuilt the engine. But want to wait on that until I've rebuilt leaf springs, front end and new paint. I have to pace myself. In the end if this diesel sound persist after I replace the timing chain and put in good oil my obsessive nature might force me to reorganizing priorities.

A true synthetic will make the seep worse, as the base stock molecules are smaller and of a more uniform size than a dino oil's. Personally, I'd jump up to a 10-30 or even a change to Rotella in 15-40 to alleviate some of the seepage. The diesel sound could very well be the timing chain. Rare, but it's still a mechanical comonemt that COULD fail.

Link to comment
Share on other sites

Thanks. My Dad came back from Yuma. He has a yj. Down in AZ he's around a lot of jeepers. Got out his 20" screw driver used it as a stethoscope. Said he thinks valve train, likely lifter. Says he's pretty certain its not the timing chain. I don't know. I'm pretty convinced its a lifter. Think my next move is oil change to rotella 15-40 then start work on the leaf springs. Also bothered by the clunking every time I hit a bump.

 

I will say after doing everything cruzer suggested; fix grounds, eliminate c101, #6, clean connectors, clean Tb, check sensors, adjust Tb my truck is running great. Thanks cruder.

Link to comment
Share on other sites

Retirement. He and my mom have a diesel pusher, own a lot with two motorhome spaces, and a yj, and have a bunch of friends all from Bremerton, WA with similar. They all snowbird. Makes me laugh my mom has her weekly card game with the same gals year round.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...