Ever since I took the engine out to build it for the turbo, when it has been back in the car there is a knocking/ticking sound. More of a dull tick really. Anyhow, I just replaced the lifters because I thought that was it. I have a mechanic's stethascope, but that didn't really help me much. It seems to be on the passenger side of the engine, or at least that is where it is loudest.
I can't pinpoint this stupid tick, but I was curious if anyone has suffered a similar problem and what they have tried to do to fix it.

Thanks for the help. I know that this is a vague topic, but every little suggestion helps me narrow it down more and more.

Piston slap? I have the same issue right now. Does it start to go away after the engine warms up or drive it around for a few?

Originally posted by 1slw97
Piston slap? I have the same issue right now. Does it start to go away after the engine warms up or drive it around for a few?

i was about to say that. Let the engine warm to normal operating temps and see if the tick fades away or is gone. If it's still there, and audibly, it hasn't changed, keep searching, youll find it.

Does it fluctuate with rpm's?

Piston slap sounds more like a diesel engine, and most engines built with forged pistons have this noise, but its not much a ticking.

I would be checking the idler pulley for the timing belt. Had a noise for about 3 months before I found it. A constant tick noise, not very loud, but not very quiet either, checked to find the bracket was broken and good thing I caught it when i did.

I've got the same thing, I believe. I didn't drive the car much before I went turbo, so I can't tell you if they correlate or not. But yeah I have forged and that is a different sound altogether. I think the ticking I have is valves, as it doesn't really change much with temp (does somewhat diminish when warm) and changes with RPM. I was told that it could be light valve sticking because of the poor original valve angles... Could be something from the rebuild, also. The only sound issue other than that i've had, and fixed, was a squeaking like a belt, but not a belt. turned out that i'd blocked off all PCV after pulling oil into the turbo one time when it froze outside, and I suppose the gasses were trying to escape past seals or something.

It does change with RPM.
I do also have the Ealge H-Beam long rods in. Do you think those are causing it? Rod's slapping the side of the block somewhere? I doubt that it is the piston.
The other thing I was wondering, it is much too loud to be coming from 'inside' the engine in my opinion. I used a mechanic's stethoscope on it, searching all over the place, and it was not noticeably louder when I touched the block. I figured if something was knocking around in there that I would get a much louder feedback on the stethoscope.

Anyhow, keep the ideas coming.
I feel like it may be something behind the timing cover, but I really do not know what it could be back there. Again, it is REALLY hard to pinpoint the exact location. It is extremely annoying to have a nice fixed up ride, but it sounds like butt when it is running.

If I record it, would there be a way to post the recording on here?

Originally posted by bzoss
If I record it, would there be a way to post the recording on here?

You could post up a recording on youtube.

Did you check for exhaust leaks?

I will try to post the video clip today.

I thought maybe it was an exhaust leak. I is really tough to tell if there is one. I had a real problem with my exhaust manifold warping until I went with an all cast one. I am using that graphitic gasket. Perhaps it has blown out or something.
The other thing... Because that other manifold warped (Cheap e-Bay junk..) it damaged the threads in the head on the two bolt holes nearest the timing belt. I tapped and redrilled them, but I am scared to take the manifold on and off too much because of that. I thought that was what it was a while ago, but you could very well be right.

Um, i deffinately do not think it is a rod slapping the block.

I really didn't think so either. It is not "violent" so to speak. I also feel like it is external. I am starting to lean towards bullet's idea of the exhaust leak.
Because the exhaust manifold bolts were stripped the way they were, I may not be able to get the exhaust to seat properly. I am going to pull it all apart one day next week to see if the gasket shows any obvious signs of leaking.

YouTube.com

Okay, above is the link to the video. The sound is pretty distorted in the video... used my cell phone... Anyhow, the noise is loudest in the area near where my exhaust manifold meets the thermostat housing.
To add to the "it may be an exhaust leak", I could feel some "hot air" blowing around in that area too. The car had not heated up yet, so the fans were not on.

Really starting to lean on the exhaust leak for this one..

Keep the advice coming! Thanks!

an easy way to check for an exhaust leak is to do a seafoam cleaning.

buy a $6 can of seafoam at the parts store and a few feet of vacuum hose that'll fit the nipple for the brake booster vac hose on the manifold.

run the car up to operating temp and shut it off, make sure you're not in a closed garage and get the car out into the open air where the fumes/smoke won't kill you.

disconnect the brake booster vac line at the back of the manifold, put on the hose you got and dunk the loose end into the open can of seafoam.

have someone start the car and lightly feather the throttle just enough to keep the engine from stalling. watch for white smoke coming out of the exhaust piping.

That is an interesting approach. I must admit, I have never heard of doing that before. I may give that a shot before I tear everything apart. Should save me a few hours at least.

Thanks

I will post the results as I get them.

just don't breathe too deeply :P

The "old man" way of checking for exhaust leaks is to take a rag in your hand a block off the tail pipe (No don't stuff it in there, lol. You are just blocking the exhaust from coming out of the tailpipe and hopefully - in this case - from somehwere else). Then just listen for for hisses.

Um, obviously don't hold your rag over the exhaust pipe for too long, lol.

MB

That video sounds is horrible! Sounds like a rod knock from hell - not a small ticking. Might be the audio pickup, but...

It's the audio pickup... I put the mechanic stethoscope right on the block and heard near silence... but the sound is loud and annoying on the outside. I think that it's an exhaust leak... I just need to prove it, or rule it out.

remove the timing inspection cover. At idle, see if your timing belt is flapping dangerously around. If its not, then nevermind. If it IS, shut it off immediately, don't drive it. Inspect for a bad timing (hydraulic tensioner), and/or bad timing/idling tensioner bearings...

I have the cover cut off around the cam gears. The belt 'appears' tight. I put a brand new tensioner in, even though not the mechanical version, on rebuild just to avoid this problem.

Thanks for the idea though. Hopefully I will be doing the bulletdsm version of an exhaust leak test tomorrow. That will be the first day I will have a chance to get to it.

Turns out it IS an exhaust leak. Or at least, there is an exhaust leak. It seems pretty bad. It is basically where the video was shot.
I think it is my cheap cast manifold. I bet that it warped like the other manifold, causing my leak.

Does anyone know of a reputable manifold that will not warp, T3 flange?
Preferably cast.

This one was a cast model off e-bay for $120.00. It seemed to work fine, until this... but try getting them to honor it's warranty... good luck..

cut between the bolts to allow for heat expansion, get it resurfaced, and you'll be fine. Sorta like this:

Excellent! Thanks for the tip. I am going to try and knock this out within the next couple of days. I really hope this does it. I just need to find a machine shop that will re-surface it for me without breaking the bank...

Took the manifold to a respected speed shop in my area today to try and get this thing cut and resurfaced. Turns out, it is warped, but not that bad. The other thing is that the shop doesn't want to cut it. Apparently, according to them if the cut this manifold because it is a cast manifold there is a good chance that will cause it to crack.? I am a little confused, but I don't know if I want to cut it now. I am scared it may mess something up.
I noticed that your cut manifold was tubular. Does that make a difference? I may just get it resurfaced, because it wasn't really warped bad at all. It sat on the counter pretty evenly, but with their special flat checker tools they said it couldn't hurt to have it done... they just want my money...

Anyhow, so also after looking at the gasket, I don't think this thing was really caused by an exhaust leak.
I did however notice that my waste gate was stuck open do to my error when clocking the turbo. The noise is loud, but do you think it is a possibility that the wastegate was flapping around and ticking on the housing?


Thanks for the input.

I had the exact same issue. Get it resurfaced and get a nice MLS manifold gasket. I got the one that Mitsu offers and I have not had this problem since. Also make sure to really tighten down the bolts on the far ends. That is where it warps and where it will leak from. You do not need to cut the manifold. Some guys like to run studs in all the holes, and that also seems to help. Personally, I run two studs in the stock locations and then use hex bolts with lock washers on the rest. Works great for me.

Good to hear someone has solved this problem. I do plan on running studs with lock washers this time. I think I can get away with more torque on the studs without having to worry about stripping any more holes out.

I am going with the factory gasket though. I have always had good experiences with factory gaskets. That is one thing I feel that they do well.

i imagine that your manifold is steel or something other than cast? if so, no wonder it warped. I had a SS turbo mani, the flange warped, like yours, and had it resurfaced. After resurfacing, the sound went away, but it returned months later. Even when sufficient torque is applied, my mani returned to the same warp as it was before. After that, I decided to purchase a CAST manifold. Problem hasn't returned.

My first wasn't cast. It warped REALLY bad. This is a cast manifold, but still is a little off. I think a lot of my problem is with insufficient tightening of the bolts. The lower left threads are stripped fairly badly. I have an extensive thread repair job ahead of me. I was considering epoxying the new stud in in that location.
I am going to replace it all with studs and use lock washers to get as much clamping force as I can without overdoing it.
I wish they had a locktight that would work under that kind of heat...

Just an update.

I feel like this may be the right direction: Valve knock
i.e. The pistons touching the valves ever so gently...

Anyhow, here is the scenerio:
I have adjustable cam gears, so I pulled and advanced timing on both the intake and exhaust side individually and incrementally up to 10 degrees. I noticed a definite change in the noise, but it didn't go away.

I have built this engine twice. I let a shop do it the first time, and did it myself the second because the shop did a horrible job...
Because I have the 1mm oversized valves and eagle H-beam long rods the pistons needed to be fly cut to clear the valves. I specifically had this addressed by a new machine shop when I dropped off everything for balancing. I am starting to think they may not have cut enough (1) or didn't do it at all (2)...

The last thing is, I don't want to take this engine out again any time soon. How long, if this is the problem, will the car make it? What will break first? Signs I should look for if it is beginning to fail.
Keep in mind there are 15k miles on this setup right now.

Thanks,
Brandon

bump... didn't get anythoughts on the update. Curious what you guys have to say.