Not just yet, rebuilding a 964 3.3 turbo
 

It looks like I will need to rebuild my 964 3.3 turbo engine.

http://forums.pelicanparts.com/uploa...1186495543.jpg

I have a phat-phat-phat sound, that at first sounded like an exhaust leak from one cylinder, got much louder, this time from two cylinders and with a dramatic decrease in power. I then shut down the engine and haven't run the car since then. Got it back from Germany yesterday and will perform a leakdown test the next few days to get some more information.

Decided that I will document my rebuild on this forum to get advice, potentially help future 964 turbo rebuilders and to keep the momentum going.

I have a $350 usd/month budget on this project so I will probably hang here for a while....
My car is only run on the track, what I am looking for with my rebuild is reliability balanced with the tight budget I am on (don't want to wait forever to get out on the track).

I will update this post with som more information about my engine.
Edit:
- B&B headers
- KKK 7200 K27 HF turbo 0.9 bar boost
- K&N air filter
- RS engine and gearbox mounts

I have read Waynes book twice before and will now read it again.
Spend the last few days browsing this forum collecting links and useful information.

My first questions is about cylinders and head studs.
What type of cylinder and head studs do I have on my car (I suspect it could be broken head studs)?

After doing some research I believe my cylinders are Mahle and all Dilavar head studs.

http://forums.pelicanparts.com/uploa...1186729192.jpg
Removed intercooler, airbox and exposed the crank vent hose.

http://forums.pelicanparts.com/uploa...1186729320.jpg
Looking into the intercooler at the end connected to the throttle house.
Never seen oil here before.
There where also oil inside the airbox just above the air measuring flap (CIS), never seen that before either.

http://forums.pelicanparts.com/uploa...1186729517.jpg
Looking down into the kompressor part of the turbo, there is some oil here but I had that before, perhaps a little bit more than before (the turbo is newly renovated). The inside of the intercooler (at this end) was completly dry.

http://forums.pelicanparts.com/uploa...1186729644.jpg
So far only removed the upper right valve cover, checked 5 out of 6 head stud bolts and they all seems fine.

Pressurized cylinder 4-5-6 at TDC just to test the concept of doing a leakdown test (never done it before). I opened the throttle but couldn't hear anything, nothing from the exhaust either, but there is air coming through the crank ventilation hose. I gues I should be able to conclude my valves are okey on cylinder 4-5-6?

Next time I will use a real leakdown tester and put oil in the cylinders for better ring sealing.

Oil in the intercooler could be a couple of things: turbo seals, ball missing in the check valve at the pressure sending unit (IIRC).

If you were getting a lot of blow by, then you might see oil in the air box. This is what I had on my 3.3 Turbo (from the 96 piece piston ring option caused by detonation).

But before you take it all apart, check your turbo, hoses, clamps, exhaust for holes, etc. With out the turbo working right and the exahust pushing the turbo you'll be down on power.

Thanks Rocket!

Looks like a dodge a bullit
I am a bit <caugh> embaressed (and "happy"), when I was going to pressurize cyl 1-2-3 I found that the #1 sparkplug was out!!
Couldn't believe my "luck"
The sparkplugs in cyl #2 and #3 came off with very little force.

I remember being worried about over tightening the plugs when I changed them .
The threads on the #1 sparkplug looks okey, but I haven't tried installing a new one.

Does the missing plug explain the oil in the throttle house?

I cut the oil filter in half, found nothing.
Checked all head bolts, seems fine.
The plan is still to do a "real" leakdown test (hope to borrow a tester) and check the numbers.

http://forums.pelicanparts.com/uploa...1186948617.jpg
Is this rocker arm axle, or has it started walking?
Looking in Waynes book, to my understanding the axle should be flush with the "thin" side, right in this case, could anyone confirm?

It's walked a little bit. It should be flush. I'd loosen it, flush it up and retighten it.

Good news on the sprk plug!

Thanks!

http://forums.pelicanparts.com/uploa...1187887382.jpg
I have some "serious" oil leaks around the rocker arms and elsewhere, decided to deal with them while the valve covers where removed.

http://forums.pelicanparts.com/uploa...1187887427.jpg
Decided to remove all the rocker arms and install RSR o-rings.
I will post some pictures on the shafts, would like an oppinion on the wear.

http://forums.pelicanparts.com/uploa...1187887522.jpg
Borrowed a leakdown tester, dialed it in at 50 psi and tried on a cold engine.

http://forums.pelicanparts.com/uploa...1187887451.jpg
All the readings came out between 46 and 47 psi, if I got it right that should indicate a 6-8% leakage.

http://forums.pelicanparts.com/uploa...1187887474.jpg
Seems very likely that the plugs where the problem...

http://forums.pelicanparts.com/uploa...1187887576.jpg
The wheel in my power steering pump was damaged (right one), has destroyed the seal towards the cam shaft, probably a good culprint for the leaks I have.

staffanbe,
If you have oil "above" the metering plate, the only place it can come from is the oil breather hose from the oil accumulator or oil tank. Maybe the oil accumulator has failed or filled with oil? Keep in mind that as our engines age, the amount of blowby through the piston rings increases which in turn increases the amount of gases being forced back through the oil tank. Of course, in the pursuit of more HP, we increase the boost pressures which exacerbates an already bad condition. You may be ok since your leakdown results are pretty good. But then you should try to perform leakdown on a warm engine.
If you track your car a lot, you should consider baffling your oil tank as well. These cars generate some serious cornering G's and you would be amazed on how little oil it takes to move up into the intake tract and start coating everything.
Also, when any engine has oil in the intake tract, this contamination is effectively lowering the octane rating of the combustible mixture. This will increase the likelihood of detonation.

Thanks Dave!
I don't have any ventilation from the turbo oil accumulator (running B&B headers with an aftermarket turbo oil accumulator).
There is oil inside the oil tank breather hose (at the end where it connects to the airbox), so this is something I will follow up on.
Will do another leakdown when I get the engine running.

http://forums.pelicanparts.com/uploa...1188083930.jpg
Removed all the rocker arms on the right side, had no problems with cyl #5 and #6, could easilly push the shafts out. The #4 was tougher, had to use heat and pull the shafts out.

http://forums.pelicanparts.com/uploa...1188084339.jpg

http://forums.pelicanparts.com/uploa...1188084369.jpg
One of the shafts looks like this, seems to have been rotating?
Should I replace shafts that looks worn ?
Read that you should have them polished, should I be worried about the clearance between the shaft and the rocker arm bushing?

staffanbe,
Things are looking good! That closeup photo of the suspect rocker arm does not appear that worn. How does the bushing look for the associated rocker arm? If there is galling on that bushing but the other rocker arm bushing look normal, I would take a look at the oil spray bar and make sure it is not clogged for that cylinder.
I had one of the spray bar holes plug up on #6 cylinder and it ruined the rocker arms, shafts and lobes for that cylinder.

Thanks Dave!
All the bushings seems okey I think.

http://forums.pelicanparts.com/uploa...1188502346.jpg
I put RSR o-rings on all the rocker shafts (right side).
Decided to wait with the left side, it isn't leaking today so it will have to be a winter project.

http://forums.pelicanparts.com/uploa...1188502871.jpg
There was very little space to get a 8mm allen key in the bushing at the #4 intake, had to cut the key real short.

http://forums.pelicanparts.com/uploa...1188502621.jpg
Installed all shafts dry, with very little problems.
Will check the "oil spray bar", when I find it...


http://forums.pelicanparts.com/uploa...1188503656.jpg
A friend reminded me about the fact that the shop overfilled my car with engine oil, could be the reason for finding oil in the airbox. But I will do a new leakdown with a hot engine when I got all pieces together.

http://forums.pelicanparts.com/uploa...1188504977.jpg
Adjusted all the valves.

http://forums.pelicanparts.com/uploa...1189030424.jpg
Put all the pieces together and started the engine.
I am back on square one, still have a "hard" sound from the engine.
The terrible "phat-phat-phat" sound is gone (from the loose spark plug), but something isn't right.

The sound is there at idle, when I raise the rpm (no gear) it's gone.
While driving it's only there when under load.
The sound is "hard", but in my mind not metallic.

I will start by checking for exhaust leaks.

Well, it doesn't sound like a rod bearing. Generally, they will knock when the throttle is released after being under load. They will knock when the engine is idling, however. You may have a crack in your exhaust system somewhere. I've heard of cases where the headers had a crack in the heater boxes.

HI staffanbe
Has the info turnd up?? as it was sent to you last week.

regards mike

Is the sound there when you push in the clutch pedal? I have a sound on my 3.0 that is related to the throwout bearing. It's only present at really low idle speed and goes away with rpm and depress of the clutch.

Great work finding the spark plug.

Those look like B&B headers...I'd check them!!! Especially where the heater boxes attach to the pipes. My B&Bs cracked only after a short while! I thought I had a broken head-stud on my 930 when I developed that "PHAT PHAT PHAT" SOUND. I was pulling a low mileage engine, anyway, to perform a rebuild to fix an endless array of oil leaks, and just got carried away with "while you're in there". However, I didn't think to investigate the headers since they were almost brand new. When my rebuild was complete, I also ran an open "zork" straight pipe on the turbo. The exhaust sound was soooo loud, I never realized that I still had a header leak. It took me installing my current Borla muffler (quieter) to realize that I had a problem.

When I pulled my B&B headers, I shined a light into them and the cracks where VERY apparent! Unfortunately I was just outside of B&B's warranty and ended up running a new set of OBX headers (no heat). I'm amazed at how smooth my engine sounds and runs!

Also, are you sure your rocker shafts are still properly installed in the cam housing? They have a tendency to "walk" if they aren't properly aligned and torqued. Mine did this....was the only gotcha I had with my engine rebuild. I made the mistake of installing them with assembly lube and they kept moving about after the engine had run. I finally had to pull them, insure that their place in the cam housing was totally clean and free of oil, install them dry and then oil them once torqued.

Thank's Dave, been worried about the headers since I installed them, heard all kinds of stories. Even though I only spend 10-12 hours on the track after installing them, I rather take a bad weld or cracks than most of the other things that comes to mind.

Thanks so much Mike, could have arrived the last couple of days without me knowing, let me check.

Thanks Jamie, it doesn't seems to be clutch related.
A friend of mine had a bad throwout bearing just a few weeks ago on his GT3, it was more of a rotating grinding sound, and as you described it, you could make it come and go by playing with the clutch pedal.

I hope to have time to jack the car up tomorrow and use a hose to pin-point the sound.

Edit:
About the spark plug, it wasn't just loose, it was (caugh) out....oh well (blush)

Thanks, yeah those are B&B, not completly happy with them.
Can't run with a silencer after the wastegate because it creates to much back pressure, the exhausts won't evacuate through the wastegate properly on 2nd and 3rd gear, so the turbo pressure goes too high. So I am running with a dump pipe pointing into the ground, it's crazy loud, have to use ear plugs and I love sound.

Thanks, yeah I should check this.
What was the "tell" for you, oil leak or sound?

Actually, a little bit of both. I had installed the RSR seals on my rocker shafts and that probably helped a tad with slowing the oil leak...I just thought the sound was a little loud.

As for checking them, make sure whichever cylinder you happen to be working on, that you've turned the engine as such that the valves are closed for that cylinder...so that the rocker is loose (clearance between the rocker and valve stem). Sometimes the force of the valve spring will give the impression that the rocker is still tight.

Got it, thanks!

http://forums.pelicanparts.com/uploa...1189169294.jpg
I located the sound to the servo pump, removed the toothed wheel and found it to be damaged. It must have tilted while I was tightening it. It has been grinding the servo house cover.

http://forums.pelicanparts.com/uploa...1189169541.jpg
The camshaft looked and felt okey, put everthing back (making sure the toothed wheel had contact with the camshaft during tightening) and started the engine. The "hard" sound is gone, but I still have a "lawn mover" sound which very well could be an exhaust leak. It's really hard to tell lying underneath the car, I will hopefully get a second oppionon later today.

Took the car out for a drive, the turbo pressure builds fast and the car has lots of power, feels as strong as ever. Have a hard time accepting that my allmost brand new B&B could be broken.

Glad you found the source of the sound!

As for the B&Bs, I refused to believe that they could have been cracked. In fact it was pretty damn well hidden. I discovered it because I pulled them thinking that I had a burned exhaust port gasket. When I got them off, I could see that the heater box tube that runs to the front of the car (connects to the cockpit heater hoses) was full of carbon and soot!!!!!!!!!! I shined my shop light into them and could clearly see that on the number three primary pipe, right as it enters the top of the heater box, had a crack!!! I checked the other primaries and could see the beginnings of more cracks/holes.

I think the issue was a manufacturing defect in the way the actual boxes were tack welded to the primaries. It must have weakened the metal.

Keep in mind that this whole internet diagnosis thing can be scary at best...so take all suggestions with a helping of spices. I'd hate to think of you pulling the headers off, only to find that they were fine! Maybe figure out another way of detecting the leak. In my case...I just couldn't pin-point it without removing the headers...YOUR MILEAGE MAY VARY!

Don't worry, I know how hard it is to diagnose these things remote.
Anyway, you and Dave seems to be spot on!

I took the car to a shop today, they spend some time underneath the car with a stethoscope. The verdict is a probable leak (inside the heat exchangers) at #4 and #1 (I think). I was pretty sure about #4 myself.

So, if I get the time tomorrow I will remove my B&B and install the stock headers to check if the "lawn mover" sound disapperes.

http://forums.pelicanparts.com/uploa...1189409297.jpg
Jacked the car up and for the first time in years the right side was "dryish", perhaps the work I did with the rocker arms has paid off, a little bit to early to tell though (I will still check for rocker shafts walking).

http://forums.pelicanparts.com/uploa...1189409002.jpg
Removed the headers and found that the gasket for cylinder 4 was damaged.
Not hard to tell that a lot of exhaust has used an alternate route..

http://forums.pelicanparts.com/uploa...1189408912.jpg
[#4 gasket] My guess is that a nut started to come loose and then the gasket got blown to pieces. The #1 cylinder had some damage to it's gasket as well, but I can't conclude it has been leaking.

Next step is to examine the headers, my plan is to follow the advise I got here and drop a LED-ligh into the headers, might remove the heat exchangers alltogther since I'm not using them.

staffanbe,
The news keeps getting better and better all the time! It's great to hear there's nothing seriously wrong with the engine. The header gasket pictured is the factory OEM gasket. The B&B's were solid cooper. You might try to find a set of copper from any Porsche header manufacturer. The B&B header gaskets I got looked like they were cut by a first timer with a gas torch. Had to mill them flat to insure they would seal properly.

Yep...I'm running metal gaskets in between my headers and exhaust ports. I bought them from our host.

Part number:
930-111-191-12-M17

Thanks, ordered a set of durable gaskets!
http://forums.pelicanparts.com/uploa...1189630160.jpg
Started to examine my B&B headers.

http://forums.pelicanparts.com/uploa...1189630213.jpg
Didn't need to do much cutting before I found a hole in the cyl #1 header.
It's right where the heat exchanger is welded to the header, you guys where spot on!

http://forums.pelicanparts.com/uploa...1189630736.jpg
Looks much better this way and it's a bit lighter too.
1 done 1 to go
Starting to think that I might need to change the title on this thread, but I won't until I'm sure I found all the problems.

ABSOLUTELY UNBELIEVABLE!!!!!! I'm soooo disappointed with B&B!!!!

Those folkers at B&B wanted to charge me $300 plus shipping both ways to fix their bull*****!!!! I threw the gawd damn headers accross my garage, I was so pissed!

here's my thread on it:
http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/345731-b-b-headers-got-god-d-mn-hole.html
Pictures on page 3

Thanks, interesting reading!
My story:

After installation I found that my turbo pressure went to high on 2nd and 3rd gear. It doesn't evacuate enough exhaust to the wastegate. Removed the muffler on the wastegate (to reduce back pressure), still more turbo pressure than I want, but I decidede to live with that and a sound level that makes it impossible to drive on most tracks.

I believe the header must have cracked after about 6-7 hours of track driving, that was when I got this exhaust sound. My turbo started to smoke, could be (but I'm not sure), from pieces of the weld going into the turbo. So I had to have the turbo removed/installed, oil change etc. $500 usd the turbo renovation was another $500 usd.

The sound led me to believe that my engine was going downhill, after a while the sound got worse (probably when the gasket was blown), moments later I lost most of the power (probably because of the spark plug coming loose). Had the car transported from Nürburgring back to Sweden.

It's been "that" kind of season....

Nurburgring??!! You lucky, lucky guy! :D

Oh man, this season has been so much fun but my wallet keept shouting "eject, eject, eject"...;)

http://forums.pelicanparts.com/uploa...1190758664.jpg
Removed the other heat exchanger and found another hole in the cyl 1 header, same spot where the heat exchanger is welded to the header (sorry for the bad picture quality). Just got the headers back from a welder, he found another hole in them, so a total of 3 holes after less thena 10 hours of driving.


http://forums.pelicanparts.com/uploa...1190758783.jpg
Installed a fiber glass hood while I was waiting for the headers to get welded.


http://forums.pelicanparts.com/uploa...1190758942.jpg
This time the headers will be installed with good quality gaskets.

Well, I think 3 holes in the headers, 1 blown header gasket, one loose spark plug and a powersteering pump wheel grinding on a aluminium cover probably will cover most of the bad sounds I heard...

Hope to be able to start the engine in a couple of days, keep your fingers crossedhttp://forums.pelicanparts.com/suppo...s/beerchug.gif

I'm glad you're getting it back together. I'm also sorry for your troubles with the B&Bs! I really think something has changed with regard to the techniques used by B&B to assemble (weld) these pipes. I know of a few people that have had the same set of B&B headers for damn near ten years with no issues. Some might blame incorrect AFR tuning for causing a lean and thus excessive heat situation; my AFRs, however, were checked regularly and were good. Plus most of the failures I've heard about lately have been in the heater-box to primary pipe interface. Nope, I think something is not right at Billy Boat (B&B)! These things cost far too much money not to stand up to the challenge!

Maybe it will take some poor fool to obtain a hefty dose of carbon monoxide poisoning one winter, from running the heat, before something is done!