Julian's '91 200 20vt

[audifreakjim]

Check the regulator. Probably a $12 part.

[88a5tq]

precisely!although i will keep the offer in mind. Nice gesture'. It's one ofthose adjustable regulators so I still have the original here. If I can I'll just replace it while it's on the car still.

I removed the head bolts last night. There was coolant in the ones near cylinders 4 & 5 and one of them wasn't as tight as the others I don't think. Got my ARP studs today also. Wow im glad I live at work. This would drive me crazy otherwise. Thanks Jim,, for the advice.

[88a5tq]

Ive sidelined the stupid 5k until I have more time. It wouldnt even crank yesterday so I suspect a bad battery now instead of alternator. The battery light came on shortly after I left where I was and headed home couple days back but it still had power n whatnot. So question: can the voltage light come on with only a bad battery? Especially on these old hogs. I would think it wouldn't have even gotten me home if the alt was bad. The belt is still on also.

So the 200.. Head is getting lifted off tomorrow. I feel super human doing this myself .. Rain is predicted for the foreseeable freaking future though. Lined up a machine shop and everything online to completely overhaul the seals and gaskets. Shop wants $100 to deck and pressure test it and $75 to do the valve stem seals. That's pretty good right? Local shop friend says he can tear the head down before sending it to the shop. problem is he likes to ask what you can spend instead of saying a price so I might guess hi and get effed lol. I may take the head down my self I think except for valves. Anything else I should have them do? I think that price includes bead blasting but not sure. Although I don't think they will put that dirty ass thing on the mill to deck it. Wouldn't mind it looking super clean when it's done.

[Aktapod]

When I had mine done, it was $200 to give the head a chemical bath, check for cracks, deck it, 3 angle valve job, install new valve stem seals (which I provided), and get it back reassembled with springs - to give you an idea. I do think I got a pretty good deal, though.

What do you mean by tear down? Like, remove manifolds and studs? I'm sure you could do this yourself, if you have the time. Heck, I actually removed my valves too by using an autoparts store rental valve spring compressor and a sketchy adapter I made from a socket to get it to work with a 20v head - Ended up being unnecessary as it would have been covered by the guy doing my head anyways.

[AngryTaco]

$200 for all that and having to deal with 3-groove keepers is a good deal. That's about what it cost me to have the eurovan head gone through, seats and valves cut, surfaced, etc ($185) but I provided the seals

[88a5tq]

Damn Sven, that's one helluva deal! Check this out...

No detonation indicators anywhere

Im confident my ARP's will prevent this from ever happening again

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[loxxrider]

That looks pretty clean. So you must have had some head lift. Could be a combo of the small turbo torque spike, plus some light det. Got any high res pics of the plugs? Look for very tiny black specs with a magnifying glass. I just don't understand why this would happen with this setup and not on my or Nick's completely stock engines, each with over 180k miles at 25+ psi with bigger turbos. I guess it could just be that k24 insta-torque, but I had no problems running my little k24 balls to the wall either.

[AngryTaco]

I would imagine it's the tune honestly, but I also recall Nick having ARPs on even his stock motors so that could be it as well.

Either way, yeah that gasket is B L O W N

[88a5tq]

I'll check the plugs more closely tonight. so while looking over replacement gaskets, I don't see anything resembling a passage where this gasket blew out. I hope there was a revision or something. If it blew compression into the coolant system then there must be a passage I missed on the new gaskets. It looks like the gasket blew into the water manifold pipe and the rest is historic. As far as possibly being the tune, too much timing I guess right? When I get the car back u do you guys see any problem using the same tune while I tweak further? Thanks all.

[GTJeff]

I would get some knock phones and maybe an AFR gauge so at least you can see/hear in real time and let off the gas pedal if necessary and safely tune your timing. Mine is just a lowly 20v but without such tools I'm quite sure that it would be"Angry Taco'd" by now.

[88a5tq]

OH SNAP! Actually Ive been meaning to ask Jared what it was that happened to his car during those 2 weeks he had rod knock. You know, the thing he told us not ask him about.... hah.

Well I took the head over to the drag racer/engine builder dude just because I really didn't want to mess anything up. I took apart a spare 20v head 2 years ago and it sucked working the rigged valve compressor I made with a C-clamp. He's gonna put in my new studs and remove the old (main area I'm worried about jacking shit up), mic the head, and deliver to the machinist. I told him I could take it to the shop myself but he insisted. I guess I need to tell him again tomorrow? There was a knick in the head on cylinder 2 where the gasket went ape shit that we both noticed at his garage today upon drop off. That gasket was waay too freaking 3 dimensional and I think the issue may have occurred when the head came back together after lifting. I decided to have the valve job done afterall. Also the guy is going to check the valve guides for me. I don't have any problem doing this tear down on my 20v but this car is beyond my favorite so I think I'll let the professional take this part on. I feel safer. The reassembly is all on me though.

[88a5tq]

Ok so I have a few big concerns. First off we need to address the scratches in the #2 cylinder head chamber. The deeper scratches look like they were caused by something in the air charge? I say this because this spot is within the chamber and not on the gasket area. That's a relief I suppose. However, I looked just an inch or half inch to the right of those knicks and saw some very light scratches on the cylinder head ON the gasket's metal ring sealing area. The guy tearing the head down asked if I want to have the machinist take 10 thousandths off to prevent any issues and I said most likely. However, I read these heads really should not be decked. Im a bit worried about this decking and how crucial it might be. Has anyone decked this little on an AAN or 3B without problems or have any suggestions. I cant take photos of the head right now since its at the guy's garage. Also I dropped off my Bentley to show him the tolerancing information if he needs it and made him aware that they are sodium valves so lapping is the most I want done if the valve guides are shot. BTW, those dams guides are almost $80 shipped for 20!

Last thing I want to address: whats the best gasket application method? I carefully razor bladed the block and found everything looked great. I cleaned out the head stud holes with a vacuum and brake cleaner and vacuumed again and plan to use brake cleaner to clean the block mating surface right before application. Any steps I should consider besides these? A sealing spray or goo? Thanks everyone. I can almost taste victory!

[88a5tq]

Im a little confused on how the marks got there honestly. The piston tops are flawless. More like the cylinder was set down on something. The scratches on the gasket surface areas really seem to indicate decking is the only option for me.

[loxxrider]

Not sure what to tell you about the scratches without pictures. I wouldn't put the head back on with them there though. You need to determine if decking the head will create a valve clearance problem. Other than that, I can't see how decking 10 thou would be a problem. That's plenty of bite for the tool.

For gasket application, I have had success just cleaning the sealing surfaces. Copper SPRAY never hurts though. For the threads in the block, chase them with a tap a few times each.

[88a5tq]

Thank you. I texted my dealership friend and he said that decking amount will be fine as well. Ill get the pictures tomorrow. I couldnt find metric 11 taps locally so i took a narrow cutting disc to one of the originals to make a small flute on either side. I still dont know the exact thread and pitch though.

[88a5tq]

So I spoke to the shop and they said if all the valve guides need replaced and reamed and aren't centrally located like the old ones, that they will need to cut new valve seats in the head. This shit is scary. I don't want to find out the head is useless after the estimated $425 machining bill because the valves aren't being held to the head hard enough from cutting new seats. They said they can't just lap the valves if they aren't centered like the old ones and the seats need re-cut. True? What do you guys think I should do or ask? TIA

[88a5tq]

So it feels like its been freaking forever since I dropped the head off to the mechanic friend of mine. He told me last Monday it would be going to the machinist by lunch that day. I go and stop in everyday to offer a hand or look at the fitment of the new exhaust manifold etc. today I was removing the original exh. manifold seeing as he wasn't doing it haha but then this calamity caught my eye:

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I almost flipped on the spot.. Do you guys see what I see? The cams haven't been touched by anyone since the headgasket failure so that means that I bought the car with the cams off by 2 teeth. 2 TEETH!! How the hell is this thing running Shit it looks like 2 teeth to me but I don't know. It doesn't even appear to be lined up properly even if the teeth were the only thing off. It looks disproportionately placed according to the teeth on the cams. Am I hallucinating? Anyway what sort of worries should I have now. Compression was stellar when I checked it when I first bought the car and that was on a cold engine with no oil added to the cylinders. Thanks for any advice in advance.

PS all the cam caps were in place and I assume tight still since he said he didn't get anywhere with the car yet.

[AngryTaco]

Maybe my knowledge is corrupted to doing 1.8ts, but arent the dots supposed to line up with dots on the chain? Not eachother?

[88a5tq]

I think this is the goal

[PRY4SNO]

Haha I was going to post that pic of mine, you beat me to it

That's what you're looking for, dots level with the top of the head and seven chain links across the top of the cogs.

[88a5tq]

I just couldn't resist... very good illustration. Maybe that explains why the boost drops off so dramatically at redline? Apparently its not enough of a difference to facilitate valve interference...

[PRY4SNO]

Probably a good chance, though I can't say for sure myself. I'm sure someone who knows will chime in, and hopefully explain if that's advanced or retarded timing.

[yodasfro]

Doesn't look like the cam pulley is at TDC in your pic. So I would say the timing is probably fine. The dot on the back of the cam pulley level with the top edge of the head is TDC. That or plop the valve cover back on and line up the line in the front of the pulley to in the V on the VC. This might also be helpful http://forums.quattroworld.com/s4s6/threads/13406.phtml

[88a5tq]

wow nice thanks yoda. Those are cool. Ya I looked at it again tonight from a lower vantage point and they are off a tooth or two. The mechanic gave me a key to the garage so I cleaned the place earlier and went back 2 hours ago to start pulling the exhaust mani studs (got 10 out and 6 are stuck without heat) and to put the wastegate on the new manifold. It weighs a ton lol so I should probably figure out a method of bracing it. Austin you are right its not at TDC but its only a few degrees off since I set it TDC and rotated the cam sprocket just a little in one direction in order to stick a screwdriver through it and brace it while I removed the cam bolt. I will be sure to get the alignment spot on when it goes back together for sure!

[chaloux]

Put both dots as close as possible to level with the head. From each dot count 7 links up. This means 7 peaks including the dot. Then from one side, count 10 across including the links you are at. That is proper cam timing. The picture above is perfect.