[downest]

So I've put on just over 10k since I rebuilt it, and it's dead again. I was running autocross today with too little gas, I think it leaned out in a corner and detonated. It sounds like a dropped valve when it's running, I haven't pulled it apart yet. I took the valve cover off and everything is there on the top side, so I don't know. Also its leaking oil all over the timing belt side, but it stoppped when the car was off. It idles ok, sounds like a bad valve lash job, but when it's revved up it gets loud and knocky and then dies instantly. I put more gas in it, but nothing changed. Anyway, I don't know what I'm going to do, I have a borrowed car for a couple of days, but I can't afford to do too much to the motor right now. Instead of going home to see my parents tonight for Easter, I'll be in the shop all night, tearing down my A6. Tomorrow I have to decide what to do, and monday is a day off so I'll be scouring the local yards I haven't been to yet. Sorry to vent so much, but this really sucks, I didn't think the gas was that low, and I certainly have never heard of that happening before.
on the better side, I beat a ferrari, and got 3rd place overall, after an EF and EG Si.

 

[baker_jeff]

I beat a ferrari

Sucks that your engine died... but man, with a quote like that personally I'd think it was worth it!! :lol:

Hope it's not too serious and you can get it fixed soon!

 

[SETI20]

odd... would be a first to me for a car dying or leaning out due to lack of gas.

It usually just hiccups and dies. Shouldn't eat the valves.

 

[Ragnaarok]

*taps playing*

man that sucks. you must of been pulling some HARD corners to starve the fuel pump, if that's what you were saying happened. hope you can get it running again without too much work, good luck and start saving for a b-series!!

 

[downest]

I don't want a B really. If the head and/or pistons are screwed, I'm going to start looking for a Z6 or Y8 head, and I met a guy today who has a D16A1 and is willing to sell me the motor (for the pistons). I read about someone (Dren?) doing this recently, and I like the idea of building up a D series, not too much power, not too much extra work. I don't know though, I'm kind of broke and I really need to get my car running. My friend is lending me one of his cars, he has 2 and a bike, and doesn't drive much right now, but it doesn't get great mileage like the CRX and I don't want to borrow it for more than a week.

 

[downest]

Just got home for the night. I pulled the head, and everything is fine. the valves and chambers are clean, there was a little black stuff, but it wipes away with my fingers, looks just like when i put it together in the summer, and none of the valves or tops of the pistons are damaged. One of my friends suggested that the timing belt may have jumped a tooth, the tension in it didn't seem right, it was a little looser than normal. It was also covered in oil, so that came from somewhere. Would timing make that noise? I can understand that it would die when I gave it gas then, since the car was stationary, and nothing was turning the motor. How much does a new tensioner run? I'm planning on pulling the motor out anyway to clean it up and look at my clutch, I got everything out but the speedo cable. The manual says to just pull it out, but it doesn't want to come. I tried taking off the little tab next to it and prying it up with a screwdriver but it's still stuck. As soon as I get that out I can pull the motor and take a look at the bottom end. Would a spun bearing or something allow the motor to run?

 

[SETI20]

There are numerous seals on the head and the bottom end.
The pulley one is notorious for leaking.

Could be it slipped due to leaking too.

 

[coldtotouch]

dude i'm sorry to hear that!

D all the way, keep that a6 goin bro!

oh, and good kill on the ferrari!

 

[Dren]

if you get the pistons from the A1...use the rods too. the A1 rods are the best D serries rods. you can run b serries I believe, but you have to do some machining to your block to get them to fit. i will let you know how things turn out with my pistons. it looks like the previous owner had a valve hit one of them....hopefully he way over revved it and was running a larger cam. i'm going to do a clearance check before i crank everything down tight. i am running an A6 metal head gasket so it should add a tad for clearance issues.

nick

 

[dohcrxl]

Tom, you should've cleaned up the oil, confirmed valve timing, then did a compression test first. That could've given you some direction in where to start looking for the problem. My thinking is that if the belt jumped some teeth then was near redlined, that could be enough for a piston and valve to just tap eachother. You wont be able to see this with the naked eye.

Yes, a slipped T-belt can cause noise in the form of detonation if the timing is too far advanced.

I think a spun bearing would allow the engine to run. Noise of course would be accompanying it.

 

[downest]

Thanks Heu, so what should I do? Put it back together and run it? I'm leaing shortly to go finish up pulling the whole thing out, so I'll be taking apart the bottom end. Is there any way to tell with the motor apart? Also, what does a spun bearing look like (or will i know when i see it?).

 

[SETI20]

Bearings will be shot to hell.
They'll be scarred and discolored.

 

[downest]

Will I be able to see it without taking the rods off?

 

[rex2nr]

probably not. I had the bearings on my ZC overlap each other and could barely tell with the rods on. The only way I could was that the bearings had smooshed out the side of the rod. If it was a rod knocking, it would be a loud continuous clanking noise from the bottom end.

good luck with everything

 

[downest]

Well, I had the motor out of the car today, took apart the bottom end, and it's all fine. I guess it just jumped a few teeth. I also got to look at my clutch finally, I've always had a heavy pedal, so I assumed there was something wrong with it. That's also fine, the pressure plate is a little worn, but nothing too extreme. Getting the tranny back on the motor by myself was a PITA, took me almost an hour. The block and tranny are back in the car now, the head will go back on in the morning, hopefully I can drive it tomorrow night. I'm hoping none of the valves were bent. There are no marks on either the valves or pistons. I'll set the timing and try it out. If it's still bad, maybe it's time for some upgrades. I'm going to replace the timing belt tensioner too, I'm assuming it's bad since the belt was so loose.

probably not. I had the bearings on my ZC overlap each other and could barely tell with the rods on. The only way I could was that the bearings had smooshed out the side of the rod. If it was a rod knocking, it would be a loud continuous clanking noise from the bottom end.

good luck with everything

The noise was definitely the top end, cylinder 1. It wasn't too bad at idle, like I said, a valve ticking sort of thing, but it got loud and killed the motor at higher RPM. Still have my original bearings, I didn't replace them in the summer, and they are still factory fresh looking.

you get the pistons from the A1...use the rods too. the A1 rods are the best D serries rods. you can run b serries I believe, but you have to do some machining to your block to get them to fit. i will let you know how things turn out with my pistons. it looks like the previous owner had a valve hit one of them....hopefully he way over revved it and was running a larger cam. i'm going to do a clearance check before i crank everything down tight. i am running an A6 metal head gasket so it should add a tad for clearance issues.

Will the A1 pistons just go right in, or do they need to be modified?

 

[Dren]

I will let you know tonight or tomorrow. Everything I have heard states that they will go right in. I believe every D series piston is the same size. I think the stroke was just modified along with rod length to get the different displacements.

 

[downest]

Got it all back together and in today. Everything is fine, set the timing and hooked it all back up, but now it won't start. I checked everything, it's getting fuel and spark. The starter is moving really really slowly, I can count the revolutions. When I removed the harness, the small wire on the starter broke at the spade terminal, so I was holding it on there to start, I'm thinking it may be a bad enough connection to keep it from turning over fast enough, and thus not starting the motor.

 

[dohcrxl]

Getting the tranny back on the motor by myself was a PITA, took me almost an hour.

Tip for next time: Lean the engine back so that it is sitting on the driver's side edge of the oil pan and with the crank pulley touching the ground. In this position, the engine will hold itself up and at an angle. You can then lift the 70lb tranny and easily fit it onto the engine.

I'm going to replace the timing belt tensioner too, I'm assuming it's bad since the belt was so loose.

It's not a bad idea to replace the tensioner but don't assume that it was bad. Remember the tensioner's job is only to apply pressure when the tensioner bolt is loose. Once you crank down on that 14mm, however tight the belt is is how it's gonna remain. (unless the 14mm is not tight enough and allows the assembly to become loose with engine and road vibration) The tensioner at this point is no longer putting pressure on the belt. That tension has already been locked down by the 14mm. Also very important - if a tensioner is suspected of not applying the appropriate pressure to the belt, it is because the spring attached to it has weakened over time. Replacing the tensioner alone wont fix the problem. A brand new spring has to accompany it.

Tip for getting the most tension on T-belt: Slip the belt over the cam gear and position it as close to the way it would run once the engine is running, meaning not too much to the inside or outside. Next spin the engine counter-clockwise with your 17mm a whole 4 revolutions of the crankshaft(2 of the camshaft). This will allow the belt to find its center. The reason this is so important is because if the belt hasn't found its center yet and you tighten the 14mm, once the engine starts and the belt spins around a couple more times, it will loosen up just a tad finding its way to center. Finally, slowly turn the crank with your 17mm until you find a spot where there is the greatest amount of resistance. What I mean by this is that when you are turning the crank by hand, you can feel the tension increase and decrease because of the valve springs and the compression in the engine. In a cycle of the tension increasing and decreasing, if you find that spot where the tension is greatest, it is where you will put the most tension on the belt. At this point, stop turning the crank immediately, do not touch the belt, and just crank down on the 14mm. Of course spin the crank 2 more revs and recomfirm timing.

 

[dohcrxl]

The starter is moving really really slowly, I can count the revolutions. When I removed the harness, the small wire on the starter broke at the spade terminal, so I was holding it on there to start, I'm thinking it may be a bad enough connection to keep it from turning over fast enough, and thus not starting the motor.

I wouldn't think so. Try charging the battery or jumpstarting.

 

[downest]

Ok guys thanks for the help, still no start. I think it's a tranny issue, I posted in the technical forum where it's more appropriate: link. Thanks so much for the help so far. It's been a long time since I needed something from the forum beyond addons, I guess that's good since it means my car was running well, but I forgot what it's like when your car isn't working and you can't figure out why. It sucks. At least it's good to know there's an army of home mechanics out there who are willing to help.