Overheating | Bad Idle | Backfiring = the suck
#82
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3rd times a charm I guess.
Went back again for the 3rd time to check the timing belt. Everything appeared to be in order so I was pissed off. Then I got smart and wanted to triple check TDOC. So instead of trying to align the notch in the gear, I used to TDC mark on the pulley for ignition timing. Turns out when everything was algined as I thought it was, the crank was closer to 4°, bolted it back up, cranked it up and it's purring like a lion again (still open DP). So should have it back on the road later today.
Went back again for the 3rd time to check the timing belt. Everything appeared to be in order so I was pissed off. Then I got smart and wanted to triple check TDOC. So instead of trying to align the notch in the gear, I used to TDC mark on the pulley for ignition timing. Turns out when everything was algined as I thought it was, the crank was closer to 4°, bolted it back up, cranked it up and it's purring like a lion again (still open DP). So should have it back on the road later today.
#84
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no...well I hope not. I tried to physically move it and I couldn't. But what I noticed was the slightest movement on the crank would move the postion on the timing marks 2-4°.
so even while I visually looked at crank gear notch and it looked to be in perfect alignment, it was off enough to throw things out of wack. When I decided to get smart and align TDC to teh timing marks instead and completely ignoring the crank gear, it's when it was easier to make sure everythign was exactly where it should be.
so even while I visually looked at crank gear notch and it looked to be in perfect alignment, it was off enough to throw things out of wack. When I decided to get smart and align TDC to teh timing marks instead and completely ignoring the crank gear, it's when it was easier to make sure everythign was exactly where it should be.
#85
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Quick update.
so the thing had run great while cold. once warmed up it ran hot, went back to the lumpy idle, and lost vacuum again and tune was off.
let it cool, started it back up and it was fine again.
I didnt touch it again till today cause I knew the head was warped at this point, but just threw a leak-down gauge on it to make 100% sure before I pulled it off. But #4 although only 15% loss (when cold) lost it straight into the coolant passages.
I had already planned getting my swap head machined (it was already at the machinist) but since there were incompetent, decided a different route.
Currently Brian (NeoGenesis) is going to be porting and polishing a spare head for me. So as long as I have to swap it, might as well get a little performance out of it. I'll also probably be working on a coolant reroute. So once done, I'll have a great start for the next build. This way I can focus on building shortblock, and then all I need is cams and the valvetrain and I'll have a beast.
so the thing had run great while cold. once warmed up it ran hot, went back to the lumpy idle, and lost vacuum again and tune was off.
let it cool, started it back up and it was fine again.
I didnt touch it again till today cause I knew the head was warped at this point, but just threw a leak-down gauge on it to make 100% sure before I pulled it off. But #4 although only 15% loss (when cold) lost it straight into the coolant passages.
I had already planned getting my swap head machined (it was already at the machinist) but since there were incompetent, decided a different route.
Currently Brian (NeoGenesis) is going to be porting and polishing a spare head for me. So as long as I have to swap it, might as well get a little performance out of it. I'll also probably be working on a coolant reroute. So once done, I'll have a great start for the next build. This way I can focus on building shortblock, and then all I need is cams and the valvetrain and I'll have a beast.
Last edited by Braineack; 08-20-2007 at 02:33 PM.
#86
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Finally pulled off my head this weekend as my new one is ready to go....found the problem. It doesn't seem that the head is warped, but two of the passages through the gasket near #4 were fubar....dunno how they got like this, but this was the point of failure. As I had about a 15% leak through the cooling system.
#90
I made the same plate for mine i hope you used decent gauge steel. The first one i made leaked abit cause boost deformed it think it was 16gauge or something the thicker one i have now holds up fine though. Also that HG looks melted WTF would cause that? Do you think you got a faulty gasket to start?
#92
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what I pulled was the air valve...and that opens a valve in certain conditions that allows coolant to pass through the idle valve below the TB....
yep. It goes from the head to the TB, the to air valve, to the thermostat housing.
Richard, IIRC it's 16g SS. It wont bend.
besidess the block off plate, which is kinda obvious, what do you do? rip all the lines off and plug the holes?
Richard, IIRC it's 16g SS. It wont bend.
#94
I havent read over the whole thread but have you tried changing your plug wires? I had the same exact symptoms once and after 2 months of working on the car every day, replacing every wire from the steering wheel forward, replacing injectors, fail, pump, IAT, ignitor, ECU, distributor, etc etc etc. and selling the car broken, I came to realize it was just a bad plug wire. It was an NGK too. :(
#96
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