Crank pully came loose now oil in the water.

[burninator]

This story ended up getting pretty long. Sorry in advance.

 

So, last winter I buy an L28 a buddy of mine pulled from a junk Z for $50. I swap out my L24 for it and I'm driving it at autocross events all summer long. This car isn't street legal and only gets driven at autocross. Last week it was having a lot of trouble starting but it was a bit chilly that morning and my choke cables aren't hooked up, so I didn't figure it was a big deal (I don't know if that part is relevant or not). On my 3rd run of the day the car makes thump and I figure I hit a cone coming up to the next corner the car dies I went to restart it when see the corner workers waiving their arms and notice there is coolant everywhere. On investigation the crank pulley flew off and hit the radiator and busted the bottom tank wide open, everything else looks fine.

 

I have no idea why it died, I was kinda doubting the car overheated enough to die of it in that short amount of time. I had been watching the temp gauge right before the run and it was normal. That to me indicates the crank pulley was at least on enough to be still spinning the water pump when I started the run for what that's worth.

 

A couple days ago I bent and hammered the tear in the radiator back in place and soldered it all up, cleaned and tested it, no leaks. Yesterday I finished getting stuff back together, filled it with fresh water, and ran it until it got hot. Seemed to be running just fine. Today I went to check the water level and there is oil floating in it. Checked the oil and there is water in it.

 

I'm guessing I have a blown head gasket. Right? Must have gotten hotter than I thought in a big hurry. Anybody have any thoughts?

[Challenger]

One thing to note, even if the nut was removed the water pump would still spin as normal. The little key that keeps the pulley at the right spot would keep it rotating.

 

Was the bolt on the pulley damaged? Any idea why it came off? Just wasnt tightened enough?

Edited August 21, 2010 by Challenger

[burninator]

The bolt was not damaged. I'm guessing it just wasn't on tight enough and eventually worked itself loose. I have no knowledge of this engine before I got it other than I guess the car had been sitting in a field for a while.

[rossman]

Anybody have any thoughts?

 

Was the Woodruff key still in the nose of the crank when you reinstalled the pulley? Was the key, crank or pulley damaged?

 

Sounds like a blown head gasket to me.

Edited August 21, 2010 by rossman

[burninator]

The Woodruff key was still there. It was a bit deformed but not bad. The pulley had a little bit broken off around the key, but looks like it would still hold fine.

[aarang]

I would not reuse the key or the pulley/damper. I had one come off a long time ago and I reused it thinking it looked OK. It came off again a month later after it cracked through the woodruff key slot, tearing up the end of the crank and destroying the front cover and radiator to boot.

[burninator]

Yeah, I thought about that. I'm thinking about not reusing the engine at all. I think I have a line on another L28 and the easiest and possibly the cheapest way for me to get the car running again might be to swap the whole engine.

[RedNeckZ]

Check the pulley for a hair line crack. Had one do the same thing to me. The guy that had the car before me had replaced the two belt with a 280ZX three belt pulley and cracked it putting it on. I would also replace the key with a new one. Good Luck with it. Rich.