Car Stalled And Won't Start, Turns Over, Has Spark And Fuel, Ideas?

[Simon-S14]

i doubt it would have... worst case it would have put a dent or mark in the piston... if thats the case file/sand it out and keep going. the valves are weak as piss in comparison to the piston.

[laggn til 3500?..worth it]

hey man same thing happend to my car was getting fuel and spark but fuel pump was f*ked...it was a walbro rip off from ebay...got a genuine 550hp pump put in and started straight up...

worth getting checked out

[DVS JEZ]

Have a read on the last page man. U will see his camshaft is snapped

[Rolls]

i doubt it would have... worst case it would have put a dent or mark in the piston... if thats the case file/sand it out and keep going. the valves are weak as piss in comparison to the piston.

Yeah will soon see once I get the head off, just need to find time to do it!

[Simon-S14]

if you were in sa i would have come around and done it for you by now

[Rolls]

Pulled the head off tonight, all valves are 100% intact and so are all pistons, zero contact made, I am completely f**king stumped. We turned the cam over by hand in the head when it was off and all valves opened/closed and sealed visibly fine. Cylinder 1 was fairly sooty but all other cylinders looked good, all bores look fresh with no marks, however there was MASSIVE play with the pistons, the clearances are so big I can visibly see the piston rings on them all, I'd say there is 20 thou or greater clearance between the cylinder to bores, explains the loud piston slap.

Due to the ridiculous piston clearances and the fact I have no idea why it runs on 4 cylinders I am going to get another motor, as with one of the cam bearing caps stuffed I have to get another head, and being as there is a chance something else is wrong I might as well just replace the whole motor. Lots of bolts were finger tight or very loose as well, I am not confident the builder had any idea what they were doing when they put this together (saba**** in vic)

Anyone got any ideas? Cam turns over fine, all valves visibly seal, all pistons seem to be fine, but it runs on 4 cylinders and it snapped the cam in 3 places? I don't really care if I solve it as I am just going to replace it anyway, this is as I have zero confidence in the build plus no idea on the issue, but for curiosity sake I'd still like to know what went wrong.

Edited April 21, 2011 by Rolls

[DVS JEZ]

Cam most likely snapped due to incorrect install. But some how stayed together for this long.

[The Dan]

Pulled the head off tonight, all valves are 100% intact and so are all pistons, zero contact made, I am completely f**king stumped. We turned the cam over by hand in the head when it was off and all valves opened/closed and sealed visibly fine. Cylinder 1 was fairly sooty but all other cylinders looked good, all bores look fresh with no marks, however there was MASSIVE play with the pistons, the clearances are so big I can visibly see the piston rings on them all, I'd say there is 20 thou or greater clearance between the cylinder to bores, explains the loud piston slap.

Due to the ridiculous piston clearances and the fact I have no idea why it runs on 4 cylinders I am going to get another motor, as with one of the cam bearing caps stuffed I have to get another head, and being as there is a chance something else is wrong I might as well just replace the whole motor. Lots of bolts were finger tight or very loose as well, I am not confident the builder had any idea what they were doing when they put this together (saba**** in vic)

Anyone got any ideas? Cam turns over fine, all valves visibly seal, all pistons seem to be fine, but it runs on 4 cylinders and it snapped the cam in 3 places? I don't really care if I solve it as I am just going to replace it anyway, this is as I have zero confidence in the build plus no idea on the issue, but for curiosity sake I'd still like to know what went wrong.

I'd be careful laying blame publicly on forums. You are aware that piston to bore clearance is usually done in the centre area of the skirt? The piston is usually barrel shaped so it will taper at the top and bottom. They will always look like there is a massive gap when really that is the way it is supposed to be.

Can't say much for finger tight bolts etc but good luck with your new engine

[Rolls]

Wasn't laying blame, just saying it didn't inspire confidence seeing all these things with the motor.

Perhaps the clearance isn't that bad, but the piston slap is god awful in cold weather, sounds like a big end knock it is that loud, even when warm it rattles like hell.