Loud Tapping Noise From Top Of Engine - Diagnosed!

[PHATR32]

so what that mean in the way of repairs? is it possible to replace the bearings and thats it? or does the crank have to be machined etc etc?

thanks

[-==L=a=N=c=E==-]

depends on the extent of the damage, you won't know until you pull it all out.

[PHATR32]

oh ok, luckily it happened when i was about to shut it down so it was idling. i started it a few more time since while i was doing fault finding, but it was idling less than 1000rpm and it ran for 4 to 5 seconds max.

steve

[trism]

i agree. happened in my old corolla 4AGE motor.

noise came from the top of the motor. i thought that the cams were fcuked, but spun a big end... put the rod through the block lol

[PHATR32]

that said, it doesnt explain why cylinder 3 was at 30psi, and the rest at 130psi when i ran a compression test.......now that i think of it, the injector on cylinder 3 leaks a bit, so i wonder if it leaned out at some point??

i guess ill find out in a few hours time.

dam it.......

[Shaun]

If you spun a bearing, wouldnt there be bearing material in the oil. When i spun mine (i spun three bearings), there was heaps of bearing material in the oil.

Mine also sounded like the noise was coming from the head.

Either way it sucks for you; it becomes pretty f**king expensive.

Shaun.

[R34GTFOUR]

My vote goes with valve dropping

Big end bearings wont make it drop 100psi in compression, unless its got that bad that its thrown a rod out the side haha, and the oil would of been metalic

If it has just dropped a valve your extremely lucky to of only been idleing, you may get away with only new valve guides and valves.

A mate of mine's timing belt tensioner bolt snapped in his r33 (so the timing belt then came off), which also only happened at idle which was lucky, and he ended up snapped the heads of each valve. We stuck a second hand head on it and she was as good as gold.

Edited December 15, 2007 by R34GTFOUR

[PHATR32]

but if a valve dropped wouldnt the spring have come out of the top when i took the cams off?

anyways, i got the engine out and dropped the sump cover. absoulutly nothing in the oil, no metal, nothing.

the pistons look great from the bottom, and the rods look great too.

it really feels like theres something in cylinder 3. it again gets stuck when it reaches TDC.

hopefully ill get to pull the head off toomorw and find out whats happening.

steve

[PHATR32]

well i managed to pull teh head of today and found some bits of metal in the cylinder! the piston is dented and has small bits of steel fused to it, and the head it self is really dented and also had a large chunk fused to it.

I have no idea where it would have come from!!!!! ive driven it around for almost 2 years with out opening it, so im thinking it either was stuck in the piping and came loose, or its a part of the intake it self (or there abouts). either way the head is f**ked, and the piston is f**ked. what worries me is if the blocked is screwed. i dont know if the pics show much but there are tiny verticle scratches going down the wall, although when i run my nail across them i cant feel them.

the chunks of metal look roundish (like a tube), and theres nothing stuck in the cat etc.

where to now??? the money is extremely limited, and ill be looking at rebuilding it back to stock, as i cant afford forgies etc etc. (as much as id love to get some)

good old gtr's. you gotta love em..........

steve

[-==L=a=N=c=E==-]

holy shit, thats bad luck there mate....

options, just get a 2nd hand motor and putt around on it.

[dead32]

wrecker rb30 bottom end

[rb26s13]

rb26's are known to drop valve guides....

maybe possible

any reason for this and a way to fix it? my motors out.. im fairly confident thats wat has happened with mine..

[giant]

it's not bits of turbo impeller is it?

[giant]

or maybe a bit broke off the bottom of the valve guide on that cylinder?

[PHATR32]

im thinking the valve guide. that said, the broken bit is steel cause its magnetic.

ill pop the valves off on that cylinder and take a look.

steve

[PHATR32]

yep, it was definetly a guide that had snapped off. the other was cracked.

i guess a full rebuild is in order

steve