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Will An Rb With Bent Valves Start?

chef_stagea

By chef_stagea,
in South Australia

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D_Stirls Veteran

D_Stirls

Posted
Posted (edited)

Do after you changed the belt do the gears match up with the marks when the balancer is at 0?

It will still run as you will still get some compression but it won't run well. If they are overly bent or you have knocked the head off the valve that cylinder won't fire.

Edited by D_Stirls
chef_stagea Grand Master

chef_stagea

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Madaz. See stag section for full report, I think basicly what's happened... The belt came off, I aligned the can wheels, then moved the crank wheel around to it's mark. I used a breaker bar on the harmonic bolt... I think me forcing it round( thinking it was just compression lock up... May have bent valves, not knowing what I'd done I put it back together and started it, sounded real exhaust leakish... I should have left the belt on and span it witch I wasn't aware/ think of then!

D stirls, yep all lined up, but I made it line up by forcing it to, witch I think is when I 1st bent stuff...

Do after you changed the belt do the gears match up with the marks when the balancer is at 0?

It will still run as you will still get some compression but it won't run well. If they are overly bent or you have knocked the head off the valve that cylinder won't fire.

chef_stagea Grand Master

chef_stagea

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Yeah but how am I going to a compression test? I can't keep cranking it over. Or is it ok Ish if it's not firing...? What's new valves and sleeve going to cost?? And how much time to swap lol

Yeah you really shouldn't force things

Time for the had to come off then.

Do a compression test and that will tell you the story. And then if it's low, off with the head, new valves and guides.

D_Stirls Veteran

D_Stirls

Posted
Posted

If it's lined up now then you should be able to turn it over without doing anymore damage than what has already been done. Hopefully you don;t drop a valve in the process. But without a compression test you might pull the head off and there will be nothing wrong (unlikely though).

chef_stagea Grand Master

chef_stagea

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Ok will do. So just unplug cas n go each cyl. Is it likely 2 be more than 1 cyl u rekn,

And I'll have to do all 24 valves, and all sleaves go them, anything eles? Just go stokies again? Do 26 ones fit? Likely to have piston damage?

If it's lined up now then you should be able to turn it over without doing anymore damage than what has already been done. Hopefully you don;t drop a valve in the process. But without a compression test you might pull the head off and there will be nothing wrong (unlikely though).
D_Stirls Veteran

D_Stirls

Posted
Posted

Pull all the plugs as well. Take the fuel pump fuse out and unplug the injector loom.

If you only forced it through i rotation (probably only 180 degrees) then it won't be more than 2 sets damaged (off the top of my head).

You might as well replace all the guides as you will have a fully rebuilt head then , and if you are going to chase some performance down the track get the head lightly ported while it is off. The valves will be the expensive bit (i suspect). Just to give you an idea i ordered a full set of guides form my CA for $120 + postage from the states.

chef_stagea Grand Master

chef_stagea

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Yeah ok, guess I'll give it a crack... The compression test will me how many sets are gone... I'll just pm you when the head comes off as to what I'll need, fairly upsetting cox it's my daily!!

Pull all the plugs as well. Take the fuel pump fuse out and unplug the injector loom.

If you only forced it through i rotation (probably only 180 degrees) then it won't be more than 2 sets damaged (off the top of my head).

You might as well replace all the guides as you will have a fully rebuilt head then , and if you are going to chase some performance down the track get the head lightly ported while it is off. The valves will be the expensive bit (i suspect). Just to give you an idea i ordered a full set of guides form my CA for $120 + postage from the states.

Tangles Grand Master

Tangles

Posted
Posted
a leak down test would be 100% accurate.

either way.. a breakerbar on the crank is a no no with no timing belt on.

yup means valve has hit a piston, and been bent from the forces exerted on it

as per sms Ive got a set of Neo intake/exhaust valve seats for you here, brand new

boostin32 Enthusiast

boostin32

Posted
Posted

As topic says, I rekn I've bashed up my valves, will the car start with them bent? I thaught no due to nonconpression, but the car does start... Super raggedy tho!

chef have u still got that timing belt n stuff for sale ???

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