Engine Build Problem

[Bogsye 22]

Seem to have a problem with my engine build.

 

It's been a stop go effort with regard to it's progress.

 

This evening I thought I'd pop the timing belt on. The cam is in about the correct position, and I just had to move the crank a bit.

Then I noticed that when I turn the crank it seems to lock onto something. I've been very gentle in moving crank.

 

I'm certain it's not a valve issue.

 

It almost sounds like hollow clunk and as if it's at the oil pump end, when the piston (4) is nearing BDC.

 

I'm sure it's something simple and stupid that I've done. Luckily the engine is up on it's stand, so it's easy to manipulate.

 

Any ideas before I tear it down again?

 

Thanks,

 

Brian

[Daviewonder 533 3 Cars]

Could be valve to piston contact, what engine is it?

[welshpug 1,657]

you asked this on the gti6 forum a day or two ago, consensus was two bent valves if you're lucky.

[Bogsye 22]

Not me Welshpug - I'm not on the Gti-6 forum.

 

It's an 8v. D6B

Edited February 10, 2011 by Bogsye

[welshpug 1,657]

doh

 

someone posted something worded pretty much the same yesterday takes a bit to bend the 8v valves though.

 

 

how far out is the crank?

Edited February 10, 2011 by welshpug

[Bogsye 22]

I had a look on the Gti-6 forum. 'Middle dead centre'. That's a new one

 

Having slept on this I'm recalling turning the engine with just the crank, and then with rods connected.

 

That leaves just either a head issue or oil pump.

 

I've got this afternoon off, so I'll have to check it out some more.....

 

Brian.

[smithy 1]

If it was me I would rotate the cam half a turn and then try again with the crank because it certainly sounds like valve contact.

If crank moves then time it up and do same with cam you may need to do one a bit then other a bit

Until both timed,as said would be difficult to bend valves on a xu9j due to way they come out of head straight.

[allye 530 3 Cars]

I had a look on the Gti-6 forum. 'Middle dead centre'. That's a new one

 

 

Is he not referring to how a GTI6 engine's pistons are half way down the cylinders when it is all times up, due to the stupidly small tollerences.

[pug_ham 244 3 Cars]

'Middle dead centre'. That's a new one

 

He might be referring to the true tdc with the crank in the middle of the dwell position at TDC & befoe the pistons start to go on the down stroke again.

 

Graham.

[Bogsye 22]

It's official - I am an idiot.

 

Looked at the engine today with a fresh pair of eyes, and spotted the error pretty quickly. I'd put the crank pulley on the wrong way around and it was one of the webs of the casting that was catching the head of the bolt for the lower cambelt cover.

 

SO, I've written-off a perfect sump seal. Bugger.

 

On the positive side, the build of the engine progressed well.

 

One question though - the gap between the lower belt cover and the pulley seems very tight - almost like a shim is missing. Have I missed something out? Can't see anything obvious when I look at the parts catalogue, so I'm assuming it's a pretty close running fit.

 

Brian

[ALEX 98 1 Cars]

I had the same problem.

Ended up stripping half the engine down, only to find I'd dropped the M6 nut (one that holds the plastic rail for the spark plug leads to the cam cover) down one of the spark plug holes.

I hadn't noticed untill I was cranking the engine by hand to get the oil pressure up before first start up.