[engine_work] Time For Another Supercharged Gti6 205

[James_m 0]

Isn't this a common problem with the gti6 engines where they randomly they tapping for no reason? I'm not familiar with this myself but sure its been mentioned. Perhaps a look over on the 306 forum might reveal more answers.

[tidypug 5 2 Cars]

thanks guys, good thinking. TOmorrow i'll get her in the garage to check things out.

[welshpug 1,622]

I would stick some fresh oil in, especially if it goes when the pressure builds

[tidypug 5 2 Cars]

Well it doesn't look like good news

Had a look at the timing and its waaaaaaaaay out. The cam timings fine but the crank is out by quite a bit, something like 3-5 teeth on the crank. The belts nice and tight so I guess the crank pulley has failed allowing the timing to move, bugger.

Now the thing is I've done a compression test and got 240 psi across the board, so if some valves are bent they can't be that bent.

What do you think the chances are of me getting a new bottom pulley, re-timing her back up and everything being ok?

[Toddy 7]

Well it doesn't look like good news

Had a look at the timing and its waaaaaaaaay out. The cam timings fine but the crank is out by quite a bit, something like 3-5 teeth on the crank. The belts nice and tight so I guess the crank pulley has failed allowing the timing to move, bugger.

Now the thing is I've done a compression test and got 240 psi across the board, so if some valves are bent they can't be that bent.

What do you think the chances are of me getting a new bottom pulley, re-timing her back up and everything being ok?

 

 

There may be nothing wrong with the timing, as it may have been set up with a knackered bottom pulley/rubber joint failed during service, although it would be wise to replace the pulley. The knackered bottom pulley may simply give you the impression that the timing is out.

 

 

 

1) To check align the cam pulleys with their respective timing holes, the pistons should be midway through their stroke.

2) To check this, remove the spark plugs, then place a cable tie down through the spark plug hole until it rests on the piston, where the cable tie protrudes above the coil pack hole, mark the cable tie here, compare cylinders 1&2 or 3&4 the height from piston to top of coil pack hole should be identical if it is timed correctly.

[tidypug 5 2 Cars]

just tested with a cable tie. With the bottom pulley at the timing mark pistons 1 & 4 are tdc and 2 & 3 are bdc or as close as can be.

Am I right in thinking this isn't good?

[Tom Fenton 1,525]

No. It just means that the bottom pulley which drives the alternator belt etc (and more importantly has NOTHING to do with the cambelt) is knackered and has slipped round on the damper rubber.

 

Turn the crank round until the timing holes on both cams line up. Then try the cable tie trick again. You should then find the pistons are level.

[chrisj21 2]

If the bottom pulley is knackered (recently in your possession) it just means you can't re-time it using that pulley, it wouldn't as Tom says affect the timing if it had slipped during running.

 

I'm using one of Miles's alloy bottom pulleys.

[tidypug 5 2 Cars]

ah i see, sorry its just me being a bit thick, think I'll still get an alloy bottom pulley

[tidypug 5 2 Cars]

and another thought, the supercharger is powered by the bottom pulley. Could my missing power be because of the knackered bottom pulley?

[M@tt 77]

quite possibly!! if the outer section of the pulley is slipping then it could not be spinning the charger properly although i would have expected it to maybe have shat the pulley out by now if the rubber had completely disintergrated and it was constantly slipping

[Rolando 10]

rich w sells them on the 6 site as well. think there £65 delivered. thats who i got mine from

[tidypug 5 2 Cars]

Its gone up a bit, I've just ordered one from him. Came to £70 delivered

[welshpug 1,622]

they were £90 + post, until someone decided to make their own and undercut him by £20

[Alastairh 47]

TBH, im surprised you haven't upgraded it already what with a charger running off it aswell. For the crank to by 5-6 teeth out, i dought it would run / well atall.

 

Al

[tidypug 5 2 Cars]

I put 4 tie wraps down the spark plug holes and aligned the cam's with the timing marks. Thankfully everything seems to be about right.

[Toddy 7]

I put 4 tie wraps down the spark plug holes and aligned the cam's with the timing marks. Thankfully everything seems to be about right.

 

Jamie

 

It is best just to use one tie wrap, where it protrudes from the coil pack aperture, I mark it here with a small cut, then compare/make sure the height is identical on the other cylinders.

 

Have you changed the oil?

 

Cheers

[tidypug 5 2 Cars]

I have yes, but haven't started it yet as I've decided to swap the box while I wait for the new pulley.

[tidypug 5 2 Cars]

The new pulley arrived, when I compared it to the old one the timing hole was over 45 degs out. With the new item fitted I checked the timing again and all is well, thank f***k!

With some new oil in I ran the engine up hoping the noise would go away, to a degree it has but it seems to come and ago as it wishes . So I'm not sure what it is, could it be a duff tappet? could it be a leaking exhaust manifold could it be a slightly bent valve? I dunno.

With the new box on I took it for a quick test drive, all seeemd fine until I couldn't change gear. It felt like the clutch cable had snapped but its still attached and pulls the release arm as it should. With the engine off I can select gears but with the engine running theres no chance.

So as usual nothings as straight forward as it should be. The cars back in the garage awaiting for me to get the motivation to take the box out again. Bloody car!

[All Praise The GTI 3]

i know how you feel mate,if its not one thing its another grr

[tidypug 5 2 Cars]

I wipped the box off tonight to see what the problem was.

I think that the release bearing must have partially come adrift from the release fork causing the release bearing to push on only part of the clutch. I put this down to being a bit brutal while fitting the box as the engine doesn't allow much movement with the rs200 top mount fitted. So as the engine doesn't drop very much getting the gearbox on causes the gearbox mounting bolt to catch on the inner wing.

Here's what I found in the box.

[tidypug 5 2 Cars]

Got the box back on again, took it for a test drive and all is well with the gear change.

 

Now back to the original problem, the rattle is very definately back and decided to record it this time.

http://smg.photobucket.com/albums/v310/tid...=20100621_1.mp4

Any one any ideas whats making the noise?

[guffe 2]

Any one any ideas whats making the noise?

 

Hydraulic valve lifters.

[welshpug 1,622]

sounds like a "tapper"

[tidypug 5 2 Cars]

put this thread up on the gti6 forum, looks like its could be the big ends

Looks like my summer of enjoying the car are out of the window. As I recently bought a house, the car will be dumped at my parents until I start to feel the love for the thing, it may be some time!