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AAGT150
27-03-2019, 10:41 AM
Hi I have an issue with my gold mk5 2.0 tdi bkd Engine
So I did the timing belt few weeks ago, about 300 later miles the timing belt tensioner bolt came loose out of the head and the belt came off while driving about 50 mph

Had the head off and sent to engineering shop. The diagnosed one bent valve and replaced, lapsed the rest of the valves in, checked and decoked the head. Also they helicoiled the timing belt thread In.
I put new head gasket, new head bolts etc and put it back togeather with new belt tensioner and belt.

Car now takes ages to start, once started runs very lumpy, you can hear it pinking, Nasty diesel smell from exhaust and misfires. Once engine get warm the misfire goes and Engibe is not vibrating or runing rough. But when cold or warm there is a hissing sound from head sounds like leaking injector sound.

I took injectors out checked seals etc and re tightened but no luck. The injector holes look ok and bores look good. The only thing I didn’t do was use new injector bolts. The injectors were put back in the same cylinder they were removed from.

Any help please, I think maybe more valves were bent and the engineering place only replaced one. There no fault codes and I reall don’t want to take head off again. The timing was done using proper crank lock tool but the timing marks from the first time it was done previously were off when down with the tool

Any help please thanks

Crasher
27-03-2019, 07:42 PM
Compression test first but a proper one is not easy to do. Did you check the piston protrusions at TDC were all within spec?

AAGT150
27-03-2019, 10:42 PM
Rechecked all the timing and was ok

The cams have marks and it seems the rockers are too tight. I fitted some used rocker arms from a spare head I had purchased (used). Now the rockers do they need to be compressed so oil comes out of them? It seems they are opened too much causing the valves to stay open

Crasher
27-03-2019, 11:10 PM
I have never reused them, when this happens we either fit an exchange head or wave goodbye BUT did you check the individual piston protrusions at TDC?

AAGT150
30-03-2019, 09:41 AM
Thanks for the reply

I never checked the postion protrusions as the head was not skimmed. It did not over heat and the engineering shop checked it and said it was ok.

The engine runs but from cold there is starts after 2-3 cranks ,blue smoke, diesel knock and engine shakes and vibrates. Also there is a hissing sound like like a steam train can be heard, louder when cold and heard through the airbox

Crasher
31-03-2019, 12:52 AM
The BKD runs its valves parallel to the bore so when the pistons **** the valves, that force has nothing to break or bend, just stuff in the opposite direction so valves bend and pistons/rods get crushed so if you have bent valves you have rather ****** off pistons and rods, it is standard procedure in situations like this to check for impact damage, it isn’t difficult, a flat bar and a set of cheap feeler gauges will do.

AAGT150
31-03-2019, 06:32 AM
The BKD runs its valves parallel to the bore so when the pistons **** the valves, that force has nothing to break or bend, just stuff in the opposite direction so valves bend and pistons/rods get crushed so if you have bent valves you have rather ****** off pistons and rods, it is standard procedure in situations like this to check for impact damage, it isn’t difficult, a flat bar and a set of cheap feeler gauges will do.

Makes sense, should have done it when the head was off.

Will do a compression test Tomorow see what it brings up.

The car is now chucking out black smoke when reved once warm