Timing issue

[canonc]

Hello all...advice gratefully received. Fitted new camshaft and with TDC set on new timing gear, and DTI on no.1 inlet follower achieved cam values. But when I fitted the crankshaft pulley the TDC mark or any of the degrees are nowhere near. Any ideas please.

[Belle427]

You sound as if your degreeing a new cam, can you explain haw you verified tdc?

[canonc]

Piston stop on number 1piston. Take reading on degree wheel on crankshaft. Then turn anti-clockwise until it touched the piston stop and take that reading on degree wheel. Add readings together and divide by 2.

[canonc]

Belle 427. Thanks you for responding to my plea. Yes...fitted a 885 cam

[Belle427]

Not sure what you mean by degrees not lining up.
Ive only ever degreed one cam on mine and used this process. I was only given one number by the cam supplier to use, this was 108 degrees.
http://www.v8developments.co.uk/technical/camshaft...

[Steve_D]

Do the same process with the piston stop but this time using the pulley/vibration damper.
If your marks do not align with the engraving on the pulley/damper then the likelihood is the damper has failed and will need replacing.

The damper is in two parts the inner section fits to the crank shaft and the outer has the markings. They are joined together with rubber in much the same way as a OEM suspension bush. If the outer has rotated relative to the inner the rubber bond has failed. On the face of it you would say no problem I'll just mark a new TDC but if you look at the back of the damper you will find some random holes. These are how the crankshaft was balanced and now is out of balance because the ring has rotated.


If you buy a new damper you either have to get the whole lot rebalanced or one of the TVR engine guys can accurately measure the holes and positions and drill the new damper to match. They will need your old damper.

Steve

[Belle427]

Just to add when I used the above method to get true tdc I slid my damper back on and it was spot on.
Lightly oil the shaft beforehand and it should come back off ok.

[blaze_away]

Steve_D said:

Do the same process with the piston stop but this time using the pulley/vibration damper.
If your marks do not align with the engraving on the pulley/damper then the likelihood is the damper has failed and will need replacing.

The damper is in two parts the inner section fits to the crank shaft and the outer has the markings. They are joined together with rubber in much the same way as a OEM suspension bush. If the outer has rotated relative to the inner the rubber bond has failed. On the face of it you would say no problem I'll just mark a new TDC but if you look at the back of the damper you will find some random holes. These are how the crankshaft was balanced and now is out of balance because the ring has rotated.


If you buy a new damper you either have to get the whole lot rebalanced or one of the TVR engine guys can accurately measure the holes and positions and drill the new damper to match. They will need your old damper.

Steve

Had this pn mine last year. Powers made me a new one drilled as per my old one.

[canonc]

Thanks guys. I also used V8 development’s information to confirm TDC and Cam timing. On fitting the crank pulley the timing marks on there are about 35 degree’s advanced. I will check the pulley thoroughly today and see if the bonding has failed!
Best wishes to you all, and stay safe

[Zener]

Steve_D said:

Do the same process with the piston stop but this time using the pulley/vibration damper.
If your marks do not align with the engraving on the pulley/damper then the likelihood is the damper has failed and will need replacing.

The damper is in two parts the inner section fits to the crank shaft and the outer has the markings. They are joined together with rubber in much the same way as a OEM suspension bush. If the outer has rotated relative to the inner the rubber bond has failed.

Steve

Dont dismiss this advice above ^ an HB letting go at high RPM can make st of much

[Steve_D]

canonc said:

Thanks guys. I also used V8 development’s information to confirm TDC and Cam timing. On fitting the crank pulley the timing marks on there are about 35 degree’s advanced. I will check the pulley thoroughly today and see if the bonding has failed!
Best wishes to you all, and stay safe

You may not be able to either see the problem or move the 2 parts.
If you have used your piston stop and proved your marking does not match the engravings then it is shot and MUST be replaced.

Steve