Hydraulic Chain Tensioner for a Cosworth V6

[GBGaffer]

Hi all,

Can anyone help with instructions as to how to fit a new hydraulic chain tensioner to the Cosworth BOA V6. The old tensioner has a 'toothed' internal sleeve (this is the bit that broke), which appears to be able to 'pre-tension' the piston. I assume that the point of this is to allow the part to be fitted with the internal spring compressed and then released when in position. Has anyone done this as I don't want the new part to break as result of incorrect assembly.

Thanks in advance

Graham

[James MK]

Just done a search for a similar problem! Did you have any luck with this?

[Boosted LS1]

Yep, look at the tensioner in your hand and screw the nurled/notched section back into the housing so it's at it's shortest length. Also, note the size of the allen key hole in the middle and find an allen key to suit. Then install the tensioner into the head making sure it engages with the blade properly. Once installed, remove the grub screw, insert aforementioned allen key and turn which will release the internals of the tensioner. Voila. The allen key will only turn one way to release the gubbins. You can check which way before you fit the assembly into the head, ie do a dummy run

Edited by Boosted LS1 on Saturday 26th July 21:38