ET: Engine (Twin) Timing Chest Gear Meshing Adjustment

[Bill Thomas]

Hello John, I think I have used a thick washer, Like the big idler one, Between the steady plate and the breather spindle before, The small one seems too small to me, It just depends if there is room.
Like other stuff on Vin's, No two are the same !!. Cheers Bill.

 

[John Cone]

Thanks Bill. will have to wait for bits to arrive, then i will let you know how i get on.

 

[chankly bore]

I would rather say that the fixed camwheels are the datum and you move the large idler boss to suit them, then select the right halftime pinion to fill the gap.

Sorry, Bruce. I should have qualified that by saying "as to height", as to mesh, you are, of course, correct.It seems, reading subsequent posts, that John is referring to 5/16" i.d. washers or shims, so K.T.B. is the best starting point.

 

[bmetcalf]

Sorry, Bruce. I should have qualified that by saying "as to height", as to mesh, you are, of course, correct.It seems, reading subsequent posts, that John is referring to 5/16" i.d. washers or shims, so K.T.B. is the best starting point.

The discussion was about height, better reading by me next time (maybe)!

 

[vibrac]

Sorry, Bruce. I should have qualified that by saying "as to height", as to mesh, you are, of course, correct.It seems, reading subsequent posts, that John is referring to 5/16" i.d. washers or shims, so K.T.B. is the best starting point.

I believe there is a mistake in the description of the shims and washers in KTB my marked copy is not available at the moment but it was noted years ago in MPH

 

[chankly bore]

Sorry, the spacer part no. is ET162, not ET164. I shouldn't trust my memory! The error in "Richardson" is that the 3/8" i.d. shims on the followers go INSIDE, next the crankcase wall.

 

[Martyn Goodwin]

The discussion was about height, better reading by me next time (maybe)!

Next issue of OVR covers this very topic in detail

 

[davidd]

I do it like Chankly. I use the large idler as the datum. The small idler follows the large. I install the other spindles to come up to the same height by taking the shims into account. All of the under steady plate shims should be accounted for concerning their height to the underside of the steady plate, which should match the height to the top side of the two ET173's on the large and small idler.

Then, phase two is to check the cam and follower positions. To make them work properly you may have to shim the cams, which was not done at the factory, and the followers. I had to add .010" shims under both cams to line up the followers. This in turn pushes the steady plate up another .010", so you have to add shims to spindles to accommodate. That is the rub! You need some stock Vincent shims that are different thicknesses. During this adjustment you need to make sure your pinions are meshing correctly and make adjustments accordingly.

Phase three is to mount the steady plate and measure the distance from the underside of the plate to the bosses for the ET162 spacers. Cut them to size on the lathe and install. Mine were .4880", which is right inside Chankly's stated spec.

David