Tacho drive - more help require for a novice Healey owner.

[Cooperman]

When i bought my 59 3000 Mk1 it did not have a tacho drive housing fitted and the disty had been replaced with a later type fitted direct to the block. I now have sourced a tacho drive and a correct disty and am trying to fit it. With everything in place and the drive meshed correctly to the cam and the slots all engaged as they should be the tacho drive housing sits about 3/8" or so off the block. It seems physically too long to sit down correctly with the flange of the tacho drive against the face of the block. Any suggestions as to what is going on here would be greatly appreciated once again.... Thanks Richard

 

[vette]

Cooperman, I would say that you don't have the different shafts in the drive spindle or the tach housing lined up. If you have the shop manual, look at the Section B. But if you pulled the drive spindle out of the oil pump housing you might not have it back in all the way. When the dog and slot are lined up it will slip right in. If you turned the crankshaft while the spindle and distributor were out, then you will have to re-time the engine. Again in the book, but centually put the # 1 cylinder at TDC on Compression stroke, put drive spindle in so that the slot is in a line as if pointing to the 2 oclock position and then also at about the 20 till 2 position. This slot is not centralized. It creates two segments, the top segment is larger than the bottom segment. With smaller segment on the bottom everything should line up and the shafts will all slide together. Then bolt the distributor clamping plate to the tach drive housing, but leave the distrutor tighting yoke loose enough to turn the distributor. I forgot to say earlier that with the #1 cylinder at TDC on the compression stroke, the notch in the crank pully should be lined up with the pointer on the timing chain cover. So now with all this stuff lived up, turn the distributor till the points just open. tighten the distributor down. this then is a good static timing and the engine should fire right up. Once engine is warmed up and idleing at anything less that 1000 rpms, 700 would be good, then set timing dynamically at about 12 degrees before BTDC. Dave.

 

[Cooperman]

Thanks for that. What I have discovers is there's a small slotted adaptor plate clipped to the top of the dizzy cam drive dog that allows a later (25D) distributor to be used which bolts direct to the block with no tacho drive housing. Once removed it all assembled perfect. Thanks for your reply though..... Onto the next jobs, put head on, manifold on and engine in, I hope! Richard