Nash Metro w/MGA 1500 discrepancy...

[doc50]

Hoo-boy, am I confused. My Nash book and my experience setting up cam gear/crank gear orientation on other motors tells me to have the dimples line up, close together.

HOWEVER

A video by John Twist from (sadly now defunct) University Motors showed how the cam gear should be 180 degrees out from that in order to be on compression stroke, #1 cylinder.

In other words, if I line up the dimples close together, it looks like it's on #4 compression stroke, ie; #4 rockers are loose, #1 are tight. From what I saw after an hour of screwing with it, he's right. Just looking to you out there who are more experienced to confirm that I need to line up the dimples but with the cam gear dimple AWAY from the crank gear dimple.

Why would they design it that way, anyway????

Why would they design

Thanks

Thom
1958 Nash Met

 

[dklawson]

If I understand your concern, this is not a discrepancy.

On A-Series engines, with the timing cover removed and the timing pulleys oriented "dot-to-dot", the engine IS sitting with #4 at the start of its firing stroke. It is just the way it is. I would not be surprised (and actually would expect) that since the B-Series engines are from the same parent company they would be the same.

That said, your concerns are not unique. I have seen a lot of A-Series engine owners question the timing pulley vs crank orientation. I have no idea why the factory did it this way.

 

[doc50]

I thought about it and soon came to the conclusion that no matter what, I have to time it from #1, so that's what I did. Meanwhile, I'll keep looking around to see why they did it this way. I'm a bit obbsessive that way.

Cheers.

Thom