1970 Big Block Timing Cover Dowel Pins

[Allen N.]

My 70 big block timing chain cover dowel pins stick out different amounts. The passenger side sticks out 0.36", and the driver side sticks out 0.16". If I install the timing chain cover on them, the driver side pin is just over flush with the timing chain cover. Is this typical?

Thanks,
Allen

[Joe L.]

Re: 1970 Big Block Timing Cover Dowel Pins

My 70 big block timing chain cover dowel pins stick out different amounts. The passenger side sticks out 0.36", and the driver side sticks out 0.16". If I install the timing chain cover on them, the driver side pin is just over flush with the timing chain cover. Is this typical?

Thanks,
Allen

Allen------


I've seen this "discrepancy" before. Whether it's common, I can't say. From a functional perspective, all that matters is that the pin engages the timing cover hole. What length of the pin "sticks out" is unimportant. If the pin does not engage the cover, then you need to pull it out enough so that it does. Why is this important? Well, the pins assure perfect alignment of the front cover seal on the crankshaft. If misalignment in this regard occurs, leaks can also occur (of course, they may occur anyway).

So, how come early 65-66 big blocks don't have the pins? You don't think that GM added the pins because things worked just as well without them, do you?

[Allen N.]

Re: 1970 Big Block Timing Cover Dowel Pins

Thanks Joe