So I just did a Timing chain on my 351C. All said and done, no leaks and truck starts but I've been unable to tell if I've fixed the problem of my small backfire issue. What I've gathered is that I've 'shimmed' the pully? installed it wrong. It seems to be slightly cocked upwards and is rubbing against the water pump which is in turn smoking pretty heavily for obvious reasons. I'm going to pull the main bolt again and try to reinstall the pullys and see where I made my mistake. Any tips on how to make sure I do not do this again would be great. I used an impact gun when tightening down the main bolt, did I maybe tighten it down too much and took away my clearance I would have had? During the re-install I thought I confident that everything was in the correct position, i tightened down my main bolt with a socket wrench and then pressed the dampner back into position by putting the impact on it.

I am not a mechanic. This is not my job lol. But I'm giving it my all here, and though I'd like to put this truck to rest, I just can't stop when I'm so close to finishing it.

PS - When I installed the timing set, the engine was at 'B7' on the dampner. From what I understand this is TDC? It also reads 0 on the markings. I as well put the engine at TDC with a flathead in the first port to double check this mark and it was TDC from my reckoning. However when I put the new set on, the dots did not match up perfectly. My manual shows the teeth in the gears pointing directly at one another and the dots lining up. So I did this by turning the crankshaft backwards slightly. This brought the marks inline and the teeth matched my diagram from the book. Once I put it all back together, the timing mark read one line after B7. So on my Dampner it looks like this.

* (this being my starting position, 1 mark after B7)
ATC 3|0|||2|0|||1|0|||B7....ect, ect |||BTC


Thank you for any help. You guys have all been a godsend during this rebuild.