Timing chain advance/retard?

[Kamloops cutlass]

A buddy once put a cam in upside down on a corvette
350hp350 it was long cranking, hard start , but it ran … not well but enough that his dad laughed and said tear it down you put the cam in upside down lol

 

[Bonnewagon]

I had a similar situation many moons go. I tried everything under the Sun to get it to start to no avail. Eventually I opened it up and found I totally screwed up the timing marks on the gears. Sometimes the gears are a tight fit and struggling to get them on results in getting them out of position. One tooth off will cause it to run like a steam engine. More than one and it won't run at all. The hardest part is convincing yourself to open up a freshly sealed and painted engine. Setting up a degree wheel is probably above this guy's pay grade and I refuse to get involved any deeper until his attitude changes.

 

[bracketchev1221]

Who can tell me whats wrong with this picture?? Chased this one for weeks.

 

[Bonnewagon]

180° off solved by rotating the distributor firing order 180°? I did that one too.

 

[bracketchev1221]

180° off solved by rotating the distributor firing order 180°? I did that one too.

Nope look closer. It may be difficult to see unless you’ve done enough of them. I couldn’t believe it when I saw it.

 

[ostrich]

Nope look closer. It may be difficult to see unless you’ve done enough of them. I couldn’t believe it when I saw it.

Top timing gear on backwards?

Nope look closer. It may be difficult to see unless you’ve done enough of them. I couldn’t believe it when I saw it.

 

[bracketchev1221]

Bingo!!! How they got the gear on backwards first, and then found a mark on a tooth to line up is amazing. This engine actually started and ran but would not accelerate.

 

[Bonnewagon]

I still don't see it but I rarely do Chevy stuff.

 

[bracketchev1221]

I still don't see it but I rarely do Chevy stuff.

That flat surface around the bolts is the thrust face that rides against the block. The 4 grooves allow oil between the block face and the gear. Usually standard 5/16” bolts with 1/2” bolt heads are used. They had to use Allen head bolt To clear the thrust surface

 

[Bonnewagon]

I get it. Yikes!