After rebuilding my 455 olds with my uncle, I just ran into a problem that I see as a nightmare. We went with the performer package which includes the intake, cam, carb and timing chain set. I was about to time the distributor using the compression stroke on #1 cylinder when I realized there was no compression. When I put my thumb over the sparkplug hole, it sucks rather than blow out air. I took off one valve cover and can see the valves opening and closing when the piston is in the bottom of the cylinder thus no compression stroke. The cam to crank timing must be off, but why? The only thing I can recall is that the timing sprocket that goes on the crankshaft had three key cuttings, of which only one was square. There were two others but they were round, but we used the square because the crank had a square key. Other than that, I have no clue what is going on. Any help is appreciated.

 

Did you remember to index the timing gears in the correct position before installing the cam gear and timing chain? I don't know about an olds but they possibly/probably have a small circle on each gear for indexing purposes. Maybe an olds forum would be able to answer this one.

 

Olds motors are all pretty much the same.I changed a timing set on a 350 and was the same way.I think I turned the distributor around180*.

 

Sounds like the cam is 180* out of time

 

Sounds like you used a aftermarket timing chain set. Those three different keyways in the crank gear are for different cam timing settings.There are also different markings on the cam gear that are in relation to those different positions. There should have been an instruction sheet with that timing chain set that tells you what keyway position goes to what cam gear marking. I'd say you got those marks in the wrong place.

 

03XLT4x4 Flareside, you hit the nail right on the head. This morning, I phoned edelbrock. Those three keyways- one is a circle, one a square and on is a triangle for different cam tunnings. The mistake that we made was that we used the square keyway (stock is round) and used it with the dot (instead of square symbol). Little did we know that each keyway had it's own symbol to line up with the cam. (circle is a dot, square is a bracket type and triangle is a triangle symbol. For me, this was a learning experience. I'm sixteen, but my uncle who was an experienced mechanic was too lazy ( or not all there) to take the time to figure this aftermarket setup out. I switched things around afterschool today and with a few choice words, got things together. Just a few minutes ago, a few friends showed up and we fired her up. I can't put in words the expression of what it feels like to fire that motor up...it just really felt good. It's funny how hard that halfton rocks when you feed her gas. Thanks for the imput guys. I hope this may save someone else a little bit of trouble in the future

Willie