351 ENGINE INITIAL TIMING???

Sounds like a new timing chain and gear set are in your future.An easy test is pull the dist. cap and roll the motor backwards. the rotor should turn as soon as you roll the motor . Any lag will tell you the degree of slop in the chain,,,,,,,,,,,
        Boat dr

Is it off permanently or does it fluctuate back and forth? Could just need new advance springs. If the springs are worn out or plates sticking the advance may not be returning to your 10 initial.

I'm at a lost for the set screw you are talking about. There should be a bolt holding the clamp to the manifold that holds the dist in place rotationally.

i popped the cap on the distributer and turned motor over backwards while watching rotor. rotor did not move immediately. i got a hair or so turn on the wrench before it moved. is this satisfactory? also, should i be able to move rotor back and forth in a rotational motion with my hand about an eighth of and inch or so both ways?

yes.. i set the time at 10 degrees and after running it the time is around 5 or so. what would be the best course of action to take at this point?

76'SN wrote: yes.. i set the time at 10 degrees and after running it the time is around 5 or so. what would be the best course of action to take at this point?

That doesn't make any sense, you're saying that everytime you run the engine the chain is stretching 5 degrees. I don't see how that can be unless it's totally trash and I think you'ld see more movement when you checked it earlier if it was.

I still would check the distributor first like boat dr says, could be the pin that holds the gear on is worn or broken and the gear is moving enough to throw your timing off. If the dist checks out then throw a good chain on it.

should bother checking the advance spring? i really didnt want to unless necessary simply because of all of the parts removal to get to it. but more than likely a new timing chain and gears would correct this problem, right?

also i meant to add, with this boat being a 76' is this safe to blame normal wear for this problem? i figured a chain would to a pretty good job of maintaining its setting. what would cause the drive gear to shear. didnt think there was enough play in them to get loose enough to wear.

76'SN wrote: alan, you mention the factory gears may be nylon. are the replacement gears be made of nylon as well? i dont mind investing the money. i am definitely going to check it out. is there a site where i can order this stuff? and is there any diff in a normal 351 gear and chain set since these motors are reverse rotating?

Once again Summit is good for your gear set, I put a Cloyes in mine, don't have any experience with Summits set but most of their house brand items are made by the big guys anyway so it's probably fine.

A good set will have steel gears, timing chain wear is a fact of life. I put 750 hours on a 351 PCM and thought it was dying, replaced the timing set and brought it back to life.

Make sure you get your gasket set at Skidim not the local auto parts store. Call and tell them what you're doing and they'll set you up.

i found these two items from summit. cloyes chain and gear set along with timing cover gaskets. how does this look? should this get the job done and is this one the double row like you referring to?
http://store.summitracing.com/partdetail.asp?part=CLO%2D9%2D3535X9&view=32&N=700+150+4294840125&appfilter=1#Application
and http://store.summitracing.com/partdetail.asp?part=FEL-TCS45008

It sounds like the clamp holding the dist is screwed up and not working right.

Grap the whole dist cap and try rotating it if it moves then I'm right.

well if the chain is shot then everthing else isn't far behind so you might as well re-build the whole thing.

That timing set looks fine. A Comp or Crane double roller for ~$40 would probably work, but $85 for a Cloyes True Roller isnt bad- thats where my money would go.

76'SN wrote: if i hold the gear and turn the rotor with my other hand it has a springing action one way that moves almost 1/8in in that direction but springs back when i let go. is this normal?

Normal, thats just your centrifical advance thats why is only in one direction.

am i going to need a puller to remove the harmonic balancer? i am picking up a cloye gear set and chain with all gaskets tomorrow.