I posted a thread last week about a gear drive being loud in my 289. So I changed the gear drive out and replaced it with a good old double roller timing chain.
Somewhere in the process of removing the top cam gear of the gear drive, the dowel pin must have slipped forward. Enough that it was just barely in the cam.
Long story short... the dowel pin is bent on the end and was spinning against the cam, although it did not move the cam or the rest of the valve train as i was trying to start the motor!

Well that's not entirely true... it migh have actually spun the valve train alittle everytime the pin came in contact with the cam pin hole, just enough to open up one more valve in a different cylinder....

What the Frick do I do now!? I was so upset Saturday that I left the mess in the garage and slept for the rest of the weekend!

The heads are World product SR. I have no idea of what kind of Pistons were in the motor other then aluminum, nor do I know what clearence the valve and the pistons have/had. My builder said compression was about 10 to1. It as a voodoo cam with about .530 lift on the exhaust side.
I'm guessing the pistons had to have kissed the valves once or twice. I do know that without oil preasure, the lifters bleed down quite a bit, but not sure that would have saved the valve train. I didn't hear anything hit... the engine never started... just was turning over via the starter.
So, do I put it back together now with a new dowel pin (old one is bent on the end) and do a compression test?
Get a scope and see if I can look at the top of the pistons through the spark plug holes?
Pull of the heads and assume we need some new valves or push rods?
Pull the motor and start over?
Thoughts? Please? Good/Bad... whatever.

 

Why do you assume that the pistons hit the valves?

I would try pinning the cam and running a compression test before I pulled the heads. Don't necessarily ASSUME the worst.

You don't even have to totally reassemble the engine to do the compression test.

 

I'd fix the dowel and turn it by hand, then maybe do a compression test.

 

I'm assuming the pistons hit the valves because that is just the way my luck has gone lately.
But your right. I shouldn't just assume they did. I was thinking one of my friends has a scope that I could go in and take a look at the top of the pistons from the spark plug holes.
I'm thinking the best approach is to line up the timing marks with a new dowel pin in place and do a compression test.
Unless someone on the forum really knows for sure that the pistons would hit the valves. I have no idea what kind of clearence there is in a SB ford.

Thanks for the feedback. I like the "glass is half full" approach.

 

I would just go back to sleep...lol

Nah just be glad the dowel spun now and not 1,000 miles later when your on the highway and do more damage. Makes me think though...what should we use on the dowels to keep them in place?

 

Loc-tite works pretty well for keeping the pin in place.

NO ONE on the forum is going to know if your piston hit the valves, From your descriptions and specs I say probably not, but who knows.

By son's 351 clayed out with plenty of piston clearance, .600 lift, frankly I doubt that his engine would be an "interference engine" if his timing slipped or broke.

In my "somewhat" educated opinion I say don't worry about it..., but don't put much together before doing a compression check.

That is really what I would do.

Keep in mind, yesterdays engines are not today's engines, I don't know of ANY domestically produced engine in the 60s that would smack the valves when a timing chain went south. Your mods will make it tighter, but I honestly doubt you will have contact.

 

I hate to be the bearer or bad news but 289's are interference motors. Many years ago I broke a timing chain due to a bonehead move of my own and bent some valves. I'm not saying you did but there is a possibility.