308 cam belt snafu

Oh man, thats horrific. But if its any consolation, its also something many of us have nighmares about and wake up in a cold sweat. First off, put down the bottle and think. Relax. Take a deep breath. I would carefully back the engine up and put everything back on the marks. Once its back in time, you can sort out your problems. Did you damage the pulleys, or the belt? If you did, are they still intact enough to rotate the engine by hand? Which bank rolled on you?

With the engine in time, the front bank pistons are in mid bore and far away from doing any immediate damage. And in the same hand, the rear bank cylinders are two up, two down. So any rotation in either direction takes them away from doing any harm. You would have to rotate 90 degrees before the front bank could do anything bad, and 180 degrees before the rear bank would start to mangle anything. Mangle. Such a nasty word to use to refer a Ferrari motor out of time.

You probably havnt hurt anything more than your pride. If you only turned the engine a little ways, the only possible damage would be if two open valves ran into each other and mangled themselves. But its unlikely. If you put any undo force into the belt, I would not even question using it, toss it and buy another. Also, inspect the pulleys carefully for any damage.

 

I know exactly what you're feeling, have been there a couple of times.

Take Paul's advice, get the marks back into place & put it back together. His analysis about the rotational margin before bad things happen is a good 1st approximation. If you bumped a valve with a piston while turning the engine (unlikely), you would have felt it. It's unmistakeable when you do it(ask me how I know), but usually does no damage as you're not putting a lot of force on the wrench & everything's moving slowly.

If you are really worried that you can't get back to where the marks are correct, then it's time to pull the cam covers & cams & make a fresh start. Put the engine on PM 1-4 & carefully reinstall the cams, line up the cam marks with the cam cap marks or degree the cams, etc.


In either case, once it's back together run compression & leak-down tests before starting the engine. Most likely they'll tell you everything's fine & you can go back to sleeping nights. Or they'll tell you the bad news before you make it worse by running the engine.

 

If you really need help, there's always some qualified labor in front of Home Depot any morning, and they don't charge too much. Most of them even have their own hammers, so they can fix anything.

 

Did you rotate the engine to get them to line up again? I ask because the marks _on the belt_ won't line up again for many revolutions even though the engine is timed correctly. You could rotate the engine the "wrong way" and the marks on the belt would line up again.

 

I dont know if your trying to disuade DIY owners, or make out they arent qualified, but no one ever got to the top without starting at the bottom. Enzo Ferrari would be quite impressed with any owner who was willing to get his fingers dirty figuring out how the car ticked, and he despised morons who didnt know how a car worked. Even if this guy messes it up, he will still be ahead financially, while having simultaneously learned great knowledge of how his car functions. The first is a gimme, the second is priceless.

But in any event, the last thing this man needs is discouragment.

 

+1

I remember the 1st time I tapped a valve with a piston on my engine, a frantic phone call to Rick Rainbolt ensued. Fortunately he got me calmed down enough to deal with it rationally. I can never thank Rick & many of the old Fchat members who helped me thru my 1st big projects. Only way I can repay them is by helping guys like Bret.

Altho I figured that Bret could look at post counts & guess who might have been around long enough to be credible.

 

easy there brett ... theres alot of guys on this post who no what there talkin about and who will guide through it ...... hail Fchat it's awesome

 

Hopefully, I can make you feel better. Back in 1992 I had my smog pump fail and it caused the cam pulley on the rear bank to jump three teeth as I was backing out of the garage. I saw smoke from the pump's belt coming out of the engine cover before realized what happened and shut it down. No damage was done and reset the cam and lived happily ever after.