Hey all,

I've just replaced the camshaft thrust plate on my 72 f100 302, and After I get everything tightened up, I can't turn the engine by hand (it's auto). I am now afraid to crank it over, for fear of splitting this one too. I have a new set of timing gears and a new chain, would that cause the engine to be so tight that it won't turn by hand?
Should also mention that the battery went dead as I was last trying to start it, would the starter still be engaged, and that could be holding it up? I'm about at my wits end here, as my two day job is going on 9....
thanks in advance for any words of hope
mike

 

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Turning the Engine the opposite way should free the Starter Drive.

As far as the engine Not turning easily.
The timing set shouldn't affect it UNLESS the gears were out in wrong and there is a Valve and a Piston competing for the same Space in the cylinder.
But, I doubt that is what has happened.

*Scratching head*


Dennis

78 F-150 429CJ 465,000 KM.(Original Owner)
68 Mustang 289 Sunlit Gold 80,000 Miles(second Owner)
64 1/2,260 Pre-World's Fair Mustang #8092
64 Fairlane 500 S/C,waiting for a 390 4-Spd

If The Girls Don't Find You Handsome,
They Should At Least Find You Handy!

 

What was the original problem? When you say "by hand" are you using a wrench or just your hands on the fan belt?

1977 Ford F-100
400m/c6/4:11/Gear Vender O.D.
Crane hydralic roller, forged, ported polished,Deamon,Edlebrock, yada, yada, yada
280,000 miles
Stock on the outside
modified/rebuilt everything

 

Although I am thoroughly embaressed to admit it, I once put one of the timing gears on backwards on a 302 and managed to screw up the replacement timing gauge set. It's been so long ago that I cannot remeber for sure, but I think the crank gear was the one that was backwards.

Why was the timing chain replaced in the first place? Maybe there is another problem. Also are you sure the engine was at top dead center for cylinder number one. Pull the valve cover and make sure both valves are closed.

Reggie

 

Well,
My original problem was my timing chain and gears, they were original equip, so they we pretty worked, and I was getting a lot of backfire, no matter how much I timed it in by ear, or with the timing gun. I completed the rapair, got it all back together, and then put the fuel pump on the wrong side of the eccentric, siezing up the eccntric, and forcing the thrust plat to crack.
After finding the raplacement plate i na junkytard (miracle) I have it all back together, but I can't turn the engine over to get my #1 to the top of it's stroke, using both methods of the fan, and a bf wrench on the crank bolt. It is LOCKED. As I mentioned earlier, I think that maybe since the battery had gone dead when I was last trying to start it, that maybe the started is still engaged on the flywheel, but I can't turn it backwards to get it free.
I'm afarid to turn it over in it's locked state for fear of breaking this same, out of production part.
As far as the gear itself being in backwards, the upper cam gear only fits one way, and the lower crank gear....I really don't think I've turned it around, but if I did, would that put enough pressure there to stop it from from turning?

Thanks for reading this far...

 

For the amount of time it takes why not pull the starter? It will give piece of mind by eliminating the starter binding.

Sparky

 

I've gotta agree - Pull the starter - it's easy. If it still will not turn, pull the front cover again, verify the timing gears are lined up and installed correctly, then pull the valve cover to make sure you are at top dead center on the number one cylinder. The piston should be all the way up with both valves closed. If the crank sproket has more than one key, make sure you line it up with the right timing mark on the cam sprocket.

Reggie

 

One more thought - is it the right timing chain set? I know comp cams list two different timing chains. One for pre 1972 and one after. Not sure what the differences are - maybe just the fuel pump eccentric. Make sure you are not binding on the thrust plate. Not sure what the clearance should be because I don't have my manuals with me.

Reggie

 

I think the later model timing chain is probably the 7 degree retarded version for emmissions purposes. I'm not sure what that thrust plate looks like. Could it be on backwards?

1977 Ford F-100
400m/c6/4:11/Gear Vender O.D.
Crane hydralic roller, forged, ported polished,Deamon,Edlebrock, yada, yada, yada
280,000 miles
Stock on the outside
modified/rebuilt everything

 

Hey Guys,
This one sounds "spooky". It's really not that hard to put the fuel pump in wrong, if you don't pay attention. This has a tendency the freeze the engine until you break of the arm. Secondly, If the crank gear is on backwards how do you line up your timing set marks? Do you realize that there are marks on the timing gear set? Is this a stock motor? After you remove the timing cover and check your marks, rotate the crank before you put the timing cover back on. I've never seen a starter bind like your suspecting, has anyone else seen this? Remove your spark plugs to eliminate compression, while your at it spray a little oil or WD in the cylinders, My guess is this motor has set a long time. It should not be stuck in both directions, should it? A stuck motor is a siezed motor. This is a rare situation and whatever your problem is I'll bet its simple.
Good Luck, Have Fun,
KingFisher

 

I have the timing cover off for the third time (sad,sad,), and I am sure of a couple things, and confused about a couple. The starter is not binding, and both timing gears are in correctly, as the marks line up at "12" and "6".
Now that I have the timing cover off, and loosened the cam shaft bolt, I can turn the engine over when I put a wrench on the crank bolt.
Do I have the wrong set of gears, maybe too fat, causing them to rub on the timing cover--(there are marks in the cover, but they may have been caused by earlier carelessness) or did I just get too excited in tightening the cam bolt down and locked up against the thrust plate?

Thanks for all the good advice everyone. You are helping me keep a little of my sanity!

 

O'Death
Did you remove the distributor, by chance? If the oil pump or the distributor are ceased, it would cause the cam to move forward or backwards depending on the rotation of the engine. Only a axial (forward/backwards) action can break the thrust plate. The only gear on the cam is for the distributor. The distributor drives your oil pump. A ceased oil pump is more likely than a ceased distributor. Please confirm or deny my thesis and we can go from there.
Secondly, Is the cam gear coming in contact with the block?
The cam gear could have come in contact with the cover when the first thrust plate was compromised.
Thirdly, Could you have done the fuel pump thing again?
Good Luck, Have Fun,
KingFisher

 

If the engine turns with the camp sprocket loose, sounds like it is binding on the thrust plate. Either the thrust plate is too thick or the cam sprocket is wrong. I don't know if the thrust plate can be installed backwards, on a FE it cannot. The original reason for the first failure may be related to lack of end play clearance.

 

How does the end play go out? The cam is too long? The thrust plate can be put on backwards on the 302 but it shouldn't bind on the cam, it just screws up the oiling. The plate bolts in flush with the block. It has no lip or adjusting shim. If I could see this thing, I'd figure it out in under a minute. I'm dying to figure out what's going on. O'death keep us updated.
KingFisher

 

I have removed the distributor, but I don't think that it is binding up,
The cam gear is not coming in contact with the block, The upper timing gear is rubbing on the thrust plate. You are right about the direction of the plate, It is in correctly. The previous thrust plate was broken because it had been worn from the front of the engine by the timing gear. This is where it is binding...
The question is WHY?
#1 I have the wrong cam sprocket, one that is too thick.

#2 I have lost a spacer or washer that fits between the cam spocket and the thrust plate ( I don't think this one is the prob, as my manual does not show that there should be a washer there)

#3 Instead of tightening the cam bolt down to 45 lbs per specs, I cranked way to hard and caused the seize there on the thrust plate.

I don't think I did the fuel pump thing again, becasue I couldn't turn the engine before I put the pump in.

Thanks again, I will go out and get dirty again, and check back later...