molinafj76

I have an 85 Gt "CFI" that i got a few months back. The guy sold it to me cuz he couldn't figure out what was wrong with it. When I took it apart, it turned out that all it was... wasa broken dowel pin that keeps the timing gear in line with the cam shaft. Ok, so I replaced the pin... now a few months later, the pin broke agian! I don't want to keep replacing pins every few months! Anyone have any idea what the hell could be wrong here?

aode08

Ill be frank with you. Alot of things can cause this , like worn cam lobes, bad camshaft or bearings for the camshaft,wobbling harmonic dampner,worn timing chain and gears, the gears moving in and out excessively, alot of things. I would run through this with a fine comb, and take your time.

Something is be causing undo stress on the camshaft or the cam may be bad.


Your other option is to take the camshaft to a machine shop and gear, the have them drilled for a bigger pin, that will not break.

molinafj76

That sounds like allot of work... I have another engine that I can throw in it... pehaps thats an easier fix...

aode08

remove the dowel pin take it to the machine shop and get a titanium version

mjr46

check for slop in the timing chain.......the cfi 5.0 remember is a flat tappet cam equipped block that carries a h.o firing order on the cam...any 82 and up 302 will work as a swap just besure you know the year and firing order on the motor swapped in.....sounds like you have a a internal wear problem and if the timing gear dowl broke.. I'm suprised some pistons didn't smack any valves

molinafj76

Funny enough when it broke... at first I thought my starter was bad... but then i noticed that it was working properly... then i removed the distributor cap and tried to start it and I got no rotation... With a titanium pin, wouldn't that just start to wear out the weaker metal around it?

mjr46

with a titanium pin...if there is a prob elsewhere instead of the pin breaking the root cause will rear it's head and cause the damage there

molinafj76

Then what? Replace my Timing gear that has an elongated hole caused by titanium rubbing? . . . The pin itself is located in the belly of this beast. Behing the water pump. If I intend to fix the issue, I intend to fix it once! It wouldn't be cost effective to keep opening up myengine every couple of months...

5.0stanger

The pin should causeno wear....there should be no movement around it anyway. You could have had a defective pin in the first place. How did the dowel fit...tight, loose?

molinafj76

The pin fit snug when I put it in. There was no slop in the chain and all looked well. You're right there "shouldn't be" any movement around it... but something is still putting force on it causing it to break...