i rebuilt the motor (long project) and now have the truck on the road, it has about 500 miles on it so far. in the first 100-200 miles i had no problems at all, ran perfect. then i noticed it seemed a little sluggish so i figured i would pull a plug to get a reading on it and noticed my dizzy wasnt tight. of course i didnt have a timing light on me so i set it by ear and got it home.reset the timming a chalked it up to me not getting it tight and she ran great. next day same thing loose again so i lock tighted the bolt and yet again it gets loose... so i put a little weld on the hold down and hit it with a center punch hoping it would give a little traction to the dizzy and hold down, nope came loose again. what gives ??? did i some where along the way get a hold down off of a diffrent motor and get it mixed up with mine??(i had more than one but now i can only find one) i serched and didnt find anyone having this problem,am i the only one??

 

sounds like the threads on the female (block) side are stripped out, maybe try a heli-coil and tap it out... I dunno but i know the situation you describe would be annoying to have to keep retiming it everyother time you drive it

 

I agree - that's the only explanation I can think of, assuming the distributor is correct.

 

my coworker also was thinkin that was the problem but i can tighten it down pretty tight, how would be a good way of knowing if that is the problem?? i cant see down in the hole with out takin the front of the motor most of the way apart.should i try a longer bolt?? i am pretty sure the one i have it the original one. it is (from memory) about 2 inches long. thanks guys, this is frustrating!!

one more thing, steve you said if the distributor is correct,what if its the cam?? i have the original 302 distributor and an aftermarket cam (the cam has the 351 firing order) do you think that could make a problem?are the 351 and 302 dizzys different??

 

the 302 and 351 dizzys are different and cannot be swapped. the 351 used a fatter shaft because the oil pump drive shaft is bigger. the cams are interchangeable but, as you know, the firing order is different.

you are using the 302 so use the 302 dizzy.

 

Ude a drop of BLUE Loctite on the bolt.
Do not under any circumstances use red Loctite.

 

StrangeRanger,why not use red loctite??, i kinda did last week and that didnt hold.(red loctite in a blue tube)
i am going to take off the hold down on the wifes bronco and compare tomorrow, that is if i get home before dark.

 

Blue Loctite is designed for fasteners that you want to be able to remove someday. Red Loctite is for permanent installations. To remove it you need to heat it up with a torch till it breaks down chemically.

If you used red and it still comes apart you didn't prep the threads properly, which in this case is a good thing

 

The distributor has to match the block. The firing order (wire routing) has to match the cam.

The bolt doesn't need to be 2" long - IIRC, it shouldn't be more than 1 1/2". It might be bottoming in the hole before it clamps down. Can you see any witness marks on the tip of the bolt? If so, grind or cut a thread or 2 off the end, clean up the threads, & try it again.