ok, here goes. have a '73 f250, 460 auto. have hot start issues. replaced solenoid(needed it anyway), starter(it was going when i bought the truck), new 4 ga wires from battery to solenoid, then solenoid to starter, and new clamps. the ground looks ok, from what i can tell. if the truck is hot, it wont turn over, no matter where the timing is set. i cant figure this out. it used to be it would turn over real slow when hot, then finally start, but now nothing. any suggestions. i took the batt to napa and had it tested and the guy said i got 12 volts and 750 amps output, should be plenty for a stock motor. i am wondering if the rebuilt starter is hosed, i think i am gonna take it off tomorrow and take it to get load tested, but past that, i dont know what else to try.

thanks in advance.

jamie

 

take your ground wire off the block, clean, and reinstall, then take your starter off, clean the face where it bolts on, and re install, then try starting it. if that fails, try hooking booster cables direct to the starter. ( hot to the wire terminal, and ground to the mounting ear...

 

unfortunately a lot of the rebuilt starters are junk. if you got it from a reputable parts place they should replace it. also try to place some kind of heat shield between the exhaust mainfolds/headers and your starter. I have never seen one for this specific application but you can adapt or modify one from another vehicle or fab your own.

 

When was the last time the timing chain and gear's were replaced? It may very well be that it still has the old phenolic cam gear and it is worn away. Check and see how much play is in the dizzy rotor when turning the crank bolt back and forth with a socket. If it turned over very slow with the old starter and still does the same or worse I would look else where for the problem.

When you said it used to turn over slowly and then start did it sound like the motor was jerky, or sound like a weak battery, while trying to crank it over in the starting mode b4 it started?

 

jerky, it would speed up slightly, then lag back down to almost nothing, the a few seconds later it would speed up a little then start, but it has been that way with both starters. i replaced it becuase it quit engaging the flywheel completely, and didnt want to mess with it. not sure on the age of the timing set though, because i have never had the front end of the motor apart. guess that is next. i will try the play check in the morning with the crank bolt and dizzy and see where it goes from there.

i will also clean the ground and install the one between the cab and block that i bought today and see if that helps.

thanks for all the quick replies, and if anybody has other suggestions, keep them coming.

 

I'd suspect the starter. Have you tried banging it with a hammer while trying to start the motor?
Use to have an old '62 unibody F100 that developed a bad starter on a trip from W.V. to Texas. (this was around '90). It would start cold but once it got hot I'd have to slide under the truck and start banging on the starter while my wife hit the key.(lost the truck in the divorce... Yes I miss that TRUCK !!) This process got me where I was going, even in a driving rain in Lafiette Lousiana.
Tony

 

I'd think twice about the old "hammer to the starter" trick. If it a newly rebuilt starter, it most likely has ceramic magnets in it and all you will do is break these magnets and kill the starter. I am suffering the same problem and am trying to figure out how to resolve and think it is related to timing. I pulled the distributor out to clean and check it, discovered that the vacuum advance is shot, also am replacing plugs and wires. Pulled a couple of plugs and the gap had widened to about .60 instead of the recommended .44 and the wires are in pretty rough shape. I already replaced the coil so I am hoping that all of this will solve the problem. WIll post back when it is done.

 

well, i chopped and cleaned the ground cable, and installed a new ground strap between the cab and block, and most of the gremlins seem to be gone, but i still think i have a small timing issue, like the chain is getting loose and sloppy. i will post more about it when i get it fixed.

 

Kermit did you try the socket on the crank? It is a pretty good way to tell if the timing chain and gear's are screwed up.

 

not yet, got busy and only got to the electrical before the wife tracked me down, but i am gonna try to get to it tonite, but not sure if that is gonna work.