Thread: 250 still wont run, still just as stumped

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New carb, points and ignition components from rotor to spark plugs. No change in how it operates(start, stall after a max of 3 crank revs). Far as I can tell the cam hasnt jumped time, see attached picture. For more information on the vehicle, go to http://clubhotrod.com/forums/showthread.php?t=23931 . Still want to know why it wont run so I can fix it, any input is greatly appreciated. Thanks in advance

sounds like you need a 292 , to bad your far away from me

If all it needs to run is fluids, fuel and 12V, I'm interested in trying to ship it. I'll be in the phoenix area october anyways, which isnt too far from fresno. Problem is my parents wont let me drive down there...


It does have juice with key in run, voltage at coil reads 12V when points are closed. problem is, when I hand-turn the crank, it takes 8º to elicit a reaction in the rotor, it should turn instantly. also, sometimes ittl just spit fire out the carb instead of kick, and still other times it just cranks and cranks and cranks. I'm thinking the gear that drives the distributor on the cam is missing teeth?

pull the distributor and look at it... sounds to me like you either have a nylon or brass gear against a brass or iron gear...... that'll cause a big mess...

Originally Posted by 379

New carb, points and ignition components from rotor to spark plugs. No change in how it operates(start, stall after a max of 3 crank revs). Far as I can tell the cam hasnt jumped time, see attached picture. For more information on the vehicle, go to http://clubhotrod.com/forums/showthread.php?t=23931 . Still want to know why it wont run so I can fix it, any input is greatly appreciated. Thanks in advance

i dont see nothing in that pic. that tells me its in time. where are the dots?

I'm not sure but I think the distributer gear is held in time with a pin. Maybe sheared???

those appear to be the time marks, which is why I'm thinking the same thing. I pulled the dist when I saw the gears and the gear on it appears to be intact.

The gear probably is intact There is no reason for it to be broken. put the gear in a vice and try turning the rotor shaft. use a pair of chanel locks with a rag or nylon grips. If the pin is sheared it will move. if it just feels tight by hand the sheared pin can hold because of excess metal being rolled over. This realy is the only ting that makes sence. Hope I'm wrong
Good Luck
Charlie

There is one other thing. You could have a sheared key on the cam or crank The marks would still be in time but not the shafts??? just a thought

Originally Posted by 379

No change in how it operates(start, stall after a max of 3 crank revs).

Are you saying it starts and runs while the key is in the start position but it dies when you let the key go back to the run position?

Forgive my ignorance, but does your car have an ignition (ballast) resistor that is separate from the coil and mounted maybe on the firewall? It's usually made of ceramic or porcelain. If it does, see if it is cracked or broken. If it is, splice the wires together. If it runs it should get you home, or to where you can buy another one, but don't go far because the full 12 volts from the battery will be going through the coil and can fry your points.

jim

Originally Posted by DennyW

The reason I asked if that was the marks is because the picture was blurry, and it was real hard to see it. You being there, you should be able to see it clearly.

The reason I took the picture in the first place is to find the marks. between the grease and the angle, I couldnt see the marks on the crank gear. I just pushed the cam up against the radiator and snapped a shot to ID the mark.


@ Big Tracks:
I changed that when I overhauled the ignition from rotor-up. Odd thing is, when I first bought the truck, I found 12 of either them or condensors laying in the bed with varying amounts of rust on them. Perhaps this thing eats resistors? Idunno, but it's got an HEI distributor on the way so that problem will be avoided. And if the old one does check out as repairable or good, I'll have a spare to stick in the glovebox incase something goes screwy


@cffisher:
the crank key is intact, the key on the cam is unknown. any way to check without yanking the gear?

If the resistor is broken it's easy enough to see, but take a close look at the part that looks like a skinny spring about two inches or so long that provides the resistance. It could be burned or damaged.

I learned about faulty resistors several years ago when, after I had changed nearly everything on the dang truck but the body, my service station operator told me what my problem was.

Jim

Ive got two chevy 250's in my garage, one is a nova engine and the other is a gmc engine. i got the nova engine bc i wanted a rebuilt carb and a guy sold it to me for 50$, the only catch was i had to take the 250 attached to it. I ve run the gmc engine with the 3 speed it had. It felt too much like a tractor (youre gonna know that youre in a 30+yr old truck). If you like driving over 40mph you are going to hate that 250 3-speed combo. my opinion, junk the 250...buy a small block, it sounds cliche but it really is true and maybe a better tranny....i got a small block 307 from my parts truck (always a good idea to have a car to donate some parts, in my case a '68 chevy c10) and i got a rebuilt T5 from a guy for 500$....should work well in my 1968 gmc counterpart to your c10. that three speed was ridiculously low for modern roads...sorry i was just thinking back to when i drove that combo.


then again...if you want a proven 250 inline i got two over here in florence, sc. shoot me an offer if you want one (or both) (you can interchange all that stuff you put into your busted one)