Hello-
Maybe someone can direct me. My '76 F250 w/360 2V takes a lot of cranking and priming to start after it has been sitting for a few days. The accelerator pump works and gas is getting pumped into the carb, but it seems take a tremendous amount of priming to get it started. Warm starts are fine and even a day or two after driving it's fine. Motor has high miles. Thanks for any help.

 

Is the choke closing? Is there a good spark when first cranking.

 

Good idea-I'll check the choke. Thanks.

 

If the choke is working it might be getting too much gas?? Does it smoke black on start?

 

If you know for a fact that your engine is in good mechanical condition (not worn) then don't bother to read any further, but if you are in doubt then continue reading.

I have seen this problem occur just as you describe. Plenty of fuel (choke works) and spark is fine yet still hard to start at winter temperatures. It's too easy to blame it on the engine being flooded and that the spark is weak. Since you made it clear that it starts and runs fine when warm and all of the above details are still the same, then I would check for low compression too.

It takes good compression to get a cold engine to start fast and easy. Any engine that has lost some compression will be harder to start especially during colder winter temperatures. Most people will waste time and money trying to get a high mileage (worn) engine to start and run good because they don't realize the compression is just too low.

I am not going to diagnose your truck and say that I know that this is your problem. None of us can do that. But, if this one thing is going on with your engine then you will have to work harder to get it to the point where it will start and run good when cold.

If you do determine that the compression is indeed low, then you can at least stop wondering and guessing at where to start working on this engine to get it fixed. Okay maybe it isn't that cut and dried, but you will be on the right track. Compression is lost in several ways. Worn rings, cylinder walls, valves and seats, cam lobes (lower valve lift) and just about any part of the valve train.

Almost forgot. One other thing I would check is for PCV not working properly and any other form of a vacuum leak. The reason I mention this is because a vacuum leak causes a lean condition especially at idle and when starting. If the engine is getting too much raw air then it will be hard to start, but it would be that way all of the time and not just when cold.

I Hope this helps.