I've got an '81 GMC Jimmy. Originally had the 5.0L V8 Engine but that was swapped out for the 6.6L V8 engine. Thats all I know about that as it was done by the previous owner but a good mechanic friend of mine has looked it over and confirms it was done professionally so hopefully that doesn't play a part in this issue.

So the problem is, when starting the vehicle with the engine cold, say the next day, it seems to take almost a minute before the engine kicks into life. Now, I'll admit, my previous vehicles before this were all fuel injection models so I'm used to just turning the key and the vehicle starting mostly straight away. So is there a procedure for starting a carb. vehicle?

What worries me is that the weather here is around 20-30'c at the moment but within a few months they'll be a negative in front of those numbers and the truck might not start at all...

What could be causing this? I'm probably going to take it to a mechanic to have it fixed but I'd atleast like to have some info for them and an idea of expenses before I get there.

Thanks in Advance.
Jamie

 

Some carbs can be more finicky than others.

For my '74, I pump the throttle three times if the engine is dead cold. Starts almost instantly and sets up on high idle.

If the engine is hot and was just running, I just turn the key without touching the throttle at all and it will start nicely.

If the engine is hot, but it has been a little bit since it was running, I hold the throttle wide open and crank it over. This sometimes takes a bit of cranking at times.

I have never had this truck fail to start for me even though it has sometimes seemed like it would not. By far the most problematic starting condition is the hot condition where the truck has sat for 20-40 minutes.

 

Hey man.
So I tried what you said with the pressing the pedal 3 times before cranking and it sounded like it wanted to start and then I had to wait the minute for her to fire up.
Next I tried 5 presses with the same result.
Maybe the carb needs a tune? What do you think?

 

It is very possible. It is also possible that the carb just needs a good tear down and rebuild. They really are not all that complicated when you get into them. Just make sure you pay attention to where all of the little brackets and rods go.