Cold Start Issues

[JMUBullnose]

Hello everyone - thanks for the assists so far! (Still dialing in the OD issues)

This morning I was having issues cold starting the truck. I pressed the accelerator pedal to the floor to set the choke and eventually got the truck to turn over. However, it died within 3-4 seconds of starting - feathering the throttle did not help keep it alive. After I restarted I feathered the throttle to hold the idle and was "off to the races" after I let it warm up for a minute or so.

What do I need to look at or adjust to try and figure this out?

 

[Gary Lewis]

It sounds like the choke isn't coming on far enough when the engine is cold. On the 2150 page, on the TEK At Large tab and then the Theory & Operation tab you'll see the choke cap on the passenger's side of the carb. The best image is at the bottom of that page. There are three screws that keep that cap from turning. If you loosen them you can rotate the cap, and I think that you rotate counterclockwise to bring the choke on more, although the direction is probably noted on the cap. There is a mark on the cap and a set of marks on the carb. I'd turn the cap two notches toward the rich side, snug the screws down, and try that.

But remember where the cap was originally sitting if you have to put it back.

[JMUBullnose]

It sounds like the choke isn't coming on far enough when the engine is cold. On the 2150 page, on the TEK At Large tab and then the Theory & Operation tab you'll see the choke cap on the passenger's side of the carb. The best image is at the bottom of that page. There are three screws that keep that cap from turning. If you loosen them you can rotate the cap, and I think that you rotate counterclockwise to bring the choke on more, although the direction is probably noted on the cap. There is a mark on the cap and a set of marks on the carb. I'd turn the cap two notches toward the rich side, snug the screws down, and try that.

But remember where the cap was originally sitting if you have to put it back.

Thanks so much Gary! I'll take a look this afternoon when I go back out to the truck!

The choke issue wouldn't also affect engine performance when making hard turns would it? Many times I've gone into a turn (coasting) and then go to apply power as I'm exiting the turn and the engine will stumble slightly like it's not getting enough fuel but then it catches up and all is well.

[Gary Lewis]

Thanks so much Gary! I'll take a look this afternoon when I go back out to the truck!

The choke issue wouldn't also affect engine performance when making hard turns would it? Many times I've gone into a turn (coasting) and then go to apply power as I'm exiting the turn and the engine will stumble slightly like it's not getting enough fuel but then it catches up and all is well.

Yes, the choke coming off too early could easily cause the engine to stumble when you go from coasting back to power. But it would only happen while the engine was still warming up. And it wouldn't be dependent upon hard turns.

So, if it really is because of the turn then you probably have a low float level. That means there's not enough gas in the bowl of the carb and on a hard turn the gas can be pushed to the side and away from the main metering jet.

I'd make the choke change first, and if that doesn't solve the stumble then it may be time to check the float level. And we can talk you through that.

[JMUBullnose]

Yes, the choke coming off too early could easily cause the engine to stumble when you go from coasting back to power. But it would only happen while the engine was still warming up. And it wouldn't be dependent upon hard turns.

So, if it really is because of the turn then you probably have a low float level. That means there's not enough gas in the bowl of the carb and on a hard turn the gas can be pushed to the side and away from the main metering jet.

I'd make the choke change first, and if that doesn't solve the stumble then it may be time to check the float level. And we can talk you through that.

Awesome.

I was wondering if the float might be the issue (after reading the rangerstation guide on rebuilding). A rebuild is likely in order for the whole carb anyway!

Gotta say - love this forum!

[tjmac]

It sounds like the choke isn't coming on far enough when the engine is cold. On the 2150 page, on the TEK At Large tab and then the Theory & Operation tab you'll see the choke cap on the passenger's side of the carb. The best image is at the bottom of that page. There are three screws that keep that cap from turning. If you loosen them you can rotate the cap, and I think that you rotate counterclockwise to bring the choke on more, although the direction is probably noted on the cap. There is a mark on the cap and a set of marks on the carb. I'd turn the cap two notches toward the rich side, snug the screws down, and try that.

But remember where the cap was originally sitting if you have to put it back.

I'm having the same cold start issue that's described here. Takes a while to get it to turn over, but once it warms up, I'm good for the rest of the day.

Gary- I'm guessing the advice you gave here would still hold for me as well?

 

[Gary Lewis]

I'm having the same cold start issue that's described here. Takes a while to get it to turn over, but once it warms up, I'm good for the rest of the day.

Gary- I'm guessing the advice you gave here would still hold for me as well?

Maybe. I think the original problem was a stumble just after starting, but you say it "takes a while to turn over". To me "turn over" means for the engine to actually start turning when you engage the starter, but I'm guessing that you mean for the engine to actually start running.

But you may not be familiar with the starting procedure for an engine with a carb. There's a linkage in it, called the fast idle linkage, that causes the throttle to be opened slightly when the choke is set. But when an engine cools off with the throttle closed the fast idle linkage cannot move until you open the throttle a little bit. And when that linkage doesn't move the choke cannot set.

So the first thing you do before trying to start a cold engine that has a carb is to depress the throttle a little bit and then release it. That let's the choke set and it squirts a bit of gas into the engine via the accelerator pump.

Try that and let's see if it starts easier cold. If not we can adjust things.

[ratdude747]

I'm having the same cold start issue that's described here. Takes a while to get it to turn over, but once it warms up, I'm good for the rest of the day.

Gary- I'm guessing the advice you gave here would still hold for me as well?

Maybe. I think the original problem was a stumble just after starting, but you say it "takes a while to turn over". To me "turn over" means for the engine to actually start turning when you engage the starter, but I'm guessing that you mean for the engine to actually start running.

But you may not be familiar with the starting procedure for an engine with a carb. There's a linkage in it, called the fast idle linkage, that causes the throttle to be opened slightly when the choke is set. But when an engine cools off with the throttle closed the fast idle linkage cannot move until you open the throttle a little bit. And when that linkage doesn't move the choke cannot set.

So the first thing you do before trying to start a cold engine that has a carb is to depress the throttle a little bit and then release it. That let's the choke set and it squirts a bit of gas into the engine via the accelerator pump.

Try that and let's see if it starts easier cold. If not we can adjust things.

... As was documented in this article/video:

https://www.garysgaragemahal.com/correct-cold-starting-procedures.html

(Yeah, it's a GM video, but the principle applies to all carbed cars/trucks that were made in the last 60+ years).

[Gary Lewis]

... As was documented in this article/video:

https://www.garysgaragemahal.com/correct-cold-starting-procedures.html

(Yeah, it's a GM video, but the principle applies to all carbed cars/trucks that were made in the last 60+ years).

Thanks, Larry. I'd forgotten about that video.

Boy, is that announcer deadpan! It is almost painful to S.L.O.W.L.Y. listen to him.

But he is right. And he explains all of the details I was trying to discuss plus some that I didn't - like the choke unloader when you press the throttle to the floor.

[tjmac]

Thanks, Larry. I'd forgotten about that video.

Boy, is that announcer deadpan! It is almost painful to S.L.O.W.L.Y. listen to him.

But he is right. And he explains all of the details I was trying to discuss plus some that I didn't - like the choke unloader when you press the throttle to the floor.

Thanks! Really helpful.