Hard Starting (cold)

[inthedirtagain]

New to I/Os......please forgive the ignorance!

I picked up an older Invader with the OMC 3.0L at the end of last summer. Had a booger of a time starting it when cold, would just crank and crank. Once started and warmed, restarts were not an issue. PO stated that he thought the fuel was not staying in the fuel line, but draining back when it sat for awhile. Is there some sort of check valve in the fuel pump to prevent this? I welcome all thoughts on the subject.

 

[Bifflefan]

Re: Hard Starting (cold)

New to I/Os......please forgive the ignorance!

I picked up an older Invader with the OMC 3.0L at the end of last summer. Had a booger of a time starting it when cold, would just crank and crank. Once started and warmed, restarts were not an issue.

I would bet that you have a choke that is not adjusted correctly, and also some operator issues.
The choke needs to be fully closed when cold and once started the "choke pull off" adjusted so it opens the plate just a bit to let air in. As it warms the plate needs to open at a rate that keeps the air/fuel mix at a proper ratio.
As to operator error, if all is working properly. You need to pump the throttle a couple times to set the choke and add some fuel to get it started. Also you can not add to much as to flood the carb. Every engine is different when it comes to this part.

PO stated that he thought the fuel was not staying in the fuel line, but draining back when it sat for awhile. Is there some sort of check valve in the fuel pump to prevent this? I welcome all thoughts on the subject.

No there is not check valve to prevent this, why would you need one? The fuel stays in the carb and can NOT siphon back to the tank. It's impossible. There for the engine will run on the fuel in the carbs for a a few minutes, cranking on the engine and the engine running will refill the carb. If you have a bad or going bad fuel pump then thats a different problem.

 

[Levinz11]

Re: Hard Starting (cold)

BY "chock" bifflefan means choke. That's the first thing I would check, too.

 

[Bifflefan]

Re: Hard Starting (cold)

BY "chock" bifflefan means choke. That's the first thing I would check, too.

I saw that after I re-read my post. LOL To early on a saturday morning.

 

[Lou C]

Re: Hard Starting (cold)

Get a can of carb cleaner and remove the flame arrester. Then spray the choke plate and linkage with carb cleaner. It's common for the choke to get sticky and then it won't close all the way
This was a part of yearly maintenance when we had cars with carbs

Also keep in mind that the choke has to be set (by opening the throttle all the way, pump it 3x) and then you manually set the fast idle by advancing the throttle about 1/3. It does not automatically set the fast idle like cars with carbs did.

 

[inthedirtagain]

Re: Hard Starting (cold)

I've owned 2 classic mustangs and refused to upgrade to EFI, so I'm no stranger to working with carbs. I'll give the choke a good cleaning and maybe look at installing a new fuel pump, too.