93 fast strike 150 - fuel delivery issue (primer solenoid leak)

[tritico]

recently got all carb kits installed, thanks to some previous advice from this forum...Thanks guys!
So... went to start the motor today, and when I primed it...the solenoid squirted fuel out the front of it. After close examination, it looks like the red lever is cracked. The motor did start and run after pumping the fuel bulb, but would run about 30-45 second and then die. It seemed to run with a little miss though. The motor would run with no miss, and would not die as long as pumping the fuel bulb and keeping it tight.
I know its a fuel delivery issue and my question is this.... could the fuel leak on the primer be the culprit? I was curious because it only leaks fuel when the primer is engaged via key....not after the motor has been started and running. Thanks in advance.

 

[daselbee]

Re: 93 fast strike 150 - fuel delivery issue (primer solenoid leak)

No it cannot be the culprit. It will drip there when pressing the key in, or when the red lever is turned to manual position.

A motor that starts and runs only while pumping the primer bulb generally has a fuel pump problem.

But, it usually takes longer to die (run out of gas in the carb bowls.) Usually they will run for 4-5 mins at idle with the gas in the bowls.

So, there are some conflicting things going on here....

 

[tritico]

Re: 93 fast strike 150 - fuel delivery issue (primer solenoid leak)

Is there a chance that warped carb bowls could contribute? I don't see any leaking fuel where the bowls attach to the carb...however, when taking them apart they seemed to be slightly warped! The gaskets look wet, but no visible fuel leaking so to speak. Does it sound like a vacuum/air leak issue to you? Thanks for the response.

 

[daselbee]

Re: 93 fast strike 150 - fuel delivery issue (primer solenoid leak)

No not really.

Engine off, you should pump the primer bulb up til firm, and it should hold that firmness.
This ensures that your carb bowls are full, and the fact that it is firm means that there are no fuel leaks (lines, needle/seats).
If it never gets firm, then you have a fuel leak somewhere.
Again, I am going on the fact that your primer solenoid DOES NOT leak unless the key is pressed.

Then, once started, the engine will usually run for 4-5 mins on that fuel in the bowls.

So, why does it only run 30 to 45 seconds....that is what I am wondering.

Warped bowls will leak if the float is too high...stuff like that. Bad running...etc. But they will not allow an engine to die out.

Any way you can tee into the fuel line running to the carbs, and either put a pressure gauge on it there or simply capture and watch the fuel flow. This would help verify the fuel pump operation? Pump should show 3 lbs or so, fluctuating.

I would think that it was loading up, getting richer and richer, until it finally dies. That is what you are describing.
BUT!!! You say you can keep it running by pumping the primer bulb. Does it run normally when doing the pumping? Normal idle?

 

[daselbee]

Re: 93 fast strike 150 - fuel delivery issue (primer solenoid leak)

Hey...Try this and post back:

Pump the primer bulb til firm, and then, using something to catch the gas, remove the drain plug in the bottom of one of the carbs. How much gas comes out? A bowl full, or a dribble?

If it is a dribble, there is no gas getting to the carbs from the priming action. The bowls may not be filling up. Maybe a fuel line routing mistake.

Look into that.

 

[tritico]

Re: 93 fast strike 150 - fuel delivery issue (primer solenoid leak)

Yes, runs normal when squeezing the primer bulb and keeping it tight. Have only run it at idle...on the muffs. And yes, the primer solenoid only leaks when pushing in the key. Thanks for the input...I will try your recommendation next week when I can get back to it. Will post back!

 

[tritico]

Re: 93 fast strike 150 - fuel delivery issue (primer solenoid leak)

found out last night that the fuel pump housing is cracked and leaking air....I assume for now that this may be my issue??

 

[daselbee]

Re: 93 fast strike 150 - fuel delivery issue (primer solenoid leak)

Now you have found something that will cause exactly what you describe. Fuel pump housing cracked will never allow the bowls to fill up due to the defective pump.

I bet your primer bulb never pumped up and got tight.....

That primer bulb is a very good diagnostic tool. If it will not get firm and tight, there is a leak somewhere.

When you get it all back together and fixed, take time and study exactly how that bulb feels, how it sounds when fuel is rushing thru, how many times you pump it before it gets firm, all so you can notice changes if they happen later.