Marlin priming switch

[jigstrike]

I have twin f250's, and after replacing the fuel water seperators, my starboard engine lost prime. I have a priming switch on the dash, and when I press it, I hear a pump, but it isnt getting me any fuel into the filters.
I am thinking of removing the priming pumps and installing priming bulbs instead.
Has anyone had experience with these electric priming pumps? I cant find anything on the internet about them.
Thanks!!!

 

[seasick]

If thi is an external electric lift pumps you may not need them but I am not sure that is your problem. You may have an air leak or pickup issue or a bad low pressure pump. In general, you should not need to pump the primer bulb of run the lift pump prior to starting except after changing filters, refilling VST tank or after longish periods of non use.

 

[DennisG01]

There still should have been fuel in your VST and the engine should have started.

Crack your filter open a bit and hold a rag over it while hitting the priming pump... do you get fuel there?

Is there fuel in your VST?

Yes, you could switch to bulbs if you want. As noted, it really "shouldn't" be necessary since, even with a dry filter, the engine's LP pumps should pull the fuel through (since, again, the engine will start since the VST is still full. "Should" being the key word... it certainly doesn't hurt to pre-fill the filters.

 

[jigstrike]

If thi is an external electric lift pumps you may not need them but I am not sure that is your problem. You may have an air leak or pickup issue or a bad low pressure pump. In general, you should not need to pump the primer bulb of run the lift pump prior to starting except after changing filters, refilling VST tank or after longish periods of non use.

Hmmm...
If it is a bad low pressure pump, would it just totally crap out? The problem started when I changed the filters on the engines, and added new Racor f/w separators. What is a VST tank?
Thanks!!!!

 

[DennisG01]

The silver tank on the port side of your engine. There's a high pressure pump in there and a filter. Drain it - collect the gas to check for quantity (and it never hurts to check quality, too).

 

[Fishtales]

Never heard of these on a GW, maybe an aftermarket add? I have bulbs and honestly I've used em at start of the year and don't touch them all all during the season.

 

[seasick]

Hmmm...
If it is a bad low pressure pump, would it just totally crap out? The problem started when I changed the filters on the engines, and added new Racor f/w separators. What is a VST tank?
Thanks!!!!

Ha, if the problem started after filter changes, I would bet that there is an air leak or that you inadvertently reversed the fuel lines. Vheck the hoses first and then remove and reseat all filters and make sure that old gaskets are not stuck to the flange.
When you have nothing to do take a look at this video on VST tank

I think it applies to your motor.

 

[wspitler]

My guess is that your motors are the older 3.3L F250s. If so, you engine has a much simpler VST than the 4.2L engines shown in the video. Still on the port side behind the intake manifold. but it only contains one filter. The LP filter is outside the tank between the LP pump and the tank.

 

[jigstrike]

Well... No luck yet, I am not getting power to the low pressure pump. I checked the fuses and they are good. I put a multimeter on the leads to the lp pump, and nothing! Are there any other fuses I am not seeing?
When I turn the key on, I hear a buzzing. It seems like it is coming from the vst.
Any ideas??
Thanks!!

 

[wspitler]

The HP pump is inside the VST. You need to get an electrical schematic ( ie. Maintenance manual) to see where the power to the LP pump comes from. You really should not need a priming pump.

 

[DennisG01]

What quantity of fuel was in the VST when you drained it?

We're still just kind of guessing on some of this - still need to know exactly what model you have.

You originally said the primer button turned on a pump... but now it doesn't?

 

[jigstrike]

Its the 6 cyl f250.
I bypassed the electric pump with a bulb. Getting gas to lp pump. Quality is good.
Gonna fill vst and run it. A yamaha dealer said to try that.
Hmmmm
Keep yall posted

 

[seasick]

Its the 6 cyl f250.
I bypassed the electric pump with a bulb. Getting gas to lp pump. Quality is good.
Gonna fill vst and run it. A yamaha dealer said to try that.
Hmmmm
Keep yall posted

If you are getting gas to the LP, you should also be filling the VST tank. After a while the primer bulb should get firm. It can take a lot of squeezes. If it doesn't get firm, there is another issue