Air leak in fuel pump? Evinrude '94 E150EXERV

[woodycooper]

Currently motor runs fine at idle and runs fine on a plane for about 20 seconds then she just loses power as if there is not enough fuel. Removed the water pump (newly rebuilt) and found a broken diaphram, so I put the old one (not torn) back in. Still same problem, so I installed a clear hose from the outlet on the vapor separator and into the fuel rail for the carbuerators. Also put a clear hose from the port side fuel inlet (after the external filter and tank) to the fuel screen in the engine. Hose ran clear from the tank/filter but I got bubbles after the vapor separator (see attached video). I'm assuming I have a leak in the fuel pump, vapor separator, or attaching hoses somewhere. Any words of wisdom? Is my assumption correct?

 

[racerone]

Water pump or fuel pump ?

 

[woodycooper]

Water pump or fuel pump ?

Uhh yeah... Sorry just replaced that too and have it on the brain.

 

[Chris1956]

That motor has a fuel pump and a vapor pump. I would check/rebuild the vapor pump. It is located on top of the vapor separator.

Also, check the main gasoline strainer. It should have an oring and gasket to seal it. She will suck air from there if those are not working.

 

[woodycooper]

That motor has a fuel pump and a vapor pump. I would check/rebuild the vapor pump. It is located on top of the vapor separator.

Also, check the main gasoline strainer. It should have an oring and gasket to seal it. She will suck air from there if those are not working.

Thanks. I'm putting in a new fuel pump this afternoon. I know conceptually what and where the vapor separator is, but what is the vapor pump? The VS just vents fuel vapor back into the intake from what I understand, and has a float in it? I guess that will come apart if the new fuel pump doesn't eliminate the bubbles. Already checked the screen and replaced the gasket. I've replaced this before as you can only remove and re-tighten the screen a few times before the gasket tears up.

 

[racerone]

There is a little square vapor pump. ----Seen right above the thingy with the red lever. -----That little pump came out in 1967 on small motors as a fuel pump. ----It was adapted to get rid of vapor on those motors. ---Repair kit is available.

 

[woodycooper]

There is a little square vapor pump. ----Seen right above the thingy with the red lever. -----That little pump came out in 1967 on small motors as a fuel pump. ----It was adapted to get rid of vapor on those motors. ---Repair kit is available.

Installed new fuel pump, now she runs fine. Here's the lesson: even though rebuild kits are available, just buy the new pump. The rebuilt one failed pretty much right away. Either I did it wrong or it wasn't designed to be rebuilt. I have a few bubbles going by at idle still but once you go obove 1000RPM it flows clear. When I get a chance I'll remove the vapor separator and see what gives.

 

[Crosbyman]

typical VST .. not yours but similar role

 

[racerone]

In my opinion the VRO pumps are very simple.----Easy to inspect / repair.-----I would never buy a new fuel pump !

 

[woodycooper]

In my opinion the VRO pumps are very simple.----Easy to inspect / repair.-----I would never buy a new fuel pump !

I did inspect it, found nothing wrong but put in new diaphrams anyway. During the first few hours one of them tore. Put the original back in, same thing. Rather than take it apart again and take my chances I just bought a new one. I took it apart just now and it looked perfectly fine. Now the new one sets off the VRO alarm out of the box but that's a problem for another day. I also am on my third set of thermostats and all of them so far do not open on time either. The last set is OEM, better but not correct according to the book. I've never seen so many bad parts right out of the box.

 

[saltchuckmatt]

I did inspect it, found nothing wrong but put in new diaphrams anyway. During the first few hours one of them tore. Put the original back in, same thing. Rather than take it apart again and take my chances I just bought a new one. I took it apart just now and it looked perfectly fine. Now the new one sets off the VRO alarm out of the box but that's a problem for another day. I also am on my third set of thermostats and all of them so far do not open on time either. The last set is OEM, better but not correct according to the book. I've never seen so many bad parts right out of the box.

I take it you pumped and bled out the oil correctly when you installed the vro?