4.3 replacement motor. Having some fuel problems

[jbwrangler]

I double checked the baffles. They are in the same as your pic. (thanks for the pic) I am going to try removing the anti siphon (temporarily) to see if that helps. Something crazy with the fuel pump is all I can think of at this point. I have been avoiding that since it is $300 and the one I have seems to test out ok, but at this point I may just try it.

The only thing I have not tested on the FP is the input voltage. My assumption was it was ok since the pressure test checked out.

Thanks to all for your input. It really helps. I know we will figure this out.

 

[Mlevy]

You could go with a carter p4595 electric pump, that’s what I have on my boat with the 1409. Works great, only cost me 180cad at my local parts store, you could probably get it for less online.

mitch

 

[jbwrangler]

UPDATE...I think I have it solved. This morning I decided to to just start at the tank and work my way through the fuel system. When I started all this, the tank was almost empty. I put in 26 gal of new ethanol free gas in a 30 gal tank, so there was 4 gal of questionable gas in there. To be sure, I drained the tank. Next, I removed the pickup, but it would not come all of the way out. I didn't want to break anything,so I decided to just blow some air through it. When I did the tank ballooned out and stayed that way until I removed my air line. This told me that my vent was not working. I had blown out the vent earlier, so I knew the vent line was good. Turns out the vented gas cap was not venting. I had taken it apart and cleaned it earlier in the process, but it still was not working.

So, I think the fuel pump was creating a vacuum in the tank that either made the anti siphon too stiff for the FP to overcome, or the FP just couldnt produce enough pressure to overcome the vacuum.

I feel dumb that I tried so many other things and the dang gas cap was the problem. In my defense I did clean the thing and even tried running it with the cap on loosely, but even on really loose, it was still sealing off.

Thanks to everyone that commented.

 

[alldodge]

the tank ballooned out

Good to hear you found the issue

But you could have had an explosion there. Fuel tank max pressure in is about 3 psi.

 

[Mlevy]

Good to hear you got it working!