frickstyle

I have an issue with losing fuel pressure in port engine.

Anyone have problems with Aeromotive electric fuel pumps?

I can get it to push to 7lbs when siting at idle, and also in gear. It was holding pressure, and then when I get up on plane, it will bleed down to Zero in a few seconds. So I bring rpm down on engine, and it creeps back up. Try again to get on plane and it will drop down to zero.

Yesterday, cleaned the fuel/water separator and the inline filters. They did have a lot of gunk in them, put everything back together primed it, and it fired right up. Also, blew into the pickup tube to make sure it wasn't clogged at pickup, seems fine, no resistance (no blockage).

Pressure looked good, but when we went out after getting on plane to 30 seconds, pressure drops again.

I figured these pumps are either "ON" or "OFF:, meaning they are either good or bad, no in-between operation. All electrical connections seemed fine. Any ideas?

turbofox54

Had a similar problem on a bmw I was working on...sounds like a restriction in the line. But first verify voltage at the pump and then to eliminate the pump I would swap them side to side to see if the problem moves to starboard engine. If it does its the pump...if not make up a pressure guage on a t fitting that you can put in line at each junction to narrow down the restriction.
Where are your filters in relation to the pump?

Unlimited jd

iTrader: (5)

Sounds like it keeps sucking crap into the filters. We're the tanks cleaned out during your multi year multi million dollar rebuild?

turbofox54

That's why I asked where the filters were in the system. I have run aeromotives on a few cars and always have put a 100 micron on the inlet and 10 micron on the outlet. And always set the pump below the tank so it is gravity fed vs having to draw fuel in.

Yamaha24

I was wondering when this topic would come up.

Well, I have had nothing but problems with Aeromotive fuel pumps. Last year we had 3 go bad, yes 3. Sooo I sent all 3 into Aero and they sent me brand new ones fresh out of the box no questions asked. I thought that was pretty good of them, so I get the 3 brand new ones I hook two up to my brand new Chief engines use the boat for a good 8 hours in Florida to test new engines, I wash boat, winterize, get cabin interior done and store boat up until last week I back into the water one engine starts one does not, mind you boat ran perfect in Florida.
I am sitting there scratching my head as to why the boat won't start, so I decide to hook up a mechanical pressure gauge to it and wouldn't you know it 12PSI.(I do not have my dash pressure gauges hooked up yet) So I grab another new pump hook it up bam boat fires right up.

I pulled off the black marine ones and switched to a better Aero pump the chrome ones for now, those have worked fine so far. In LOTO I had one go out so my mechanic/friend who was with me looped both engines together so we could plane off.

We are going to be calling Aero this week and figure out what is going on.

I have zero restrictions in my lines and I am running two fuel filters.

frickstyle

Here's the plumbing (could not find a picture):
Pickup in tank > fuel / water separator > 100 micron in-line filter > pump > 10 micron in-line filter > carb dist block > pressure regulator > return to tank

Sooooo, the pump has to suck a lot and have a good head of fuel. Took a few tries to prime both the separator and the filter / pump portion of the circuit. I think I may have fried the pump running it low on fuel. But it goes up and then down and back up to pressure. Is this possible? Or maybe the pump was damaged with all the sediment flowing through it?

SB

iTrader: (1)

With a return line, should be simple to do a volume test. Engine off, put return into a fuel jug. GPM x 60 = GPH

or more exacting, you can do it by weight.

snapmorgan

iTrader: (2)

Swap them out for some Weldon's and be done with it. I don't want to have to tow you all over Old Hickory when you come down

frickstyle

Definitely was crap in the tanks. After the final hoora, we pulled the boat and I left, I was done messing with it.

Going to go install a new pump this week, check/replace all filters, stick a bore-scope down the pickup tube, aaaaand, then maybe go boating.


Has anyone burned up one of these pumps? If so, what was the cause, and how did it act? Did it just stop working, or was it functioning partially?

turbofox54

Seems like a lot of inlet restriction...where are the pumps mounted vertically in relation to the fuel tanks and fuel level? I ALWAYS made sure I had my fuel level higher than the pump.