Aeromotive Fuel Pump - Losing pressure
 

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?

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?

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

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.

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.

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?

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.

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

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?

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.

Aeromotives use the fuel to cool themselves so if they had to sat a long time and had to fight to draw fuel in you could have damaged them. Call Aeromotive...I always had good luck with dealing with them.

There great pumps if used often, when drag racing it seemed like every spring someone had one take a sh!t. Weldon would be your best replacement or put a primer pump teed to the inlet with a check valve

I hear ya, should have it all taken care of by then. Will also carry a spare, but I would save an awful lot of gas if you did tow me around....

Not a bad idea.

Turbo, they are slightly above the tanks, which I know is not the best, HOWEVER, they are mounted out in the open and very easy to get at. Otherwise, they would be mounted way down in the bilge which is probably not ideal, but I agree would help with the gravity assist.

Makes sense if I fried it starving it for fuel. Probably got clogged from what I saw in the separator, then running back to the marina may have taken out the pump or damaged it.

If you use a Weldon just use the rite size fuse. Sounds like fuel filter is plugged up happened to a friend with a 1075.

Your fuel water separator is burning the pump up. You need to put the separator after the pump. Also, it's best to mount the pump on the floor in the bildge. You shouldn't have anything but a 100 micron filter in front of the pump... Your pump is overheating and loosing its tolerances then you loose fuel pressure.

OK, I understand what you're saying.

What do you think about installing a small "lift" pump near the tank (as someone mentioned before). This would provide positive head, similar to mounting the pump on the bilge floor. Anywhere you mount the pump, it still has to "pull" the fuel out of the tank thru the pickup, so mounting the pump lower doesn't solve the issues 100%.

Call the pump manufacturer. They will give u all the do's and don't...

Buy a quality Weldon pump and don't look back.

When I was looking at electric pumps I was going to mount it on a metal plate with slack in the hoses so that I could lower it into the bilge but pull it up easily for testing and maintenance.

Yup - I've had two go bad over the last five years. They run but just won't hold the required pressure.

I found Aeromotive fuel pumps to be grade A dogshet when I used them in drag racing. Find a better pump, otherwise you will be in for a long road of dissapointment.

Stay away from a gear rotor design they are s-ity Go with a vane type pump. Vane pump will prime better.

Anyone have a PN for the direct Weldon replacement to a Aero A1000?

How much power are you making? Weldon has a few in line pumps available.

1000-1300, mostly set around 1075-1100hp

PN-1100-A ???

http://www.weldonracing.com/#!store/...egory=14825055

Are Weldons Vane pump style?

Magna Fuel pumps are pretty good also

[QUOTE=frickstyle;4445348]1000

The 1075/1200 mercruiser uses a 2025 pump. Call Weldon they will give you the rite answer.


http://www.weldonracing.com/#!faqs/q2b62