fuel problems - any ideas

[cluxford]

On Fri I was out n about and the fuel pump died....tilt trayed home

Couldn't work on it till today....I'm in Australia so it's now Wed

OK, so started this morning with sparky.

Blown fuse, pop in a new one, fires up perfectly, then 1 min later...dead...no fuel pump. Fuse gone...replace, but wire across the fuse to circumvent it blowing

Drawing right amps...pump still not working

Pump primes for split second then starts "clicking"

We suspect it's the pump. So I call Aeromotive. They suspect pump screwed. I call VPW they have one, so I order it and have it delivered today. Aeromotive say they will fix and replace if I pay shipping.

So new pump arrives 2pm.

I get under rip out the old one (not easy, have to pull battery and few other things). Pull the pre pump filter, clean it, had some crap in it but very very small metal "specs" but not a lot.

Draining the full tank was the longest part.

Put it all back together with the new pump, put the fuel back in...

Fire it up.

Starts, runs 1 min...fuel pump stops again (this time brand new pump).

Now pump will prime for like 1 sec then "lock up" - doesn't click like the old one, but you can hear it ain't turning, it's trying but can't

so next step is we pull the inlet off the regulator so see if fuel getting to the reg...yep for the 1 sec it primes it pumps fuel to the reg inlet, as soon as it "locks up" no more fuel

So get the sparky back, we "hot wire" the pump to 12v jump pack. just locks straight up...no priming. We pull the old one out of the box, connect it to the jump pack, spins like crazy and works perfectly...this was the pump that was "clicking".

So now what is going on ?

Here is the system:

-10 out of tank
into 100 micron filter
into pump (all -10 lines) (Aeromotive A1000)
out of pump into 70 micron filter
into reg
reg splits to carb and a return line (-10) to tank
Tank is vented

Tank was full when this happened (filled up 5 mins earlier)

Tomorrow I plan to pull the outlet out of the pump that goes to the second filter and see if I disconnect it from the second filter it pumps into a bucket.

Struggling....not sure what's going on. It ain't electrical and there appears to be no blockage (given it pumps fuel when the pump spins), no vapour lock...just weird

68 Camaro
632 BBC (World Crate Merlin III)
Dominator 1050 Carby

Any ideas anyone ?

[camcojb]

what does your 100 micron pre-filter look like? Debris, plugged?

[cluxford]

nah pretty clean, had some "specs" in it, but I flow tested it and flow was fine, pump was also full of fuel so I know the fuel is getting through there

But I am thinking along same lines there must be some form of blockage that results in the pump locking up

[66GTFB]

Hey cluxford,

I doubt this will help your problem, but are you running an electronic fuel pump controller with your A1000 pump?

The pump (A1000) on my mustang suddenly stopped working and we pulled it apart and it was all burnt out. I read up on Aeromotive pumps and they recommend that if you are driving for more than 30 minutes at a time, to run the fuel pump controller, so it isn't running flat out all the time. Mine wouldn't have had 2000k's on it.

http://www.summitracing.com/parts/AEI-16306/ or at VPW http://www.vpw.com.au/productgroup.asp?CatID=6&SubCatID=777&priorCatID=777&PrdGrpID=2326

Just thought I'd give you a heads up, incase your pump burns out in the future.

Cheers,
Joe.

[BanditDave]

My recommendation is to isolate the problem....since you have the new pump back, get a clean bucket of gas jug and run the pump, no filters, to see if you can continuously run the pump for an extended period of time. Then add the filters in the same test - one at a time.

Then hook it back up the car and run it with an external power source to verify it is not the vent ofr return to the tank. If you can get it to run like that then hook the existing wiring up to see if it will continue...etc...

Take it step by step until you hiccup again....

Good luck!

[cluxford]

Hey cluxford,

I doubt this will help your problem, but are you running an electronic fuel pump controller with your A1000 pump?

The pump (A1000) on my mustang suddenly stopped working and we pulled it apart and it was all burnt out. I read up on Aeromotive pumps and they recommend that if you are driving for more than 30 minutes at a time, to run the fuel pump controller, so it isn't running flat out all the time. Mine wouldn't have had 2000k's on it.

http://www.summitracing.com/parts/AEI-16306/ or at VPW http://www.vpw.com.au/productgroup.asp?CatID=6&SubCatID=777&priorCatID=777&PrdGrpID=2326

Interesting...yeah mine runs flat out and yeah I do run over 30 min trips. It died though 5 mins into a trip...but runs great in external power so I know the pump ain't burnt out but will definitely look into a controller

Just thought I'd give you a heads up, incase your pump burns out in the future.

Cheers,
Joe.

My recommendation is to isolate the problem....since you have the new pump back, get a clean bucket of gas jug and run the pump, no filters, to see if you can continuously run the pump for an extended period of time. Then add the filters in the same test - one at a time.

Then hook it back up the car and run it with an external power source to verify it is not the vent ofr return to the tank. If you can get it to run like that then hook the existing wiring up to see if it will continue...etc...

Take it step by step until you hiccup again....

Good luck!

Thanks, that is the plan today...step by step, take each piece out of the equation

[Vegas69]

Sounds like a wiring problem. Check your ground.

[cluxford]

Sounds like a wiring problem. Check your ground.

Yep, been down that path, that was one of our first thoughts. We hotwired the pump directly to a battery. Works perfect when not in "the system" but connect it up to the rest of the fuel system and it locks up (even hotwired with a direct power source)

[Vegas69]

Did you use the cars ground for the test?

Maybe something is stuck in the pickup inside the tank.

How is the tank vented?

[cluxford]

Did you use the cars ground for the test?

Maybe something is stuck in the pickup inside the tank.

How is the tank vented?

No not the cars ground...good point, will check that today

It's vented in two places. Has a RideTech vented cap and also a breather at the top of the tank, I even tried it with the cap off as I thought it may have been a vapour lock or something like that

It's a weird one, I know that much

[Vegas69]

I'm assuming you are running a relay?

[cluxford]

PROBLEM SOLVED - The post pump filter was blocked, but here is the stupid thing.

I bought the whole thing as a kit from Aeromotive. The post pump filter is supposed to be 70 micron. It's not. It's a 10 micron.

It's clean, no specs or shavings, super clean, but I think being almost solid cardboard fins it's just got to the point that no petrol could get through. It blows through on first prime then blocks and dead heads the pump.

Anyway can't get one locally today so car is running with only pre-pump filter to get her home (7 K's).

New either 60 micron or 100 micron (probably go 100) filter will be ordered today from the states....

[Vegas69]

I've been running an 8 micron post pump since day one. Works fine... 5200 miles.... It is a steel mesh though.

I don't remember if you have a carb or injection. Not sure it matters. 100 micron isn't sufficient for injectors or a needle and seat. I still think you may have another problem.

[cluxford]

I've been running an 8 micron post pump since day one. Works fine... 5200 miles.... It is a steel mesh though.

I don't remember if you have a carb or injection. Not sure it matters. 100 micron isn't sufficient for injectors or a needle and seat. I still think you may have another problem.

It's a paper element, I'm going to a stainless mesh one. They have a high flow 40 micron one

It was definitely the filter. We poured fuel in it and could hardly get a trickle out of it either gravity or under pressure.

I have subsequently done some research and there is a 2009 bulletin on the Aeromotive web site that actually says you should keep a spare 10 micron paper element spare as they have a tendency to "clog up" with new fuels and their alcohol content. I've been running 98 octane since day 1.

regardless i think they should last longer than 600 K's but sure I have nailed the problem...

Thanks for your thoughts, they did get me thinking which is the support I was after

[Vegas69]

That's crazy, glad you found the problem.

[66GTFB]

Glad you got it sorted. Hope to see the feature of your car in Street Machine mag soon.