Andair pump PIREPs?

digidocs · #1 01-04-2020, 03:53 PM

Any PIREPS good or bad on the Andair fuel pump that Van's is using in the RV-14? Thanks for sharing your experience.

Bavafa · #2 01-04-2020, 03:56 PM

I have nothing negative to say about the pump but I wish the fuel filter was easier to remove for cleaning. I have done it once so far for my last annual and the easiest was to remove pump/filter as one unit to be cleaned.

9GT · #3 01-04-2020, 09:09 PM

I had one in my RV-10. Worked great for the IO-540. Putting one in my -9A.

bmarvel · #4 01-05-2020, 11:04 AM

Interesting question as just recently I have run into something that has not occurred before in the 540 hours I have on my -14A.

I've worked through the usual hot start problems with a fuel injected engine but lately find I have to wait about 20 minutes after refueling before I can get the engine to start.

The problem is fuel related in that when I try to hot start, the engine does not fire at all on any cylinder. By experimenting and watching what is going on with the engine gauges, I note that I have zero fuel pressure even when the electric fuel pump is running and the mixture is in idle cutoff. Since my Dynon fuel pressure sensor is plumbed to the usual location on the outlet side of the engine driven pump, I should have fuel pressure there when the boost pump is on but it shows zero in this hot start situation. No pressure means no fuel flow and hence no start. Twenty or so minutes later I get pressure, flow and start.

With the Christmas holidays and helping another owner with his airplane, I have not had time to fully troubleshoot what is going on. But what it appears to be is some type of vapor lock on the inlet side of the electric fuel pump that prevents it from pressurizing the system. The pump is located in the tunnel per the plans and like I said has worked just fine for the past three years with both hot and cold starts.

So that's the mystery that I hope to solve soon.

SuperCubDriver · #5 01-05-2020, 11:26 AM

I have two Andair PX375-TC pumps in my RV-8. One failed after about 20 hours flight time, the other made strange noises and was repaired at the same time.
The same pump in my RV-7 (950 hours now after seven years) just failed last week after about an estimated run time of 20-30 hours with 2000 cycles.
The same pump in another RV-7 on a neighbor field just failed last year after about 20 hours flight time. I start to lose confidence in these pumps although I like it´s design.
Which pump is in the RV-12? I assume it is not the PX375-TC.

bmarvel · #6 01-05-2020, 12:13 PM

That is exactly what I do when the engine is cold except that I turn the pump on and monitor fuel flow, not pressure, to get 3 GPH and then pump off. With a cold engine that technique works great.

But in the situation I described with a hot engine after refueling, doing that same thing results in exactly zero fuel pressure and zero fuel flow unless I wait for about 20 minutes. I do not normally prime a hot engine after a short time on the ground but in this case I tried that just to find out what is going on. Everything points to the Andair trying to pump air, not fuel, from its inlet port, which it is not designed to do.

Again, this is new. I did not experience it in the past.

PilotjohnS · #7 01-05-2020, 12:24 PM

The only thing I can think of is one of the fittings near the pump is not tight or not fully sealing, letting enough air in to cause pump to Cavitate. You said it was fine before, so what was the last change?

bmarvel · #8 01-05-2020, 12:37 PM

Quote:

Originally Posted by PilotjohnS

The only thing I can think of is one of the fittings near the pump is not tight or not fully sealing, letting enough air in to cause pump to Cavitate. You said it was fine before, so what was the last change?

Nothing after the annual condition inspection and filter cleaning last year. There are no fuel leaks and no odor of fuel in the cockpit. And it has flown nearly 150 hours since. That's why I want to get in there and have a look at everything. I only brought this up due to the OP asking about Andair pumps. Will follow up when I complete a more through evaluation.

rv8ch · #9 01-05-2020, 01:04 PM

Quote:

Originally Posted by bmarvel

Nothing after the annual condition inspection and filter cleaning last year. There are no fuel leaks and no odor of fuel in the cockpit. And it has flown nearly 150 hours since. That's why I want to get in there and have a look at everything. I only brought this up due to the OP asking about Andair pumps. Will follow up when I complete a more through evaluation.

Agree it sounds like it's sucking air. Would be interesting to know what you find. I'm guessing a fitting has come slightly loose.

Aussieflyer · #10 01-05-2020, 03:36 PM

After about 18 months of operation I noticed that the electric fuel pump on my 14 was making a lot of noise. I contacted Andair and they suggested that I return the pump and they would overhaul it and change some parts over to update it to the latest model. Andair did this free of charge. No problems since. Obviously the early builds were supplied with an older model fuel pump that has now been enhanced and improved. It may pay to check with Andair to ensure you have the current and improved model if you were an early builder.