Evo X upgrades - Page 93

**mlomker** · 05-25-2011

Fueling system died on the way to work and I barely got it into the office parking lot. The 044 in the trunk is making horrible death sounds. I'm going to have to do some parking-lot troubleshooting later today but it appears toast.

**Kracka** · 05-25-2011

Time to start using real brand name pumps rather than these modified/generic knock-offs?

**mlomker** · 05-25-2011

Quote:

Originally Posted by Kracka

Time to start using real brand name pumps rather than these modified/generic knock-offs?

I had a Bosch-brand 044 first and it didn't flow enough--it'd immediately overheat if you tried to BAP it. There's a reason that the Weldon was waiting to go in.

**scheides** · 05-25-2011

Ugh that is horrible news dude. That was the jay racing 044 right? Do they by chance make a submersible version?

**mlomker** · 05-25-2011

Quote:

Originally Posted by scheides

That was the jay racing 044 right? Do they by chance make a submersible version?

No, they have the PT342 which is what I'm running in the in-tank. It supposedly flows 340lph like the Aeromotive. I put my ear up to it and it's humming away in the tank. I'll verify flow from it before I swap my Bosch in tonight but it sounds happy.

**mlomker** · 05-25-2011

As is often the case, the problem was not AT ALL what I thought it was. It turns out that the Jay Racing PT342 is actually a rebadged Aeromotive 340. What's interesting about the Aeromotive? Reverse polarity! It don't pump so good when wired backward. It does make sounds like it is working, however. lol.

I drove all the way to work on the 1/2gal that was in my surge tank.

**goodhart** · 05-25-2011

Quote:

Originally Posted by mlomker

As is often the case, the problem was not AT ALL what I thought it was. It turns out that the Jay Racing PT342 is actually a rebadged Aeromotive 340. What's interesting about the Aeromotive? Reverse polarity! It don't pump so good when wired backward. It does make sounds like it is working, however. lol.

I drove all the way to work on the 1/2gal that was in my surge tank.

Ah WTF!

Gonna be doing some wiring tonight then? lol

**mlomker** · 05-25-2011

Quote:

Originally Posted by goodhart

Gonna be doing some wiring tonight then? lol

No real harm done since I didn't need a tow, so I'm laughing! lol.

I pulled the hanger and brought it home. I figure I'll go into work early tomorrow and drop the re-wired hanger back in the Evo. My boss was kind enough to give me a ride home to grab the beater.

**asshanson** · 05-25-2011

Quote:

Originally Posted by mlomker

I drove all the way to work on the 1/2gal that was in my surge tank.

Wouldn't most of the fuel from the surge tank just pass by the rail and go back into the primary tank via the return line? It seems like it would only take a minute for the external pump to go through the surge tank if the in tank pump wasn't doing anything to fill it.

Come to think of it, my 255 filled a gallon container in about a minute. Under throttle, most (if not all) of that is going to be used, but just cruising maybe 1/20th will be used, which means most of the gas just comes back through the return.

Is your surge tank 1/2 gallon? If so, it would only take about 30 seconds of your in-tank pump not flowing anything to run the surge tank dry, just because the external pump is always going to be flowing a lot, regardless if the motor uses it.

Or am I just high and not thinking clearly? Or maybe you have a return into the surge tank?

**mlomker** · 05-25-2011

Quote:

Originally Posted by asshanson

Or maybe you have a return into the surge tank?

Correct, the engine return goes to the surge tank. Overflow from the surge tank returns to the main tank.

**asshanson** · 05-25-2011

Oh nice, didn't even think of that until after I wrote the post.

**scheides** · 05-25-2011

Ok that is my big beef with the aeromotive pump, why on earth would they wire it backwards from the product they are directly trying to compete against? Makes ZERO sense!

Glad you figured it out, that is just nuts!

**mlomker** · 05-26-2011

The polarity fix got the pump working, of course. The problem is that it has too much flow for the return on the stock hanger and is pressuring the surge tank to ~6psi. This causes it to spring a leak at the 044 pump connection.

I think I've seen forum posts about ways to make the return less restrictive. Otherwise I'll need to downgrade that pump to a 255.

**goodhart** · 05-26-2011

Would it be easier to swap in a larger return line? like -6 or -8 or something? What size is it now? Then you could have the extra flow you may need down the road, AND have it not overflow. Either way, glad to hear ya got it working!

**mlomker** · 05-26-2011

Quote:

Originally Posted by goodhart

Would it be easier to swap in a larger return line? like -6 or -8 or something?

The line isn't the restriction, it is within the stock hanger. They have a restrictor that creates the venturi effect used to pull fuel over from the other saddle in the tank. It was designed with stock flow in mind. Some people drill it out a bit but it's a little risky because if you drill it out too far then it stops drawing from the other saddle and you run out of gas with the gauge reading 1/4 tank.

**Kracka** · 05-26-2011

Sell and replace with stock, 255, or DW300?

LMK if you need a stock pump.

**mlomker** · 05-26-2011

Quote:

Originally Posted by Kracka

Sell and replace with stock, 255, or DW300?

We will see. I have a pair of 255 in the Full Blown hanger so I could pull one to test with.

Discussion about increasing the return capacity:
http://www.evoxforums.com/forums/showthread.php?t=28036

**mlomker** · 05-26-2011

It looks like air in the fuel lines is my problem. I purged the surge tank/return and now that's all happy. I snugged up the surge tank fittings so no more leak.

Right now I'm getting no fuel pressure to the rail so I suppose there's air in that line as well. I ran out of lunch hour so I'll have to decide what to do with that later.

**asshanson** · 05-26-2011

Air in the feed line shouldn't matter, if your pump is running it should push those air bubbles out.

**mlomker** · 05-26-2011

Spend quite a few hours experimenting. It certainly appears that the return line for the stock in-tank hanger is too restrictive. I just swapped a regular 255 into the hanger and will give it a try in the morning. The car seems to run fine if I leave the in-tank pump unplugged but everything I tried with it running would result in fuel pressure going to 0 at the motor. I even swapped in the Bosch instead of the Jays 044 and the symptoms were identical.

I hope the 255 works. If not then I'll probably try cutting off the return hose in the hanger to bypass the restrictive return/siphon. Too many people eyeballing my car...leaving it parked in one spot for too long is making me nervous. I need to move that car tomorrow...even if that means running off the surge tank and stopping half-way home to refill it.