New fuel pump recommendation

[HalcyonS]

Hi all
I've not been around for a year. I want to report on my fuel line problems which regulars might remember I posted several times about:

http://www.moyermarine.com/forums/showthread.php?p=103396

I also see a couple of threads about facet pumps.

I had my carb off for clean-out 3 times in 3 years and fuel supply problems persisted. Was in crud in the old Monel tank? - possibly. But I've now got 3 filters in-line - an old school bronze WC water separator, a 50 micron canister and a 10 micron polishing filter - that crud is NOT getting thru.
I'd previously added an oil pressure switch bypass to a momentary switch. I then added a pressure gauge - not damped so it rattles around, but I can now bring fuel up to pressure before turning the engine over. But I still had problems. Every time I took friends sailing, I prayed the thing would start, and as often as not, it failed. Most embarrassing.

I pulled off the facet and installed an airtex E8251, 2.5-4psi pump for half the price - $28. After 10 years of fuel supply problems, my old A4 starts right up every time. What a relief. I'm done with facet and recommend the airtex. YMMV, of course.

[ndutton]

Was the Facet pump a recent replacement or had it been subjected to the contaminated fuel?

[edwardc]

... I can now bring fuel up to pressure before turning the engine over. But I still had problems. Every time I took friends sailing, I prayed the thing would start, and as often as not, it failed. Most embarrassing.

I pulled off the facet and installed an airtex E8251, 2.5-4psi pump for half the price - $28. After 10 years of fuel supply problems, my old A4 starts right up every time. ...

Something's not making sense here. A bad fuel pump shouldn't keep it from starting. Even with the fuel line disconnected, the A4 should start and run for 30 seconds or more on just the fuel in the float bowl.

Did you touch ANYTHING else when you swapped the fuel pumps?

[roadnsky]

Something's not making sense here. A bad fuel pump shouldn't keep it from starting. Even with the fuel line disconnected, the A4 should start and run for 30 seconds or more on just the fuel in the float bowl.

Agreed. Mine will run 1-2 minutes after I shut off the fuel pump.
Also would like to hear an answer to Neil's question...

[JOHN COOKSON]

My first impression, because of the intermittent nature, is this is (was) a electrical problem.
Letting my mind wander ........
If the electronic fuel pump was a wired to coil +, in the conventional manner, and there was no electricity at coil + the pump would not operate and the engine would not start.
You could shake the boat's ignition wiring around while the engine is running and try tapping on the key also just to confirm that there is no loose connections in the wiring and the key (or switch) is good.
When trouble shooting an electrical device it is important to trouble shoot the device itself and the associated electrical circuit.

TRUE GRIT

[roadnsky]

Hi all
I've not been around for a year. I want to report on my fuel line problems which regulars might remember I posted several times about:

http://www.moyermarine.com/forums/showthread.php?p=103396

Simon-
I went back and re-read the thread you linked to.
In the thread, after installing the new pump, it seems you still had off and on issues right up until your last post last December.

12-7-2016
took the afternoon off to clean the carb.
Ran like a clock for almost an hour. Then I went home.

Has the engine been running well since that last post?

[HalcyonS]

Hi all
thank you for your thoughtful replies.
sorry to delay replying, lots going on.
To respond to all comments:

My system has a shutoff valve at the tank and I am the habit of running the carb, line and filters 'dry' when I leave the boat. So there is no fuel if the pump does not work. This is why I added the momentary fuel priming switch across the oil pressure switch.

I did in fact mess with much of the fuel line, moving pump to sidewall of engine compartment, adding fuel pressure gauge and moving the polishing filter to between pump and carb.

The facet pump (perhaps the 3rd I'd fitted in the last 6 years) was never exposed to 'contaminated fuel' in the sense that the filters between it and the tank successfully pulled out crud from tank. However, filters cannot remove things which are truly in solution.

I had observed what I called 'carburetor cheese' in the carb when I opened it up (i.e. around idle jet, and surmised this was some kind of precipitation related to the changed of temp in the carb due to evaporative cooling, and its effect on unknown fuel additives in gasoline in Southern California (Neil has spoken about unknown additives I the unleaded fuel here). I also noted stuck ball valve in the facet (twice), and decay of the rubber sealing gasket in the bottom of the facet, consistent with the effects of odd solvents.

Jerry said "In the thread, after installing the new pump, it seems you still had off and on issues right up until your last post last December".

In which case I am an unreliable witness. I apologize for not recalling correctly.

I used to dread trying the start the engine every time I went to the boat, and depressingly regularly, my dread was well founded, the engine did not start. I believe it was not an electrical issue. Abandoning facet does seem to have fixed my problem. My considered opinion is that the facet pump is not reliable with socal gas in normal boat-type use. I suspect that something precipitates out of the fuel in temp an pressure changes, and gums up ball valves and jets. But if I am the only social A4 owner who has these problems then maybe the old Monel tank somehow plays a part. I don't know, with unknown additives and complex chemistry I doubt we will find out.

I am greatly relieved that since installing the airtex, it start right up every time without hesitation. (I hope it continues to do so ) And it is upstream of the polishing filter, whereas the facet was aways downstream of it.

I wish you all fair winds and a minimum of engine trouble
S.

[ndutton]

Simon, that was a thorough, well reasoned analysis of your engine difficulties with what appears to be a successful outcome.

However . . . . .

We share some similarities but with completely different experiences over the past 12 years. For example:

• We are both in Southern California with the same fuel blend. I get mine from a local high volume gas station (typically ARCO) as opposed to a fuel dock and transport it to the boat in a 5 gallon jug. I have had zero contamination.
• We both have/had Facet cylindrical electric fuel pumps. You've gone through three while I'm on the same pump I replaced 12 years ago. There was no indication of a problem with the original Facet pump that came with the boat, I changed it because I did not know its history.

Now the differences:

• I have no polishing filter. Maybe I'm whistling past the graveyard but I've never needed one.
• Not sure what type you have but my primary filter is a cheap cartridge type spin on that I replace annually.
• I never run my fuel system dry. I was advised against the practice over 20 years ago by a highly regarded Yamaha outboard mechanic and have heeded his advice since.
• I don't know what if anything you use but as for fuel additives I use MMO @ 1% and nothing else.

[Marty Levenson]

running dry...?

Neil - I'd be curious to hear the logic of not running the carb dry...?

Thanks!

[joe_db]

Neil - I'd be curious to hear the logic of not running the carb dry...?

Thanks!

I run my carb dry both on my A4 and both outboard boats and it seems to do a lot of good. The outboards DEFINITELY get gummed up if this is not done and this has been SOP for outboards since I was a little kid.

[ndutton]

The mechanic's comments made perfect sense to me. He said the engine will starve and shut down before all the fuel is run out of the carburetor leaving the rest to evaporate to residue that much quicker (due to residual fuel volume/air volume proportion in the carb bowl), exactly what you're trying to prevent in the first place. He did not suggest this was unique to 2 stroke engines with mixed fuel but even if it was my 1% MMO mix would be the same. Like I said, I've never run the fuel out and some of my layoffs have been long. Zero problems.

I have no idea what long term effect running out the fuel would have on a fuel pump but wanted to point out it's a different practice on Simon's boat than on mine. He's had fuel pump problems while I have not so I wanted to note all differences between the two.

[HalcyonS]

Hi Neil
thanks for your note. My only clarification - when I said additives, I meant what the gas companies put into unleaded. I only add MMO. And we both buy from Arco

.[*]I don't know what if anything you use but as for fuel additives I use MMO @ 1% and nothing else.[/LIST]

[HalcyonS]

running fuel line dry

Thanks Neil
I always appreciate your thoughtful notes.

I run the full line dry for safety reasons. I don't have an opinion about running the carb dry in terms of gumming up. But thinking about it, it seems that if gas will evaporate incrementally from a full or half full bowl, there is less of everything in a half full bowl.

In any case, my problem was not 'gum' but some other kind of precipitate that, as noted, looked and felt like finely grated parmesan cheese, until it dried, when it became a white powder. Its possible that the powder was finer than 10 microns, and for some reason precipitated out at points of high velocity movement and vaporisation at jets. Dunno. I'm an armchair chemical engineer at best.

Simon

The mechanic's comments made perfect sense to me. He said the engine will starve and shut down before all the fuel is run out of the carburetor leaving the rest to evaporate to residue that much quicker (due to residual fuel volume/air volume proportion in the carb bowl), exactly what you're trying to prevent in the first place. He did not suggest this was unique to 2 stroke engines with mixed fuel but even if it was my 1% MMO mix would be the same. Like I said, I've never run the fuel out and some of my layoffs have been long. Zero problems.

I have no idea what long term effect running out the fuel would have on a fuel pump but wanted to point out it's a different practice on Simon's boat than on mine. He's had fuel pump problems while I have not so I wanted to note all differences between the two.

[ndutton]

What enhanced safety are you getting by running out the fuel? It seems to me the fuel lines should be able to contain the fuel indefinitely and if they are suspect they should be replaced. The carburetor float valve is a potential failure point (voice of experience) and to that end I have a manual shut off valve immediately ahead of the carburetor per USCG requirements. That valve remains closed unless I'm underway.

It is baffling to me that one boat has carburetor cheese (you're not the first) and another with a seemingly identical installation in the same climate and environment does not. When that happens - like now - I start looking for differences, even subtle ones. It's interesting that the boat with the cheese also had (past tense I hope) pump problems. I'm sorry it's you, glad it's not me.

Unrelated side note:
Hooray! MMI 502 flange pump arrived today.

[joe_db]

What enhanced safety are you getting by running out the fuel? It seems to me the fuel lines should be able to contain the fuel indefinitely and if they are suspect they should be replaced. The carburetor float valve is a potential failure point (voice of experience) and to that end I have a manual shut off valve immediately ahead of the carburetor per USCG requirements. That valve remains closed unless I'm underway.

It is baffling to me that one boat has carburetor cheese (you're not the first) and another with a seemingly identical installation in the same climate and environment does not. When that happens - like now - I start looking for differences, even subtle ones. It's interesting that the boat with the cheese also had (past tense I hope) pump problems. I'm sorry it's you, glad it's not me.

Unrelated side note:
Hooray! MMI 502 flange pump arrived today.

1. If I run the gas out, I am a long way from having gas leak out of the carb because it would first have to siphon enough to refill the carb, which on my boat it never does.

2. This seems to be a function of ethanol corroding aluminum. When I got a new carb, this issue went away (for now). I think there is a coating that eventually wears off and makes the carb far more prone to it. SeaFoam is cheap and has good anti-corrosive properties, so I use that with every tank.