M Series Fuel Pump Life

[swervin]

I have the worst luck with fuel pumps. I have to replace my fuel pump almost every year. I had a 2005 M7 for five years and now own a 2007 M8 and both have had this same problem. I ran premix on the M7, but use the stock oil injection on the M8. I would blame alcohol in the gas except that this problem started for me years ago, before they even started adding ethanol to the gas in Utah. I never had this problem with my old 1998 Powder Special. Why would the M sleds be different??? No, it's not the screens or electrical; you can hook 12V right up to the pump and you can hear it trying to go but the shaft does not turn. You can switch polarity and try to spin it backwards or forwards, it makes no difference. In the sled or on the test bench, either way, the pump is frozen. I've never taken one apart, but it acts like corrosion on the bearings. I just bought a new one last February, and now it is bad 11 months later. In the past I've occasionally had them last even shorter times than that. Thank heaven for APEUSA.com or I'd be absolutely broke. Cat wants $450 for these stupid pumps, and APEUSA sells them for $115 (Walbro GSC 404). But it is still annoying to get up on the hill and try to start the engine and everyone has to go home because I've got no fuel pressure, then I have to order one and install it. Every year. Why does this not happen to everyone else? What am I doing wrong? Is there a way to extend the life of these pumps? Do you store your sleds full of gas or empty? Do you use a fuel conditioner before storage? One guy said take the pump out and fill it with mineral spirits in the summer. Seems a little ridiculous to me. I finally found a gas station that sells premium with no alcohol in it, but I'm not convinced that will make any difference... but I'll try anyway. Any other ideas?

 

[Anylizer]

Couple things... IMO it's not just the alcohol in the fuel that is causing problems, they have done a complete reformulation that is causing issues. Always store with a full tank, and dump the old fuel in your car before you even try to start it for the season.
Fuel conditioner/stabilizer is recommended, but it needs to be the "new" blue versions... the old "Red" stabilizers are useless with today's fuel.
The pumps are very sensitive to running dry. Specs say that if they run dry for more than 5/10 sec. pump damage can occur.
Additionally, the cheaper pump may not be of the same quality as the OEM pump. I have no info to support this, but it is a possibility!

A.

 

[swervin]

Thanks

Thanks for the tips. I didn't know about the blue stabilizers.

The oil companies sure don't make good gasoline, anymore, do they? This crap they make now goes bad in just a couple of months! I'm also wondering about water in the fuel causing corrosion in the pump. I do have a water absorber thing in the tank but don't know how effective it is.

FYI, I'm pretty sure the Walbro pump is the exact pump used in the OEM Arctic Cat pump assembly. The Cat pumps actually say Walbro on them. The difference in price is not due to quality, it is due to the extra parts in the Cat fuel pump assembly (the frame, pressure regulator, etc) plus Cat's markup.

 

[sunbather1969]

you are doing something

wrong, store full of fuel if you don't start every month in off time. I start every month and store with little fuel but I start every month always have always will carbed or injected nothing against fogging but I think a good idle every month is worth it all I do is put new plugs in at start of year . between me and my friends we've had 20+ m's never had a fuel pump problem and i'm the only one that starts monthly.

 

[Vern]

None of the m7s in our group have had this issue and there pushin 4k miles on the original pumps with pretty much no prep for summer storage nor starting on a regular bases. I would think either you have really crappy luck or your doin somethin wrong.

 

[swervin]

I agree, I just wish I knew what it is I'm doing wrong...

 

[sledtahoe]

agree

I have m7 with 8k plus on same fuel pump I do run lucas thru it often..

 

[Coldfinger]

Did you only experience one OEM pump failure before you went to aftermarket units?

 

[Vern]

Just throwing ideas out there, maybe there's an electrical problem like bad voltage regulator or something frying the pumps. But I guess there would probably be other issues if it were the reg. Not sure

 

[bcsnowdog]

05 m7 over 12000,00 kms 09 m8 8500 kms no fuel pump problems

 

[swervin]

OK so here's more details: Two different sleds, first one (05M7) had two complete stock Arctic Cat fuel pump assemblies replaced on warranty before extended warranty expired, then had two more fuel pumps aftermarket before I sold it (but remember, the aftermarket pumps I'm using are THE SAME pumps Cat uses.) Second sled (07M8) stock pump went out within a month of when I bought it last year, with 1200 miles on the sled. I replaced it with aftermarket, and now that one has gone out 11 months later. If it was electrical then why would two different sleds have the problem? I think fuel pumps are allergic to ME... LOL! Honestly, I have absolutely no idea why this is happening to me. I use quality name brand gasoline, I use a water absorber in the fuel tank, I never use old gasoline, I store the sleds full of gas then drain in the fall and put new in, I start the sled a couple of times each summer, and I have never run a pump dry.

When the pumps first start to go, they get weak and the sled won't start but I can unplug the pump and put a 9V battery on the leads and run it backwards then forwards and then plug it back in and then the engine will usually start. And once it's running it will keep running until I shut it off. But then if I let it sit more than a minute or so, then it won't turn again. (I know this because I have a fuel pressure gauge.) So then I have to repeat the process. This pattern lasts for 3-4 rides before the pump completely dies and even 12V won't turn the motor. So I may be wrong here, but it does not seem like an electrical problem to me. It seems mechanical, like maybe the bearings gradually wear out or get gunk in them or rust and freeze up.

 

[Anylizer]

While this may not be the solution to your problem, a couple things to note... Running the pump backwards is possibly damaging the impeller. In some cases the impeller is made of some form of rubber which gets stuck/glued to the pump housing... running the pump backwards causes the impeller blades to bend the wrong direction (like folding track paddles backwards) which can cause premature failure.
Also... WALBRO is a pump manufacturer... they make a lot of different pumps for various applications. Just because the pump "Fits" DOES NOT mean that it is built to the same specs as the Cat pump. (SPECS) refer to volume, pressure, voltage/amperage requirements, bearing size/surface, & load (continuous duty cycle)
If any of these specs differ from what Cat has requested from Walbro, the pump life will suffer.

 

[Daltech]

I use to take the pump out and force it from a battery, feeding it with pure 2 stroke oil when this happends. Usally let it pump a liter of oil. I always get pumps back to life with this trick.
And to all of you that nag about not using a oem pump. Cat has NEVER made their own fuel pump. These are walbros, and to find the a replacement from walbros, you simply read of the walbro partnumber on your stock pump, and order a new one of that number. No need to pay cat 4times just because theydont want to split parts.


Daltech

 

[mbcat]

I agree, I just wish I knew what it is I'm doing wrong...

Could it be your storage methods? Hot building etc speeding up the breakdown of the gasoline. Also have you ever cleaned your smartvalves in the tank. Take them out and soak in methyl hydrate. Both mycf7 and f6 have over 8000 miles with no pump probs!