3-12-8 Fuel Pump Maybe??

[jeff lary 173]

I was mowing out back today after mowing the front lawn for about 2 hours absolutely no issues so far. Then I go out to where I planted some black berry plant's last spring. They are planted on a slop,e not too steep but I do slide over to the high side of the seat to keep traction in one spot. When I got to this steeper spot on the slope there were some branches that fell during the winter so I got off to move them. Then I found another 2 or 3 to move and looked briefly at an apple tree branch that had to be pruned. I left the tractor running all this time.

  When I get back on maybe 1 minute later put her in gear again and started to move along the slope. She immediately started to fade just like there was no more gas. I choked the heck out of it to get it to flatter ground. I took the fuel line off the top / outlet of the fuel pump and after a few seconds she started pumping fuel,.. kind of gurgling it out of the line not really squirting out of the line. The inlet line from the tank has a see through filter below the carb, and it was about 1/3 full of gas so I knew it was getting to the pump inlet side.

 After I could see it was pumping fuel out I put everything back together and after sitting there while I worked on it, it started right back up. So I mowed the remainder of the back garden lawn with zero issues" I mowed for about 1/2 hour longer".

Do you all think the pump is getting weak? it is an all original tractor 1995 except for spark plug and solenoid and battery. It acted up 2 times last summer when mowing deep grass it acted the same but came right out of it. I blew snow with this tractor every winter since new including last summer. I have to go back outside and work some more this is the first rain free day in over a week. I will check back in later today thanks. Jeff

[SPINJIM 1,981]

If the gas in you tank was low, the slope may have caused some air to be sucked into your fuel line.   I got a lot of air into my line one time, and had to re-prime the line and the filter to get the pump to pull the fuel up.

   Jim

[jeff lary 173]

Tank was 1/2 full slope was about 2:1.

I am going out now and look at the tank outlet to be sure fuel is flowing freely to the pump. If I need a new pump I would like one that is a direct replacement for the pump that came on the tractor. After all 22 years is pretty good service I think. Is there or I should say does anyone know what the replacement 3-12-8 pump part number would be and where to find one. Thanks a lot if any one has any input.

Edited May 12, 2017 by jeff lary

[WVHillbilly520H 10,376]

Don't forget the "partstree.com" tractor model and serial #s or Kohler engine model/serial #s should get you parts/ numbers you're looking for, another thing that could be an issue is the bronze screen/filter on the tank shut off bung could be getting clogged up after all those years especially if you have ever run ethanol fuel, Jeff.

[jeff lary 173]

Hi Hillbilly ,

Yes good catch there but alas no joy there either. I just took the petcock out and the very bottom of the screen had a very tiny amount of stuff on it. I sprayed some WD 40 backwards through the outlet to wash the screen from the inside. Then I hit it with lots of air and bing bang boom clean screen. I did forget about parts tree maybe I will try there. Next time I go to the shop I will look in the book or maybe on the engine for a model number. Then see if I can use that to find one at parts tree. I sometimes forget how to search different web sites so if that happens I may be back ! It wont be tonight and we are Mothers "daying "it tomorrow so maybe Sunday morning.

[jeff lary 173]

Well I lied ha ha ( I am nothing if not impatient) I just went to parts tree and found my tractor 95 3-12-8 went to fuel pump NA many other parts said the same thing too.

[953 nut 57,904]

I had a similar condition with my 312-8 a few years ago, figured it was running out of gas,pulled the gas cap and heard a momentary sucking sound. There was plenty of gas left, but the vent in the cap wasn't working so as the gas was pumped out a vacuum was being created that the fuel pump couldn't overcome. I bought a new fuel cap and haven't had any more problems.

[jeff lary 173]

Another good tip but my vent is fine checked it today. The cap /  measuring device Is new as of a couple years ago it was yellowed bad and I could not read it so I replaced it. As far as that goes the tractor runs fine too. But it did starve out today and 2-3 times last summer while in tall grass. I think it is the pump.

[doc724 925]

Likely the pump. They tired after 22 years.  Replacements are available everywhere.  Go to Jacks Small Engines and you want to look under "Kohler", not "Toro"

[chip61 664]

I've bought a couple pumps at NAPA. 

[jeff lary 173]

 

 

 

I went out to get some numbers off the tractor to look for a pump with From the engine, I found

ENGINE MODEL M12S

SPEC NO. 471627  THE "6" MIGHT NOT BE CORRECT ? I CANT SEE THE NUMBER VERY WELL

SEREIAL NO. 2709163093

 

FROM THE LEFT FRONT SIDE OF THE FENDER I FOUND THESE

MODEL 73363

SEREIAL 7900065 THE THIRD "0" I AM NOT SURE ABOUT AS THE STICKER IS TORN THERE

 

I went to Jacks small engines and typed in M12S and then fuel pump the price was $145.00 holy smoke !

 

I also saw this at e-bay will it fit? and what's up with all the fuel line inlet adapters? are they meant for different configurations  

 

 

http://www.ebay.com/itm/New-FUEL-PUMP-for-Kohler-Magnum-Series-M10-M12-M14-M16-10-12-14-16-hp-Engines-/270683506273

 

 

 

Edited May 13, 2017 by jeff lary

[chip61 664]

Yea that looks like the ones I got at NAPA. I'm thinking they all have plastic housings now? I don't remember how much I paid but it was less than $100.00. I was too impatient to order

online. 

It comes with different fittings for multiple line sizes and angles.

[jeff lary 173]

so did you just tell them the engine model or did you have to have the fuel pump part number? I am thinking e-bay to be honest but I was just curious.

[doc724 925]

All the fuel pumps for K series and Magnums I think are the same.  Yes they are all plastic and all those little adapters are for various line sizes.  You have to pick the one you want from the bag they enclose and install it in the right orientation.  Go to Amazon.  The last one I bought was $35 approx.  Kohler P/N for the K series engine fuel pump is 47-559-11-S, Magnum may be different.  One note of caution, do not press on the cam actuator on the pump with your hand, you can over extend the actuation and the diaphragm gets torn (I think).  I did this on the last one I bought and it would not pump at all (the old one I took off at least pumped a 12 inch stream).  Amazon did take it back though.

[Duramax7man7 506]

Just put This One on my 94' 314h as it wouldn't pump. Works great! Just like my 95' 312-8-s...

[953 nut 57,904]

You can pick up a low pressure electric fuel pump for about ten bucks on Ebay, free shipping! 

[jeff lary 173]

Thank you to all of you sometimes I think I have an idea what is wrong but I like to ask around a bit too. I do think it is the fuel pump and right now it is fine but it is old and will fail eventually. I am going to buy one and have it here on hand for when the inevitable happens.

 

Doc;

The one i have on there now does not even squirt fuel out of the line it just kind of "flows out". You say don't press on the cam actuator with my hand,.. as it may tear the diaphragm. I have never changed a fuel pump on anything before , I assume the "cam actuator" is the lever that sticks out the back?  When I remove / install the old / new one do I have to tilt the pump up or down to get it out of the engine? Does the cam lever go inside under / over something that I could get wrong when installing the new one? Thanks for any tips.

Mastiffman;

The  e-bay pump does not "look" like the one on my tractor now? the original pump is very flat compared to the one in the ad but you are saying it will fit? Jeff

Edited May 13, 2017 by jeff lary

[jeff lary 173]

953;

On the electric pumps,... you must have to wire in a separate power switch to power the pump right. So what if you get done mowing but forget to shut off the switch? Would you burn out the pump or flood the engine base ? Or did you wire it to the key switch somehow?

[953 nut 57,904]

9 minutes ago, jeff lary said:

Or did you wire it to the key switch somehow?

You should have a 15 amp fuse that is between the ignition switch and the light switch (dark green wire), just splice it in that wire and it will turn off with the switch and be protected by the same fuse.

Be sure to mount the pump low on the frame.

[doc724 925]

1 hour ago, jeff lary said:

Thank you to all of you sometimes I think I have an idea what is wrong but I like to ask around a bit too. I do think it is the fuel pump and right now it is fine but it is old and will fail eventually. I am going to buy one and have it here on hand for when the inevitable happens.

 

Doc;

The one i have on there now does not even squirt fuel out of the line it just kind of "flows out". You say don't press on the cam actuator with my hand,.. as it may tear the diaphragm. I have never changed a fuel pump on anything before , I assume the "cam actuator" is the lever that sticks out the back?  When I remove / install the old / new one do I have to tilt the pump up or down to get it out of the engine? Does the cam lever go inside under / over something that I could get wrong when installing the new one? Thanks for any tips.

Mastiffman;

The  e-bay pump does not "look" like the one on my tractor now? the original pump is very flat compared to the one in the ad but you are saying it will fit? Jeff

 

Jeff, the "cam actuator" is the arm that sticks out the back.  When you remove or install it, yes, you do have to tilt it to get it out.  The flat side of the cam actuator on the pump rides on a rotating part inside the engine so when you put it back in you have to keep the actuator close to the block (so the rotating part inside the engine hits the flat side.  BTW, the pump that Mastiffman cited is exactly the one I bought for my K241.  I had an old pump on a K301 engine I picked up last fall.  It is an original metal pump and yes, it does not look line the newer plastic ones.

 

WRT electric pumps, they are a great solution, but at the end of the day is will cost 2X the old mechanical pumps.  Between the pump, a fuse, and a relay and finding a place to mount it so that it does not get in the way of something, it is not a trivial task.  (electric pumps are pusher pumps just like in your car and they have to be located close to the gas tank).  I have toyed with the idea for my C141 which is hard to start if I leave it for a few weeks and do not keep the tank as least half full.  Since it only gets about 15 hrs of use a year, it is hard to justify all the work to install an electric pump

 

[WVHillbilly520H 10,376]

I have had very good luck with parts being correct (whether they looked the same) from theropshop/eBay, and on my F.I.L.'s CC 782 M17 the fuel pump didn't look the same housing wise but bolted on and works at it should plus the all the extra little fittings does come in handy, Jeff.

[jeff lary 173]

Ok so I went to the ropshop and put in the pn I had but nothing came up with the same number. So I went back up to mastiffmans link and went to it I was looking it over then said well they cant read your mind if you want it you have to buy it ! So I started typing in my address and at the top of the e-bay store post was the store's name ,.. see more at our e-bay store( The Rop Shop). I bought her up ! $36.00 shipping included. Once again thank you all so much I wish /  hope some day I can help you all with something as much as you have helped me. Now I an=m going to go back and read Doc's post a bunch of times!..Thanks Jeff

[jeff lary 173]

This is what I just bought

http://www.ebay.com/itm/FUEL-PUMP-Wheel-Horse-Tractors-Kohler-10-12-14-16-hp-K-Series-amp-Magnum-Engines-/271466673181

 

 

[Duramax7man7 506]

Yeah if you have a Kohler Magnum engine it will work. The Old one on my 94' 314h with  mag14 on it didn't want to work and when I took it part it looked functionally fine and fuel was getting to the pump. But with that rise to the carburetor they must just get to the point that they can't create enough pressure to lift the fuel that high. Even thought they still pump with low pressure. I'm sure the diaphragm just wears out like another other moving part, especially when exposed to the elements. Mine was sitting outside for a while before I brought it home. So it most likely deteriorated enough to fail.

I would just slap that new on and call it a day.

Edited May 14, 2017 by Mastiffman

[jeff lary 173]

yes I will put it in for sure.