kto434 108 #1 Posted June 3, 2018 (edited) Hi all. Turns out the fuel pump on my Kohler-powered 312-8 needs replaced. The part number is 4739320. Any suggestions rebuilding the original vs. buying a new one (if a new one, what brand?). Prefer a quality replacement over cheapest possible offering. Checking internet a genuine Kohler replacement is almost $200 (which, too me, is unreasonably steep). Thanks. Edited June 4, 2018 by kto434 Share this post Link to post Share on other sites
peter lena 8,639 #2 Posted June 3, 2018 recently replaced my fuel pump on 312-8 , picked up the latest plastic model on e bay, 16 $ , started right up, new in line filter, idles well and responds instantly to any carb adjustments. already have about 5 hrs. on it , no issues, glad I did it , pete 2 Share this post Link to post Share on other sites
Exhaust 25 #3 Posted June 4, 2018 Here is a link to the same part on Amazon for about $35, https://www.amazon.com/4755904-S-4739319-S-4739320-4755911-S-1T4G3484TYG420528/dp/B01MAV76YD I can't comment on rebuilding a fuel pump but at that price I would tend to spend the money on a new one instead of tinkering with the old. I'm in a similar situation myself but a carburetor is the issue. It's about $90 for a new one. I'm not set on buying it yet though, other issues may be playing a part in the poor running of the engine. Fuel cap, fuel filter, might need a fuel pump, and have to open the carb up to see what condition it's in. Share this post Link to post Share on other sites
kto434 108 #4 Posted June 4, 2018 (edited) thanks guys. as far as i know the fuel pump i am replacing is original to the tractor. i like my equipment oem when reasonably possible. the $200 kohler wants for a replacement fuel pump (to me) is not reasonable. i just don’t want a cheapo replacement that will leak/fail quickly. the difference in cost between kohler and most other replacements is so big i wondered if the $25 to $35 items were essentially imported junk. guess i will try one and find out. i appreciate your input/comments. Edited June 4, 2018 by kto434 Share this post Link to post Share on other sites
Maxwell-8 4,277 #5 Posted November 20, 2021 Mine is leaking, I would prefer rebuilding it. I need just a new gasket What is the part number for it? Can't find it on the m12 partstlist Share this post Link to post Share on other sites
Maxwell-8 4,277 #7 Posted November 20, 2021 11 minutes ago, pfrederi said: Thanks but that is the gasket were the pump mounts to the engine. I explained it wrong, I am sorry. I meant the membrane. Share this post Link to post Share on other sites
pfrederi 17,741 #8 Posted November 21, 2021 Then and now sells membranes and other parts. https://www.then-now-auto.com/fuel-pumps/ However for about the same money i just go Electric Facet Posiflo 2 1 Share this post Link to post Share on other sites
953 nut 55,325 #9 Posted November 21, 2021 Your Kohler "M" probably has a plastic body and "Then and Now" kits say the valves don't fit well on them. You can buy the diaphragm alone but in the long run you are best off going with a good quality electric fuel pump. 1 1 Share this post Link to post Share on other sites
Bill D 1,926 #10 Posted November 21, 2021 I've gone this route. Homemade mounting plate, OEM Kawasaki pump. The pump is available online for $30. Works great. Share this post Link to post Share on other sites
gris71 12 #11 Posted January 8, 2023 On 11/21/2021 at 11:33 AM, Bill D said: I've gone this route. Homemade mounting plate, OEM Kawasaki pump. The pump is available online for $30. Works great. 1 Share this post Link to post Share on other sites
gris71 12 #12 Posted January 8, 2023 Hi Bill I was thinking about doing the same thing to my kohler magnum 12 hp my fuel pump went out and really dont want to buy a cheep plastic one on ebay the qustion I have is the plate you are getting vacuum from is made out of aluminum and are you getting vacuum from were the fuel pump bolted on and did you silicone the plate on so you dont get leakage around the plate or screws thank you steve 1 Share this post Link to post Share on other sites
Bill D 1,926 #13 Posted January 8, 2023 The plate is Stainless steel. I just used regular gasket material to seal the plate to the block. The fitting lines up with the big hole in the block and is the source of the vacuum for the pulse pump. Share this post Link to post Share on other sites