Sparky-(Admin) 21,300 #1 Posted July 17, 2020 Took apart a plastic body fuel pump that isn’t pumping. All looks good? What’s with the part where the little spring is? Doesn’t seem to move in or out. Can someone school me on this? Share this post Link to post Share on other sites
Ed Kennell 38,022 #2 Posted July 17, 2020 I'm not familiar with this pump Mike, but hat appears to be a simple spring loaded check valve. It should allow flow toward the hex and the spring should prevent flow away from the hex. If you pull the spring, does the seat lift or is it maybe gummed fast and not opening? Share this post Link to post Share on other sites
Sparky-(Admin) 21,300 #3 Posted July 17, 2020 5 minutes ago, Ed Kennell said: I'm not familiar with this pump Mike, but hat appears to be a simple spring loaded check valve. It should allow flow toward the hex and the spring should prevent flow away from the hex. If you pull the spring, does the seat lift or is it maybe gummed fast and not opening? Ahhh...maybe that’s what it does. Back to the garage I go. Thanks Ed! Share this post Link to post Share on other sites
Lee1977 6,642 #4 Posted July 17, 2020 I don't believe that spring has anything to do with the pumps operation. Looks way too stiff to operate the check valve. There are two check valves the inlet lets it in but not back out. The out let it out but not back in, both work with the diaphragm. Share this post Link to post Share on other sites
Sparky-(Admin) 21,300 #5 Posted July 17, 2020 So after installing it and removing it and dismantling it and reassembling it a few times I gave up . Neighbor had a messed up semi-taken apart 300 series with a Magnum and offered me the fuel pump. It looked crusty, been outside for a few years without a hood and one of the hoses was stickin straight up catching rain water. Well I cleaned it up and made a gasket with some scrap cardboard and it WORKS!! This is the first time I’ve heard this motor run. Sputters a bit, will need some carb tweaking/cleaning. 1 2 Share this post Link to post Share on other sites
Bill D 1,907 #6 Posted July 17, 2020 I say go this route. I did this on my dad's tractor and it's working great. Bill 1 Share this post Link to post Share on other sites
roadapples 6,983 #7 Posted July 17, 2020 You said it WORKS! You haven't told us what "it" is.... Share this post Link to post Share on other sites
SylvanLakeWH 25,490 #8 Posted July 17, 2020 Details please! Share this post Link to post Share on other sites
Bill D 1,907 #9 Posted July 17, 2020 It's a vacuum impulse pump and mounting plate. Share this post Link to post Share on other sites
Stormin 9,981 #10 Posted July 17, 2020 Looks like a Pacet vacuum pump. Share this post Link to post Share on other sites
johnnymag3 2,515 #11 Posted July 17, 2020 I think he wants to know how it gets the vacuum part to function John Share this post Link to post Share on other sites
johnnymag3 2,515 #12 Posted July 17, 2020 Ya know....Da DETAILS Share this post Link to post Share on other sites
Back on a horse 55 #13 Posted July 17, 2020 (edited) That is a vacuum pump that uses the pressure pulses produced inside the crankcase for operation. I just ordered all the parts to do this, but am still worried that the diaphragm inside that "cheap" chinese pump will fail and allow gas to mix with the oil. Because of that, I am still considering getting an electric pump so I can be done with worrying about destroying my Kohler engine. Edited to correct myself .... the pumps can be sourced from Japan ... Briggs, Kawasaki and Mikuni Edited July 17, 2020 by Back on a horse 1 1 Share this post Link to post Share on other sites
Bill D 1,907 #14 Posted July 17, 2020 (edited) The plate mounts to the engine block with a gasket. The brass fitting connects the the pulse port on the pump with a piece of 1/4" fuel hose. The fitting on the lower right of the pump is the fuel intake from the tank. The fitting on the left of the pump is the outlet. Pump is Briggs PN 597338. Kawasaki PN 49040-7008 will also work. The pulse line and outlet on the Kawasaki pump are in different locations that may make connections easier. The Briggs pump is made in Japan. Edited July 17, 2020 by Bill D 1 Share this post Link to post Share on other sites
johnnymag3 2,515 #15 Posted July 17, 2020 I do understand his point about the crankcase getting fuel in it...are there any provisions against that happening??? It would make a grown man cry to know he fed gasoline to a Horse ........in the wrong place John Share this post Link to post Share on other sites
Bill D 1,907 #16 Posted July 17, 2020 No there isn't. If you use a good quality, name brand pump there should be no more risk than using the OEM mechanical fuel pump. Share this post Link to post Share on other sites
johnnymag3 2,515 #17 Posted July 17, 2020 Just now, Bill D said: No there isn't. If you use a good quality, name brand pump there should be no more risk than using the OEM mechanical fuel pump. I think thats what the issue is, so maybe he would be better with a mechanical pump to ease his mind, and the chance to ruin his engine. Chances are it wont, but some of us like that comfort zone knowing it cant happen.... To Each His Own ....!!!! Share this post Link to post Share on other sites
johnnymag3 2,515 #18 Posted July 17, 2020 I do like your adaptation though...looks neat and sleek Share this post Link to post Share on other sites
johnnymag3 2,515 #19 Posted July 17, 2020 and works perfect....another plus Share this post Link to post Share on other sites
Back on a horse 55 #20 Posted July 17, 2020 (edited) Bill, thanks for letting me know that is a Japanese pump. I was not able to find a part number anywhere before I ordered and I didn't get a chance to watch the Taryl video. I just found a Mikuni pump like yours online and my office mate says they make great pumps and it has great reviews. I"ll have to think on this a little more. Edited July 17, 2020 by Back on a horse Share this post Link to post Share on other sites
Bill D 1,907 #21 Posted July 17, 2020 You may want to try the Kawasaki pump. The outlet is on the top left which would make for a cleaner install. Not sure who makes it for Kawasaki. Share this post Link to post Share on other sites
Back on a horse 55 #22 Posted July 17, 2020 Bill, does your vacuum pump maintain prime fairly well? Share this post Link to post Share on other sites
Bill D 1,907 #23 Posted July 17, 2020 So far so good. I put it on my dad's tractor. I think he's only used it once since I installed it. Most modern tractors use these pumps and they start fine after sitting for a week or more. My neighbor has a GT1142 with this pump on it and it starts and runs great after sitting all winter. My GT1642 has a pulse type pump built into the carb and it's always started easier than my Kohler's. Share this post Link to post Share on other sites
RAM 22 #24 Posted July 19, 2020 Hello Bill, I recently replaced my mechanical fuel pump with a Briggs (Mikuni) vacuum style pump on a 310-8. Original problem was mechanical pump not pumping. Tried new cheap pump that worked once and stopped working so I went to the vacuum pump. Also replaced all fuel lines. There was no fuel filter in the system and there is still no fuel filter. My question is now the engine runs great but has long crank times when cold starting. If warm starts right up. What could the issue be - vacuum leaks, carb dirty? Where to go next. Don't want to destroy my starter. Ron Share this post Link to post Share on other sites
RAM 22 #25 Posted July 19, 2020 Nice plate installation by the way. Great idea to create a mounting point for the pump. Share this post Link to post Share on other sites
