WHX?? 48,654 #1 Posted June 2, 2023 So on a project here and always hesitant to get go juice flowing for the fear of where am I going to have gas spewing out somewhere. This time no different. Only two things can happen now I either put the cigarette out or throw it on the whole thing and call the insurance company... This time it was the fuel pump. ⛽️ K161 with a pulse pump. Turns out the mating halfs of the pump are so distorted that the original diaphragm was no way going to seal. Dried out and cracked after 50 years go figure. A strait edge proved that. Filed down the halfs to what I thought was a good sealing surface... first pic. No dice and replaced the diaphragm with a after market. Next try is to put the halfs on the head glass but hold no hope for this. Problem I believe is the aftermarket diaphragms are not thick enough to seal. 2nd pic notice the difference. OEM has two sealing gaskets one with the circle cut out for proper diaphragm pulse. Root of the problem is warpage of the halfs between the screws. 2 Share this post Link to post Share on other sites
Achto 27,456 #2 Posted June 2, 2023 Putting sand paper on a piece of glass and planning the surfaces won't do the trick? 1 Share this post Link to post Share on other sites
ebinmaine 67,090 #3 Posted June 2, 2023 6 hours ago, Achto said: Putting sand paper on a piece of glass and planning the surfaces won't do the trick? Yeah 👍. I've only had to do one pulse pump so far but it was badly warped. Hand planing solved it. 1 1 Share this post Link to post Share on other sites
ranger 1,741 #4 Posted June 2, 2023 If you can remove any springs, valves, etc from the housings, put the housings in a vise, (separately), with the diaphragm surface against a flat plate. Apply enough pressure to level that surface against the plate, then ‘Warm’ the housing gently with a heat gun or gas torch, and leave it to cool down. This usually removes most of the distortion, allowing you to finish off lapping surfaces flat on a sheet of wet or dry paper, (without having to remove too much material to level the surface), then do as @Achto suggests. One further thing regarding gaskets, etc, thicker gaskets, (especially rubber), can worsen leaks, due to allowing distortion to occur in between fasteners, (rubber does not compress, but distorts easily, and ‘extrudes’ out under the fastener positions), particularly if over tightened! Doug. 1 1 1 Share this post Link to post Share on other sites
Pullstart 62,653 #5 Posted June 2, 2023 Sometimes when you’re riding Uncle Jim’s tractors, you gotta give ‘em mouth to mouth… 4 Share this post Link to post Share on other sites
SylvanLakeWH 25,428 #6 Posted June 2, 2023 7 minutes ago, Pullstart said: Sometimes when you’re riding Uncle Jim’s tractors, you gotta give ‘em mouth to mouth… The @ebinmaine school of fuelology... 1 1 Share this post Link to post Share on other sites
ebinmaine 67,090 #7 Posted June 2, 2023 2 minutes ago, SylvanLakeWH said: The @ebinmaine school of fuelology... YESSUH !!!! 1 Share this post Link to post Share on other sites
WHX?? 48,654 #8 Posted June 2, 2023 2 hours ago, ranger said: particularly if over tightened! Doug. Guilty as charged Doug. Going to try the above suggestions... thanks. 1 Share this post Link to post Share on other sites
rmaynard 15,393 #9 Posted June 2, 2023 I have rebuilt a few pulse pumps. Only a few have needed to be resurfaced. I use Brian's (buckrancher) diaphragms. However, the one on my K161 that I recently rebuilt had problems with leaking, even with a new diaphragm and surface planing. So I put a little bit of yellow Teflon thread sealer on both surfaces. It worked. 1 1 Share this post Link to post Share on other sites
JoeM 7,871 #10 Posted June 2, 2023 53 minutes ago, Pullstart said: you gotta give ‘em mouth to mouth No that is mouth to snout! A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. The wet furless surface around the nostril is the fuel pump! And in Uncle Jim's case the "wet furless suface" is warped! 5 Share this post Link to post Share on other sites
peter lena 8,560 #11 Posted June 2, 2023 @WHX?? https://www.walmart.com/ip/CarBole-12V-Universal-Electric-Fuel-Pump-2-3-5PSI-Low-Pressure-Micro-42S-28-GPH/972444636 have 2 of these on , my horses now , after swapping out a bad pump with a new diaphram pump I had , that also had went south with little use . these car bole pumps are very quiet / solid , low pressure , good price . also added a single LED dash light on my first electric pump , to verify its working . hook up to run on ignition switch , monotors itself . also added a fuel check valve , line is always visibily full of fuel . probably swap over my last horse as well . dash light is single green bulb . anything I suggest has been in use and reliably works . gassy pete 4 Share this post Link to post Share on other sites
squonk 40,950 #12 Posted June 2, 2023 Had the same issue years ago. Aftermarket diaphragm was too stiff to work correctly. Had to get one from Brian. 1 Share this post Link to post Share on other sites
WHX?? 48,654 #13 Posted June 2, 2023 (edited) 32 minutes ago, squonk said: Had to get one from Brian. That's where mine come from. More on order. Thanks for the post Greasy but electric would be NA for a 701 resto. Something just wouldn't be right about that... Make matters worst the sentimental bowl Dan INSTISTED I use does not shut off 100%. Edited June 2, 2023 by WHX?? 6 Share this post Link to post Share on other sites
squonk 40,950 #14 Posted June 2, 2023 All you need is a little "Nascar Ingenuity" and hide an electric. I know I know. Gotta have it Original so you hafta tinker with it all the time! I got stuff "hidden on my 1467 Special. One of them will loosen tooth fillings! 2 Share this post Link to post Share on other sites
ranger 1,741 #15 Posted June 2, 2023 Possibly an easier solution could be, Roughening of the surfaces between the screw holes, the generous application of 24hr ‘JB Weld’, allow to cure, then lap the faces with wet or dry paper on a surface plate or equivalent. Doug 1 Share this post Link to post Share on other sites
Racinbob 11,014 #16 Posted June 2, 2023 5 hours ago, WHX?? said: That's where mine come from. More on order. Thanks for the post Greasy but electric would be NA for a 701 resto. Something just wouldn't be right about that... Make matters worst the sentimental bowl Dan INSTISTED I use does not shut off 100%. Jim, do you need another pulse pump for the body? I have one off my 854 that I won't be using. Share this post Link to post Share on other sites
WHX?? 48,654 #17 Posted June 2, 2023 33 minutes ago, Racinbob said: Jim, do you need another pulse pump for the body? I have one off my 854 that I won't be using. I do not Bob I have a spare that Dan hid in the shop somewhere. I found it but the good news is glassing it did he trick and it sealed up nice. Still no fire in the hole tho. Starter generator has got issues. Stalls on compression stroke. Just downloaded the SG manual from @pfrederi and will be seeing if can be saved. 1 Share this post Link to post Share on other sites
squonk 40,950 #18 Posted June 2, 2023 (edited) 5 minutes ago, WHX?? said: Still no fire in the hole tho. Starter generator has got issues. Stalls on compression stroke. Just downloaded the SG manual from @pfrederi and will be seeing if can be saved. Clean all the paint you slathered on the block where that genny mounts and on the mount too. When I built my engine run stand I reduced voltage drop by a volt just by cleaning dirt, paint and rust off the surfaces and bolts. Small blocks draw 60-80 amps on initial rotation. Edited June 2, 2023 by squonk 1 Share this post Link to post Share on other sites
JoeM 7,871 #19 Posted June 2, 2023 1 hour ago, ranger said: the generous application of 24hr ‘JB Weld I have had great success with MotoSeal Permatex MotoSeal Gasket Maker Grey was designed for two and four cycle engines Ideal to use on motorcycle case halves and carburetor gaskets. It forms a solvent based, tough, flexible bond within 20 minutes. This unique Gasket Maker forms a tough flexible bond that is highly effective on irregular or uneven joint surfaces. 1 1 Share this post Link to post Share on other sites
WHX?? 48,654 #20 Posted June 2, 2023 (edited) 4 hours ago, squonk said: Clean all the paint Been there done that. Suspect bad armature but I don't have the test equipment to verify it. Going to a pro shop that can do everything I can't. https://www.fondyautoelectric.com/ Funny you should mention that stuff @JoeM. I did use a smidge of it for insurance. Mine does not say motoseal tho? I got it for a 5hp Briggs where the tank is right on the bottom of the carb. Didn’t work ... other underlying issues tho. Edited June 2, 2023 by WHX?? Share this post Link to post Share on other sites