peter lena 8,970 #1 Posted February 21, 2022 this is the set up I use on my kohler magnum engines , the check valve is a 5/16 " size , fits snugly into a 1/4 " ID , clear fuel line , use the dark green small squeeze clamps , also use super lube or a light swipe of dielectric grease on the valve end stubs , make it slide / screw on exactly size to size . I put this together before installation , makes it easy , the arrow should be vertically in the up position , between fuel pump and carb . that will trap a fuel charge for quick starts , of course if your fuel pump is weak , that will not help . but this makes for instant starts , and very little choke , pete 6 Share this post Link to post Share on other sites
peter lena 8,970 #2 Posted February 21, 2022 @oldlineman ,https://www.amazon.com/EVIL-ENERGY-Return-Petrol-Aluminium/dp/B07ZB42CGT good source on those valves . very little choke , as compared to before valve , pete 2 Share this post Link to post Share on other sites
pfrederi 18,178 #3 Posted February 21, 2022 Why does 5/16 fit into 1/4" tubing?? 1 Share this post Link to post Share on other sites
WHX?? 49,917 #4 Posted February 21, 2022 22 minutes ago, pfrederi said: Why does 5/16 fit into 1/4" tubing?? It's a stretch. They also offer them in 1/4 .... https://www.amazon.com/gp/product/B01C3PD06K/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Looks like their out of them tho. @formariz commented on them awhile back so what the heck try anything once. I'm on the fence about them unless I got some bad ones. Three 520s with them and all start dry after a sit. A shot of sniffin salts is in order if they sat along time and away they go tho. I put it in just before the pulse pump but @cschannuth's 520 It's after the pump so location does not matter unless it should be way down by the tank Now @dclarke's 520 he's got one of them newfangled electric jobbys on it. Turn the key and wait maybe 15 seconds and listen for the pump to load up and she fires right off. No check valves here. Makes me a believer in E pumps that's fer sure. 1 hour ago, peter lena said: also use super lube or a light swipe of dielectric grease How does this not surprise us?!?!? 3 Share this post Link to post Share on other sites
SylvanLakeWH 26,587 #5 Posted February 21, 2022 50 minutes ago, pfrederi said: Why does 5/16 fit into 1/4" tubing?? That’s easy… Cuz @peter lena keeps it greasy… 1 4 Share this post Link to post Share on other sites
squonk 41,928 #6 Posted February 21, 2022 I tried one. It worked about as well as a Lube and those tinny clamps on a fuel line? No Thanks 1 1 Share this post Link to post Share on other sites
peter lena 8,970 #7 Posted February 21, 2022 (edited) @pfrederi very simple , the 3/8 OD of a clear fuel line , covers the I D of 1/4" snugly fitting a 5/16 fuel barb , no leaks no issues , have it on 3 engines , instant starts , no leaks , correct size spring clamps , put spring clamps on the line before sliding on the hose , then lineman's plyers to install , simple ,easy . thanks for the kind words , pete Edited February 21, 2022 by peter lena 2 Share this post Link to post Share on other sites
wallfish 17,191 #8 Posted February 21, 2022 So far the go to solution for me is a simple primer bulb. They have check valves in them too as that's how they work to push fuel forward. Instant starts and if it sits for a very long time (Like over the entire summer) just a couple squeezes and it's ready to go. No squeezes necessary if it sits for a week or 2. I've tried those little check valves too and didn't have much luck either and especially so after it was sitting for a longer while. My guess is gas can seep past the little ball bearing seal inside. If it sits for months or if the tank is drained then it's a problem cranking the starter for a long time to start them. A little check valve isn't going to help with that when the tank was drained or empty. If that hard start doesn't happen then that is a good sign the fuel pump is working well and therefore the check valves in that pump are holding good, so no extra check valves are needed anyway. Once a fuel pump has failed or not working very well because the check valves inside the pump aren't sealing, then I go to the electric pumps. No grease or anything on my done dry fuel line connections and they're still very easy to do with a nice tight seal. 3 1 Share this post Link to post Share on other sites
peter lena 8,970 #9 Posted February 21, 2022 @formariz just curious , are those fuel check valves installed IN A VERTICAL POSITION ? WITH ARROW FLOW UP? my 3 consistently instant start my kohlers . fuel pumps ok ? pete 1 Share this post Link to post Share on other sites
wallfish 17,191 #10 Posted February 22, 2022 1 hour ago, peter lena said: instant start my kohlers My Kohlers seem to start easier and better than the Onan. Only have one. But that Onan does fire up quick when the carb bowl is full. Maybe it's just because the Kohlers are more familiar to me Also prefer a mechanical fuel pump over the vacuum pulse pumps too. I have a few of those check valves from years ago and just blew some air through one. They don't use balls in them, it's a flapper type valve. 1 Share this post Link to post Share on other sites
formariz 11,991 #11 Posted February 22, 2022 1 hour ago, peter lena said: @formariz just curious , are those fuel check valves installed IN A VERTICAL POSITION ? WITH ARROW FLOW UP? my 3 consistently instant start my kohlers . fuel pumps ok ? pete Correct. They are vertical arrow up. I try to have them as close to carburetor as possible. They do work. What i notice however is that since a carburetor is not really a closed sealed system when tractor sits for a while there will be evaporation from carburetor. Valve of course will keep fuel closer to carburetor making it easier on fuel pump. Only an electric fuel pump will surpass all of those issues. I have experimented all kinds of stuff regarding these issues. My tractors usually sit at an incline not always in the favorable position. I have been thinking since I have a few electrical fuel pumps that put out too much pressure to use them as just a starting pump as @wallfish described in a previous post. 1 Share this post Link to post Share on other sites
WHX?? 49,917 #12 Posted February 22, 2022 2 hours ago, squonk said: those tinny clamps on a fuel line? No Thanks I use them tinny clamps all the time Squonky with no issues... must be just you ..... well except for those original gotta have old skool cool sediment bowls you keep pushing..... 2 Share this post Link to post Share on other sites
peter lena 8,970 #13 Posted February 22, 2022 @formariz have this one on my c85-12 ,https://www.walmart.com/ip/42S-Universal-Micro-Electric-Fuel-Pump-2-3-5-PSI-Low-Pressure-Gas-Gasoline-12V/640043909? , having it run thru a green led dash light , low pressure , silent , have a few years on it now , no issues . run 2 gas filters on my stuff , 1 close to tank , another close to carb . no fuel issues , put stabil in all my stuff , every time i top off , add a couple ounces , no ethanol issues at all . carb bowls , clean no debris , pete 3 Share this post Link to post Share on other sites
WHX?? 49,917 #14 Posted February 22, 2022 (edited) 2 hours ago, peter lena said: @pfrederi thanks for the kind words , pete Your Pete.... your greasyness is welcome here anytime and keeps us on our toes. 2 hours ago, wallfish said: So far the go to solution for me is a simple primer bulb. I hear what yer sayin 'Fish but call me a purist, a moron, a idiot ....yep I got it coming but them things belong on outboards and not horses. I praise the Kohler gods every time a tractor comes in with a manual primer on the fuel pump and quickly stash it. Onans might be the best but with your comment I'm gonna feel like I'm squeezing something under your seat every time I squeeze.... never mind.... Edited February 22, 2022 by WHX?? 2 Share this post Link to post Share on other sites
wallfish 17,191 #15 Posted February 22, 2022 23 minutes ago, WHX?? said: Your Pete.... your greasyness is welcome here anytime and keeps us on our toes. I hear what yer sayin 'Fish but call me a purist, a moron, a idiot ....yep I got it coming but them things belong on outboards and not horses. I praise the Kohler gods every time a tractor comes in with a manual primer on the fuel pump and quickly stash it. Onans might be the best but with your comment I'm gonna feel like I'm squeezing something under your seat every time I squeeze.... never mind.... Have you ever tried one? I too miss those old primer pumps What's this about Onan being the best? Gotta love that split intake manifold to say such a thing. You must be a Teccy man too! LoL I'm considering switching the 2 stage back to the 418-C because it seems to have more power than the 20 Onan. Could be like I said though, not as familiar with them but I still know how to tune a carb no matter what engine it's on. 2 1 1 Share this post Link to post Share on other sites
SylvanLakeWH 26,587 #16 Posted February 22, 2022 5 hours ago, WHX?? said: I hear what yer sayin 'Fish but call me a purist, a moron, a idiot ....yep I got it coming but them things belong on outboards and not horses. I praise the Kohler gods every time a tractor comes in with a manual primer on the fuel pump and quickly stash it. Onans might be the best but with your comment I'm gonna feel like I'm squeezing something under your seat every time I squeeze.... never mind.... Visuals and name calling aside… The primer bulbs work great… cheap, easy and functional… built in check valves and they always work… 1 1 1 Share this post Link to post Share on other sites
WHX?? 49,917 #17 Posted February 22, 2022 12 hours ago, wallfish said: What's this about Onan being the best? No never tried one but it may come to that. No I meant Onans being the best candidate for the primer bulb thingy. I'd take a Kohler over an Onan any day... heck maybe even a Briggs twin! The tecky thing I'll leave for the Squonky! 1 1 Share this post Link to post Share on other sites
kpinnc 13,102 #18 Posted February 23, 2022 21 hours ago, SylvanLakeWH said: The primer bulbs work great… cheap, easy and functional… built in check valves and they always work… Agreed. I like the idea of a check valve. I'll probably try one too. But so far, the primer bulb is great on everything I have with a fuel tank under the fender. Just how much longer my batteries last is reason enough to use one. Both solutions offer the same result: everyone likes a 40-50 year old engine that fires on the first revolution. 5 Share this post Link to post Share on other sites
lynnmor 7,478 #19 Posted February 23, 2022 I bought those check valves a couple of years ago, they don't seem to do a thing. Maybe it would help if I got around to installing them. Since the jury is still out about their effectiveness, I didn't get too excited about following thru. 1 1 Share this post Link to post Share on other sites
peter lena 8,970 #20 Posted February 27, 2022 @dmoore picture of the fuel check valve already in line , just cut it down to the same size of your fuel line from fuel pump to carb ,note the dark colored spring clamps , thats the size to size clamp you want . local h/w store. I put a very small amount of dielectric grease on the sides of the sliding hose barb fittings , that hose is size to size , 1/4 " ID . put clamps on hose ,slide them up out of the way . mount new hose/ valve set up , then just squeeze and slide them down to hose barb . make sure you have VALVE FLOW facing up to carb , ARROW UP . this consistently works . instant starts , for me . all 3 of my kohlers have this , just moved more snow , pete Share this post Link to post Share on other sites
peter lena 8,970 #21 Posted February 27, 2022 @dmoore top picture of this response , is my picture of check valve in fuel line set up , just cut it down to duplicate the original fuel line to carb length , and install it . title is FUEL CHECK VALVES , PETE 1 Share this post Link to post Share on other sites
dmoore 929 #22 Posted February 28, 2022 Good info here! Thanks to all who chimed in. I'm going to try a primer bulb first because I just happen to have a new one. I'll report back after the test.👍 2 Share this post Link to post Share on other sites
Wheelhorse#1 1,738 #23 Posted February 28, 2022 (edited) These check valves don’t hold gas.At least mine didn’t.I hooked one up and left the top end ,above the arrow,open. I cycled gas through it via fuel pump, then shut it off. I watched as the gas slowly worked it’s way back down the gas line below the check valve. If you think about it gas os going to stop at the pump anyway, just a couple inches from the carb. Maybe I’m just lucky, all three of my K series’s Kohlers start just fine with out those valves.They need a bit of choke when it’s cold ,normal. Just wondering if folks just need a fuel pump rebuild and cleaning but don’t realize it? Edited February 28, 2022 by Wheelhorse#1 1 Share this post Link to post Share on other sites
