MAD MARK 74 #1 Posted August 18, 2018 (edited) Bought a 314-H running as is. Changed gas out, new air filter, new spark plug. Ran great for 2 weeks. Parked a week. Now won't start. No spark. -Found out bad coil, put new one in. -Cleaned all contacts/grounds Maybe bad gas still -Took tank off flushed 4 times with fresh gas. -All new fuel lines -Cleaned carb -New fuel pump -Have even tried working pump off another tractor. It seems the fuel pump is weak. Almost like the cam or whatever "strokes" it isn't hitting the full length. The fuel doesn't squirt like other tractors. Same EXACT fuel pump model from where it was running fine. -Will run on ether/carb cleaner fluid. Thoughts?? Edited August 18, 2018 by MAD MARK Share this post Link to post Share on other sites
JAinVA 4,619 #2 Posted August 18, 2018 Expose the air cleaner and dribble gas on the air cleaner.You don't need much.Crank the engine with choke off.Does the engine fire.If it does then it's fuel delivery.If I doesn't fire then it's the ignition system. Share this post Link to post Share on other sites
MAD MARK 74 #3 Posted August 18, 2018 I believe the ignition to be working fine. After swapping, then buying a new coil it will fire at will with starting fluid. The fuel system seems bad. Next step is trying an electric pump. But like to keep what I have. Share this post Link to post Share on other sites
r356c 375 #4 Posted August 18, 2018 (edited) Pull the fuel hose from the tank and check the gravity fuel flow into a jar or other container. Crud buildup in the shutoff valve? The shutoff valve is fully opened counter clockwise to the stop? (Had to ask.) Work downstream from there. It is a fuel delivery issue. One more time through the fuel system! Edit Add: When checking gravity fuel flow from the tank, I start with the fuel cap loose. If that seems good, I will tighten the cap and let a cup or so more drain out to see if the air vent holes are clogged in the cap itself. Edited August 18, 2018 by r356c 1 1 Share this post Link to post Share on other sites
MAD MARK 74 #5 Posted August 18, 2018 Brand new fuel shutoff forgot to mention. And yes it flows greatly from there. My running 312-H I take off the fuel pump which squirts good with pump to carb hose off, put it on the 314-H and it barely pumps anything through pump. Share this post Link to post Share on other sites
r356c 375 #6 Posted August 18, 2018 One of these, correct? Share this post Link to post Share on other sites
MAD MARK 74 #7 Posted August 18, 2018 I have tried one of those. And I have tried the OEM off the 92 312-H. Share this post Link to post Share on other sites
r356c 375 #8 Posted August 18, 2018 Right about now I would be trying the gravity feed IV fuel bag trick straight into the carb to see if an electric fuel pump was in my near future. A worn lobe for the fuel pump actuator arm or a too thick spacer between the pump and block are a few other thoughts. 1 Share this post Link to post Share on other sites
MAD MARK 74 #9 Posted August 18, 2018 (edited) I was leaning towards worn arm. But I searched the forums and saw that as a thought but, never the end cause. I will try a direct gravity feed into carb. If runs good, I see an electric boogie woogie going in. Edited August 18, 2018 by MAD MARK 1 Share this post Link to post Share on other sites
r356c 375 #10 Posted August 18, 2018 Gatorade bottles are fuel proof. I've been storing my 2-stroke mix in them for years... A good choice for a fuel IV bag container. 1 Share this post Link to post Share on other sites
953 nut 51,541 #11 Posted August 18, 2018 I have used these electric pumps off Ebay on three of my for several years and had good results. Less than $ 10.00 delivered to the house. I will PM the link. 2 Share this post Link to post Share on other sites
MAD MARK 74 #12 Posted August 18, 2018 Thanks, I ordered one just to have it on the way even if I do figure it out. 2 Share this post Link to post Share on other sites
dells68 7,494 #13 Posted August 18, 2018 4 hours ago, 953 nut said: I have used these electric pumps off Ebay on three of my for several years and had good results. Less than $ 10.00 delivered to the house. I will PM the link. I just got two of these from the li k Richard is referring to and they are very nice. They are some of the quietest pumps I've ever used! 1 Share this post Link to post Share on other sites
MAD MARK 74 #14 Posted August 23, 2018 Update. Tractor runs. Haven't tried full throttle but started 2 times no issues using the electric pump through the stock fuel pump. Is that a bad idea to keep it set up like that or should I bypass stock pump? With engine running I cant hear the electric pump, with it off it's kinda noisy. Hooked up electric pump temporarily. Turned key, tractor started, unhooked pump and it kept running. Thinking maybe I'll just use it as a "prime" pump? 1 Share this post Link to post Share on other sites
953 nut 51,541 #15 Posted August 23, 2018 I bypass the mechanical fuel pump. If the diaphragm developed a leak you would be pumping gas into the crank case. 1 Share this post Link to post Share on other sites
bds1984 1,382 #16 Posted August 23, 2018 I went through the same issue a couple years ago with a rescued 312-8 and tried all the "usual" fixes. The culprit: there was a second gasket on the fuel pump which prevented the pump arm from achieving a full stroke. Share this post Link to post Share on other sites
cleat 4,936 #17 Posted August 23, 2018 You really need a full stroke 1 Share this post Link to post Share on other sites
MAD MARK 74 #18 Posted August 23, 2018 I did just read something today about not using both the felt gasket and the squiggly one together. Maybe that's the problem with the newer mech pump. Share this post Link to post Share on other sites
953 nut 51,541 #19 Posted August 24, 2018 Question from @MAD MARK that was PMed to me. I mover it to his post for continuity sake. Should the positive wire be hooked to constant or "start" power? I've been getting it running by touching the starter relay constant side, but then disconnecting it and it keeps running. Only done this in garage so might be a gravity draw with tank half full? The positive wire of your electric fuel pump should be connected to the accessory circuit, this is the same circuit your lights are connected to. If you pull the dash plate off you can connect the pump directly to the wire that goes from the ignition switch to the light switch. This manual has a wiring diagram for your tractor. Share this post Link to post Share on other sites
MAD MARK 74 #20 Posted August 24, 2018 Alright I had the wiring diagram already and was using that but seems some colors are different. No big deal I can follow the jest of it. I did in fact use the pink wire "accessory" but hooked in closer to the fuse block for ease of access. Thanks. 1 Share this post Link to post Share on other sites