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rs07

Onan Starting Problem. Please Help!

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rs07
I know that John Deere really doesn't have no place on this site, and I really hate John Deere myself, but I figured that this is the place that has all the knowledgable people, so here is the problem. I am putting a recently:( rebuilt Onan twin-cylinder 18HP engine back in a John Deere 318 for a friend of mine. The engine is installed and everything connected. It turns over, but does not start. We noticed that very little fuel is passing through the clear in-line fuel filter. We tend to believe that the fuel pump is not working properly. It is a diaphragm type pump also. However, we noticed that the fuel lines on the tractor itself, coming from the shut-off valve located on the left side dash panel, when sitting behind the wheel are hard and cracked. My question is, could there possibly be an air leak somewhere's causing the fuel pump to not be able to pump fuel to the carburetor. We think the pump itself is actually working, but we think that there does not seem to be a vacuum type affect, allowing fuel to be pumped. Please help. This problem really has me "stumped". :(

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tractormike
I rescued a bolens with a 16 horse onan engine in it and I had to install an electric fuel pump on it to get it to run. The vacuum fuel pump on the carb just wouldn't get enough gas to the carb. I have not had any trouble with it since.

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rs07
Thanks to you all for your replys. I found out the fuel pump was bad, so I replaced that. I also replaced all the fuellines going all the way back to the tank. After all this it started right up and runs great. For a John Deere :D. Thanks again!

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JR
Well, I've been working on L&G equipment for over 20 years, and even tho I'm partial to Simplicity/Allis and the 200/400 series Case-Ingersol, I have to say that the older number-series Deere lawn tractors are actually pretty decent machines. The newer STX, LX, etc are absolute junk tho. Even the guy I know that works on 'em at the local Deere dealer will admit it. I've got a couple of Deere and a Cub Cadet coming in the shop this week to work on, and I'm not really looking forward to it, but they'll put cash in my pocket, so...... John

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JP
Hey Rob, Welcome to the 'fray'! Please check your parts book & if there's a spacer inbetween the fuel pump & the block BE SURE to put it in! If you don't, it hyper extends the range of motion the pump was meant to move & will HCF (High Cycle Fatigue) the pump arm. The arm & spring will then fall into your sump. Most CCK's use the spacer, it's about 1/4" or so. Hope it helps! JP PS Electric is 'better'..........

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