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Discussion Starter · #1 ·
Howdy all and Merry Christmas.
A buddy has a JD 350 that quit in the woods. It was running very rich, so he brought the carburetor to me to rebuild. It was set very rich before disassembling. The flange that bolts to the intake was warped too. I flattened the flange, rebuilt the carb and set the mixture screws at 1 turn out each. While I was doing that, he went to the Deere dealer for a full tune-up kit and installed it. Points and coil have good spark, but the spark at the plugs seem weak to me. Great vacuum at the intake side of the carb. After trying to start it, some gas will flow out of the carb. Plugs will still be dry. I tried some starter fluid while turning, still nothing. I could smell the fluid from the exhaust pipe. Still not so much as a pop.
What am I missing?
 

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Well, if spark seems weak, that would cause it to not fire, but you also say they are dry with some gas coming out of carb, which makes no sense to me, particularly if the rest of the engine hasn't been worked on.
 

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You have spark, fuel in the carb, and smell of un burnt ether in the exhaust. Seems really odd.

If the spark is too weak, or won't fire at all, you'll get unburnt fuel in the cylinders. Did the tune up kit come with the correct plugs? I've had a small mower engine tune up kit come from the manufacturer with overly long plugs that would hit the piston tops. There were two head designs used on that engine one required a short plug the other a long plug. And no where was it noted. Just check everything.

Got everything wired OK? A long shot, but is there anything like a ballast resistor or ignition control module on this engine?
 
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Discussion Starter · #4 ·
Just got back from the woods. What I found out today was he was messing with the timing, so I followed the manual to get it close. I also found out that he ran the tank out of gas. When I opened up the carb, it looked like orange koolaid. I got that cleaned again. With the carb off, he cranked it a couple of times to flush the gas in the line, and it popped through the exhaust a couple of times. That is more than we had before.
Wiring, oh my. It does have an external ballast resister. But, he had rewired it from the switch to the resister, bypassing the original wiring. So the bypass wire from the solenoid to the coil is disconnected. He said he ran it that way all summer. There are skinned wires and terminals hanging on by 2 strands, ready to break off. I told him that I would rewire it for him when he gets it back to the shop.
Still not running, but we will try again when it warms up a little after Christmas.
 

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Ya,-- you have a major disaster on your hands there! --- I refuse to work on a mess like that after someone been in it! --- In this case--start from scratch with the ignition and wiring, the right plugs, new coil/resistor, getting it correct, then make sure timing is right, then move on to the gas problem---I would completely drain and clean the tank and carb. make sure the tank is not rotted out on top and not full of slime inside---alki gas will loosen a LOT of crap stuck inside the tank and mix with it giving you orange goo!--- just had that in a mower engine I got that had been sitting for a few years!
Good luck on your venture and keep us posted!
 

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Discussion Starter · #6 ·
I think it was running too rich before he ran it out of gas and the cylinders are washed. Not enough vacuum to draw the fuel up. I used a timing light to get the timing close and double checked the wires. We have good spark. He put some gas in the cylinders and we tried it. 2 pops out of the exhaust and 1 out of the carburetor. One or the other I would know which way to turn the distributor. So, I told him that is about all I can do with it in the woods.
 
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