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Discussion Starter #1
So here's my story: Recently picked up what I believe is a '67 Gravely C8 with several implements (see pics below). Doesn't want to start, so I did some of the non-invasive stuff - oil filter change, new air filter, spark plug (adjusted gap), cleaned out oil fill cap, new main gas shutoff valve. Still no deal.

Fuel is getting to the carb. How do I know? Because it is dripping from the orifice on the bottom of the carb (see pic). There is something solid in this hole, but I'm not sure if it is a sheared off bolt or what.

My questions are these: How do I know if the carb needs rebuilding or replacing? In either case, how do I identify which Zenith carb this is (no tag)?. What should I check next to troubleshoot non-starting issue?

Thanks in advance for any help and let me know if you want more pics.
 

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First thing does it get a spark if so taking the carb apart and cleaning should solve fuel issues if it has a spark spray a shot of ether in the carb and try to start it should at least run for a short time if not could be something more probably should check the compression at that point.

Good luck Dave
 

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First off, nice looking tractor. Hood looks in good shape, electric start, a 106 mower, sulky, cultivator. You are well on your way to a Gravely addiction!

I second what Dave says about checking spark. That is the first place to start on anything that has been sitting for awhile.

The hole in the bottom of the carb is doing what it is supposed to do. It is a sintered metal plug that allows excess gas to drip out. Don't worry about that. The fact that you have gas dripping means that you most likely have fuel, just not fire.

Seeing that you have an electric start, your diagnosis is a bit easier. After you crank it over a short bit, pull the plug. Is it wet? If it is the fuel is not an issue right now. You can pull the plug, lay it on the head and bump the starter over. Do you have a nice fat blue spark?

Check the spark and post back. With all of the help around here we'll help you get it going in no time.
 

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Discussion Starter #4
Alrighty. Cranked it over a few times and pulled the plug. It's wet. Plugged the wire back in, laid it on the head and cranked. Spark is there, but not what I would describe as "strong or blue". More like "white and weak". Thoughts? Magneto? Point adjustment?

Thanks again. I'm very motivated to get this beast running well and I'm already looking at a second one. Sigh...
 

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My thoughts would be to ditch the old plug and just purchase a new one (in fact, a few new ones - go with Autolite). Drain out all of the old gas in the tank and the carb - replace it with fresh stuff. And purchase some brand new 1/4" fuel line and replace all of the existing lines with it - before you try to fire her up again. Also, purchase one of the larger 1/4" fuel line fuel filters (not the midget one) and install that as well. Usually doing these things will get you in the ballpark.
 

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Discussion Starter #6
New plug got it closer to starting, but still no luck. There is only the one 1/4" fuel line, correct? Blew that out with air. Set main jet and idle adjustment to manual specs. Drained out the old gas and replaced with new. Copious amounts of white smoke when it tries to catch. Any ideas?
 

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Copious amounts of white smoke when it tries to catch. Any ideas?
Burning oil. If it's smoking that much just when trying to catch, I'm guessing either oil built up in cylinder and you're burning it out, or the rings are badly stuck or worn.

If the PO put a bunch of oil in there when he put it up, that's a good thing, and you just need to get it started. Once it runs for a few minutes it will clean itself out. If the rings are stuck, ditto, they may unstick once you run it through a few heat cycles.

If they're that worn, you can replace them, parts are readily available. However you might also be looking at boring to the next oversize, new piston etc.

Get it running first, let it get hot, then decide what you're dealing with.
 

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My first thought when you said that gas was dripping out of the bottom of the carb is that the float was stuck causing the main needle to not close. If that is the case, it might be flooding itself.

I agree completely with JRD on the oil. That might be the culprit as well.
 
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