656 gas starting problems

mazdmec1

New User
I have owned this 656 gas tractor for about 3 weeks now. It has ran fine up until now. The other day the tractor died and I thought it was out of gas. I added some gas and it took a bit but it started back up. I parked it and when I tried to start it a couple days later, it would not start. Before I bought it, the previous owner had the fuel tank cleaned out and the carburetor rebuilt by a Case/IH dealer. It acted like it wasn't getting any gas as I could get it to pop off with ether. I pulled the carburetor and cleaned it out. It had a bit of rust in it, but not a whole lot. Put carb back on and still will not start. Pulled the plugs out and they were a bit wet. Cleaned the plugs, drained the engine oil and tried to start. Still no luck. I checked the compression and all but one cylinder is at 160 psi. One is at 145 psi. I also plugged a vacuum gauge in at the fitting just above the carburetor and I am not building any vacuum while cranking. Pulled the carburetor back off and there is quite a bit of gas running out of the carb inlet and the intake manifold. I am not sure what the compression should be, but 160 psi should pull the fuel in. I am sure there is something I am missing, but just can't think of it right now. Any ideas would be greatly appreciated.
 
Check to see if you have a good spark at each plug.
Check the points to see if they maybe need replaced, then
go at the fuel area.
Jim
 
checked the spark and it is real good. I am wondering if the cylinder walls have washed down and has lost enough compression to not draw the fuel into the cylinders.
 
(quoted from post at 08:05:24 01/29/17) checked the spark and it is real good. I am wondering if the cylinder walls have washed down and has lost enough compression to not draw the fuel into the cylinders.

I cant imagine 145/160 lbs of compression not being enough to draw in fuel. I would make sure your getting fire to the plugs. Is it possible the dist cap got turned 180 degrees?
 
To check for proper draw on the intake simply hold your hand over the intake of the carb while someone cranks the engine. If it sucks against your hand that is not the issue. A vacuum gauge on a cranking engine is not that great of a diagnostic tool on a tractor because the governor will not always hold the throttle tight to the idle stop when the engine is stopped. Those tractors originally had a main jet shut off solenoid on the bottom of the carb. That cuts fuel flow to prevent "run on dieseling" when shutting the engine off. That will need power with the key on and has to be working properly for the tractor to run. However I would think the engine would still start and run at least a few second on the choke enrichment circuit even if the solenoid was not working properly. I'm kind of leaning toward an agreement with old450 that you may have clipped the dist. cap on 180deg out, double check that.
 
One more thing; if there is an aftermarket in-line fuel filter on the fuel line go out there now, take it off, and throw it as far away as you can! Get some metal tubing and splice the fuel line back together and don't tell anyone about the inline filter. They are WORTHLESS on gravity fuel systems.
 
I wouldnt think that it was 180 out. I ran it for a couple of hours and used it pretty hard and it was running very well. It has good spark. I
just can't figure out why there is so much fuel in the intake. I double checked the float and it isn't set too high.
 
I believe you are getting flooded since you say gas is laying in manifold. Your plugs were all wet when you pulled them to check compression,and you found rust in the carb.The rust may be in the needle and seat,keeping it from stopping gas flow.Or your float is full of gas and won't float.I would turn off the gas at the tank,leave the carb on the engine,and take the bottom/float bowl off the carb.Turn on the gas and gently lift the float up and see if the gas flow stops.If it does,check your float to see if it floats.If you remove it on the engine,as I would,be sure to catch the needle.You can shake the float also to see if gas got in it.Also that short time of flooding would not wash down the cylinder walls enough to hurt anything.Let us know what you find.Mark
 
One other thing comes to mind,but I doubt it is your problem.Maybe the intake manifold gaskets are blown,and that is why you had no vacuum reading.But check the carb out first.Mark
 

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