Have Spark, Compression, Fuel?

TGBTG7701

New User
I have a (860 Tractor 172 gas engine) I am trying to figure out why I can not get it to start. It had a blown head gasket, pulled head, had head reworked, new head gasket, good compression now (125 psi). Installed new points, condenser, replaced coil, new plugs wires solid core, new Autolite 437 plugs, have hot blue spark when tested. I rebuilt the carburetor (marvel schebler TSX-813) master kit rebuild, all new parts, float set a 1/4" and idle jet set at 1-1/2 turns out, load jet set at about the same.

The engine was running before, it had a miss, and there was water in the oil, and compression was low on #2 & #3, but it did run.

I checked to make sure my timing was correct,(Used a vacuum gauge and line off compression tester with schrador core removed, lined up dead on with mark on flywheel) found #1 was 2 terminals over, reset distributor to #1 on cap.

I am thinking my problem is within the fuel system, I think for some reason I am flooding. My plugs smelled strong of gas, and there was raw gas where the air inlet hose (Choke Section) attaches to the carburetor when I removed it. I shut off the gas valve on the tank, and removed the drain plug on the carburetor, pulled the plugs, cleaned them.

How should I try to start it tomorrow? Before I pulled the head off, I had to just bump the throttle a little, and pull the choke just a little and it would fire right up, (Even with blow head gasket and Carburetor leaking from everywhere it could)

I am new to this type of setup, I am sure it is something I am doing wrong.

Thanks for any help
 
yes sir, rotated the engine by hand, used a vacuum gauge that shows pressure and vacuum. Rotated the engine until the pressure started to go down on the gauge, then show vacuum, the rotated it the other way back to zero.

This is basically the same thing I did.
https://www.youtube.com/watch?v=aajWrKGFnDI
 
(quoted from post at 20:50:27 10/12/19) yes sir, rotated the engine by hand, used a vacuum gauge that shows pressure and vacuum. Rotated the engine until the pressure started to go down on the gauge, then show vacuum, the rotated it the other way back to zero.

This is basically the same thing I did.
https://www.youtube.com/watch?v=aajWrKGFnDI
The way you explained it you timed it tdc on exhust stroke. If you want to use a pressure-vacuum guage to find tdc of compression stroke,turn by hand until #1 cyl begin's building pressure,remove guage from hole to alow pressure to escape then continue turning until you can see/feel piston at tdc. Flywheel timing mark should be at tdc and rotory button should point to #1 plug wire. It will start from there but you should use a timing light for final setting.
 
Got it going, runs really good now, just bump the key and it fires right up. It was timing, the manual I have showed what I was doing wrong. I was bringing it to TDC compression, but the points where closed, the manual says to advance the distributor until the points just start to open, did that and it fired right up.

I did notice that the tractor ran better a little better with NGK 3112 spark plugs than Autolite 437, same tune, same gap, roughly same amount of time doing the same job. Has anyone else seen this?
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top