'51 8n

[Ric0126]

Ok, I guess I'm ready to be taken to the wood shed again. But I'm just sayin. Here's what I've done to Dad's tractor that has been sitting. Pulled the carb down twice and cleaned very well. Repalced plugs, wires, coil, condensor, cap and rotor cleaned and set points. Checked timing mark (both places on the flywheel) and set timing for firing order (1,2,4,3) assuming 1 is in front and 4 near the seat. 1st positioned with 1 tdc at about 2:00 towards front of engine. Nothing. 2nd position with 1 tdc near 9:00 rear of engine. Backfires will not start. Did a compression test and the results were 1&4 over 50psi 2&3 between 25 n 30psi dry. Retested after wetting the rings and got 50psi all cylinders. I have fire at the switch, coil, points and plugs.




Do I have the cylinder order correct.

 

[mhb@ufe]

Yes you have the cylinder order correct but your compression is way low. Should be 90 psi minimum. I"ve seen them running with compression as low as 70 psi but I would not expect it to run with the numbers you"ve got.

Mark
Union Farm Equipment Inc

 

[old]

Sounds like it needs a week or an ATF treatment. 50PSI is not enough to get an engine to run well if at all. 90PSI is the min. needed for the 8N. I would fill the cylinders with ATF and let it sit at least a week. Also sounds like you have the firing order 180 out since it is back firing and you have it firing on exhaust stroke instead of compression

 

[lha]

As said earlier,I would put a pretty good bit of atf in each cylinder[too much will not hurt]and let it sit as long as you can stand it.I took mine apart mine at start of winter to fix carb &dist.and when I did that I put atf in cylinders,loosely put spark plugs back in.When I put back together,it ran great.---lha