8n low power with load

[RodTag]

Need some expert advise. I have the following.
8n front mount w/pentronix
The tractor starts right up, shows 40 lbs oil pressure, and sounds strong without a load.
When I run the brush hog it looses power when cutting grass that is not very high.
It ran fine on Sat but noticed the oil pressure went down to 25lbs. I parked it for a day and restarted with oil pressure back at 40lbs.
Any ideas on where to start looking?

 

[Ultradog MN]

Loss of power and oil presure are probably unrelated. Do you know the history of this engine?
25 psi at full power, hot engine is still in a good, safe zone.
Pertronix is generally pretty fail safe. Either it works and works Good or it doesn't work at all.
I would as a matter of course pull a plug and check your spark. But I suspect you have something going on with your carb.

 

[R Geiger]

I would pull all the plugs and take a look. you may have one or more fouled out. I have one cylinder that fouls plugs and the first indication I get is a loss of power when mowing. Runs pretty good on three cylinders as long as not mowing..

 

[Dell (WA)]

Rod.......Pertronix does NOT have a high reputation in the 4-nipple squarecoil application. Very voltage sensitive in the 6-volt positive ground application.

Ya gotts WEAK SPARKIES even with a good Pertronix. Your squarecan ignition coil has about 1-hr of run time and then it looses its spark-ability due to HEAT. The internal insulative tar MELTS. The ONLY cure is a NEW COIL.

It is NATURAL for HOT OIL to loose pressure and will re-pressure when COLD from overnite. ......Dell

 

[lha]

In addition to other helpful advice,might check timing order,1,2,4,3 starting from upper left[facing dist]CCW around the cap.---lha

 

[souNdguy]

ditto what the others said.. check fire order though it is likely correct if it runs good for a while.

check for fouled plugs.

tht drop from 40 - 25.. was that gradual while working it? if so indicates a normally worn engine.. no biggie. it's when you see a drastic drop that is a problem.

do you have a spare coil? if so.. next time it doe sthis swap coils.. if that fixes it, verify you are running the correct ballast resistor with the coil.

post back.

soundguy

 

[GB in MT.]

[b:ad4f1f1e76][i:ad4f1f1e76]
Rod;
You say: "The tractor starts right up, shows 40 lbs oil pressure, and sounds strong without a load.
When I run the brush hog it looses power when cutting grass that is not very high. "

What all the others say, MAY be the cause......OR,...it may be that the HOG blades are dull, and need to be sharpened....Or the gear lube in the gear box for the blade is low.
Also check the TPH sump for low hdrol. fluid!!!

Just a thought....Try running the "N" with out the PTO on, in high gear, up-hill, with the TPH up.
If still runs good that way....I would suspect something with the Brush Hog!!!????

Post results please!!

Gary :roll:
[/i:ad4f1f1e76][/b:ad4f1f1e76]

 

[JoePilot]

Lots of good advice. Also, check the secret fuel screen in the carb inlet elbow (very easy). It gets clogged and causes power loss and sputtering under load. Happened to me...

Joe

 

[RodTag]

Sorry I am just getting back to the forum. For some reason the form did not email me when responses were posted.

All these ideas are good. I will check them one by one this weekend. Thanks again guys for point me in directions.

 

[RodTag]

Sorry I am just getting back to the forum. For some reason the form did not email me when responses were posted.
All these ideas are good. I will check them one by one this weekend. Thanks again guys for point me in directions.

 

[RodTag]

well it seems the hog had low oil in the tank. added some and mowed for an hour without any problems. Thanks you guys for the great advise.