Marginal throttle response

[Priest]

1949 8N front mount, 12v converted Neg Ground. starts ok with the choke, as a couple of minutes go by less and less choke are needed until no choke. engine idles slow and ammeter reads 0 (not - or +) when rpm is raised ammeter reaches 8to10 positive charge. oil pressure is 35 as i'm running strait 40 weight for TX heat, it drops lower as engine/oil warms. !!!When I try to raise the RPM (clutch IN no engine load) I can only go one notch on the throttle control lever and then wait for the engine to catch up, if I go too fast (engine not warm enough) or try to go too far on the throttle the engine looses power and drops back to idle. and then I have to try slowly to raise the rpm again. This symptom started when I was using the brush hog to clear land and has just gotten worse over time. It started as a mere inconvenience when I hit thick brush to bring back the rpm's to start shredding again, now just the weight of the tractor is too much for the rpm drop. I checked the governor and one ball has a slight flat spot, the rest look good. Fuel runs well out from the carb bowl. Air cleaner checked and cleaned. spark is strong.
To surmise my throttle isn't controlling the engine rpm. HELP!

 

[Bruce(VA)]

You could have a mechanical throttle control problem or a governor problem.

A problem w/ the throttle plate on the dash or a linkage problem should be easy enough to detect by moving the throttle rod & making sure everything works as it should to the governor.

There are three ways to check to check the operation of the governor. Get the throttle lever at it's lowest point (engine ideling) Then, start tapping the throttle lever slowly open. How far does the throttle move before the engine speeds up? Lack of low speed throttle response (like about 1/3 of the throttle) is the classic symptom of a bad or out of adjustment governor. Next test, put it in gear at about 1/4 throttle, put your foot on both brakes & let the clutch out.
The engine should throttle up as the governor arm opens the throttle plate in the carb to compensate for the load on the engine. Next test, w/ the tractor running, pull on the rod going to the carb; does the governor pull back? If that does not work, get out the I&T FO4 manual & check out the 'adjusting governor' paragraph.
50 Tips

 

[HCooke]

You should be able to raise the RPMs by moving the
gov to carb rod by hand. (And the gav should fight
back) If not, then the problem is not in the gov. I
would suspect the power circuit in the carb is
clogged.

 

[Priest]

Thanks for the help guys. I have ordered new governor steel balls as I found some wear on them and I believe are contributing to the issues. I've also made some improvements to the settings on the Idle and Power needles on the carb. When I pull on the Carb to Gov rod, the Gov pulls back. My Next question: in the FO-4 shop manual, "The final adjustment of the main (Power) needle should be made with the engine running at governed speed under full load." I had the engine at full throttle with the attached brush hog running, is this what is meant by "Governed Speed Under Full Load"?? :?:

 

[GB in MT.]

(quoted from post at 11:09:01 07/22/12) Thanks for the help guys. I have ordered new governor steel balls as I found some wear on them and I believe are contributing to the issues. I've also made some improvements to the settings on the Idle and Power needles on the carb. When I pull on the Carb to Gov rod, the Gov pulls back. My Next question: in the FO-4 shop manual, "The final adjustment of the main (Power) needle should be made with the engine running at governed speed under full load." I had the engine at full throttle with the attached brush hog running, is this what is meant by "Governed Speed Under Full Load"?? :?:

b:251205542a][i:251205542a]
Priest;
Try setting up your carb with these instructions. AND, if you do not have a "Proof meter", you will have to do it by ear, for smoothest/ fastest, RPM's>

Print this out, and follow the instrctions.:

AND, as you say the Gov. balls are worn, by all means, replace them!!!
Gov. has to work right, so it can tell the carb what you want it to do, power wise!!!
I find that you can usually set the Fuel "Power Needle" to, 2 full turns out and not have to touch it for final setting.

Gary [/i:251205542a][/b:251205542a]