8n surge

[Brian70ss]

Hi, been a while since I posted. I got the 8n out for the first time this year. started on about the 5th crank. I was blading on level ground and the tractor kept surging. I was wondering if the governor needs rebuilt. I installed a new carb last year (repop of a marvel). If I am going up a hill with a real good load on the engine it does fine but driving around on level ground whether blading or not it surges. If I look I can see the linkage moving.I havent used the mower I have yet to see what it would do but I would assume with a load it would be ok. Thanks for the replies Brian

 

[souNdguy]

while it could be the governor.. ( too much preload or too much slack ).. I'd look at a fuel obstruction..


when surging.. does choke help it smooth out?

soundguy

 

[Brian70ss]

Forgot the golden rule
49 8n
front dist
6volt
governor off of newer with tach drive
should I go back to the other style governor.

 

[Dell (WA)]

Brian......surprizingly enuff, the LATER proofmeter governor is internally the same as yer original non-proofmeter governor.

And YES, the governor is causing yer surges in response to the DEMAND of the engine for power. ...but... its probably 'cuz yer engine is TOO-LEAN. try ENRICHING the down-pointing mainjet, 1/8-turn attta time CCW. then driver. .......Dell

 

[Bruce (VA)]

Like Soundguy said, check for fuel flow. Get a can & put it under the carb. Remove the bolt in the bottom of the carb; as long as the fuel is turned on, you should see gas flowing out of the carb. Let it run for at least 30 seconds. If it’s a dribble, or runs for 5 seconds & stops, or none at all, you have solved the problem: it’s fuel related. If gas flows well out of the carb & only stops when you turn it off at the sediment bowl, chances are very good it’s not a fuel flow problem.

Also, try using the choke when it surges to see what that does.

The model of the governor (proofmeter or not) doesn't make any difference.

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

 

[Brian70ss]

Yes choking it helps. It just seems to load up when choke is about half way out. maybe less.

 

[souNdguy]

it's likely too lean a mainjet ( could be crud in the needle ).. or a fuel obstruction.. could be tank vacume too.

post back after checking.

soundguy

 

[Brian70ss]

Wow, You guys are something else. I adjusted the mainjet and the problem went away. Had to adjust it about a half a turn in 1/8 turn adjustments. Thanks alot for the help Soundguy,Bruce,and Dell. Brian

 

[souNdguy]

good luck.

it may have been too lean for a while.. or it may have had some crud in there that broke free when adjsuting it.

as long as it is not puffing black smoke or stumbling on it self and put-putting from being too rich you are probably good to go.

soundguy