300 RC won't reach rated rpm.

[primerk5]

Kinda at a loss at this point. I've read all kinds of posts on here about Us and 300s and 300 utilities trying to solve this but no joy so far.

Very recent engine overall and we noticed that it really wasn't getting up to the higher rpm to bring the PTO up to 540. I'm getting about 500 RPM on the PTO at wide open throttle and like 1600 to 1700 RPM on the tach. The governor looks really good inside and I don't see any worn parts. There isn't any wear in my linkage either. I replaced the spring thinking that potentially it was weak even though it looked perfect and that changed absolutely nothing. I checked to be sure that the governor was correctly connected or splined into the carburetor and it is. I have full range of movement of the carburetor butterfly. I would say that the spring seems a little loose when in the idle position but the holes don't appear to be worn that it sits in. They seem to be a bit oversized maybe 3/16 to 1/4 in diameter give or take. But they look like they were meant to be that.

I readjusted with not a lot of change but nonetheless the linkage on top of the governor that connects to the carburetor. I've backed the high speed stop completely off To be sure it's not stopping the throttle movement.

I'm able to achieve a fast RPM by disconnecting the throttle lever link that attaches to the governor and pulling it by hand and speeding it up but I'm pretty sure I have to put a lot to get it to pull the RPM up. Probably more than an inch past it's position when it is hooked up. When you do this though the engine surges high and then pulls it down and then high again and pulls it down so it doesn't stay at a consistent RPM when you pulled it that hard. It may have something to do with the rod being pulled and since you're holding it by your hand there is some movement.

I've seen a couple posts on this subject and some people solve the issue by the spring replacement which didn't work for me. One guy even cut down the rod but I'm afraid that I will lose my idle ability if I shorten that and I feel like it should work like this as it was intended. I'm pretty sure these are all original parts. It's almost like I don't have enough range in the throttle lever to pull the governor to the higher rpm.

I'm setting this stuff based on the it manual and owners.manual. any other ideas about what might be going on would be great.

Thanks

 

[Janicholson]

The linkage from the hand lever by the steering wheel to the governor, must pull the governor arm (on the back side) all the
way to the stop. The high idle stop will then adjust the max RPM. There are several linkage components that get worn in the
path from the hand lever to that governor lever, and adjustment potential. Even the rod that goes from the lever to the top
of the engine can get a twist in it. Jim

 

[primerk5]

I've had all that apart. All the connections in that linkage are in very good condition. There is little to no wear in anything that I see.

 

[fastfarmall]

Interesting Jim, i got a 450 LP, doesn't run fast enough either. Thanks for your input on differant things !!

 

[D Slater]

Picture of F model inside. Vertical rod should be adjusted first so butterfly shaft just rests or just missus the stop in carburetor. When little lever on front end of throttle shaft and tube to carburetor is full up is the stop position for butterfly shaft. Rocker shaft the vertical rod hooks to has needle bearings that pivot on cross shaft. Those, bearings, sleeve and thrust washer that puts pressure on the weights should operate smooth. Wear in spring holes not critical when at full throttle. Not running if you pull the lever on back of governor to stop, bottom bolt with throttle rod unhooked all you should feel is spring tension if no binding anywhere. If everything is okay the high speed stop should bring the RPM up unless the spring is weak. When you hand held it if it over speed the governor would try to slow it down and that could cause the surge. If full delivery is off a little that could also. Then once in a while getting a surge out takes some tinkering. More so on a sensitive one. Hit the wrong picture number first.

 

[D Slater]

Correction no spring pressure on linkage with engine stopped unless after weights close.

 

[Janicholson]

It must pull the lever on the back of the governor all the way to its stop. If not it is still wrong. See the part about
twist in the rod from the steering wheel to the engine!! Jim

 

[D Slater]

Should not have answered any question asked. Old timers done set in. For some reason I thought you were asking about a utility. Feel dumb after seeing you stated F model. Transfer what I said about pulling lever on backside of governor housing to push down instead of back and pull up for idle.