Explain this Tilliotson HS govenor to me

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Modifiedmark

Modifiedmark

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Can someone explain why and how this govenor works on a HS carb?

For example when I rebuilt my Dayton/Poulan 245 I put a kit in the carb. Saw started right up and ran fine untill I tried to set the H screw on it. The saw was very rich but I could not get it to clear out and rev up till the H screw was turned almost all the way in on it.

I put the kit in another carb I had and all was fine. I had had he same problem with another HS on a 306A.

Now today after kitting the HS on this Wright blade saw, this carb is doing the same thing! Thing is very rich and wont clean out till the H screw is turn into about 1/4 turn out then it dies. With the screw 1 turn out it just wont hit max rpm and just kinda surges and smokes.

This governor is the brass valve screwed in the side of the carb right? How does it work? Can I replace it or bypass it or what.

I'm all ears boys and girls. :cheers:
 
Is that valve the one with a ball bearing inside?Can it be dis-assembled and cleaned?
 
Modifiedmark said:
Can someone explain why and how this govenor works on a HS carb?

For example when I rebuilt my Dayton/Poulan 245 I put a kit in the carb. Saw started right up and ran fine untill I tried to set the H screw on it. The saw was very rich but I could not get it to clear out and rev up till the H screw was turned almost all the way in on it.

I put the kit in another carb I had and all was fine. I had had he same problem with another HS on a 306A.

Now today after kitting the HS on this Wright blade saw, this carb is doing the same thing! Thing is very rich and wont clean out till the H screw is turn into about 1/4 turn out then it dies. With the screw 1 turn out it just wont hit max rpm and just kinda surges and smokes.

This governor is the brass valve screwed in the side of the carb right? How does it work? Can I replace it or bypass it or what.

I'm all ears boys and girls. :cheers:
Click to expand...

Mark, I think that you just answered my problem! I just rebuilt the carb on a 245A that I just got and it is acting just like you described. I can't get it to adjust to my opinion of how it should run. So how can you tell the difference in the carbs that have the governer and the ones that don't?:confused: I have about 10-12 of these carbs and don't want to waste my time on another carb with a governer.
 
The Dolmar 133 uses an HS carb with the "governor check valve".It shows a gasket underneath and has a footnote to secure the valve with "glue".It does not specify what the "glue" should be.
Maybe nail polish would seal it in place.
 
HimWill said:
Is that valve the one with a ball bearing inside?Can it be dis-assembled and cleaned?
Click to expand...

I don't see how it can be taken apart, and it seems very clean. You can push on the ball inside and it moves very easy. Almost too easy it seems. Passage in the carb is clean also.
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From the 2100 workshop manual.

"Speed governor

The purpose of the governor is to limit the engine
speed in order to protect vital parts like the crankshaft
and ignition system from excessive stresses.
We therefore advise most strongly against any interference
designed to render it inoperative. When the
saw IS run under no-load conditions, the engine
speed IS limited to 10,500 r/min as the governor
comes into operation.

The steel ball and spring in the governor are so devised
that vibrations in the carburettor at a certain
engine speed cause the steel ball to open the fuel
outlet. An excessively rich mixture IS then obtained
and the engine begins to four-stroke, the speed
drops and the vibrations decrease. The steel ball
then closes the outlet, the engine speed increase
and the process IS repeated.

Removal of speed governor

Remove the screw for the choke flap. Pull out the
flap approx. 7 mm and push out the choke shaft
approx 5 mm. Remove the speed governor with a
suitable screw driver."
 
Urbicide said:
From the 2100 workshop manual.

"Speed governor

The purpose of the governor is to limit the engine
speed in order to protect vital parts like the crankshaft
and ignition system from excessive stresses.
We therefore advise most strongly against any interference
designed to render it inoperative. When the
saw IS run under no-load conditions, the engine
speed IS limited to 10,500 r/min as the governor
comes into operation.

The steel ball and spring in the governor are so devised
that vibrations in the carburettor at a certain
engine speed cause the steel ball to open the fuel
outlet. An excessively rich mixture IS then obtained
and the engine begins to four-stroke, the speed
drops and the vibrations decrease. The steel ball
then closes the outlet, the engine speed increase
and the process IS repeated.

Removal of speed governor

Remove the screw for the choke flap. Pull out the
flap approx. 7 mm and push out the choke shaft
approx 5 mm. Remove the speed governor with a
suitable screw driver."
Click to expand...

Does yours have a spring in it, Mark?
 
Thanks Vince, that makes sense now that it is explained. It also makes what I was thinking seem right, that it is rich becase that valve must be malfuntioning.

I was over at the Tillitson site and downloaded the parts manual for that HS carb, and it shows a part # for that replacment govenor. Now where to get one?

I wonder if it could be plugged off to try it out that way?
 
Modifiedmark said:
Thanks Vince, that makes sense now that it is explained. It also makes what I was thinking seem right, that it is rich becase that valve must be malfuntioning.

I was over at the Tillitson site and downloaded the parts manual for that HS carb, and it shows a part # for that replacment govenor. Now where to get one?

I wonder if it could be plugged off to try it out that way?
Click to expand...

I'd flow a little brass in the end of the governor, and wind it in there. You're not going to run that thing enough to blow it up anyway.
 
I can give you the part numbers for the HS Dolmar uses.What carb number is it anyway?
 
Modifiedmark said:
It's for a 59A and the 58B. I think I found the part #'s for it from the Tilliotson parts list for the HS

How about just putting a flat piece of gasket under it to try it?
Click to expand...

Probably less drastic than my idea. You'll never know if you don't give it a try. How come there is always someone trying to keep us from getting ALL the power out of our saws. I didn't realize much of this went on before the EPA, but I guess it was a reliability issue then.
 
I think I read in a partner manual turn H in untill it won,t rev then richen 1/4 turn. Unless the saw is ported alot leaving the gov won't matter much in the cut.
 
ms460woodchuck said:
Mark, I think that you just answered my problem! I just rebuilt the carb on a 245A that I just got and it is acting just like you described. I can't get it to adjust to my opinion of how it should run. So how can you tell the difference in the carbs that have the governer and the ones that don't?:confused: I have about 10-12 of these carbs and don't want to waste my time on another carb with a governer.
Click to expand...

I think all of the Poulan HS carbs had them, but I can't be certain.
 

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