# Adding a throttle to a Briggs engine



## skutflut (Oct 16, 2015)

I have a Craftsman unit, with a B&S 20m114-0937-E1 , 1350 series engine. I want to add a throttle control to the unit.

The reason is not to blow snow at lower speed, but to let the unit run at a slow speed during warm up, and after blowing, while the snow is melting off the engine a bit, but to be a bit quieter about it.

Is this possible since this engine has a governor on it, which lives in the same space as the throttle control would go. I do not want to sacrifice the governor since it has worked well so far, just want to be able to have a quieter and less engine stress start up and shut down.


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## motorhead64 (Dec 15, 2013)

Hi Scutflut,
What you are contemplating is not really practical for your engine's design. MH


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## Normex (Feb 21, 2014)

This is what I roughly envision to convert a full speed only to adding a second setting of idle which is not to be used for operating the snow blower but for warm up and a cool down period to clean the blower of snow.
I am open to suggestions if this is feasible as envisioned.


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## Zavie (Sep 23, 2014)

I looked into this once. Chances are the parts you need will be found used on ebay sooner or later. Get to be friends with a small engine guy near you. B&S adds and subtracts throttle, on off switch, etc on their engines based on end user needs so if you can obtain the correct parts you are golden.


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## skutflut (Oct 16, 2015)

Zavie said:


> I looked into this once. Chances are the parts you need will be found used on ebay sooner or later. Get to be friends with a small engine guy near you. B&S adds and subtracts throttle, on off switch, etc on their engines based on end user needs so if you can obtain the correct parts you are golden.



After looking through various parts sites, it appears that B&S has a throttle assembly that fits this basic version of the engine. I have not been able to find any detail drawings or a parts listing showing how it would connect to the carb, which now has control rods to the governor, and the governor bracket assembly with the multi hole pattern to adjust spring tension.

Do all the B&S engines of this design have governors or is it either governor, or throttle, not both? I have run across a similar engine that does have throttle control, but the owner wouldn't let me take the gas tank off to take pictures.


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## ELaw (Feb 4, 2015)

Every lawnmower and snowblower engine I've ever seen has a governor. "Governor" being loosely defined as a spring that pulls the throttle plate in the carb open, and some engine-speed-dependent mechanism that creates a force that tends to closes the throttle plate. The balance between the spring force and the force from that mechanism determines the engine's speed.

Engines with no user-adjustable "throttle" simply have the spring attached to a fixed point so its force is a constant pre-set value. Engines with a throttle have some sort of adjustment mechanism so the spring force can be varied. Setting the throttle to "high" or "fast" increases the spring tension so the governor has to provide more force to close the throttle plate, and thus the engine runs faster. When you set the throttle to "low" or "slow" the spring tension is reduced and the engine runs slower.

Which is a very wordy way of saying that if you can find a setup that attaches to your engine, but provides a way of adjusting the force of the governor spring, you should be in good shape.

As a side note, I think starting an engine at wide-open throttle and having it go to full speed the moment it catches, is a great way to let your engine know that you hate it and want it to fail. Adding an adjustable throttle so that it can run at a low speed upon startup is IMHO very valuable.


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## skutflut (Oct 16, 2015)

As a side note, I think starting an engine at wide-open throttle and having it go to full speed the moment it catches, is a great way to let your engine know that you hate it and want it to fail. Adding an adjustable throttle so that it can run at a low speed upon startup is IMHO very valuable.[/QUOTE]

I tend to agree with you on the fast start on a cold engine. In my years of using a snowblower, I have noticed that without fail, on the days I need this machine, it's always COLD and sometimes, REALLLLLY cold.

This one probably has less than 100 hours on it, but it is the seventh winter, and I think it deserves to be woken up gently and have a few minutes to get used to being awake, just like I need in ANY weather.


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## scrappy (Dec 7, 2014)

I'm wondering if the non throttle carbs have idle jets and a way to adjust idle speed.

Might have to change the carb too.


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## ELaw (Feb 4, 2015)

That's a good point! Although even at 3600 RPM, under no load the engine is typically operating with the throttle plate pretty close to the idle position.

I'd think in the worst case you could get a lower governed RPM and improve things a bit.


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## skutflut (Oct 16, 2015)

scrappy said:


> I'm wondering if the non throttle carbs have idle jets and a way to adjust idle speed.
> 
> Might have to change the carb too.


According to Repairclinic.com, the part number for the carb for my engine, 20m114-0937-e1 and a 20m114-1358-e2 engine (which has a throttle control) is the same. I'm guessing it should have an idle jet, just not being used much. Also, the Briggs general repair manual identifies one type of carb for all the 200000 series engines.


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## scrappy (Dec 7, 2014)

skutflut said:


> According to Repairclinic.com, the part number for the carb for my engine, 20m114-0937-e1 and a 20m114-1358-e2 engine (which has a throttle control) is the same. I'm guessing it should have an idle jet, just not being used much. Also, the Briggs general repair manual identifies one type of carb for all the 200000 series engines.


sounds good... it's not rocket science.

If you have to fab linkage, bicycle spokes preferably SS work great.


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## skutflut (Oct 16, 2015)

skutflut said:


> I have a Craftsman unit, with a B&S 20m114-0937-E1 , 1350 series engine. I want to add a throttle control to the unit.
> 
> The reason is not to blow snow at lower speed, but to let the unit run at a slow speed during warm up, and after blowing, while the snow is melting off the engine a bit, but to be a bit quieter about it.
> 
> Is this possible since this engine has a governor on it, which lives in the same space as the throttle control would go. I do not want to sacrifice the governor since it has worked well so far, just want to be able to have a quieter and less engine stress start up and shut down.


*STOP THE PRESSES
*
I found what I hope is the right throttle plate for my briggs engine on Ebay. It has the throttle control lever, and secondary bracket to basically remove the tension from the governor spring. Plate looks the same as the one I have, but with the extra bits installed. Mine is much cleaner than this used one, but once i put the tank back on, nobody will see it anyway. Guess I will find out if this is going to work in mid November when the thing is supposed to get here.

I shall try and photo document the transition and hopefully, the end result. 

Now I just have to get the red knob for the throttle lever to make it look pretty


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## skutflut (Oct 16, 2015)

ELaw said:


> That's a good point! Although even at 3600 RPM, under no load the engine is typically operating with the throttle plate pretty close to the idle position.
> 
> I'd think in the worst case you could get a lower governed RPM and improve things a bit.


While probing around getting photos of my throttle plate for comparison to ebay photos, I did find an idle speed adjustment screw on the carb. The governor holds the carb wide open when the engine is off, and I assume starts governing the speed at full speed when its running. While figuring out the governor operation, slacking the spring closes the carb butterfly down to where it hits the idle adjustment screw. Guess that might need some tweaking since it has never been used for its purpose, and I don't expect that briggs mfg testing sets things that are not going to get used on the engine.


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## Normex (Feb 21, 2014)

scrappy said:


> If you have to fab linkage, bicycle spokes preferably SS work great.


 I just finished fabing a linkage for pulling the governor to idle with the bicycle spoke. Those are high tensile and one has to heat them red to bend them. I know heating them probably loose some strength but it still fit the purpose nicely.


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## Zavie (Sep 23, 2014)

Pretty sure the ebay parts will work out for you just fine. When I was looking to add a throttle to mine I came to the same place you are at. I decided not to go an add the parts because mine is still under warranty. I'm also going a different route with my machine. After warranty if I'm sticking with this machine and not going to a Husqvarna hydro unit I'll most likely re-power current machine to a larger engine.


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## skutflut (Oct 16, 2015)

Zavie said:


> Pretty sure the ebay parts will work out for you just fine. When I was looking to add a throttle to mine I came to the same place you are at. I decided not to go an add the parts because mine is still under warranty. I'm also going a different route with my machine. After warranty if I'm sticking with this machine and not going to a Husqvarna hydro unit I'll most likely re-power current machine to a larger engine.


My warranty is long since over. I agree you don't want to mess with things under warranty, even if what breaks is nothing to do with what you did.


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## skutflut (Oct 16, 2015)

skutflut said:


> *STOP THE PRESSES
> *
> I found what I hope is the right throttle plate for my briggs engine on Ebay. It has the throttle control lever, and secondary bracket to basically remove the tension from the governor spring. Plate looks the same as the one I have, but with the extra bits installed. Mine is much cleaner than this used one, but once i put the tank back on, nobody will see it anyway. Guess I will find out if this is going to work in mid November when the thing is supposed to get here.
> 
> ...


Throttle plate finally arrived after seeing more of the USA and Canada than I have, but thats another story. 

I installed the new throttle plate, hooked up the governor spring to the movable lever, and works like a charm. I have attached a photo of the new (in 2001) throttle plate with the throttle lever and intermediate pivoting governor spring bracket in case anybody else is looking for one. 

They seem to come in many flavours with an all purpose base stamping, then various bits riveted on depending on the engine model. Saw one that had an electrical contact on it so that the throttle would also function as a kill switch , but that one had the wrong intermediate bracket for my governor arrangement. I guess Briggs likes to get their money's worth out of every part. 

The original had a fixed mounting post for the governor spring, while this one is movable. The new one has the same fixed post on it, but it is under the pivoting bracket and was never "Bent" up from the base stamping. Pivoting bracket is riveted on to the base stamping and covers the fixed, unbent anchor point. For anybody who might ask, YES, i did clean the thing up before installing it. This is the photo from Ebay, 

Now, all I need is an excuse to warm it up :icon-hgtg:


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## BobCat520 (Oct 24, 2013)

skutflut
I think that you made a wise decision to go with an adjustable throttle. As you mention, starting up an engine in the freezing cold at full bore isn't going to make it's life span any longer. I have a squeeze handle, something like a bicycle brake lever on the handlebar on my BobCat I let it warm up at idle speed and when operating it 
I let it go to idle when switching speeds, or going into reverse. I also like to be able to let it idle while I do some close in shoveling..nice to be able avoid multiple re-starts.


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## skutflut (Oct 16, 2015)

BobCat520 said:


> skutflut
> I think that you made a wise decision to go with an adjustable throttle. As you mention, starting up an engine in the freezing cold at full bore isn't going to make it's life span any longer. I have a squeeze handle, something like a bicycle brake lever on the handlebar on my BobCat I let it warm up at idle speed and when operating it
> I let it go to idle when switching speeds, or going into reverse. I also like to be able to let it idle while I do some close in shoveling..nice to be able avoid multiple re-starts.



Im not fussy about shutting down and restarting either. I think my engine has an issue with the auto compression release. It starts ok with the electric starter, but pulling that thing with the recoil is a bear. The machine is more likely to move across the floor than the engine turning. Tried adjusting the valves, and it seems to have improved a bit, but still a real effort to get that thing past the compression stroke. Here's hoping the electric start never fails, and all starting is done beside the garage where the ac outlet is. Maybe the next snowblower I buy, if I live that long, will look more like this


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## Skidoo7128 (Feb 2, 2020)

Skutflut- did you ever find out what the part number what for that new throttle plate? Also how has it worked out for you? Thx


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## skutflut (Oct 16, 2015)

Skidoo7128 said:


> Skutflut- did you ever find out what the part number what for that new throttle plate? Also how has it worked out for you? Thx


I do not know what the part number is, there are several different throttle plates available, each of them has several different versions from what I found while doing my research. The version you need depends on the engine model you have, but if you take a photo of the plate you have, its pretty easy to compare it with photos on Ebay, which is what I did. 

There are people selling lots of parts on Ebay for all manner of small engines. They all appear to have come from used engines, but in my case, the part is pretty much bullet proof and I was not concerned about it being worn out of defective, it's just not subject to failure.

The basic plate contains no levers or other means of adjusting the throttle. Another version is populated with the throttle handle, and that lever which serves to add or reduce tension on the governor spring which increases or reduces the engine speed. Yet another version has the throttle mechanism, plus a switch mechanism which is actuated by the throttle lever and kills the engine when the throttle is moved completely to the slow position.

The modification worked out perfectly. I removed the governor arm from its spindle, unbolted the original throttle plate, installed the Ebay purchased version with the throttle adjustment parts installed, reattached the governor arm to the spindle, checked that it was still calibrated the same as when removed, put it all back together and tested.


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## Wilbour (Nov 2, 2021)

Just assembled a new Snowblower by Briggs and Stratton yesterday (took way longer than it should have for various reasons).

It's an 1150 Snow series 250cc. It gave me some trouble on startup and when I reread the instructions it clearly recommended the throttle be in the fast position.

After I adjusted it as stated in the manual it fired up. I'm not entirely sure what the point is of this option given that fellow posters are recommending it not be on fast before warming up.

Perhaps after it gains momentum one should move the leaver to slow and let it idle for a minute or two?


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## Oneacer (Jan 3, 2011)

All my equipment is put in the Fast position for startup.


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