Is it safe to run Briggs & Stratton 5 hp engine without governor?

[kinwin]

I recently got hold of a very hold and rusted chipper/shredder. It's a craftsman model# 247.797851, I believe from 1990.
Previous owner said it hasn't been used for years, but it did run fine before that. I cleaned the carburetor, replaced the spark plug and lo and behold the engine fired up.
However, this is when I noticed the engine has no governor. In the attached pictures, you can see where the governor rod is supposed to be, there is simply a bolt.
I figured the previous owner removed the governor on purpose and ran the engine by manually adjusting the throttle.
My only worry is, how do I know I'm not running at too high rpm? Is there an easy way to tell you are running at slow enough rpm to be safe?

 

[bertsmobile1]

No
3,500 rpm good
4,000 rpm better
5,000 rpm BANG
That is why the DPO put that bolt in there to restrict the amount of throttle opening .

 

[kinwin]

Thanks for the fast reply. Now I know I should not be running higher than 4k rpm.
Onto he next problem, how do I measure the rpm? I guess a newbie like me can't tell the rpm just by listening to the sound of the engine. I'm eyeing some cheap tachometers on Amazon (they sell for < $13). You wrap some wire around the spark plug, and the meter is supposed to tell you the rpm. Is that something I should get, just to get piece of mind that the previous owner calibrated the throttle correctly?

 

[bertsmobile1]

That bodge should be removed and the original system restored or the shredder will not work properly
Without the governor it will die under heavy load so would not be much use other than to chop up dried leaves in Autumn prior to composting them.
Just by the spark plug there should be some numbers stamped into the blower housing.
Please post them so we can determine which governor was fitted to advise you how to proceed .

 

[Hammermechanicman]

If the original wilbur who hacked it up took out the govenor gear then the engine will rev to 5k and not blow but will wear the big end of the con rod prematurely. If the govenor gear is still in the engine then around 5k the plastic gear lets go and the metal weights fly around in the engine and may get in the cam/crank gears. You are probably missing a bunch of parts to put back to stock.

 

[kinwin]

Alright, attached are pictures of the blower housing. I also included the model number of the chipper found at the bottom plate.
Any advise is greatly appreciated.

 

[bertsmobile1]

A bit hard to read but as it is 5 Hp, if that blower housing is the original one you have a 130000 series engine made in 1990 .
To me it looks like 130212 3250-01.
If that is right both the owners manual & parts manual can be downloaded from the Briggs web page .
The IPL shows a cam shaft mechanical governor which I will guess is broken resulting in the bolt in the throttle control work around .
Check this by finding the governor rod where it pokes out of the crankcase .
start the engine & hold onto the governor rod.
It should try to rotate as the engine speed goes up & down
If it does then get all of the missing linkages and hook it up
If it does not then you need a rethink as repairing it means a full engine strip .
Check the carb is the same as the IPL shows because he could have also fitted an incorrect carb which did not link up to the original governor easily

 

[kinwin]

Yes, I think you are absolutely correct, this is the 130212 3250-01 engine. Based on the diagram in the manual, unfortunately, the previous owner removed the governor rod completely, as where it should poke out, now is only a bolt. See the attached pictures of the relevant pages in the manual compared to the picture of the crankcase. I have marked in the pictures the relevant parts.

No, I don't want to do a complete engine strip, I'm fine running it as-is and use it as a light leaf shredder.

 

[7394]

That's how I blew up my B&S 5hp on my Go-cart as a young kid.. My Dad was not impressed..

 

[bertsmobile1]

Well it looks like the governor gear # 391737 is still available and around $ 40 and the control arm # 490374 is $ 5
If the rest is in good order, those + a gasket set make it a very cheap shredder