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Briggs and stratton 11hp governor issue
Hello fellow experts. I am an ASE certified technician and can fix just about anything on a car......a small engine however.....so somple that it's complicated to me.
Here is what I have going on here. I have a Powerback 6000 watt generator made by DeVilbiss Air company, it has an 11hp Briggs and Stratton Industrial plus engine, model # XXXXX type 1162e1. Bought this several years ago, ran for a few hours and then put in storage, stupid me should have known better.....I didn't drain fuel or prep for storage. I pulled it back out this week and changed the fuel, the engine would run but had issues. First I found that the throttle linkage from the governor to the carb would not move, after a few good tugs it broke loose and now operates. Engine will start and run however it would not stay running unless you keep it in full choke mode, stalls as if you hit the cutoff switch if you place it in run mode. I removed the carb and cleaned it out/soaked in cleaner and cleaned out all the ports/float/bowl/etc.....Reassembled and now the engine runs GREAT! Starts first pull in choke and runs great in "run" position, however here is the problem- the governor will not operate????? The engine screams to maximum RPM and the muffler glows, this engine has a mechanical governor that runs to a shaft inside the engine, not sure how this is supposed to work but the shaft does not move, I can manually move the linkage back and forth to regulate engine speed but the governor will not function.
Can you explain how this governor works and what I need to look for? If I pull the linkage off the rod I can spin the rod about 3/4 turn either direction and get a "click" noise when it stops, is this rod supposed to spin back and forth in coordination to engine speed? How do I properly position it? Is it possible that a spring or something came apart inside the engine or is this mechanical and out of adjustment?
Ahhh - the 'no-govenor' problem! Assumng you don't want to build a go-kart with the engine - proceed as follows ;-
Loosen the clamp bolt so the govenor arm is free on the shaft.
Rotate the shaft - in the direction that would tend to OPEN the throttle - as far as possible
Push the govenor arm against spring pressure so the throttle is wide open.
Tighten the clamp.
Having said all that, the govenor should have been set up correctly when you pulled it out of storage. I suspect what has happened is the govenor spool (which slides on the camshaft under the influance of a pair of flyweights) has stuck in position due to being left for so long. This is unusual, but not unheard of.
This has happened to a couple of engines I've had in the shop over the years. On one occasion I freed it up with a sharp tap on the engine casing over the camshaft bearing. Problem is you need to do it with the engine running, and you need to remove the cowling. If that doesn't work, the engine needs to come apart for investigation.
Let me know the model and type number off the engine - I should be able to find an exploded diagram.
Govenor function ;-
On the camshaft is an assembly consisting of a set of small weights. As engine speed increases, these weights fly outwards. This motion is transferred to a sliding 'flange' on the camshaft upon which is resting a lever attached to the end of govenor shaft that sticks out of the side of the engine. To the other end of this is attached the govenor arm. This arm is attached to the carb throttle, and is spring-loaded to the throttle open position. When the engine speed increases, the govenor is supposed to move to overcome the tension on the govenor spring, and close the throttle. The point at which the force generated by the govenor mechanism equals the force generated by the spring sets the engine speed. More spring tension = more speed.
OK - sorry - re read the question got type numbers. Found exploded diagram on line at http://www.briggsandstratton.com/pdf/illustrated_parts_list/100/MS0603.pdf. This should give you all the info you need to pull it apart.
Thanks for letting me know - rubber mallets have been known to fix almost anything!
Muffler - you can either fit the largest standard Briggs muffler that will physically fit in the space available, or fabricate something. All you need is a metal box - the larger the volume and the stiffer the walls the better. Just make sure the exit is about the same cross-sectional area as the exit of the existing muffler or header pipe. If it doesn't need to be portable, it's not a problem. I have a 12HP Briggs on a generator that is almost silent - the mechanical noise from the engine is MUCH louder than the exhaust.