OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines Briggs and Stratton 12hp governor linkage setup

Hi all

I have a 12 hp Briggs that has been rebuilt and have run the engine but the throttle and linkages don't feel right. I wanted to check before I spread the engine out on my driveway (in a bad way).

Model no 252707-0026-01-7905

Please see pictures

The main issue is that at full throttle there is bearly enough spring tension to open the butterfly. When you move to the choke position (slow position) the spring gets in the way and forces the throttle butterfly shut.

The throttle linkage is not off this machine, are there any major differences that could be at play, linkage length for example?

The governor touches the oil slinger at full throttle.

I can find a few threads on this same issue however they are for the rack and pinion set up.

Cheers

Mick

Hi Mick, here is the Illustrated Parts List for your engine:
http://bsintek.basco.com/BriggsDocumentDisplay/Z6lttJVJ1DajI.pdf
Here is the Operator's Manual:
http://bsintek.basco.com/BriggsDocumentDisplay/msoBGL-K_ny7tH217FzoPu.pdf

You didn't post the Code, so we don't know when it was manufactured. However if you look at Page 7 of 17 in the IPL, you can see what the parts of your governor mechanism are supposed to look like. In the Operator's Manual it is clearly a rack and pinion unit (page 7 of 14).

I think the solution to your problem is to get the correct rack and pinion parts from a wrecked engine. What you are attempting would require a long development job to get an inferior result. In my opinion it does not make sense to make a silk purse into a sow's ear.

Grumpy,

Sorry missed the last two numbers 790531 so built in 1979.

I moved the spring to the notch in the leaver and the tension profile is much better see attached picture

Ran the engine, runs steady and revs up nicely. I need to check the high idle speed with a tacho to make sure it is set up correctly.

In th e mean time I'll look for the rack and pinion style control box

Cheers

Mick

Thanks for the update, Mick. While it can be worthwhile spending time on manufacture and development of a part for a rare antique or vintage engine, we only do it because there is no other way to get the engine working, and it is a special engine, the preservation of which is important. As you know, your engine is useful but not rare or special, and furthermore, second-hand parts for it should not be difficult to get at reasonable prices.

Like many of us, I have in the past spent ridiculous amounts of time trying to avoid paying less than $5 for a part (usually a car part) I could have bought from a wrecker. My home-made parts were sometimes less reliable than the real thing, and I was always worried that they might be, even if they weren't in practice. In my opinion there are much better ways for you to invest your time - but it is your time, and your choice.

Hi all

Whilst having a look at the part list I found a part that I have got but don't remember removing. Also I can't see where it fits.
Part 760 in the image is a counter weight spacer.

Can anyone let me know where it is supposed to go?

FYI the engine is running

Cheers

Mick