# Briggs throttle plate always wide open



## dmm26 (Oct 29, 2017)

Hey all,

So I have a craftsman 2 stage with a Briggs motor.
I've never run it before but it wouldn't start, cleaned the carb and it fired up 1st pull. 

Problem when it fires up is that it over revs and it seems as though the throttle plate is wide open no matter what position the throttle selector is in.

I took it all apart and can see that the governor linkage from the carb to the throttle selector doesn't seem to ever close the throttle plate.
I can't see that there's anything missing or malfunctioning.

Any ideas?

Thanks


----------



## leonz (Dec 12, 2014)

Try using some PB Blaster or Fluid Film to loosen up the linkage and let it sit for a day after soaking it and then try it again.

The other issue may just be that you have a bad fuel line that will cause it to surge and or it has a lot of dirt in the fuel tank and fuel line and you need a fuel filter.


----------



## 10953 (Sep 4, 2017)

governor and it's proper linkage adjustment needs to be addressed . there are links in sections in here for shop information on how to properly adjust it, 
example is if the spring is weak or in the wrong hole it will over rev. if the arm is not set to the governor by the book,it will over rev. that NO amount of lubricant will address wrongly done repairs,


----------



## dmm26 (Oct 29, 2017)

Thanks for the replies. 

I'll try the PB Blaster and see. The guy I got it from said it ran fine last year but just wouldn't start now.
It doesn't appear that there has been anything done to the governor system, it's almost like the the linkage is working backwards if that makes sense.

I'll post a video of what i'm seeing and it'll be easier for everyone else.


----------



## Jackmels (Feb 18, 2013)

The Butterfly itself may be Frozen. +1 on the PB Blaster to free things up.


----------



## dmm26 (Oct 29, 2017)




----------



## drmerdp (Feb 9, 2014)

The throttle lever doesn’t have a direct effect on the throttle plate. With the engine off the throttle plate should be wide open. As rpms climb the governor will try to close the throttle plate. The speed control lever has a spring that resists the governors attemp to close the plate. 

It looks like everything is hooked up properly. Does the throttle plate move freely? It’s possible that the governor arm is incorrectly position on the governor shaft. Do you have a tach to verify RPMs


----------



## dmm26 (Oct 29, 2017)

Throttle plate moves freely.
I don't have a tach.

I'll have to look at the arm then. It looks like everything is in place.

Thanks for the reply.


----------



## tdipaul (Jul 11, 2015)

_it ran fine last year but just wouldn't start now_

Guys who say this cannot be trusted. Anything is possible


----------



## 10953 (Sep 4, 2017)

tdipaul said:


> _it ran fine last year but just wouldn't start now_
> 
> Guys who say this cannot be trusted. Anything is possible


 it ran last year,but not saying how well. used car saleman bs sales line, yet really sold because of problems . 

op grab a shop manual and set the governor up ,


----------



## classiccat (Mar 1, 2014)

maybe it's the camera angle but there's a spring at the top-right part of the throttle control assembly that's bugging me. 

it looks like it's attached to the governor arm...if so, it appears that this spring would hold the throttle at WOT.

...and +1 on getting a service manual & tachometer!


----------



## 10953 (Sep 4, 2017)

classiccat said:


> maybe it's the camera angle but there's a spring at the top-right part of the throttle control assembly that's bugging me.
> 
> it looks like it's attached to the governor arm...if so, it appears that this spring would hold the throttle at WOT.
> 
> ...and +1 on getting a service manual & tachometer!


your right about the top one not the little one around the linkage arm . it should pull the governor arm back and it's not. 
op needs to make sure the gov is set up properly and not blown inside the motor, 
he's been pm'ed with a link to the shop manual


----------



## dmm26 (Oct 29, 2017)

Suggestions on a tach?

I have the service manual from briggs should be good now.


----------



## classiccat (Mar 1, 2014)

I have a few Hardline tachs / hour meters. they're nice; you simply wrap the wire around the plug wire. even though it's a 4 stroke engine, every rotation gets a spark (one spark wasted on the exhaust stroke). 

do you have the engine part number handy?

I'm fairly certain that the smaller spring (that's stretch at low-speed) in the middle of the video view is the governed idle. The upper spring in the video view is for high-speed RPM control.

it's critical that you 1st set the static governor calibration according to the service manual that 87ps pm'd you; you're basically getting the throttle butterfly, governor arm & internal governor spool all on the same page. Think slow-cam = WOT. You can tweak your RPMs once that's set and the engine is warm.


----------



## dmm26 (Oct 29, 2017)

Thanks for the help guys.

Problem solved. Really wish I had a tachometer to get it exact.

I'll probably get one


----------



## 10953 (Sep 4, 2017)

dmm26 said:


> Thanks for the help guys.
> 
> Problem solved. Really wish I had a tachometer to get it exact.
> 
> I'll probably get one


ok know! what did you find?? had to be a simple adjustment as we felt


----------



## dmm26 (Oct 29, 2017)

Just had to adjust the governor linkage.
Went all the way clockwise and had to adjust it counter clockwise a bit.

Would've been nice to have the tach to get it perfect.


----------



## classiccat (Mar 1, 2014)

dmm26 said:


> Just had to adjust the governor linkage.
> Went all the way clockwise and had to adjust it counter clockwise a bit.
> 
> Would've been nice to have the tach to get it perfect.


Regarding the initial static governor arm calibration, you don't necessarily need a tach to do that initial static calibration; that's only for setting the wide-open throttle position with a bottomed-out governor spool (slow cam). With that said, I still recommend having a tach onhand to make sure you don't grenade your engine. For example, if the internal governor spool is malfunctioning (stuck "out") when you calibrated WOT, there's no more governor spool travel to close the throttle butterfly. That's obviously a recipe for disaster.

The RPM adjustments (_in your case, idle and high-speed_), you're adjusting spring tension (_i.e. bending a tab that holds the spring, spring-tension screw, etc._).


----------

