I bent a push rod for one of the exhaust valves, replaced it and still had backfire issues. When I replaced it and tried to set the lash I noticed that the spring on the exhaust valve was shorter than the other 3 springs by almost 1/4". I had to adjust the set screw deep into the lock nut (compared to the others) Could my valve be stuck open slightly or is this a weak spring. After replacing the pushrod I rebuilt the carb, changed the oil, filters etc. everything was running great, had power again with some backfire until it warmed up. Completed the lawn and figured I could redo the heads down the road. One week later pulled the Derby out to mow and upon starting the blades lost power. As I tried to throttle up and down to warm up the motor, the governor spring came off. I replaced it (probably incorrectly) and now cannot idle the machine, it is running very fast. Does anyone have a diagram or commercial repair manual for the 44000 series B & S 25hp OHV? I have the parts list but it does not show the springs connected or the position of the throttle arm etc.
Looking forward to any advice, pics ect.
Thank you, ML
#2
Arwing64
Check on Briggs and Stratton's website. You can aquire a manual by entering your model #, code, and type.
From the B & S web side you can download the Owners manual and the parts book in about a dozen languages.
But you can not get a service manual, they have to be purchased.
Some one here cross referenced this post a while back, God bless his worn out fingers.
Some of the links ar a bit funny and if you choose to save a copy please check the diagrams & photos.'
For some reason I could view themon line them but they did not appear in the saved copy.
If you have trouble locating a Service Manual, I can send you one, address below, put in proper format and remind me model number and what you want.
When ever you have a bent push rod you need to try to find out WHY. Two main reasons is slipper valve guide or sticking valve. Moved valve guide s usually due to cooling problem from plugged cooling fins and or cooling shroud. IF sticking valve, top cylinder lube may help.
I have fix for slipped valve guide also.
Walt Conner
wconner5 at frontier dot com
PS: Valve springs are all the same length, IF one is actually shorter it must be broken perhaps causing your engine to run on one cylinder.
