Briggs & Stratton compression

viperv10

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Hi guys, I'm new here. Someone gave me a White push mower with a B&S engine that looks to be at least 20 years old, 5hp, to see if I could get it to run.
It has good spark but won't start. I checked the compression and it only has between 55 and 60 # of pressure. I didn't know if this was enough to run or not.
When I tried the primer bulb, no gas was squirting into the carb. I took the bowl nut off and cleaned it and the bowl and sprayed some carb cleaner through the carb opening and up the main jet. The primer started to work but still would not fire. It would fire for about 1 or 2 seconds with starting fluid but then stop. I'm used to working on Lawn Boys and their carbs are so easy. This thing has so many levers, springs and linkage I'm about half afraid to try to take the carb off for fear of not being able to get back together right. I just wanted to get someones opinion about the compression. Maybe its just too low to run?
Any thoughts or suggestions would be appreciated. Thanks.
PS It was built in 1993
Jerry
 

EngineMan

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Hi guys, I'm new here. Someone gave me a White push mower with a B&S engine that looks to be at least 20 years old, 5hp, to see if I could get it to run.
It has good spark but won't start. I checked the compression and it only has between 55 and 60 # of pressure. I didn't know if this was enough to run or not.
When I tried the primer bulb, no gas was squirting into the carb. I took the bowl nut off and cleaned it and the bowl and sprayed some carb cleaner through the carb opening and up the main jet. The primer started to work but still would not fire. It would fire for about 1 or 2 seconds with starting fluid but then stop. I'm used to working on Lawn Boys and their carbs are so easy. This thing has so many levers, springs and linkage I'm about half afraid to try to take the carb off for fear of not being able to get back together right. I just wanted to get someones opinion about the compression. Maybe its just too low to run?
Any thoughts or suggestions would be appreciated. Thanks.
PS It was built in 1993
Jerry

B&S don't say what the compression should be, 90psi would be better but should run on 55-60 its more then likely be the a carb problem, take photos or notes of how you take it off and apart, post up the model number you should find it on it somewhere, that way we will know what you have and maybe help you with some pics...!
 

viperv10

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Thank you for your reply. Model no. 124802 type 3110-01. If I were a betting man I would say it a carburetor problem also. I'll have my wife take a picture or two with her tablet to help put it back together.
Jerry
 

EngineMan

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If you need the full parts list let me know.
 

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viperv10

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Thanks fellows, I'm sure I will find some useful info from this. I just have to find some free time to work on this. Too much overtime at work right now. I'll get back to you when I get into this or if I run into any problems. Thanks again.
Jerry
 

viperv10

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Well I took the carburetor off. It was a lot easier that it looked. Most of the linkage stuff stayed on the mower. It had a Walbro carburetor that I am familiar with. I gave it a good cleaning and put it back on and ran out of time. Had to get ready for work. Maybe I'll get back to it this weekend. I want to empty out the old gas, put on a new fuel line and clean up the flywheel magnets and coil a little bit. They are a little rusty. I think this must set outside. When I tried to
pull start it, the rope would not retract. The metal dogs were stuck so I got out the WD40 out and oiled them and the recoil spring and it works like new again.
Over and out for now.
Jerry
 

viperv10

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Well fellows after regapping the coil and putting everything back together with some fresh gas it started up on the 2nd pull. It surged a little for about 30 sec. and then it smoothed right out. Oh the sweet smell of success. I'm just a novice when it comes to 4 stroke engines. I do tinker with Lawn Boys, so I better get out of here before I get kicked out. Thanks again,
Jerry
 

Scrubcadet10

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MOST mowers i have seen (push mowers) are usually 95 to 105
 
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