B+S Professional ReadyStart 7.75 pressure washer model 11675 020429 SN 10 0410 62 40300 starts easy and runs good when cold. If it is shut down, will not start until about 30 minutes of cool-down. It has some kind of automatic choke.
Won't start when hot
- Thread starter mirles
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mechanic mark
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Engine cooling fins clean under blower housing?
Post engine Model xxxxxx, Type xxxx, Trim xx Code xxxxxxxx from engine plate, sticker, or stamped on engine.
Post engine Model xxxxxx, Type xxxx, Trim xx Code xxxxxxxx from engine plate, sticker, or stamped on engine.
You need spark, fuel and compression to get the engine to run. Next time it happens remove the plug and see if it is wet. Dry means you’re not getting fuel. Then check for spark. An inline spark tester is best used for this, so you can check for spark under compression. As it runs cold I doubt you have a compression problem. Have you tried a new plug?
I suspect it's not getting fuel. I am curious as to why it won't even get enough fuel to start when hot, but yet has plenty of fuel to run hot.
mechanic mark
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I had similar experience with an autochoke Briggs on a lawnmower. If spark is strong then I suspect that the hot engine is evaporating the fuel before it can ignite and a little choke would solve it. But the autochoke won’t let you apply light choke. The thermostatic controlled lever is keeping the choke wide open. So, do what you can to keep the heat down. Thoroughly clean the cooling fins and engine. If it still won’t restart after running, I’d experiment by blowing some air on it with leaf blower or compressor. If that solves it, you know it is a heat problem.
You can replace the autochoke with a manual choke but that seems extreme when the solution is to either not shut it down or to let it rest for 30 minutes.
You can replace the autochoke with a manual choke but that seems extreme when the solution is to either not shut it down or to let it rest for 30 minutes.
I could be wrong, but it sounds like it is hrydrolocking, check how much oil is in the engine, if there is too much when the engine gets hot the oil expands and won’t let the engine start, then after some time, usually about 1/2. hour, the oil cools down and then you can start it again.
It's been a while since I posted. In the meantime, I tore it down enough to see the "automatic choke." Yes, it is the high-tech choke (like I had on my 66 Valiant years ago) that hangs open. Open choke prevents it getting enough gas to start hot, or warm. I took a piece of stiff wire and made a manual choke.
Thanks for all the replies.
Thanks for all the replies.