Briggs and Stratton L Head - Low Compression

cpurvis

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I CAN be the carburetor unless you tried in on a different engine and it worked. Putting on a new carburetor rules out nothing unless it fixed the problem.
 

gibbywmu

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Thanks Tom! That's exactly to the point where I'm at now. I actually bought a nice Craftsman 2800 psi unit w/ the Easy Start Briggs and Stratton. Love it! Was just hoping to fix this one up and sell it. Good point about the valve guides.....but if that's the issue that's a little beyond me. No feeler gauges, leak down testers, etc. to diagnose further.
 

gibbywmu

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I CAN be the carburetor unless you tried in on a different engine and it worked. Putting on a new carburetor rules out nothing unless it fixed the problem.

Carburetor was previously tested on another pressure washer I have that ran completely fine. Carburetor has been ruled out.
 

gibbywmu

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Guys,

So we have some life. My mistake. It was a new carburetor, but somehow when I installed it, the diaphragm was not right. I pulled it off and sure enough, it had a hole in it. No worries as I had a spare diaphragm. Installed, engine ran great right away! (No pump on). Now, here's where the trouble lies. When I installed the pump (this is a brand new Annovi Reverberi pump, the same style that are on my other 3 pressure washers), it start to run for about 1-2 seconds, and shuts off immediately. Its like with the load of the pump on, it can't handle it. Shuts off right away. I turned the water supply off, disconnect the hoses, and fired up again. Runs perfect with no water supply. Only let it run for a couple seconds so the pump coudn't get damaged.

Now...........why with a new pump does the engine want to stall out immediately if it runs fine w/out the pump on? What am I missing here?
 

cpurvis

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Here's how I start my power washer.

Connect water hose, turn on water.

Squeeze trigger to purge air out of system.

Shut off water.

Start engine.

Leisurely walk over (no more than 30 seconds) and slowly turn on the water. This gives the engine a chance to warm up a little before full load hits it. My pump book says no more than 3 minutes without spraying.

In your case, the carburetor may AGAIN be causing you problems if the main jet is not passing enough fuel to allow a cold engine to pull through a sudden load.
 

gibbywmu

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Cpurvis,

That is a good point about the carburetor. Even though it’s brand new, I could take it off and clean the pickup tube anyway. At least rule that out.

About the pump, I can’t see it staying started with any resistance, whether there is water in the pump or not. Your steps make total sense though, and I’ll at least try that tonight.

Is it still a possibility the Piston/Rings or Valves have something to do with it? Engine sounds good with no pump on.
 

tom3

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My son starts his up with the spray head removed and the wand trigger tied open. Will pump some water but no pressure to deal with, then let off the trigger and see if the pump goes up to pressure and unloads. Could be a stuck unloader?
 

Telesis

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Annovi Reverberi makes several pumps that all look the same but specs are different(1900-2800psi in vertical plunger pumps). I see the Husky was rated 2200psi. If you put a pump on that's spec'd at a higher pressure, it can be a bit too much of a load. The good news is you can back the unloader pressure setting off, which lowers the effective pressure, but also lowers the load on the engine and that big 'kerthunk' you experience when you let go of the trigger on your wand. You don't need any special tools to do this. Just an adjustable wrench. I attached a pic for those who may not be familiar. (the wrench is on the 'cap' I refer to below)

Since the pump is brand new, that unloader cap is tightened all the way. You can easily experiment to see if lowering the pressure keeps from killing the engine but still produces sufficient pressure. By turning the cap counterclockwise a quarter turn at a time, you can see if this makes a difference. [You can accomplish the same thing by adjusting the set screw on the end of the cap that's locked down with the 10mm nut. (takes a 3mm allen key) This is set at the factory and painted red. No need to mess with that to test if this helps]

It sounds like you may own multiple power washers. You may want to consider investing in a pressure gauge(0-5000psi fluid filled with quick disconnect fittings). They are only around $20 and can tell you a lot about what's going on.

Give it a try!
 

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gibbywmu

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Telesis,

Thanks a bunch! Yes, I'm very familiar with these AR pumps. All 4 of my pressure washers have the exact same AR pump. Now, whats interesting to note..........is that my other Troy Built (model 020245) is also a 2200psi unit and has the exact same AR pump on it. Never had this issue of not starting because the pump was rated too high for the motor. So, I don't think this particular AR pump is too high of a load for the Husky (Briggs and Stratton) motor.

Good point on the unloader being tightened all the way. Let me try and back that off for several starting attempts and see what happens. My only other course of action from this point is swap carbs and the same AR pump off my Generac and see what happens. It basically has the exact same B&S engine as the Husky unit.

Give me a few hours and I'll keep you posted!
 

gibbywmu

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*UPDATE - Problem solved! I tore the carburetor off again (which I had done before and noticed a torn diaphragm....strange as I've replaced many of these. Must have installed incorrectly or damage from overtorquing the screws???)....I noticed some small pieces of what I thought were rust in the carb bowl. I know these tanks are notorious for rust, so some must have gotten pulled from the bottom of the tank. This makes perfect sense.........since everytime I would try and start with the pump attached, requiring more fuel of course, it could not start.


I started messing with the unloader valve as I think AVB mentioned..........loosened for less pressure. It started running better and better after screwing with it. That's when I realized it wasn't the unloader valve (which I didn't think it was, this pump is brand new) I tore the carb off and saw the rust pieces or whatever they were. The engine was trying to get more fuel but couldn't and would stall almost immediately.


So, thanks again! I think Cheese mentioned too.......it seems most of the time on these smaller engines its a carburetor issue!
 
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