Trouble with B & S 13hp Vanguard

Hi,

Yes, I am new here. Some threads from this forum came up in a Google search when I was trying to figure this out, and it seems as though you have some knowlegeable people here, so I'd like to ask for some help.

I have a Briggs & Stratton 13hp Vanguard OHV, model 235432, type 003501, on a Campbell Hausfeld pressure washer. I ran it earlier this summer, and it seemed to run just fine.

A buddy borrowed it, and had it for a couple weeks. After using it, he told me (this is all from him, just through conversation) that some oil had "come out of the carb". His thinking, or what someone else told him, was that the head gasket was bad. He told me he would replace it, and did. He returned it to me after that, but the starter rope had broken, so he had not run it (I asked for it back, saying I would fix the rope, no big deal). I fixed the rope, and then went to check the oil. Upon removing the plug/diptstick, oil and gas gushed from the opening. The crankcase was FULL of it. I don't know if it mostly filled up after he quit using it, or if it was run much or at all in this condition.
That was a couple of weeks ago. Guessing that fuel was leaking past the needle in the carb, I ordered a rebuild kit and a new float, even though the old float did not seem to be leaking or have fuel inside it.
Today I rebuilt the carb, doing everything but the welch plug. I reassembled everything. I of course drained the crankcase and put new oil in it. I figured I would run it a bit, and then change the oil again.
I tried to start it. I pulled it a few times whith full choke, it did not fire. I sprayed some starting fluid into the carb, and it backfired once or twice. I pulled some more, then tried the starting fluid again, still just a couple backfires, some pretty loud. I pulled the plug out of curiosity, it looks brand new. I assume my buddy bought a new plug for it. I didn't think until right now as I am writing this that I should check to make sure it is the correct plug, but I will do that. Assuming for now that it is, what could be the problem? Could it be an issue with the new head gasket or how he installed it? Could I have made a mistake with the carb rebuild (it's not that hard)? Is there something else that I can check or adjust? Any help is GREATLY appreciated!

 

Since you had it full of gas, I would lean towards the engine still has a flooding gas residue in the cylinder.

There could be some other issues, but I normally purge the cylinder and hand feed a little gas to it.

I would get all the gas out of the tank or shut off the gas to the carb with a shut off (if you have one). Then full choke, no throttle, spin it over 5 or 10 times. This takes all the gas out of the carb through the choke.

Then pull the plug and full throttle, no choke spin it over again a few times. This purges the old gas out of the cylinder.

Then put a teaspoon of gas directly into the plug hole. This bypasses any carb issues. Plug back in and full throttle. It should fire and try to run a short time.

Then put gas back in it and half throttle, half choke, see if it will take off for you.

The reason you have to get the gas out of the carb and cut off from the tank is the fuel system will feed more fuel to it and compound the flooding.

 

I see no way a head gasket would have anything to do with oil in the carb.
More likely caused from to much oil, or something's wrong with the valves or piston rings.
Over filling it with oil can do all kinds of damage to an engine.
Blow out crank seals, snap a crack shaft or break a piston ring.

 

I think it all comes down to the leaking carb -----putting gas in the crankcase which overfilled that = oil pushed back up into the carb, then gushed up from the over fill, then lthe gas in the head hydrolocked the engine so you couldn't pull the engine over and broke the starter rope.

So fix the leak, change the oil, and start it up and you'll be in business.

 

joe, I agree with you, and again, that was not my diagnosis. The head gasket was replaced before it was returned to me.
marbobj, I tried the things you suggest, again all I got was some backfiring.
The bad news is, I now have a little more informaton.
While doing what you suggest, I noticed that the plug wire was mis-routed, preventing the throttle from being moced all the way to idle. No, that was not causing my troubles, but while I was removing and reinstalling some bolts to re-rout that wire, I decided to remove the valve cover. I pulled the enging through repeatedly, and only the one rocker arm moved. Oh boy. I rocked the un-moving one with my hand, just to see if it would move at all. It did. I then pulled it through again, and it moved some, but then went back to what it was before, only the one rocker moving. Obviously I have deeper issues than a carb. I probably will remove the head sometime, though maybe not today. Is there a chance that the head-gasket job was the problem, or is it deeper than that?

 

Hah, never mind! The one pushrod was not properly seated. Sometimes I need to look a bit closer before screaming for help or assuming the worst! Put it where it belongs, put it back together, fired right up. Thanks everyone for the help!