Briggs and Stratton 3.5HP help needed

[JLH911]

Engine is off of an Edger.

It's a 2002 model and I got it dirt cheap at a garage sale.

I've got it running after changing the carb diaphragm and cleaining it out, but now when it runs, it idles up and down.

I noticed that the throttle linkage that's hooked up to the spring that goes to the governor, keeps trying to adjust by moving back and forth.

Anyone got any ideas what it could be?

Oh, and I changed the oil, air filter and spark plug.

Thanks

 

[john_eckels]

The Carb, primarily the jet may still be dirty. My Honda does that when there is the slightest amount of blockage. I use a piece of wire to clean out the tube for the jet.

 

[D'Animal]

Double check the carb cleaning as John recommended. In 2002 it is a guess if it has an adjustment screw. If it does back it out since it is running lean.

 

[JLH911]

Double check the carb cleaning as John recommended. In 2002 it is a guess if it has an adjustment screw. If it does back it out since it is running lean.

I'll try that. It does have an adjustment screw.

I'll remove the needle and clean it out again, could still be dirty.

Thanks and I'll keep you posted.

 

[rockcrawler]

That symptom is usually caused by installing the spring and washer on the tank instead of the carby.

 

[JLH911]

That symptom is usually caused by installing the spring and washer on the tank instead of the carby.

Are you talking about the short spring with the metal ring that fits on top of the spring? If so, it's in the Carb and not the tank.

Thanks

 

[rockcrawler]

Yep thats the one.

In that case I'd be looking for vacuum leaks; rubber that connects to carb from PVC tube and manifold.

 

[JLH911]

Yep thats the one.

In that case I'd be looking for vacuum leaks; rubber that connects to carb from PVC tube and manifold.

You know what? The hose that you're talking about did have a cut in it but I sealed it. Perhaps it's still leaking a bit.

Thanks!

 

[rockcrawler]

No problem, put a small clamp on it on the carby side which is where it normally leaks from. It's also quite common for the intake tube to be loose which doesn't cause too much of a problem until you take the carby off which pulls it out of the manifold. Not something you'd notice unless you know about this. The only way of checking it is with the carby off.
https://forum.ih8mud.com/workshop-h...riggs-stratton-mower-service.html#post4566459

 

[JLH911]

Hey rockcrawler. thanks for that link.

Well, I got it running a lot better once I turned the needle adjusting screw in a bit. Now it runs pretty much consistently smooth except about every 20 serconds or so it has a little "hiccup" kind of thing to it. Don't know what that could be. Maybe some more stuff floating around.

I did notice some rusty sediment at the bottom of the gas tank(This newer edger had been sitting around a while)I think I got most of it out this time, but something might have found it's way in.