Cold Weather Running

[mick m 19]

Hi people. This particular problem has me stumped, along with everyone else I've talked to.....

 

I have an 18 hp Vangard, about 2 years old & recently its been back firing like its Chinese New Year. Some how & from somewhere, its picking up moisture in the rubber breather pipe from the crankcase. The tube is coated with a milky oily/water mix, which is being sucked into the throat of the carb, causing the back firing problem. Where on earth is this coming from?

Cheers in advance for any heads up anyone can give me.

Mick

[mick m 19]

...Annnnd we back trend setters. Was  having a beer yesterday with a mechanical fitter.......He thinks its the oil viscosity. Although I am using B&S approved oil, he's thinking its getting whipped into a foam in the  crankcase, & foam being lighter, is getting sucked up from the crankcase, thru the breather tube to the carby.

Following B & S guidelines, I have filled & changed the engine with 5w 30. A lighter oil for sure, but that's what B & S recommend below 5deg Celsius

Any thoughts? Anyone?.........

[Guy B 70]

Makes sense to change to a lighter oil because of low temps......I've never read anything like your problem, I too will be interested to see other input.

[mick m 19]

Should have mentioned that after the rubber tube has been cleaned out, it takes about 3 days for the problem to re surface again. Checked the tube again today, & after the lighter oil change, & there's just a ''hint'' of water in the tube. As in when its squeezed, you can just see it moving about as the tube is rolled between your fingers.

Sooooo. What you say you?

Is it the oil,. or is there some other cause I haven't considered?...........

[mick m 19]

Well, its not the oil. Still happening, but I've diverted the breather hose & plugged the hole it used to occupy. You can now see a slight spray of water on start up coming from the hose. I'm starting to think "head gasket", but its running sweet as a nut. You'd think it would be running rough tho. Stay tuned.