Blow-by Tube Discharge

[shootiniron]

Whats acceptable vs. not acceptable blow-by comming out of the tube on the multifuel ?? Thanks!

 

[rockman]

Mine is kind of a wispy like vapor much like a pcv valve on a V8...chevy that is not a Ford...

 

[WillWagner]

A drop or a few out the tube after use is OK, a mess all over the diff that looks like you poured oil on it is bad.

 

[connectingbar]

I noticed that mine has made a mess, but only after I let her idle for quite some time to warm her up to keep the batteries fresh here in NY in sub zero temps. Is this normal? I've read that too long of an idle will do
this. Is this true? Also my tube looked like it was hooked up to the diff ( sat right on top)

I plan on changing it so it will hang below the axle a little bit

 

[jwaller]

it's normal to discharge more if you dont drive it. you need to get it out on the road and get it good and hot to cook all the moisture out of it.

 

[rosco]

More important is, what it does when it is working. Is it using oil? How much? Slow idle is not good, especially in the cold. Those engines tend to run cold. You will see slobber running down the stack. Its far better to pull out the throttle & let her run at 11 or 1,200 RPMS. If your going to leave it run more the 5 minutes - pull that throttle out. I hate the "oil slick" too, but that slow idle contributes a lot to it. Get over worrying about how much fuel it takes to run it!

Lee in Alaska

 

[jimk]

Have you preformed an oil/filter change? If it's unknown, or old, there may be a lot of fuel or water(condensation) in it . These are volatile and make vapor when hot. The rate gas flows out out the tube is a good indication of ring seal. It may decrease as the engine warms and pistons expand. A fast idle is better. It warms the parts/oil/coolant faster minimizing wear. It also throws oil around inside increasing cylinder wall and camshaft lube. An oil change will determine that the dip stick is accurate(over filling can increase blow-by and reduce power). A bad head gasket can increase blow-by, or add water to the oil. Some of the early head gaskets had issues. Mine needed one. Winters cold [ambient] air temp will make blow-by more visible than, say, summer. While undesirable the engine can tolerate a lot of blow-by. Bad blow will contaminate the oil faster.

 

[connectingbar]

I changed the oil few weeks ago, no fuel smell or antifreeze in there. I have only put on @ 50 miles since coming from GL ( registration issues here in NY) Driving it , There hasnt been any exessive drainage out of the tube while driving. Oil level good with no smells. Not being used to these motors I believe not running her to burn out everything. Most equipment I use has a tank to collect the drainage.

I will extend the hose a little, degrease the engine, change the thermostat then take her for a good trip at highway speeds and see what that does.

 

[Lex_Ordo]

I noticed some light vapor coming out once when the truck was warmed up and idling after a drive. I really haven't paid much attention to it since then, but the diff bulb is nice & dry, so I imagine it is working appropriately.