Vented or Non Vented Gas Cap

[woodlandfarms]

OK, I am making a new lid for my diesel tank on the tractor. Looking at just bying a new bung and cap. Vented or Non Vented? Anyone know? When I open my tank the air really sucks in so I am assuming non vented (also, don't forget my tractor goes sideways but supposedly if you keep it below the fill line it won't over flow).

 

[CurlyDave]

As you use the fuel, you must allow air to enter the tank. Otherwise either the fuel stops coming out, or the tank collapses somewhere along the line. I would vote for vented.

 

[Dave M7040]

What age is the tractor and do you have a part diagram for it which should show an external vent line if there is one.
I am not familiar with powertrac

Most modern Kubotas have non vented caps and there is a separate vent line, often with a filter on the end, to keep dirt out.

ATV's and dirt bikes have unvented tanks with an external vent line run as high up under the body work as possible to allow fording of streams.

Dave M7040

 

[woodlandfarms]

No vent line. Just a return line from the injectors.

 

[Dave M7040]

I was looking at the Power Trac web site after reading your original post.
I had never heard of that type and brand of tractor.

I could not find any manuals or parts places on the Power Trac web site.
In view of the side slopes it is designed to work on, having a vented cap would seem to be a leakage problem with a full tank.

Could there be a Tee in the injector return line running up somewhere high on the tractor which would provide the vent.

Many owners of a wide variety of machines have reported problems with mud dobbing flies or wasps building their nests in the open ends of small hoses blocking the tank vent.

Dave M7040

 

[ponytug]

You need a vent somewhere. Whether you want it in your cap or elsewhere is your call. If you put a vent in, it will need to be higher than the fuel level, or you will push out fuel on warm days as the fuel heats up.

Given your water issues, I would vote for a vented cap with drying agent in it.

All the best,

Peter

 

[SpringHollow]

i have a desiccant cap on my hydraulic tank.

Ken

 

[woodlandfarms]

Ken, you are gonna have to get a picture or send me a link. My google fu is not finding what you are on about.

 

[SpringHollow]

These be them:

T.R.A.P.™ Breather

Ken

 

[ponytug]

More information on page 227 and 228 of the main Donaldson catalog. You will need to adapt the existing threads to either 1"NPT or a bayonet. However, there is a clearance issue. The NPT sticks up at least 3" from the tank. The bayonet is closer to 6". Watch your seat for interference.

Ken- didn't you do some engineering to get the clearance necessary to make it work?

All the best,

Peter

 

[SpringHollow]

I drilled a new hole in the cover for mine. Currently, it is replaced by a magnet which I felt added more value. At some point, I will redo my cover to accommodate things better.

Ken

 

[PILOON]

For sure U need a vent.
No vent can cause collapse of lines and even cave in the tank walls but usually the engine stutters and stops B4 any damage is done.
For that matter an engine that is starving for fuel is actually running VERY lean which is the recipe for burnt valves.

 

[ponytug]

Dear Ken,

How often do you clean your magnets these days? Are you still getting a lot of debris? I put a couple on my oil filters, but I have always thought your solution was far superior.

On the subject of oil quality, I did notice that running my PT driving a wood chipper for two hours really improved the response rate of hydroback, almost as if there were dissolved gasses or water in the hydraulic fluid.

All the best,

Peter

 

[SpringHollow]

I clean the magnets every couple of years or when ever i need to open the cover. Last time I did it, there were filings on the magnets.

Ken