Draft Tube Question

[JRBAMATEX]

I don't know if what I am thinking of doing is good or bad. Also not sure if I am just masking a bigger problem. Here's the deal. My draft tube emits a little smoke (Exhaust) when I first crank it up. More specifically it always emits SOME exhaust but more when I first crank it up. Nothing major. Just enough so that you can see fumes creeping into the cab through the transmission shifter hole in the tunnel while warming up. When you crank it at night and you have the head lights on and stand outside you can see a little fume cloud in the head lights. If you start it in the day time and look under the truck with a flashlight and up at the tube coming down above the front axle you can just see a little smoke coming out of it. Then once it warms up this all seems to fade away. So you see it doesn't seem like a major thing. In fact maybe it is supposed to do this. OK.. All this said. Here's what I think I am going to do about it. First I am going to finish making shifter boots to seal the T-Case and Tranny shifter holes in the tunnel. Then I am going to get a big rubber matt to cover the whole floor of the truck so that other little holes like in the M.C. access flap don't let in fumes. But the one really big thing I am thinking of is to attach a 1.5" hose to the draft tube and run it out the back of the truck. I hope to keep the nasty stuff off of the axle and side of the engine and to keep the fumes out of the truck.

Will this work? Is this a bad idea? I really like the filter and sump deal that Bjorn did but I think that might be a little advanced for me.

 

[m35a2cowner]

Draft Tube

Ever see the irony of a DRAFT tube on a MV? Anyhow, why not run a tube over to the bottom of the passenger side wheel/fender. Anything it spit out would be washed off by water and its a lot shorter than the back of the truck. Always point it down so it drains. Just a thought.

 

[Recovry4x4]

I've heard of folks extending it down below the front axle to keep it from getting spooged.

 

[rizzo]

I've heard of folks extending it down below the front axle to keep it from getting spooged.

my m109a3 is like that.

 

[SixBuy]

OK, I'll bite. What's a spooge and how would I know one if I met it in a dark alley?

 

[m35a2cowner]

Spooge

I am sure what he is talking about is a oil-moisture mixture that drips from the tube. Its a normally occurring thing. Sometimes called blow-by. It occurrs more when the engine is cold.

 

[cranetruck]

For you that may be interested, the amount of blow-by is about 1/10 of a quart every 1,000 miles. The liquid portion, that is. The filter shown in the image below in the lower left area, has a sump which has to be drained now and then.
The fumes are guided up to the air intake via the support tube.
The main reason for installing this filter was to make the deuce more "fording ready".

 

[m35a2cowner]

Filter

This must be something that is installed with a fording kit? Mine doesn't have a filter/sump. I did put an extension on the draft tube to avoid getting oil on the starter. Thanks for the picture/info.

 

[cranetruck]

Oh, it's just another cranetruck special.

 

[Recovry4x4]

Spooge is any unwanted slimy substance. Use your imagination. We used the term alot on sex crimes cases.

 

[SixBuy]

Aaahh! Hanky Panky in the Cranky Case! Gotcha!

 

[luapmonn]

You need to be careful diverting Diesel crankcase fumes into the intake. If the engine has a lot of blowby you can end up with a run away engine. Pulling the engine stop won't stop or even slow the engine

 

[cranetruck]

You are right about that. I wouldn't think of doing it if if wasn't filtered. Hopefully the burnable content of the fumes are left in the sump.
I have 10,000 miles on the truck with this system in place and no problems so far.

The Racor Crankvent filter installation instructions suggests open or closed set-ups. The closed version recirculates the filtered blow-by fumes.
In my case the breather tube ends a couple of inches below the mushroom, so it's not 100% recirculated.

The image below shows the TM version of the fording kit installation. It shows the crankcase vent terminated below the mushroom. This configuration is only meant to be left installed for a short time.