VW Engine

When Westeraskmaskiner/AKTIV and Kristi installed VW Aircooled they broke some of VW's Cardinal Rules concerning Cooling. In a VW there is elaborate tin and rubber seals that are critical to operation. They pulled the cold air in over the engine, then thru the engine and exhausted it out below the engine to the outside air. Snow Trac draws the air in an air intake horn adapted to the fan housing, and mated to the hood. The exhoust hot air came out all around the engine, and blew out the front. They also screwed up by putting the exhaust INSIDE the engine compartment. The only reason they didn't have more overheating problems than they arleady do is that they are run in the winter when the ambient temperature is low. The company had lots of problems in this area. They tried adding fans. Private individuals added oil coolers.

If you run your machine in the spring, and the Ambient Temperature is at or above freezing you will likely experience overheating problems. Make sure all the 'Tin' is in place. Re-route the exhoust out of the engine compartment. There are 5 exhaust arraingements. the first 3 are Snow Trac, the later 2 are actually something NW Tell out of Canada came up with. The earlier systems ran the pipe around the engine coming narrowly close to one of the small sprockets on the Variator, then it ran out of the engine compartment under the rig and came out the side. This had a tendancy to let exhaust migrate into the wing window when the rig wasn't moving. The pipe was so close to one of the drive chains that on more than one ocassion the master linc got knocked off leaving the operator stranded. Get this pipe out of the engine compartment!

We ( Ron Hoffman, Lyndon Strother,Niel Fennessey, & Earl Lasher of the original ST4 owners association) did some extensive testing or the cooling problems by locating temperature sensors all over the engine compartment. what we found was that if you punch 4 silver dollar size holes just under the muffler, it drops the engine compartment temperature by 25 to 35 degrees. The single best other thing you can do is to have the Fuel/Air Ratio adjusted. they do this in recriprocating engine aircraft. If you are going to be "Flying" your snow machine at an altitude above 3000 Ft, I recomend having it set by someone with an engine gas analyzer (The machine used for polution testing many places). Also, according to John Muir and the "Idiot Book" you should advance the spart one degree for every thousand feet above 3000 feet. Really the fuel/air should be adjusted to the anticipated operating level too. Too lean and it will run hot. Too Rich and it will run cold. Early machines didn't have the auxilery fan. The last machines also didn't have the Auxilery fan. On my machine that has an aux fan, I have it adjusted to where I don't need the fan except on long heavy uphill climbs. I remove the belt and but a wood stopper in that side of the air induction housing so that it won't suck hot air out of the engine compartment right back into the fan.

Lyndon, one of the problems with my ST4 is that the former restoration left me with an exhaust that blows straight forward. This means I drive into the exhaust and it is not a good thing!!!

Villi sent me some photos of his near stock exhaust set up, and my plan this summer was going to route my exhaust down and under the rig and then out the right side like a stock exhaust. I already welded the muffler supports in place for this but have not begun to mess with the exhaust system (been working with the tractor tilling the field & getting ready to plant).

So can you post pictures of what you would suggest? I would still like to go under the machine, I'm thinking that I may exhaust out the very back, or perhaps bend it up and exhaust at the roofline in the rear.

Below is a photo of the front of my ST4 where you can clearly see the exhaust sticking straight out the front!!! (front driver's side, chrome tube sticking out of the grill)

Looks more like a gun barrel to me .

BigAl said:

Looks more like a gun barrel to me .

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Well I can tell you it is not a good thing, especially on days when the wind is not blowing. Anytime you can drive with a cross-wind is good. But on days when there is very little wind you don't want to sit at idle very long. And even driving forward is not the best thing.

You can see the exhaust behind the lower grill, it comes from the lower left up to the upper right. My thought was to run it back under the cabin like Villi did, and like the original set up would be.

Lyndon wrote to me (in part)

Highly recomend that you run the exhaust out the front on the passenger side, down the whole length of the machine and up the rear. . .

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As I am a flatlander and don't need excessive ground clearance, I'm not sure I will take his advice exactly. I do like his idea of running the exhaust up the rear of the machine. I also like Lyndon's idea of running it up the hinge side of the door so people are not tempted to grab the exhaust pipe and use it as a handle But I am worried about the heat build up and I may punch through the lower sheet metal and run the exhaust pipe outside of it (which will reduce my ground clearance at that point) and to the back under the machine and then up the back wall.

Thoughts?

After using mine for this last winter I never experienced any exhaust fumes in the cab. Dmiesner's has a dual set up like mine but one going left and the other right. Its built into the front bumper. The bad thig was when I went to look under his Snow Master and grabbed a hold of the frint bumper. Can you say HOT! I played it off pretty well though. Anyway I still like the idea of it going outback and up. I just cant figure out a way of really doing it yet. If it goes under you cannot have any joints. Heres a picture of my set up.

BigAl said:

Looks more like a gun barrel to me .

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Laugh it up fuzz ball! Thats for blowing STUCK Kristis completely off the trail. Its really a howetzer! Sorry Bob I couldnt keep the secret any longer.

If I am towing you out of trouble again and you shoot me in the Ass <-- (English spelling is Arse) ,who is going to save your sorry ass ??<-- (American spelling for Sorry Ass)

OK former Grand POOPa. I see how it is. That sounds like a Kristi KT7 VS Snow Master shoot off! Will we be racing for pinks? I have a course already set up. We just have to wait for a good winter storm to hit.

OK heres a great VW engine thread.

Hey Mike .... I think you forgot to add the link.