The Stovebolt Site Forums The Shop Area Engine Shop how to service road drat tube

1954 Chevy 235ci. How do you service the road draft tube? Take off and soak in kerosene? I could not find anything with the search engine.

Hy Redbird, that sounds good to me kerosene, varsol any good cleaning solvent let it soak for a couple of days and then flush through it. Have a look at it with a flashlight when you get it off, it may not be too bad.

Back in the day they burned it out. Used a torch or simply stuck it in the fire. That's how I have done two of them and when I fire up the wood furnace next month I will burn off the one for the 54 3100.

First use anything non-petroleum that is made to loosen up sludge, rinse it out and try again.

I was cleaning one for weeks then realized it was impacted badly. I tried kerosene, it helped a little but not enough. I put it in a old washing tub outdoors and away from anything that would catch fire. I got the tube hot with a propane torch. The sludge self ignited and burned itself clean (white inside). It sounded like a small jet engine. It belched a lot of black smoke and I suspect it was toxic. Be careful if you try this folks. Hours later after it cooled down, with respirator on I blew it out several times with an air hose. Then I sprayed some lube inside to keep it from rusting then wiped the exterior down with lacquer thinner. Primer and paint then reinstalled. The engine ran better.

I got lucky with the sequence. Right after cleaning the draft tube, I replaced the valve cover and lifter oil galley cover gaskets (the traditional way, including flattening the sheet metal). Hey! The oil leaks went away. Only a slight weep typical of all cork gaskets.

Will the draft tube sludge up again. On an engine with worn piston rings, you betcha.

Thank you guys. We don't dare light a fire around here at this time. We are under a "fire ban""!

Is this something that should be routinely checked on my 49 3100 w52 216?

Probably only if it starts blowing oil vapor out the valve cover vents.

If it was, it would be in the shop manual.
You have to consider that many of these old truck engines are well passed their normal service life.
Nobody wants to rebuild them, especially the 216, because of the expense.

If this is something that really bugs you, you could buy a used one to clean and swap out.

I'm glad you made that comment. The way mine is marking its territory, I should clean my road draft tube out- I know it won't fix a real leak, but anything to discourage the oil from looking for the exits could help.

buoymaker In the olden days we burned those out with gasoline till we could knock out the sludge chunks !!

I converted mine to a PCV and ran a pipe off of that to the manifold.

WEb old PCV is best ,If there is a slight suction at the oil leaks may help keep oil in,however it's important to not put a vacuum on the crankcase. It will give you a funny feeling when it colapses the tin wear on your engine !!