How do you 'undo' WVO effects?

[PackerEdgerton]

Hi guys!

A friend of mine has a 1979 240D with 4 speed manual transmission.

Symptoms:

• Smoky startups (white/blue, smells like oil)
• Lots of blow-by (whoo-hoo! It's a geyser!)
• Smoke clears after it is warmed up.
• No black smoke at all at any time.
• Power is lower than normal (e.g. compared to my 83) but otherwise runs normally after warmup.

Evidence of weirdness:
I went out and looked at the car. AHA! What do you guys make of this? It looks like a heat-exchanger that has been plumbed in-between the fuel tank and the heater hoses! Certainly my 1983 240D doesn't have anything that looks like that... From what I can see, it appears to be a set of copper tubes with the heater hoses hooked up to it, and a copper coil running in a helix around the copper tubing. The whole thing is wrapped up in some kind of foam insulation! (See the picture)

I have got to assume that this was to heat the fuel as it comes from the tank, and I also assume that this is for SVO/WVO use. What do you think?

If this is the case, then I would think it stands to reason that his significant blow-by and and smoky startup might be caused by excess carbon and varnish in the cylinders caused by WVO use?

OK, if this IS the case, then what is the cure for all this? Is there a cure?

Thanks,

PE

P.S. We did do a MMO piston soak for a couple of days, and also ran Kreen in the sump for 200 miles (boy, that stuff STINKS!). I drained the oil, and it was black as night! Right now it has normal fill of Delo400 15W-40 Diesel Motor Oil with a Mann filter.