My diesel engine won't start anymore when the temperature drops. What are my options?

Dear Car Talk

Dear Car Talk | Jul 01, 1997

Dear Tom and Ray:

I have a 1982 Mercedes 240D with 210,000 miles. In the warm months, I have
no problem starting this car. But for the past couple of winters, it
struggled to start when the temperature fell to around 40 F, and refused to
start when it got to 30 F and below. However, a shot of ether does bring
her back to life. I asked the local dealer service representative about
this and he had two suggestions. One was to install an engine block heater
for about $19.95. The other was to install an engine for about $7,000.
What's your thought on this? -- Russell

RAY: Well, assuming the dealer is sure the glow plugs are working, I think
he's outlined your choices rather concisely, Russ. The problem is bad
compression. Diesel engines rely on compression alone to raise their fuel
to a combustible temperature. And when diesel engines' rings wear out and
they lose compression, it's curtains for them.

TOM: The block heater would merely simulate the higher outside temperatures
in which your car still starts, but eventually that won't work either.

RAY: So it depends on how long you want to keep this old beast. If you love
it, and it's otherwise in good condition, and you want to drive it forever,
then put an engine in it. I mean, $7,000 is less than you'd spend on a new
car, right?

TOM: If you just want to keep it for a while, but don't like the idea of
"forever," you might look into getting a used engine at a junkyard. That's
a less expensive, although not inexpensive, option.

RAY: If the car is rusting away, or the transmission is shot, or if you're
just sick and tired of it (this would be perfectly understandable,
Russell), then you might try the block-heater approach. That's just a
Band-Aid, but who knows? Maybe you just want to get through one more winter
and then sell it to some unsuspecting in-law -- in July.

TOM: One final option we'll offer you is the instant self-destruction
approach. If you hate this car so much that you only want it to last a few
more days or weeks, then keep using the ether as a starting fluid. Ether is
an absolute "no-no" in diesels. It's so explosive that when combined with
the high compression in a diesel engine, it tends to blow head gaskets
faster than you can say "car loan."

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