1987 420SEL 150k miles..good for another 150K?
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1987 420SEL 150k miles..good for another 150K?
I am looking at a 1987 420SEL w/ 4.2L V8. It is in excellent condition inside and out except for small tear in front passenger seat. It seem swell cared for and has almost 150k miles. I have heard things about the indestructible Mercedes diesel being good for a virtually trouble free 300k miles. My question is whether the V8's and V6's for that matter of the early 90's and earlier years are usually tagged with the same indestructible title. Can anyone help with this? Mabye by telling me what you have and with how many miles as well?
Thanks,
Adam Bowers
Thanks,
Adam Bowers
Newbie
Joined: Oct 2002
Posts: 2
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From: Michigan
Buick Park Ave Ultra
There are two reliable indicators for the condition of MB engines:
1) Oil Pressure,
2) Smoke at startup.
To check smoke, start engine "cold" and observe any smoke from the exhaust for 3-4 seconds. The "smoke" from an MB indicates worn exhaust valve guides or at least usually worn valve seals. This is not as prevalent on the vintage of vehicle you are considering, but was common on older benz's, that had a hard plastic seal, that would smoke at 120,000 miles.
At any rate, if you observer smoke at cold start, then valve seals or valve guides are indicated- cha-ching.
To check oil pressure, take vehicle on a run and get the engine up to full operating temperature. All MB's will peg the pressure needle above 1,500 rpm. However, you should check for:
1) pressure at idle, hot, transmission in neutral. An engine in good condition will register at just above, or barely below the 2 bars mark (30 lbs on older models). Any less than that, indicates some wear of some type.
2) Check pressure at engine at idle, hot, transmission in gear: Pressure should register at no less than horizontal, i.e. half way between 1 and 2 bars (15-30 lbs). Better engines will register just below the 2 bar (30 lb) mark.
Any pressure reading near the 1 bar (15 lb) mark, indicates wear. Find another, or get a very good price.
Leslie in MI
1) Oil Pressure,
2) Smoke at startup.
To check smoke, start engine "cold" and observe any smoke from the exhaust for 3-4 seconds. The "smoke" from an MB indicates worn exhaust valve guides or at least usually worn valve seals. This is not as prevalent on the vintage of vehicle you are considering, but was common on older benz's, that had a hard plastic seal, that would smoke at 120,000 miles.
At any rate, if you observer smoke at cold start, then valve seals or valve guides are indicated- cha-ching.
To check oil pressure, take vehicle on a run and get the engine up to full operating temperature. All MB's will peg the pressure needle above 1,500 rpm. However, you should check for:
1) pressure at idle, hot, transmission in neutral. An engine in good condition will register at just above, or barely below the 2 bars mark (30 lbs on older models). Any less than that, indicates some wear of some type.
2) Check pressure at engine at idle, hot, transmission in gear: Pressure should register at no less than horizontal, i.e. half way between 1 and 2 bars (15-30 lbs). Better engines will register just below the 2 bar (30 lb) mark.
Any pressure reading near the 1 bar (15 lb) mark, indicates wear. Find another, or get a very good price.
Leslie in MI
Junior Member
Joined: Apr 2002
Posts: 40
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From: Perth, Australia
W124 230TE, W123 280E
the timing chain can also cause problems on the M116/M117 V8's fitted to these cars.
Start the car cold. If you hear a rattle from the engine for a few seconds, CHANGE THE TIMING CHAIN. A broken chain results in many bent valves!
Trent
Start the car cold. If you hear a rattle from the engine for a few seconds, CHANGE THE TIMING CHAIN. A broken chain results in many bent valves!
Trent
