72 280sel wont start! - PeachParts Mercedes-Benz Forum

awarne · #1 12-13-2002, 05:09 AM

for a while the car wouldnt restart if the car was hot. A friend told me maybe the coil. then i parked for a month and tried to start and it wouldnt turn over , thought maybe the batt. was low then charged batt. and still nothing when i try to start like when it was hot before but its cold so im confused? does it sound like a coil and if so would the fireball xr 700 replace my coil or would i need a coil still.

Thanks, AARON

Aaron · #2 12-13-2002, 02:40 PM

Sounds to me like you have a vapor lock problem.

skalie · #3 12-13-2002, 03:08 PM

This may be way off the mark, but I had a diesel motor that wouldn't start when hot.

Diesel motor may be a biotch to get going in the cold, but once you've got them running they shouldn't be a problem restarting for the rest of the day.

Turned out to be the starter motor, the spindle I think you could call it was bent. There were two copper washer / bearing / tube things at each end of the starter motor, they were worn.

I replaced them, then found I needed to replace them regularly, ended up getting a new spindle or whatever the guts of a starter motor is called. Problem solved.

.............um.......er......... symptoms for this prognosis are the starter motor not turning the motor around fast enough to start it.

awarne · #4 12-13-2002, 05:30 PM

whats vapor lock and how do i fix it

Tomguy · #5 12-13-2002, 10:15 PM

Vapor lock is when there is negative pressure in the gas tank (with respect to the outside environment) and the pressure is too great for the fuel pump to overcome it. Buy a newer style gascap that has a vent on it. To see if it IS vaporlock, try starting the car with the gas cap loose.

awarne · #6 12-13-2002, 11:29 PM

but my car wont even turn over. the starter has always worked great, maybe my ignition but my buddy said it was the coil and that doesnt make sense either because what does the coil have to do with the starter

skalie · #7 12-14-2002, 03:36 AM

Be aware that batteries can die suddenly, as in finito pronto.

They will still read 12V, but not have enough oomph to turn over a motor.

Eliminate that variable first, i.e. try another battery.

Tomguy · #8 12-14-2002, 01:20 PM

He said he changed it :p

Have you eliminated the chance of the engine being frozen? If it's been sitting that long... And it definetly is NOT the coil.

psfred · #9 12-14-2002, 01:23 PM

Several possiblilties Aaron:

Bad battery -- if it won't provide enough current, it won't even spin the starter.

Bad battery cables or bad engine ground. No connection, no starter, no start.

Bad solenoid on the starter. The solenoid snaps back when you turn the key, shoving the gear on the stater motor into the flywheel gear and at the same time closes the contact for the starter motor. Either the solenoid is sticking or the contact are burned off from age and use, so you get a distinct "click"' but no starter.

Ignition switch is bad, or the wires are bad between switch and starter. The small purple wire is the one from the switch.

Bad neutral safety switch, or missing bushing(s) in the shifter linkage. If the switch isn't in Park or Neutral position, the starter isn't connected to the key switch.... Try shifting to neutral, and/or wriggling the shift lever. Switch isn't too bad to replace -- it's on the transmission around the shift lever.

Bad neutral safety switch is the most likely, and missing bushings are probably second choice.

No start hot (with engine cranking) can be either ignition failure (no spark) or low fuel pressure due to a failed accumulator or pressure regulator -- ignition is more likely. Best bet is a tuneup -- new points, check wires, resistance in coil, etc. If any major parts are bad, I'd replace the breakerpoint system with a Crane or Pertronix optical unit with new coil and transistor unit. This is much cheaper than the MB parts, and the points won't burn up any more....!

Peter

skalie · #10 12-14-2002, 02:59 PM

Quote:

Originally posted by Tomguy
He said he changed it :p

No, he said he charged it, subtle, but important difference.

Tomguy · #11 12-14-2002, 04:50 PM

Ah, my bad :p

The neutral safety switch sounds like a likely cause

awarne · #12 12-15-2002, 05:40 AM

sorry fellas the batt is a brand new gel cell so i know its not the battery. no click noise even. probably the neutral switch, where is it ? anyone know
Thanks again

awarne · #13 12-15-2002, 05:43 AM

aaah! psfred already told me where thanks.

awarne · #14 12-15-2002, 06:28 AM

Thanks for all your guys help. couldnt have figured it out without by myself.

Aaron · #15 12-15-2002, 04:21 PM

Psfred,

Agree totally with you. I just mentioned vapor lock before we had anymore info on the symptoms. I was under the impression that it would crank but not fire. I didn't know it wouldn't even crank..