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Discussion Starter #1
my uncle gave me 1990 300E
He told my dad that the car overheated.
Car will no start!!!
I crank the car and it seem like there is no compression
is this a commom problem????
Pls Help
 

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drg

Help us help you. Fill out your profile, tell us about the car other than it being a 1990 300E. How many miles etc. etc. Collectively, there is a ton of experience on the forum but I assure you none of us has graduated from crystal ball reading school.

Good Luck and welcome

Jayare
 

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These engines have plenty good compression even beyond 250k miles. I know of a 300E that have made it to 325k miles still runs...barely. If the car overheated previously and you have no compression, I think it may be time for a head gasket. If the car was running with a bad head gasket for a while, check around for oil leaks in that area of the engine. Now would also be a good time to find out what went wrong with the cooling system in the car. My $.02
 

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Are you sure its bad compression? Did you do a compression test?

The proper way to go about it is to first do the compression test. If you have low compression in any 1 cylinder then do a leakdown test to see if the number goes up. If it does then your piston rings aren't sealing.

Head gasket damage manifests itself on these cars in very distinct ways. You will know if you have head gasket damage if:

1. You see "chocolate milk" in the coolant expansion tank. This is probably one of the most common failure modes for the headgasket. A bypass between the coolant channel and oil channel.

2. Mayonnaise-like substance under the oil cap

3. Oil weeping at the parting line of the head and engine block

4. White smoke on startup and/or acceleration.

5. The cooling system will not hold pressure (+20 psi) and you aren't losing any coolant. (In this case combustion gases are getting into your cooling system and your expansion tank cap will be working overtime to evacuate the excess pressure).

You can try a can of Bar's Leak Heavy Duty Radiator Stop Leak to see if it makes any difference.

Personally, I think you just need new rotor/cap, wires, and plugs. I remember reading somewhere that the Bosch ignition coils that Mercedes used in the earlier 300e (pre-1990) were prone to vibration damage. A new one will cost $70. Something to look into. Also, the CPS (crankshaft position sensor) is needed to start the car and these have a habit of going bad with time. Cheap fix too. Tweaking the fuel distributor pressure will also do wonders for the responsiveness.
 
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