Oil consumtion on 230SL

[69Coupe]

I know I should know how to determine where my oil is being lost, via a wet and dry test !

I should know this, but I cant remeber how to do it !

I suspect the valve guides are worn out of it, I've just replaced the valve stem oil seals but that has merely halved the problem.

Before I decide on an engine out job I'd like to determine what I'm in for !

Any clues ?

 

[Andy]

Hi

While you were replacing the valve seals you should of checked the guides for wear. I agree its more likely to be the valve guides worn out. These were a common repair. But if you decide you want to check the engine before stripping. Then have a cylinder leakage test carried out. NOT COMPRESSION TEST!

Regards

Andy @ www.mercedesservicing.com

 

[69Coupe]

Thanks Andy, I did actually examine the valve/guides for wear. I thought I could detect some sidewyas movement of the valve, it was minimal if there at all, but I guess it only has to be present for it to cause oil consumtion !

Exactly what does a leakdown test consist of ?

 

[Andy]

Hi

A cylinder leakage test consists of a machine which works using compressed air. Basically it charges the cylinder with compressed air and measures the amount it losses. Usually measured as a percentage. You can listen for air loss at the rocker cover, exhasut and at the throttle flap by opening it. That way you can isolate where most of the leakage is going. This is the only absolute way of checking any engine. Compresion tests are only a basic check and does not give you direction as to where the problem may be. As you only know that the compression is down. But a lot of shall we say less experienced people use compression test as the way of finding a problem with a cylinder. But they tend to spin the engine over for a long as it takes to get the highest reading. Which is not the acurate way. You should spin the engine over with the throttle fully opened and the engine should be spun over no more than 5or 6 revolutions. Which should be enough to get highest reading. If you continue, yes you will get a higher reading but it is by no means accurate.


Hope this helps.

Regards

Andy @ www.mercedesservicing.com

 

[69Coupe]

Thank you very much Andy. I will organise to get this test done !