[ehawk01]

This board has helped me resurrect a 1983 380SL from the dead. While I still have quite a few issues to fix, it runs. Driving it around this summer has been the motivation to continue to knock out her issues. I have noticed an oil leak coming from the passenger side of the engine somewhere above the oil filter. It is difficult to see in there from above and below the car. I thought it may be the oil pressure sender or oil temp sensor. Last night I was looking and feeling around trying to confirm my suspicions and I located something oily near the exhaust manifold that I do not know what it is. Everything that is oily is below it, so I thought it may be the culprit. Can someone look at the picture and tell me what this is?

 

[rowdie]

I am guessing but it looks like the timing chain tensioner.

 

[ehawk01]

I thought it might be, but I have not had a need to use that yet.

Is that something that would typically leak oil and if so how would I seal it up?

 

[rowdie]

I thought it might be, but I have not had a need to use that yet.

Is that something that would typically leak oil and if so how would I seal it up?

I don't understand "I have not had a need to use that yet." It is constantly in use. Not common for it to leak. Could be the seal.

 

[ehawk01]

I don't understand "I have not had a need to use that yet." It is constantly in use. Not common for it to leak. Could be the seal.

ok. I will look into the seal.

 

[ehawk01]

I have not had a need to replace that part yet. Is it difficult to replace the gasket?

 

[PanzerPuff]

I have not had a need to replace that part yet. Is it difficult to replace the gasket?

http://www.benzworld.org/forums/r-c...lopaedia-germanica-volume-107-aka-egv107.html

http://www.benzworld.org/forums/r-c...stallation-380-sl-timing-chain-tensioner.html

 

[ehawk01]

Thanks @ PanzerPuff!

Looks to be moderately involved. I am going to try to avoid messing with it unless I can confirm that the leak is coming from there. I think I may have some spare bolts I got in a variety pack if it comes to that.

Is there anything else in the general area that would spray or leak oil near the tensioner and drip down onto the oil filter housing? I see something with a smaller heater hose connected to it directly across from the tensioner that is also oily. It is hard to tell if it is the culprit or a symptom. I am not sure what it does. I assume it is related to cooling the oil somehow.

I cleaned the area so that I would notice the new oil spots. Then I put some dye into the oil and will check with the special light and glasses before I just pull the tensioner out on a hunch. Crazy thing is I drove it for a few miles and I could not see any dye yet. Trying not to take it for a long drive and have not be able to tell where the leak is starting from. It seems to run down the passenger side of the engine area and then drip all the way back towards the tranny. Makes a nice sticky mess...

 

[PanzerPuff]

Thanks @ PanzerPuff!
Looks to be moderately involved. I am going to try to avoid messing with it unless I can confirm that the leak is coming from there. I think I may have some spare bolts I got in a variety pack if it comes to that.

Replacing the tensioner is the subject of those links. I think if you just tightened the two tensioner screws it might make a difference in the leak rate, if indeed that is the spot. Shop manual page 05-310 recommends 25 Nm torque. You could also check the torque on the valve covers but take care not to go much over 3 newton-meters on those copper crush washers.

 

[rowdie]

I see something with a smaller heater hose connected to it directly across from the tensioner that is also oily. It is hard to tell if it is the culprit or a symptom. I am not sure what it does. I assume it is related to cooling the oil somehow.

There is nothing involving engine oil cooling externally on your model. Unless someone installed an after market part or your's is not a North American model.

 

[ehawk01]

@rowdie I doubt there is anything aftermarket installed there. So that might help confirm the tensioner leak. @PanzerPuff I will try tightening the bolts on the tensioner and see if that fixes it.

Thanks a lot guys!

 

[Ken Childers]

Rather than start a new thread, I hope it is permissible to asked a somewhat related question about an oil leak on a different engine.


My rather small leak on a M110.990 engine is on the passenger sie around the head gasket. The question concerns the advisabililty of using "Lucas Stop Engine Oil Leak". I've never had occasion to use any Lucas items previously but have been told they manufacture good, reliable, safe products. While the Lucas recommended mixture is 20% of the crankcase capacity, I have successfully stopped the leak with an 85/15 percent mixture. Any comments re the use of Lucas Oil Stop leak?

 

[ehawk01]

Is this your daily driver or just a project car?

I think that Lucas products can help "kick the can down the road" and give you some time before you have to fix the "real" problem. I used some Lucas (plus a fluid and filter change) in my R107 tranny last year and it has eliminated the slipping ever since. It is not my daily driver though...

 

[Ken Childers]

No, it is anything but a daily driver. Leak has been present since purchasing the car in Germany in 1986 - just had gotten a little worse over the last few years. I've always been told this engine is prone to have this problem around the had gasket.

 

[sublettm1]

This thread has sparked some interest by me. I too have had an oil leak on the passenger side of the car for a couple years now. I thought it was leaking around the oil filter housing but the leak was still there after the last oil change where I made sure to replace all o-rings and crush washers. Now I'm thinking I may have a leak around the timing chain tensioner. From what I can tell this is just above the oil filter housing. Is there the possibility that the tensioner is just a little loose? I guess if the seal is bad I would be better off replacing the tensioner and gasket since I will already be in there. Hadn't considered the tensioner as the problem.

 

[ehawk01]

@sublettm1 I think my car is leaking from the same place. Trying UV dye in the crankcase to try and confirm.

 

[rowdie]

Just a thought. The oil pressure sender is just below the tensioner. The valve cover is the most likely culprit.

 

[ehawk01]

I looked around a bit more last night and it seems that the oil is coming from the bottom of tensioner. The valve cover seems nice and dry. I tried to tighten the bolts, but they were already very tight.

Is the gasket the only thing that prevents the tensioner for leaking? I have seen some tensioners that have an O ring too.

I just had the chain upgraded to the dual row last year, but everything else seems to be working just fine. I think it is the original tensioner though...Should I replace the gasket only or the whole tensioner while I am at it?