1985 280SL(Euro) burning smell

[desert]

When we bring our 85 280SL (euro) 52K miles back from a drive with the AC on we have a burning smell which I'm pretty sure isn't electrical. All fluids are at the right levels, no leaks, and plenty of coolent . It really doesen't have a fuel smell but maybe a burnt fuel smell? I really can't tell where it's coming from but I don't smell it coming from the engine compartment. It goes away after a time with no lingering smell. Any ideas?

[rocky raccoon]

Check for seepage from your valve cover. It may only be present when engine is running and producing oil pressure. A small leak will produce a lot of odor if it drips onto your exhaust manifold. Experience speaking.

[desert]

Thanks Rocky but I figured out where and what the smell is. I ran the car on the road without the AC on for quite a while and there was no smell when I brought it back. Answer: water condensation from the AC is dripping on something hot. This also explains why the smell is unique, something like a leaking radiator smell. Now, why is the condensation water hitting something hot?shouldn't it drip straight down to the ground??

[desert]

Here's a follow up question....Is there a tube or something that diverts the AC condensation water past "hot metal" which is causing the fried hot water smell? If so, where is the tube located?

[RickM]

Could it be a leaking heater core?

[desert]

It only does it when I use the AC so I don't think it's the heater core or it would probably do it all the time. Is there a condensation water tube or something that diverts the water from the "hot metal" ? Since it didn't do it before I suspect that whatever keeps the AC condensation water from hitting hot metal is either broken or missing. Any ideas?

[RadioTek]

How does it smell? If it's a sweet 'maple syrup' type smell, that is antifreeze. It may or may not be the heater core. You _really_ hope not. I was getting that some when the overflow tube from the expansion reservoir disappeared, and the overflow was spitting onto the passenger side catalytic converter, with the burnt odor being sucked into the vent.

[rocky raccoon]

All airconditioners have a tube that diverts condensation to a dump point under the chassis. I am unfamiliar with the specific configuration of your 280SL but the tube will originate at the enclosure for your air conditioner expansion coils and end somewhere under the chassis near the rear of the engine compartment. It is commom for that tube to become dislodged, clogged or rotted, certainly in an old timer like your 280SL. Now a guess; look at the firewall on the passenger side for the expansion coil box (that is where most of them are). If the overflow tube is missing, it could be allowing condensate to drip on your exhaust manifold.

[desert]

Thanks for all the input....I have to get the car on a lift to check it out but I'm betting now that it's the condensation tube...Desert