Help! I dropped it down the...
 

While removing the thermostat from my 91 300e, the little round ball/valve fell out & down into the antifreeze in the housing. I will try to suction antifreeze out and then try to find & get the valve out using a magnetic tool. If I can't find it, can I drain it out? I have just "restored" the front end following an accident & I am afraid if I drive the car without getting this thing out I will ruin the engine. I hope MB anticipated something could fall down there and made retrieval easy. Thanks.

richard28,

You might have luck with a magnetic tool as the housing is probably aluminum and if it went down a hose it should be retrievable with a magnetic tool too. Not sure how effective a magnet will be if it went into the ferromagnetic head or the block. I am assuming this is a car with a cast iron head.

But, while I would not recommend the coolant system as a place to deposit these kinds of things, I suspect the net effect of having this part in the system will be neglible. So, if you don't find it, I would not sweat it too much. It might affect the pump a wee bit the first time through, but after that it will find a low flow spot and hang there until something comes to get it out. Coolant systems run with lots of scale and other debris deposited here and there. Your little steely is not going to really do much.

Good luck, Jim

Thanks, Jim., for the comfort. I was also afraid it could clog the heating core.
Rich