Good day!

I recently had my other 240 set aside when the HG busted and now my 245 showing similar signs. My temp guage goes up about a needles width past normal and then back to it usual place when being started from cold. That is just what happened before my other car broke down. There's no oil in coolant or coolant in oil either. Other things going on is bubbling sound behind the dash, it revs once or twice at startup and a slight high idle. I was going to change coolant and thermostat but its too cold outside. I guess my question is if it can be anything else then the headgasket, what should I have a look at?

Thanks in advance,

John

Thanks!

Feel a little better now. I have some white smoke coming out but other than that it runs pretty alright and there's no leak on the outside of the engine. I don't think the PO did any maintence the years she had it, thermostat and coolant is probably past best before date. I'll just have to take a bite out of the crappy apple and get that G5 in thats been sitting in my back seat for a month now, the arctic air is coming in Wednesday they say.

John

The upper hose should stay cool to your hand until the thermostat opens and the gauge will respond accordingly.

The bubbling sound behind the dash could be air in the heater core or system. I think it is rare but then that is only from my experience with my personal cars.

The engine coolant might be boiling in the block, just when the thermostat opens. Best thought is that the thermostat is hanging shut. Another thought is, it can get worse!

Just for reference, I like the Whaler Brand all brass thermostats as being best for staying accurate over the long haul. Use to be the standard issue, from Volvo and could be a dollar or two more if you can find them.

I think the last one I got, was from RPR out of S.F. You might have to shop around for them because the profit margin may not be as good.
As for the others, for me that is, those that hang on the display cards in stores can get tossed about. It becomes a scary proposition!

A real bad head gasket or crack head might cause extra pressure right away into the coolant bottle. I would check it right after starting up cold. Removing the cap and holding your hand down or stretch wrap over the bottle opening.

Think of these things as having a nice interrelationship moment. Maybe like, grabbing the cold hose is to a hand shake, on your first blind date! Wondering, if and when things will get better or worse?

Phil

Blown head gaskets can blow between the cylinders, and the car will run really bad, or they will leak coolant into the combustion chamber and show lots of white smoke (steam) in the exhaust, or they will leak externally, like this one.

This is a good indication that the thermostat is opening after the engine warms up to operating temperature. Then the needle falls back slightly as cooler water from the radiator is circulated.
Dan

Many times the gauge moves a bit higher when the thermostat first opens, and then settles at a lower point once the engine is warm. If there are no other symptoms, I wouldn't worry about it. It was quite a dramatic effect on older BMW's for sure - several needle widths spike when first warming up.