hi

I recently changed the water pump and thermostat in my B 230k engine,(the water pump was leaking). It all seemed to be fine, but today when i drove of for work, the temp gauge didnt stop at the normal 9 o`clock position, but raised all the way to the red area. I stopped the car, opened the hood and opened slowly the expansion tank and squezed the upper radiator hose(it was cold, meaning no water from the engine) After this, i started the car again, and the temp falled down to normal again, and has been there since.

Could this mean that i`ve messed something up while changing the water pump and thermostat? It seems to me that the thermostat didnt open until I squezed the upper hose, could it be a sticky thermostat?

I has happened only once, but i dont want to worry.

help would be appreciated

Thanks!!

As you just did your water pump and thermo, did you do a complete antifreeze change properly mixed? Or did you top up with a weak solution?

In this weather, if the solution is mainly water (or if you topped up with water and didn't run it to mix well) you may have had some ice form and block the thermo. Engine temp increases until ice melts and allows flow to rad, then temp gauge drops.

If this happens again, your antifreeze may be a bit weak. Pull over, stop car and watch the guage until it drops (ice melts).
--
1980 245 Canadian B21A with SU carb and M46 trans

Anytime you replace the thermostat, be sure the little hole and "jiggle pin" in its outer rim are at the 12:00 position. This hastens the release of trapped air in the head and block as you refill the system with coolant.
--
Bob (81-244GL B21F, 83-244DL B23F, 94-944 B230FD plus grocery-getter Dodge minivan, MGB, and numerous old motorcycles)

When you say "recently," do you mean yesterday?

A common event with the B230F is the need to "burp" the block when it has been drained and refilled, such as when installing a water pump. To burp the engine, you do essentially just what you did.

Once the bubble has been purged from the block the coolant can circulate properly and all is well again.
--
Don Foster (near Cape Cod, MA)

Hello,

I could be that your new thermostat is a dud, or just getting it's bearings. My other thought was an air bubble still in the system. When you get home, let the car cool off for a bit. Then remove the expansion tank cap and run the engine until it's hot. Run the engine at about 2500 rpm for a bit to work out the air. You may have to top things up after, but all should be well as a result.

Happy Bricking!!!
--
Richard - '87 245 DL , '82 242 GLT - Half a million km between them!!!

turn on the heat also...
sometimes the heater core gets a bubble in it
Miguel
--
My First Volvo - stock (for now) '84 244, 230+kmi. Owned it since 9/03