Radiator plug problem

1988............740 Volvo Estate.


My son is away with the above car, he has had the plug for the temperature
gauge for the electric fan pop out and cause the engine to over heat. The
engine does not have an electric fan it is pulley driven so.
The radiator has been temporarily repaired at the roadside by the roadside
recovery service ( RAC ) in the U.K.
How do I replace the plug that has popped out.

 

I replaced a radiator on my (ex) 740 a couple of years ago and re fitted the
temperature sensor with a new grommet and remember thinking "this thing
could pop out". Not happy with just leaving it as it was, I made a two
pronged clamp that conveniently bolted to some lugs moulded into the plastic
top tank of the radiator. I didn't worry after that!

Regards
Barry

 

Get a new seal (and plug if it was lost) and install like normal. The
plug has a slotted top, position it so that you can wrap a long plastic
tie through the slot and around the tank to hold it in.

Anybody else with this rad design, I'd suggest doing this before that
plug (or temp sensor) pops out on you!

--
Mike F.
Thornhill (near Toronto), Ont.

NOTE: new address!!
Replace tt with t and remove parentheses to email me directly.

 

What would cause the plug to go other than the plug itself.
Could there be a fault in the rad or engine

 

The plug is not the problem, the seal is. There's nothing but friction
of the seal holding the plug in. The pressure inside the rad goes from
0 to 150 kPa (the pressure of the cap) and from freezing cold to above
100 degrees C, repeatedly over a period of years. The seal rubber gets
harder, the coolant functions as a lubricant as it slowly creeps its way
out. Then one day, Poof! and you have problems. If the cap is
defective the pressure can get way higher, so it's a good idea to have
the cap checked (or replace it) since you've had this problem.

--
Mike F.
Thornhill (near Toronto), Ont.

NOTE: new address!!
Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)