Before I do something stupid, can anyone tell me how high the radiator overflow pipe should "stick up" inside the filler neck? When I remove the radiator cap, the overflow pipe is actually 1/4" HIGHER than the top of the filler neck. It seems to me that as the water warms, and expands, it needs to actually raise above the level of the filler neck before the excess passes through the overflow tube. This situation then places the motometer in the hot water, instead of "measuring the steam above the water"
So it seems to me that I should cut the overflow pipe so it's about 1/4" BELOW the level of the filler neck so it will drain excess water. Am I correct on this?
Also, how would one go about cutting this down to size? Is there an "end-cutting" type tool?
I appreciate any advice or help here.
My tube sticks up about the same as yours, Don.
If it were mine, I'd cut it to below the level that the gasket sits at. Even with a gasket, that's asking for leaks and dribbles.
The top of the overflow pipe on my '24's replacement flat tube radiator sits a little below the filler neck gasket.
If yours is too high, maybe try lightly stuffing a rag into the filler neck to catch the chips (leave one corner of the rag sticking out so that you can pull the rag and chips back out) and use a Dremel tool with a cutting wheel to cut off the excess tubing. Be careful not to cut into the radiator neck!
Jerry; I was thinking about 1/4" below the level to avoid leaks.
Don..do you have a motometer? Does the instrument dip into the hot water on your car? I always thought that was a "no-no" so I was thinking using the depth of the motometer as a guide for the overflow tube.
Thanks guys! Appreciate the help!!
That's where I would cut it.
The overflow on my original '14 radiator is just about even with the bottom of the filler neck where it meets the top tank. I don't think they were that fussy about the height but regardless I have found that all my T's spit out what they don't want and then settle down at their own level. The height of the overflow tube doesn't seem to have an effect one way or the other.
Mine is about 1/8" below radiator cap gasket
Oops but then I put it in
My Brassworks radiator has it about the level of the bottom of the filler neck. I have thought of adding an extension tube to raise it. When braking hard quite a bit of water is lost out the O/F I think and lowers the working level although no overheating.
Of course I have Fourwheel / Big Four and Bennett rear brakes.
Im trying to get a consensus so it will not lose too much water, but also not rise higher than the filler neck before it drains out the overflow. Mine is 1/4" above the neck so the water has to raise above that level before it drains. just asking for leaks and a lot of misreadings from the motometer.
The overflow tube is just below the bottom of the radiator cap. That has nothing to do with water level in the radiator, which will settle about 1 - 2" above the fins in the radiator when cold. Any coolant above that level will get pushed out the overflow when the coolant is hot.