VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 water temperature

I have a 1926 chev car , when operating in shop for 15 minutes or more checking temperature with radiator cap off it is operating at 180 to 190 , with some mild foaming. When shut of temp jumps to 200+ and pukes water, is this a cause for concern. thanks for the comments

You have two problems. One: The cooling capacity is compromised. Probably some of the passages in the radiator are plugged or flow restricted. Also could be the water pump is not circulating as much water as it should. Second: The water pump is sucking air past the packing on the shaft.

Depends on how high the water level in the radiator top tank is, if it's less than a couple of inches from the overflow pipe when running, then water will always be puked out when the fan and pump stop turning, because due to lack of movement and airflow heat builds up and expands the water.

This will happen even with a perfectly maintained system, not a concern, just adjust the water level.

The foaming is another matter, it could be a number of things, antifreeze will cause foaming in an un pressurised system. as will a leaky head gasket, or as Chipper says pump packing loose..

thanks for the information, the radiator core is new so hope that is not the problem: how tight should the water pump packing grease cup be turned in and what should the proper operating temp be?

It isn't the grease cup it is the large packing nut surrounding the shaft that screws into the pump. You want it snug but not to tight as to cause a heat buildup.

Dave

Here is a picture of my 24 owners manual showing the nut and instructions. I suspect your 26 would be similar but I am not positive.