Bricksters,
It seems to me that after buying a nice three row radiator, a quality water pump,etc...that there is still something very lacking. A decent expansion tank. These cheap plastic bottles have got to go! If there was a METAL resevior, it could be repaired. Any ideas on a "tank" that could be modified to do the job? The hose nipples would be easy. Adding a cap would be the biggest challenge. Think it over and post an idea or suggestion.


mark

Believe it or not, the ONLY time when those plastic tanks will ever give the owner any trouble is when the driver hits something with the front of the radiator, like a high cement stopping block, high curb or ice bank in the winter. The radiator hangs low and many people are unaware just how volnerable it is to damage like that and if hit hard enough, one of the side tank ears will break off usually causing a coolant leak and requiring a new radiator. Even if the radiator had copper or aluminum side tanks, it too would also not likely survive the same accident w/o leaking if that's even a consideration. The plastic tanks cause no problems in themselves if never hit and those are very good radiators usually lasting about 200K miles, give or take a few.

Mark, the reason for plastic radiator tanks is safety as well as economy. The fluid level can be checked without removing the cap. When someone removes a coolant cap when the system is under pressure, coolant or presure is expelled, if the temperature of the coolant is above its boiling temperature, a BLEVE (pronounced blevy)can occur.

When a BLEVE (boiling liquid expanding vapor explosion) occurs in a cooling system some of the coolant instantly flashes to a vapor (steam)and liquid is blown out the cap. This expansion is is a factor of hundreds, most expansion tanks could never accomodate it. Usually the hottest liquid in a cooling system is in the cylinder head, this flashes to steam and pushes all the liquid ahead of it out through the outlet. The lucky people usually get burms on their backs if they turn around fast enough, the unlucky ones get much worse. I have seen coolant that was blown 20 feet in the air and wet the top of a small tree.

We have a Freightliner fire engine that has a sight glass to check coolant level, the men who have to do mechanical checks still remove the cap because they do not trust the sight glass.

I'll bet that the parts and manufacturing costs to add a sight glass are greater than those of a whole plastic expansion tank.

Ask any women drivers that you know if they would remove an expansion tank cap to check coolant level. many drivers never check their fluid levels, or even tires for that matter.

If you really want a metal expansion tank, go to a truck dealer, or a truck salvage yard, I'm sure you can find one with a sight glass and a standard neck for a pressure cap. I'm quite sure that you might even find a Volvo tank!
--
2 8s & 2 7s 600,000 miles total

I used to feel the hoss on my old mustang

(I'd check the level cold, but not hot, and I would open it and leave it open to verify the t-stat opened)