besel53

Gonna put a new radiator in my buddies 95 this weekend. It's blown 2 cheap radiators over the last 3 years, so somehow it's either building too much pressure or getting clogged and blowing a hole in the seam between the plastic tank and the core. We're going to put in a 2 core all aluminum this time, but I hope it doesn't get wrecked. Of course we're going to flush the crap out of it again, but how do I know if the water pump is doing a good job, and would it cause ?

lewissa81

The water pump can't build too much pressure by itself. If you are in doubt of it though, just replace it. They're cheap enough. Replace the thermostat while you're at it too.
The problem is probably installing CHEAP radiators. There's a reason they're cheap.

besel53

Well, decided not to do the water pump. Thermostat was recently replaced as well. Put a flush kit in the heater hose, and flushed the crap out of it, filled 4 five gallon pails before it ran clear. Put a new 2 row all-aluminum radiator in it with a new cap as well. Filled up, and checked it all out while doing front brakes, and an oil change. Back on track for this '95.

I had one question....below the fill hole/cap, there are two overflow tubes. One is below the bottom seal on the cap, and the other is in between the top seal and the bottom seal. Which one do I connect the overflow tank to? The previous POS radiator had the top tube connected, but I put the overflow on the bottom on this one because it made more sense, because any +/- pressure would just push/pull from the tank. Is that right?

techrep

iTrader: (1)

the over flow should be on the recovery tank ??

besel53

yes, but there are two outlets from the radiator, up by the cap. One outlet you cap, the other goes to the recovery/overflow tank. The question is which outlet, top or bottom to the tank?

besel53

This is a pic of a different radiator, but there are two outlets up top by the cap. Which one goes to the tank?

lewissa81

The only time I've seen that type of set up (that I can remember), both went to the overflow tank. The top tube is incase the pressure exceeds the cap, or the cap fails. For now, I think you would be safe connecting the bottom outlet to the overflow. Secure a tube from the top to the bottom of the radiator as a type of vent incase the engine gets to hot and the pressure overcomes the cap. Does that make sense?

techrep

iTrader: (1)

don't matter which one you use...cap one use the other...are they both below the cap ?

besel53

The rad came with a rubber cap with hose clamp for one of them, which I put on the top one, the bottom one is going to the tank, but I do think you are right on this, thanks.

besel53

I don't think that's quite correct, the radiator cap has two seals, one is at the bottom, which compresses against the narrow part in the neck, and the other seal is at the top of the cap sealing the top. The bottom overflow outlet is below both seals, the top outlet is in between the seals...presumably to let out overflow if the pressure exceeds the bottom seal. Thanks though.