Radiator overflow goes to???

[RootesRacer]

What is the radiator overflow supposed to dump into?

I have an early expansion tank on my SII, which has a normal overflow port on it.

Newer cars have this going to a tank, and the engine can suck coolant back to the engine when it cools.

The SII cap doesnt seem to have a seal on the top part of the cap, so I would imagine it was not intended to be a "closed" system.

Anyone have any info?

I kinda hate to dump perfectly good coolant on the ground.

 

[puff4]

It goes to a thin-walled, non-reinforced rubber tube which then goes down the left side of the radiator and dumps out near the bottom of the radiator. If you look carefully there may still be clips for it on your radiator's frame.

There is no expansion tank or catch tank. If you want a catch tank, you'll have to craft one, because Series Alpines, to my knowledge, never came with one.

 

[65beam]

radiator overflow

i also use a pressure cap on my early models .

 

[serIIalpine]

If you are from where I live it goes into the Santa Monica Bay.

That's why I have a 1qt gatorade bottle wedged into the right corner of my engine compartment.

I cut a hole just big enough for the rubber hose to fit and it seems to work just fine. It actually sucks the coolant back into the expansion tank on the few occasions it has gotten hot enough to force any coolant out.

I need to find a catch tank that has a internal tube that reaches all the way to the bottom of the tank for this little maneuver to work.

Eric

'62 SerII

 

[alpine_64]

What is the radiator overflow supposed to dump into?

I have an early expansion tank on my SII, which has a normal overflow port on it.

Newer cars have this going to a tank, and the engine can suck coolant back to the engine when it cools.

The SII cap doesnt seem to have a seal on the top part of the cap, so I would imagine it was not intended to be a "closed" system.

Anyone have any info?

I kinda hate to dump perfectly good coolant on the ground.

jarrid

Kevin is correct, there is no recovery system on alpines. The early cars have a habbit of puking in traffic. Get a windscreen washer bottle, cut a hole for your expansion tube and buy a return cap for your radiator (can be a bit tricky due to depth) here is a link that should show you mine:
click for a bigger image

 

[steven]

When I received my first wreck, it had the overflow unit from a mini fitted. It is a metal unit with its own pressure cap and fits neatly in a corner next to the radiator. Maybe they are a rare item themselves now. Oh the wreck is now finished and the little overflow is still in use.
Steven

 

[Andrew]

I used an extra windscreen washer bottle holder and an extra Rootes washer bottle. I then thought about how hot the coolant may get and removed the washer bottle in fear that it would metl. I then installed an alum. water bottle, cut the ring off the top cap and drilled a hole for the hose. It is nice to be able recover the radiator coolant. You will need to use the correct radiator cap in order to do this.

Regards,
Andrew

 

[AlpineII]

I also went out and bought a new windshield washer bottle and install it on the left side, beside the rad. Works well and I have yet to have it melt!

 

[chris]

Does the overflow tank on Tigers allow the fluid to return to the radiator?

 

[puff4]

Does the overflow tank on Tigers allow the fluid to return to the radiator?

It's been a while since I owned a Tiger, but IIRC the tank is a pressure tank, not an overflow tank, and the over-flow from the radiator cap on the pressure tank vents the same way as an Alpine - right onto the ground. And come to think of it, with mine that was pretty often!

 

[Ken Ellis]

Can you folks post the "return cap" part numbers/sources, please?
And whether you have short or long-necked radiators?

Thanks,
Ken

 

[hillmanhuskyguy]

Can you folks post the "return cap" part numbers/sources, please?
And whether you have short or long-necked radiators?

Thanks,
Ken

+1 on posting the p/n's for this cap. My overflow tuibe drips down into an old glass soda bottle. I've only driven the car twice now but it seems to overflow that and then it hits the ground.

Cris

 

[Alpineracer8]

It's been a while since I owned a Tiger, but IIRC the tank is a pressure tank, not an overflow tank, and the over-flow from the radiator cap on the pressure tank vents the same way as an Alpine - right onto the ground. And come to think of it, with mine that was pretty often!

You're right, Kevin. The header tank on a Tiger is not an overflow tank. It, too, has an overflow tube that goes to the ground.

 

[phatt]

I use the coolant recovery tank from a 72 MG Midget. I found it in a wrecking yard. To work effectively, the pressure cap should be on the catch tank. The cap on the radiator needs to have a cap that does not have any pressure release built into it. It is simply there to keep the coolant from escaping from the radiator. I am currently using a pressure cap with holes drilled into the stopper to let the coolant flow freely from the radiator to the catch tank. Yesterday I ordered a cap from a late model Datsun roadster. I'll let everyone know if it fits correctly. By the way, the plastic radiator fan from the same model roadster is a straight bolt on to the Alpine. I believe it has 7 blades and moves a ton of air. The downside is that the fan is very noisy under acceleration. It makes the car sound like it has a turbo. Paul Hatter

 

[bobw]

Pressure caps will allow fluid to be sucked back into the radiator as the coolant cools. I found this drawing of an example on the web. The plastic container isn't designed to hold pressure, just the excess coolant. There is still an overflow tube from the overflow bottle, but it will only come into play if there is catastrophic overheating. There may be some systems set up with a pressurized overflow bottle, but most are not.

Bob W.

 

[puff4]

Correct, Bob. If you look at the pressure cap for systems that have a plastic (non-pressurized) recovery bottle you'll see that the cap has a brass return valve on the bottom, and this allows the fluid to be sucked back in from the reservoir.

 

[RootesRacer]

Correct, Bob. If you look at the pressure cap for systems that have a plastic (non-pressurized) recovery bottle you'll see that the cap has a brass return valve on the bottom, and this allows the fluid to be sucked back in from the reservoir.

Another not so obvious requirement is that the top of the cap also needs a seal.

The earlier caps (SI-SII with header tank without separate relief valve) lack a seal on the top of the cap, which prevents a vacuum from forming and sucking fluid back into the tank. In fact, the return valve also is missing from these caps so its a double fail.

I would really appreciate if anyone has a proper application for a full closed cooling system rad cap for the early tank.

 

[phatt]

The catch tank I used from the MG is metal not plastic. The system used on the late model Datsun roadsters also has a metal tank. The pressure cap is on the catch tank and the cap has a button on the top so the pressure can be released from that point. Any coolant drawn into the catch tank is returned to the radiator as the system cools thus keeping the radiator completely full of coolant. Paul Hatter

 

[Andrew]

Pressure caps will allow fluid to be sucked back into the radiator as the coolant cools.

Right on Bob, that is why I said the correct cap. I originally used a plastic washer bottle and found that it would get a little soft when the engine was good and hot, I was worried about a melt down. A Rootes washer bottle looks good but I don't think the plastic is the best for the job. I would use a correct collant container as shown by Bob or find a metal container that can do the job for you. The important thing is the cap.

Andrew

 

[V6 JOSE]

My Turbo Alpine, uses an overflow bottle from an old Volvo. It works great, because the dovetail frame that the bottle slips into, was removed from the Volvo radiator and soldered onto the driver´s side of the Alpine radiator frame. The bottle is made of a heavy plastic, so it is easy to see the fluid level. The bottle can be removed easily, by just lifting it out of it´s holder, and it fits comfortably beside the radiator, because it is a long bottle, that is about 2" in diameter.

Jose