I have a thermostat, and cable/fan. That is it. My engine bay pump is hooked up to open air and it never turns on........


I have searched google, type IV secrets revealed and this forum as well as others. I can't find the pictures I need or info I need on when/how the air pump in the bay is activated.

I'm trying to not blow up my good condition 1800 fuelie, and I get the feeling with the hot muggy weather coming back here a working cooling systme is probably A1 before I start driving it semi regularly.

Does anyone have any photos? Tips/hints?


From what I was told the pump just evacuates the engine bay air below the tin so it is not recycled back through by the cooling fan and back over the heads?



I suck at air cooled cars.

Never heard of that. The only air pump I'm familiar with is a smog device. I was happy to toss mine.

Ok I am crazy then? All these cars have is the cooling fan on the crank, thermostat with wire, pulley and spring etc.?

THat is it?

I thought that the engine bay had an airpump to pump the air out or something?

Are you talking about the motor/squirrel cage fan in the eng. compatment? If so, that is part of the heater system. Later models had a smog pump....is that what you see?????

Are you talking about the heater fan that has 2 hoses going through the cooling shroud to the heat exchangers?

The engine is cooled by air being pushed by a fan through the engine tin. The thermostat (bellows) operates a par of flaps that close off the tin from the fan air to let the engine heat up faster.

Thats it. Thats the cooling system. So long as you have all your tin, and you have the fan working and your flaps are not perminantly closed, you are working with a good cooling system.

Zach

Ahh ok, it mounts on the side opposite hell hole, by the chassis ground point there on a curved bracket?

I have a 75 1.8l california car. Any EGR/cat has been removed by the previous owner.

I am pretty much eliminating the heat from my 914. Warm weather/sunny day only car.

Or bundle up. More weight, complexity etc. I do not want to deal with it or really need it. I'm missing a bunch of pieces already, and I apparently have 1.7l headers with no heat exchangers.

But that is it for the cooling system? I was reading on another forum that hinted at more and in the future a section of type IV secrets revealed dedicated to the cooling system.

If that is it, I will actually drive it. I'm just fearful of blowing this thing up since I can't waltz down to a pick and pull for a Type IV motor, heads etc.

I don't know if you're talking about the electric powered heater blower fan, or the belt driven air pump. I had assumed the latter before. If you remove the smog pump you have to plug the holes where it injected into the engine.

Either way, it's not part of the cooling system. There's no pump that evacuates engine bay air. Cooling system is just the fan on the front of the motor and engine tin. Thermostat helps engine warm up quicker.

The EGR pump is removed, and it's input into the intake stream has been plugged. I also did away with the decel vacuum valve thing as well.

I guess that would be the electric heater blower fan... I just thought that was under the front, btu I guess you would need a blower to push the heat all the way through the heater tubes/rockers up there....

I was confused from reading the tidbits here/there between forums.

If it is as simple as the vacca rabbite says, then I will be golden after I adjust the thermostat cable tension and make sure the pulley is ok.

Thanks guys.

Make sure that the flaps inside the fan shroud work right. They are supposed to fail open. Mine failed closed.

I took the bellows off the engine and static set the flaps open. I don't trust them. my car won't drive in the winter, so I am not to worried about really cold starts and long warm up times.

Zach

The fan in the front you are thinking about is for fresh air. The fan in the eng. compartment is to "push" hot air for heat.....If you're not going to use the heat...then you can remove it.

I think I may just do this, if I can't get it proper. Insurance it will not overheat.

The cable has already fallen off the pulley twice now.....

...then you need to tighten the nut that clamps the cable with the cooling flaps under tension. I am having a hard time figuring out how to explain this but if your cable is coming off the wheel, then the thermostat is loosening the cable so that is why it's coming off the wheel. Did you do this;

Without touching the shaft that the flaps are mounted to, observe that there is a spring on the shaft near where the cable will be clamped. If you push down on the place near the spring, the little piece that juts out from the shaft, you should be able to push down on that piece and rotate the shaft against the spring pressure. The shaft rotates about 50ish degrees (?). You have to rotate the shaft against the spring pressure, then clamp the cable tight. The thermostat works in such a way as to relax the spring pressure on the shaft as the thermostat heats up. As it heats up, the cooling flaps shaft adjusts to the warm engine cooling mode. When you shut off the engine and it cools down, the contracting thermostat adjusts the flaps to the cold engine/warm-up position.

The thermostat contracts and slacks when hot?

I think I get it, it will become clear if I screw around with it. One of those things that takes 11,000 words to describe but picturing it in action is simple.

For now I may just keep the flaps open in order to just get it going and make sure it will not overheat or fail. Then revisit making it work proper.

thermostat expands and slacks the cable when hot, contracts when cold and pulls the cable. So the thermostat, under heat from the engine, expands, thus slacking the cable and allowing the flaps to come to the position so that it is the correct position for hot engine cooling. That's why, what Zach said, if the cable breaks, the flaps go to the default hot engine position. When the thermostat cools, it contracts and tightens the cable, pulling the flaps against the spring tension to the cold engine position.