burping

[gudtimer41]

No it's not a problem with acid indigestion or 'gas'. I changed all the clamps on my cooling system, removing the hoses. Filled 'er back up and the cooling fan won't turn on when it should. The switch is new, grounds are good, fuses are good and the motor turns on when shorted. The bottom of the radiator does not get hot when the engine does, so I assume an air bubble is lurking somewhere, blocking off the switch. How do you go about removing air from the cooling system so that things get back to normal? As 'normal' as Spiders get, that is? thanks, Ed

[narfire]

Some will instal a "T" on the heater hose coming from the firewall.
I have had one on the shelf for a couple of years and just have not got around to installing the thing.

To burp I jack the front end up or use ramps, perhaps even doing that on the slope of the driveway. Take the rad cap off and run the car untill the burping has stopped and you see the coolant flowing in the rad. When it is flowing the stat is open and the system is doing what its supposed to. Turn the car off and top up the rad.
This can take ten or more minutes of idling to get the air out, but again you should see the coolant flowing. The temp gauge should be reading around 190 deg when the fan kicks on.
Chris

[RRoller123]

There are a few ways to do this, but I will comment even though I am no expert because I had the EXACT same problem until just recently. The fan would not come on no matter what and my gauges were wacky. So here is the process that worked for me: (I will editorialize a little because I had a hose blow halfway through and had to repair it and start over)

(car on level ground. engine off and completely cold)
1.) Drain and flush radiator and block.
1a.) (In my case I also replaced the two temp gauges senders in the top of the head)
2.) Remove (4) main hoses, check for weak ones and replace.
3.) Drill 1/8" hole in t-stat plate. Clean out the resultant filings. (Actually just verified it was there, PO did it).
4.) Test T-Stat on stove in pan of water with plumber's thermometer.
5.) Remove Fan Temp Sensor from radiator bottom and test it.
6.) Put it all back together.
7.) Fill radiator. Put the cap on.
8.) Disconnect hose from front of engine (the one that runs down to the T-Stat) and fill from there until it runs out the front. (The drilled hole lets it fill well). Hook it back up.
9.) Disconnect the throttle plate heater hose and fill through the hose until it starts to run out through the throttle plate heater. Hook it back up.
10.) Jack up the front end until the bleeder plug at the front union is the highest point, and pull the plug.
11.) Fill through the plug until it is full and starts to overflow. Put it all back together, check for tight clamps.
12.) Lower the car, start it up, check for leaks and see that it makes a few cycles. Took 10-15 minutes to get up to fan running temp.

It has been perfect ever since. Without the sensor testing it doesn't take very long at all.

[DaveT]

I used the Prestone 'T' fitting on the heater hose. Drained radiator & block and just filled it up entirely from the tee. Worked well.

[4uall]

I have never needed to jack my Fiona up by using this procedure

http://forum.fiatspider.com/f08/viewtop ... on#p126761

[gudtimer41]

Thanks to one and all for your replies. I'm going to try the simple way first. I'll jack up the front end, run the engine and wait until the air bubbles stop. As Arnold says: I'll be back!

[JammerX19]

I have never had to resort to any bizarre rituals to get my Spider's cooling system burped. I just installed the Prestone flush T and then followed the service manual directions to burp the car, then top it off at the T. On the FI car, the procedure is:

1. Fill radiator and cap it.
2. Pull the hose off the thermostat T (pass. side of car) and pour coolant into it slowly until it starts to pour out of T.
3. Put the hose back on, then remove the 19mm plug on the thermostat T.
4. Pour coolant into thermostat T with a very small funnel until it overflows.
5. Run car for a minute with the heater valve open. Then shut off and top off the flush T.

Done this three times on my car (hoses replaced last year, radiator this year, for GPs the year before that) and never had any trouble.

[RRoller123]

On the FI cars you need to fill (bleed) the Throttle Plate Heater too. There is air in there when the system is drained.

[4uall]

you know what's funny? I do not have one on my FI


IMG_0746 by itzebtze, on Flickr

[JammerX19]

you know what's funny? I do not have one on my FI


IMG_0746 by itzebtze, on Flickr

I removed mine. I suspect a lot of folks do. They're a pain in the butt.

[RRoller123]

That is very interesting! Why are they a pain in the butt? Mine doesn't leak, is it something else?

[JammerX19]

That is very interesting! Why are they a pain in the butt? Mine doesn't leak, is it something else?

My car is an '80 and appears to have the first generation FI system on it, which includes a one-piece brass unit that bolts to the top of the FI plenum. It had been removed by the PO when I bought the car and was replaced with a hollow tube to connect the two hoses. I tried to find two replacement brass boxes for the car and both leaked on arrival. So when the time came to replace all the heater hoses, I also replaced the metal water pipe that runs from the water pump to the inlet for the interior cabin heater. The FI car's heater pipe has a nipple on it for this FI heater but the early style does not. Fits perfectly and eliminates that unnecessary heater circuit (I don't drive my car in cold weather).

[RRoller123]

That is interesting. I am still confused as to the purpose of this thing. In cold weather, why does the throttle need to be heated anyway?

[JammerX19]

That is interesting. I am still confused as to the purpose of this thing. In cold weather, why does the throttle need to be heated anyway?

Couldn't say. In prop-driven aircraft, there's a carburetor heat function that keeps the carb from icing up, I'd say this does something similar, heating the air enough that the system won't freeze up. That's my only guess.

[narfire]

In cold weather, why does the throttle need to be heated anyway?

In or on the cold days the air flowing over the "throttle butterfly" in the intake can deposit moisture and ice will develop. The heater on top is supposed to prevent that.
As mentioned, I can't see it being an issue in the warmer climates, but perhaps hold onto it if one were to sell the car and it goes north.