Alfetta Cooling Problem - Page 2

superloaf · #16 (**permalink**) 10-08-2009, 11:38 PM

ok, more drama .... alfetta was running fine and then today it started overheating in the driveway with COLD water shooting straight up out of the overflow cap! so i'm guessing it's a multi tiered problem with a semi clogged radiator and and a sticking thermostat. so a couple of questions:

1) why does IAP list no thermostat for the alfetta but they have one for the spider? isn't it the same engine? how many different thermostats are there for the 2.0 engine?

2) my roommate says that the radiator cap (the one on the actual radiator and NOT the overflow tank) should not be turned all the way until it stops but should be about 1/8th to 1/4th of a turn from full tight. this way the cap can regulate flow to the overflow tank or something like that. any truth to this? i've never heard of any reference to this idea for any car so is there any truth to this?

3) so after a little bit of driving the thermo came unstuck and the car idled and ran at a constant 225 which is quite a bit higher than the 175 from a couple of days ago. what temp should it be at? someone above said 175 but that's awfully cool and when it ran at that temp, i think the thermo actuator wasn't at normal running temp as the idle was consistently high (1700-2000rpm) whereas today when it was at 225, the idle fell way down to less than 1000. anyways, seems like normal temp should be around 200 and a little above, right?

**sidewaysalfa** · #17 (**permalink**) 10-09-2009, 01:28 AM

WOW. If it was mine, I would start taking apart the whole cooling system and have each part checked.
The radiator cap should twist till it stops. Recently I had have the neck replaced by a radiator shop, as the ears on it had become bent so that the cap would keep turning. The neck has a stop so that the cap can only twist on so far.
The cap "opens up" at its pressure limit by its spring, not how tight it is twisted on. Hi pressure, spring collapses and lets hot water out to the overflor tank. Loose cap and water escapes from under the cap.
First remove the T-stat, it is the easiest, just 2 bolts. Put in hot water, with a thermometer to see when it opens. Then get a new one anyway. I looked thru IAP and it seems the 77 sedan shows no T-stat. But several other Alfettas and spiders take the same T stat 4015. Driving around today, getting the car ready for the Wine Tour this weekend, I never saw my temp gauge go over about 180 deg, even with the AC running in slow traffic.
Then the radiator. Have it cleaned. The radiator shop will tell you how clogged up it was.
While you have the radiator out, remove the temperature switch and do the same hot water thing except hook it up to a multimeter for continuity. Watch at what temperature it "turns on" and what temp it "turns off". I remember that it was on about 180, but I'm not sure. Then get a new one anyway.
And since you have it all appart, change all the hoses. And heck, clean the front of the engine compartment while you have access.
That's what I would do/ have done. Good luck.

superloaf · #18 (**permalink**) 10-09-2009, 01:44 AM

Quote:

Originally Posted by sidewaysalfa

WOW. If it was mine, I would start taking apart the whole cooling system and have each part checked.
The radiator cap should twist till it stops. Recently I had have the neck replaced by a radiator shop, as the ears on it had become bent so that the cap would keep turning. The neck has a stop so that the cap can only twist on so far.
The cap "opens up" at its pressure limit by its spring, not how tight it is twisted on. Hi pressure, spring collapses and lets hot water out to the overflor tank. Loose cap and water escapes from under the cap.
First remove the T-stat, it is the easiest, just 2 bolts. Put in hot water, with a thermometer to see when it opens. Then get a new one anyway. I looked thru IAP and it seems the 77 sedan shows no T-stat. But several other Alfettas and spiders take the same T stat 4015. Driving around today, getting the car ready for the Wine Tour this weekend, I never saw my temp gauge go over about 180 deg, even with the AC running in slow traffic.
Then the radiator. Have it cleaned. The radiator shop will tell you how clogged up it was.
While you have the radiator out, remove the temperature switch and do the same hot water thing except hook it up to a multimeter for continuity. Watch at what temperature it "turns on" and what temp it "turns off". I remember that it was on about 180, but I'm not sure. Then get a new one anyway.
And since you have it all appart, change all the hoses. And heck, clean the front of the engine compartment while you have access.
That's what I would do/ have done. Good luck.

superloaf · #19 (**permalink**) 10-09-2009, 03:09 AM

wow, i can't a single thing anywhere (including google) on replacing the alfa thermostat. is it just below the water outlet on the cylinder head? any secrets to know? any problems or unforeseen difficulties? what gaskets are needed?

if anyone can point me to a thread about it, i'd appreciate it.

**La Voce** · #20 (**permalink**) 10-09-2009, 05:37 AM

The top hose on the radiator runs to the thermostat housing, see the red box in this old photo of my Alfetta. 175-180 is the correct operating temperature, even with AC operating on a hot day, don't drive it above that until you correct the problem. If it climbs above 200 pull over immediately and shut down. I hate to sound gloomy-doomy, but once you've professionally cleaned the radiator, verified the fan is operating as it should, replaced the radiator cap and T-Stat and all soft old hoses (they tend to collapse), if you are still overheating then you are likely looking at a bad head gasket.

**sidewaysalfa** · #21 (**permalink**) 10-09-2009, 09:28 AM

Jim drew a box around the housing. Held on with 2 bolts.
Watch which way the T-stat comes out (otherwise it will be upside down and the car will have permanent air cond ??)
I use orange goop / silicone sealer in place of a gasket (because I usualy forget to order one from IAP/Centeline). Just a little is OK.

An idea on the radiator. Pull it, and blast water thru it. You may loosen enough junk to make it work a little better.
Oh, to bleed the coolant of air when refilling, I first fill the radiator, then squeeze the top radiator hose to burp it while filling some more. Then I run the car and top up the coolant quickly before it gets warm.
Good luck.

superloaf · #22 (**permalink**) 10-09-2009, 08:20 PM

thanks, guys, for all the help--it is much appreciated. new thermostat & radiator cap went in today. running fine at 175. we'll see if that cures it all. radiator feels more evenly hot now too. car runs great except idle is either at 2000 rpm or less than 1000. not sure but think maybe the cold start rich thermo actuator etc. is going on & off randomly. i'll have to check all the spica connections & adjustments and see if i can find what's going on.

but she runs great. new brake lines went in but think i need another bleeding and new pads/rotors as i just can't burn off the rust and glaze from not driving the car for 4 years.

oh, also, my car does not have the coolant bypass restrictor. are these still available anywhere? and i'm surprised mine is missing as this car was previously owned by an alfa mechanic and everything seems well put together. do most people use these or any reasons for getting rid of them?

**La Voce** · #23 (**permalink**) 10-12-2009, 02:57 PM

Bob my Alfetta did not have one and once I cleaned/replaced everything in the cooling system, she runs at proper operating temperature just fine without it.

superloaf · #24 (**permalink**) 10-12-2009, 03:06 PM

ahhhhh, more overheating! ran 30 miles on freeway at cool night and never saw over 175. but then in stop & go traffic, the overheating came back again.

probably the radiator but it's strange how it can cool to 175 with some airflow and then overheat with electric fan running and idling in traffic. other cars i've had either overheat or don't. usually not such a wide range of operating temps with a bad radiator.

damn italians!

**La Voce** · #25 (**permalink**) 10-12-2009, 03:52 PM

Bob,
Here's your checklist. Once completed, you will have a car that cools normally under all circumstances as designed!
-Coolant level topped off
-Cooling fan operates normally
-Radiator cap replaced
-Confirm water pump moving coolant
-Thermostat verified opening at 175 degrees
-Confirm system is bled, not just at the bleed screw, but leave the radiator cap off and idle the engine until the cooling fan cycles twice.
-Replace ALL old hoses, whether they look OK or not
-Professionally clean the radiator ( it cost me $35)
-Replace the head gasket. This what I had to do to get mine cooling properly. If you see any air bubbles in your coolant reservoir upon shut down of a fully warmed up engine, this is the cause.
Hang in There, nothing time and money can't fix

superloaf · #26 (**permalink**) 11-02-2009, 09:53 PM

ok, update here with alfetta's hot head! i removed the radiator and ran some water through it. out came some rusty bits which looked like gravel. not a lot but a few bits. took radiator to LA radiator shop which wanted $75 to clean it out. ok, too rich for my tastes. found another radiator shop who said he would flow test it and then said it was flowing fine.

hmmmm, confused but what could i do but reinstall it and see what happens. and viola, i guess i cleared out some obstruction when i flushed it out and now it's running fine. stays pretty much at 175 until aggressive driving heats it up and then i've seen around 225 when idling in traffic. i'm assuming 225 is within the operating temp of a hot-blooded italian girl so it looks like everything's working well.

well, except for the brakes .... but that's another story.

also, alfetta made her debut at the french & italian car show alongside the likes of jay leno's bugatti on sunday. she's feeling quite proud that she was the only mark I alfetta sedan in the show!

**sfalfa** · #27 (**permalink**) 11-02-2009, 10:11 PM

That's great Bob - though I'm a little concerned with the 225 reading. In all my years with these cars - none of mine have ever run up that hot. I'd keep a close eye and just see how it goes for now - if it creeps up any more, let her rest and cool down. You may be able to keep it going for a while longer before you need to reinvestigate the cooling.
Glad to hear you were able to 'represent' at the show - get used to being the only mk 1 at any event!

superloaf · #28 (**permalink**) 11-02-2009, 10:17 PM

Quote:

Originally Posted by sfalfa

That's great Bob - though I'm a little concerned with the 225 reading. In all my years with these cars - none of mine have ever run up that hot. I'd keep a close eye and just see how it goes for now - if it creeps up any more, let her rest and cool down. You may be able to keep it going for a while longer before you need to reinvestigate the cooling.
Glad to hear you were able to 'represent' at the show - get used to being the only mk 1 at any event!

Alfaguy35 · #29 (**permalink**) 11-02-2009, 10:19 PM

Bob,

225 is too hot, that is on the edge of headgasket blowing territory. My Alfetta runs at 175 all the time. Are you sure that the fans are cycling on and off? How old is the waterpump and did the car have coolant or water in it when it sat? If the pump impeller is corroded or the housing is worn that would make the pump not work well at low rpms.

superloaf · #30 (**permalink**) 11-02-2009, 10:34 PM

fans working fine but i did notice that the radiator at times is pretty cool at the top while hot at the bottom. the radiator guy who knew about alfas said that the radiator is divided into 2 separate sections and that this was normal. however, the weird thing is that the fan is skewed towards the top so when it runs, the air coming out the back is cool since most of the air is being pulled through the cooler section of the radiator. i took off the fan and rotated it 180 degrees so it pull more from the bottom and it appears to be beneficial except that it now has almost no clearance to the metal cooling hose at the front of the engine.

and i hope 225 is ok as i've seen 250 before flushing the radiator. isn't 175 pretty damn cool for any car? what do normal cars run at? maybe i'm thinking oil temps but i thought right around 212 was where it should be.