Alfetta Cooling Problem

superloaf · #1 (**permalink**) 10-02-2009, 09:12 PM

so i finally got alfetta up & running after about 3 years and although she's running great, i'm having an issue with the cooling system. the water temp rises to close to 250 degrees while in traffic. when on the highway with air flowing through the radiator, the temp goes down to 175 and stays there. the cooling fan comes on as it should and the overflow container is full and actually boils over slightly when temp is near 250. however, while letting the fan run to cool the radiator i noticed that the radiator was actually cool to the touch on the aluminum while the ends where the hoses connect and thermo switch resides are super hot. also, the hoses are all very hot.

so what's going on? do i have air trapped in the radiator? is something clogged? any ideas?

thanks

alfalfa339 · #2 (**permalink**) 10-02-2009, 10:38 PM

Check your thermostat to see if it is opening?

superloaf · #3 (**permalink**) 10-02-2009, 11:14 PM

Quote:

Originally Posted by alfalfa339

Check your thermostat to see if it is opening?

**bayalfagtv6** · #4 (**permalink**) 10-02-2009, 11:32 PM

Radiator could need rodding. Had my 83 GTV6 which always overheated in traffic, had the radiator rodded and that solved the problem. Runs right around 175 or so.

superloaf · #5 (**permalink**) 10-03-2009, 01:19 AM

also, it was fine before parking a few years ago.

superloaf · #6 (**permalink**) 10-03-2009, 02:36 AM

what's rodding?

**bayalfagtv6** · #7 (**permalink**) 10-03-2009, 04:07 AM

I think that's what they call it. radiator shop removes 1 end of the radiator and run rods thru the cooling passages to remove scales and deposits which have built up. If the radiator is cool in the middle (passgeways) you may not be getting coolant thru the passageways, which could cause the overheating. Sort of like recoring the radiator without actually replacing the core.

lewong · #8 (**permalink**) 10-03-2009, 12:29 PM

I sort of had this problem. Check the thermostat, air in the cooling system, blockage in the radiator. I use Redline Water Wetter.

Does the overheat light come on? Does your Alfetta have AC? I found that having the AC condensor in front of the radiator doesn't help with cooling.

The thermostat is in the cast housing at the other end of the top radiator hose.

Air in the cooling system can reduce cooling. There is a bleed screw on top of the water pump and at the thermostat housing.

I don't know if this applies in your case but there is also a coolant bypass restrictor in one of the hoses. The correct thermostat open and closes the supply to this hose. Google alfetta bypass restrictor

Rich Hirsch mentioned the bypass restrictor in a 1996 Alfa Digest post:

"Here's what Fred Di Matteo said about it in
an article in Velocissima from ca. '91:"

"The little known restrictor in the bypass hose has a spring loaded valve
which allows more water to flow through the engine block and cylinder head
when the thermostat is fully closed in all weather and when the water temp
is below the operating range."

"The thermostat is shut tight until the water temperature increases to a
point to begin letting the coolant flow through the radiator. As that
happens. the back pressure on the bypass restrictor closes to allow more
flow through the radiator. The function of the thermostat is to control
the rate of coolant flow through the radiator so it doesn't flow so fast
it can't be cooled enough in the radiator. People who mistakenly remove
the thermostat succeed in making matters worse, not better."

"Another function of the restrictor is not only to circulate water within
the engine for quicker temperature rise, but it also gets hot water through
the heater in the car on those cold. cold mornings. The restrictor must be
installed in the bypass hose so the valve opens in the direction of flow.
The small opening is not sufficiently large to pass all the water necessary
when the engine is cold and the thermostat is closed."

"To clarify the restrictor's installation, it goes in the bypass hose spring
side down, so the moveable disc faces the thermostat housing"

superloaf · #9 (**permalink**) 10-03-2009, 01:35 PM

lewong, thanks for that info. i didn't know anything about that.

did you solve your problem? it sounds like exactly what mine is doing although i think mine gets a little hotter into actual overheating.

mine has AC but not operational. car used to run fine with no cooling issues but haven't driven it in quite a while. i'll check for air trapped in radiator and then i'll assume thermostat which is probably the problem. also, i'll check that special restrictor.

thanks

superloaf · #10 (**permalink**) 10-04-2009, 04:04 AM

apparently, alfetta has decided to fix herself yet again! italian tune up at work i guess but the temp today was right at 175 and all i did was open radiator cap to check level which was full. oh, well, not complaining but the car is running great. now if only the brakes would unglaze themselves and start working right, everything would be great!

alfalfa339 · #11 (**permalink**) 10-04-2009, 07:35 AM

Quote:

Originally Posted by superloaf

apparently, alfetta has decided to fix herself yet again! italian tune up at work i guess but the temp today was right at 175 and all i did was open radiator cap to check level which was full. oh, well, not complaining but the car is running great. now if only the brakes would unglaze themselves and start working right, everything would be great!

**sidewaysalfa** · #12 (**permalink**) 10-04-2009, 12:33 PM

Bob,
Not to bum you out, but remember the temperature here in LA dropped on Saturday from last week.
You may have a marginal / clogged radiator. Your said that some places on the radiator did not feel hot may be a clue.
Recently I had mine done because it was displaying some of your symptons on cool days. Now my Alfetta only overheats on hot (+95deg) days in stop and go / city traffic with the A/C on. A day like Friday and yesterday (80ish) no problems. With the cool weather upon us I should not have to worry about it till next summer.
Cost was less than $50. The radiator is one of the easiest things to replace on our cars.
obtw - I see you are in LA area. So what are you doing the first of Nov???
check out the site: franceanditaly.com

superloaf · #13 (**permalink**) 10-05-2009, 09:27 AM

Quote:

Originally Posted by sidewaysalfa

Bob,
Not to bum you out, but remember the temperature here in LA dropped on Saturday from last week.
You may have a marginal / clogged radiator. Your said that some places on the radiator did not feel hot may be a clue.
Recently I had mine done because it was displaying some of your symptons on cool days. Now my Alfetta only overheats on hot (+95deg) days in stop and go / city traffic with the A/C on. A day like Friday and yesterday (80ish) no problems. With the cool weather upon us I should not have to worry about it till next summer.
Cost was less than $50. The radiator is one of the easiest things to replace on our cars.
obtw - I see you are in LA area. So what are you doing the first of Nov???
check out the site: franceanditaly.com

**sidewaysalfa** · #14 (**permalink**) 10-05-2009, 11:56 AM

"but this car is strange in that the harder i drive it, the more it tends to fix itself"
Not strange at all. Others on the bb have documented this fact.
Another radiator note: After I had mine cleaned out (they said it had 20% blockage) it still overheated about the same. I removed it (again) and noticed the shop had painted it with something like roofing tar. SO I completely stripped that gunk off and lightly sprayed it with black hi temp BBQ paint. Now the car only has overheating on a HOT day and the A/C running. Turn off the A/C and the car cools down in about 1 mile of slow city driving.
A quick way to test the gauge is to unplug the cooling fan and watch the temp gauge and idiot light. That works on my cars when I forget to plug it back in after some repair.

France and Italy
Get to the park by about 8 - 8:30am. They have somebody selling coffee.
For more discussion, look here:
http://www.alfabb.com/bb/forums/car-...-1-2009-a.html

**sfalfa** · #15 (**permalink**) 10-05-2009, 12:51 PM

Quote:

Originally Posted by superloaf

...running not much higher than 175 although that temp does seem awfully low. are those gauges way off or do they run that cool?