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Discussion Starter #1
my 92 L does just exactly what alot of yours do. overheats after a bit of driving.

heres what i do know:
1. the fan DOES NOT work. i have it wired to 'low' speed and doesnt really do the trick. how can i rig it to work on 'high'?

2. it has an old water pump
3. the radiator COULD BE clogged
4. the coolant reservoir has a crack a leaky crack (new part is on its way to my front door)
5. it didnt get hot near as bad untill i blocked off the heater core

so i have a few questions.
the first one is, is there a high flow radiator that is fairly easily swapped in? is there a post on that?

2. can someone point to the direction of the post on temp switch and wiring and fan issues?
thanks :eek:
 

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How old is the thermostat? These can fail stuck closed, open or partially open, giving different symptoms. Overheating can easily result from a partially stuck thermostat.

Sounds like the radiator is not functioning properly. Later 164 had single row radiators (which would be faster flow) which neatly update the double row radiator originally installed. The cooling system works much better with the later single row radiator. Alfa made the change so the single row is an approved factory part.
 

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I remember my original Alfa Giulia Sprint GT, which came with a soldered together thermostat, cleverly designed to fail closed when the soldering eventually failed. I may still have the pieces of that crap around as a classic example of really poor design work.
 

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my 92 L does just exactly what alot of yours do. overheats after a bit of driving.

heres what i do know:
1. the fan DOES NOT work. i have it wired to 'low' speed and doesnt really do the trick. how can i rig it to work on 'high'?

2. it has an old water pump
3. the radiator COULD BE clogged
4. the coolant reservoir has a crack a leaky crack (new part is on its way to my front door)
5. it didnt get hot near as bad untill i blocked off the heater core

so i have a few questions.
the first one is, is there a high flow radiator that is fairly easily swapped in? is there a post on that?

2. can someone point to the direction of the post on temp switch and wiring and fan issues?
thanks :eek:
Hi Ssteak, see my post earlier today. Before I came across the latest fix, I replaced the plastic fluid expansion tank last year as it had small cracks in it and would not hold the pressure needed. I had to replace the radiator about 2 years ago as the old one had a cracked seam and again, would not hold the pressure. Also, my mechanic replaced the 40 amp relay on the firewall behind the fluid overflow tank. That relay was working intermittingly. He also cleaned the contacts on the radiator temperature relay as they would get dirty and not conduct well. He also did something to the relays so that I have only a high speed fan, no low speed.

Lastly, when the temp would continue to heat up to 200 or 205 degrees, the radiator fan would come on and reduce the temp to about 190 degrees and then cut off. The car would heat up agiain to 200+ degrees, and the fluid would eventually start to exit via the pressure relief cap.

Seeing this pattern and after testing all other items (i.e. pressure testing the system to see if it could hold the pressure needed), my mechanic suggested an adjustable aftermarket radiator fan thermostat switch. He also replaced the water thermostat at the same time as we had no record if it being replaced. Center Line Afla sells this adjustable part and here is a link to their website.

Centerline Products: FT636 Adjustable Radiator Fan Thermoswitch

My part looks exactly like theirs. If your radiator fan is working but just cutting off too soon, I suggest this modification. Also, regarding the water pump, my mechanic says they either work or they do not work. There is no period where their pumping abilities start to deminish. So, if yours is not leaking or making noises, it is probably ok. My car has 78K miles and the pump is still original.

I hope this helps!

Jeff
Dallas, Texas
 

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I don't know specifically about the newer water pumps used in Alfas, but the water pumps in older Alfas would be less effective as they aged because coolant cavitation seemed to cause erosion of the impeller blades, and because of the impeller blades being eaten away by corrosion due to acids buildup in the old style coolants, thus reducing pumping efficiency.

I remember seeing water pumps with severely eaten away blades.
 

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I don't know specifically about the newer water pumps used in Alfas, but the water pumps in older Alfas would be less effective as they aged because coolant cavitation seemed to cause erosion of the impeller blades, and because of the impeller blades being eaten away by corrosion due to acids buildup in the old style coolants, thus reducing pumping efficiency.

I remember seeing water pumps with severely eaten away blades.
Not a problem in any 12v or 24v V6 engines I have ever seen. Most cars nowadays actually use coolant made for them and with proper maintenance schedule impeller erosion has never been an issue in the Alfa V6.

I use distlilled water with coolant, not to really protect the cast iron impeller but to protect the aluminum engine block and heads.
 

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my 92 L does just exactly what alot of yours do. overheats after a bit of driving.

heres what i do know:
1. the fan DOES NOT work. i have it wired to 'low' speed and doesnt really do the trick. how can i rig it to work on 'high'?

2. it has an old water pump
3. the radiator COULD BE clogged
4. the coolant reservoir has a crack a leaky crack (new part is on its way to my front door)
5. it didnt get hot near as bad untill i blocked off the heater core

so i have a few questions.
the first one is, is there a high flow radiator that is fairly easily swapped in? is there a post on that?

2. can someone point to the direction of the post on temp switch and wiring and fan issues?
thanks :eek:
1. the fan DOES NOT work. i have it wired to 'low' speed and doesnt really do the trick. how can i rig it to work on 'high'? What did you rewire/modify?

2. it has an old water pump. Who cares if it is not leaking?
3. the radiator COULD BE clogged Yes or bottom fins could be dust from corrosion.
4. the coolant reservoir has a crack a leaky crack (new part is on its way to my front door) That will help and be sure cap is good, too.
5. it didnt get hot near as bad untill i blocked off the heater core So where did you put valve in hose coming off rear of front head on 12v V6 engine? Also are small coolant hoses into and out of throttle body from tee fitting out of rear head connected and open to bleed air into coolant tank?

Did you bleed thermostat by opening 14mm hex head bleeder screw on top of thermostat?
 

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Discussion Starter #8
1. the fan DOES NOT work. i have it wired to 'low' speed and doesnt really do the trick. how can i rig it to work on 'high'? What did you rewire/modify? i just ran a wire crossing the white and black wire near the temp switch (driver side of radiator)

2. it has an old water pump. Who cares if it is not leaking? touche
3. the radiator COULD BE clogged Yes or bottom fins could be dust from corrosion. wouldnt surprise me. car has sat for a few years
4. the coolant reservoir has a crack a leaky crack (new part is on its way to my front door) That will help and be sure cap is good, too. ok, cap is good. i noticed that the previous owner bypassed the coolant level sensor wires. im guessing it was throwing a light for no reason. it holds good level
5. it didnt get hot near as bad untill i blocked off the heater core So where did you put valve in hose coming off rear of front head on 12v V6 engine? Also are small coolant hoses into and out of throttle body from tee fitting out of rear head connected and open to bleed air into coolant tank? i believe the hoses are open. should i pull the hoses and check for blockage while im replacing the radiator? i put the heater core shut off valve in the middle of the hose that comes out of the back of the front head like you say.

Did you bleed thermostat by opening 14mm hex head bleeder screw on top of thermostat? yes. it doesnt really bleed. it just pours out coolant... (which i thought to be odd) is that normal?
 

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Discussion Starter #9
does the newer style radiator bolt up in the older models??? im sure i can do some hose modifications if necessary
 

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1. the fan DOES NOT work. i have it wired to 'low' speed and doesnt really do the trick. how can i rig it to work on 'high'? What did you rewire/modify? i just ran a wire crossing the white and black wire near the temp switch (driver side of radiator)

2. it has an old water pump. Who cares if it is not leaking? touche
3. the radiator COULD BE clogged Yes or bottom fins could be dust from corrosion. wouldnt surprise me. car has sat for a few years
4. the coolant reservoir has a crack a leaky crack (new part is on its way to my front door) That will help and be sure cap is good, too. ok, cap is good. i noticed that the previous owner bypassed the coolant level sensor wires. im guessing it was throwing a light for no reason. it holds good level
5. it didnt get hot near as bad untill i blocked off the heater core So where did you put valve in hose coming off rear of front head on 12v V6 engine? Also are small coolant hoses into and out of throttle body from tee fitting out of rear head connected and open to bleed air into coolant tank? i believe the hoses are open. should i pull the hoses and check for blockage while im replacing the radiator? i put the heater core shut off valve in the middle of the hose that comes out of the back of the front head like you say.

Did you bleed thermostat by opening 14mm hex head bleeder screw on top of thermostat? yes. it doesnt really bleed. it just pours out coolant... (which i thought to be odd) is that normal?
1. If you cross (jump) red wire to black wire instead of white wire at thermal switch fan should run all the time on high with key on. Not the ideal way but OK for testing fan speed. You need to verify thermal switch low and high temp switches work and use it for automatic operation.

5. It is best to be sure those two small hoses one from tee to throttle body and other from throttle body to coolant tank are open to flow to tank.

If bleed plug on thermostat runs solid coolant that is normal when all air out of system.
 

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while that rad. is out...

I recently replaced my rad. - it was the orig. from '93, with about 80K miles - it finally started leaking past the plastic side-header tank seals. Anyway..

As I was about to place the new one in, I thought I'd see if any debris was in the A/C condenser imm. in front of the rad. When I held a drop light behind the condenser fins and looked through, it seemed pretty clean - HAH!

I used a garden hose to shoot a stream of water through it, and mud came out. The amount of dirt caught in there was truly impressive. I sprayed on Simple-Green, let it soak for a minute, and flushed it with the hose, repeating - front-to-back, back-to-front - until the runoff was finally completely clear. Now the drop light test made the condenser fins gleam.

Just thought I'd pass along that little tidbit.

Good luck with the coolant system reconditioning.
 

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Discussion Starter #12
has anyone measured the actual block temperature?? everything checks out and its still able to get to 220 + if i let it. (thats driving at 65 mph) im suspecting a temp switch failure, or failure to send the right temp to the gauge.

what is the block temp at 190 - 195 degrees?
 

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Discussion Starter #13
I recently replaced my rad. - it was the orig. from '93, with about 80K miles - it finally started leaking past the plastic side-header tank seals. Anyway..

As I was about to place the new one in, I thought I'd see if any debris was in the A/C condenser imm. in front of the rad. When I held a drop light behind the condenser fins and looked through, it seemed pretty clean - HAH!

I used a garden hose to shoot a stream of water through it, and mud came out. The amount of dirt caught in there was truly impressive. I sprayed on Simple-Green, let it soak for a minute, and flushed it with the hose, repeating - front-to-back, back-to-front - until the runoff was finally completely clear. Now the drop light test made the condenser fins gleam.

Just thought I'd pass along that little tidbit.

Good luck with the coolant system reconditioning.
did cleaning the condenser help? are you seeing lower temps??? the fins on my condenser at the bottom (in the bumper grille) are FU*KED up like mad.
 

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did cleaning the condenser help? are you seeing lower temps??? the fins on my condenser at the bottom (in the bumper grille) are FU*KED up like mad.
I can't swear to it, but the temp. regulation range seems to be very consistent and never high, now, even in hot weather or stuck traffic, w/ or w/o the AC running. But, of course, a new rad. was fitted at the time I cleaned up the condenser.

I've been told by more than one old-school mechanic over the years that making the effort to carefully straighten out (or flush debris from) condenser/radiator fins is never a waste of time.

If your lower section fins are bent 90 degs., they're blocking air instead of radiating heat into a passing air stream, so I'd take a machinists pick and bend those babies back into the air flow again. It can't hurt - as long as you don't pierce the refrigerant/coolant pipes, of course(!).
 
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