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OMG ! I've never seen such "shrouds" ! Maybe they are a cold climate thing. Get rid of them. When I lived in the UK and had an old SAAB 96 it was useful to block the radiator to get the car to warm up in much the same way. My utterly, painfully original GTV6 has no such shrouds. They are the problem, right there.
 

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Yup. Bad design in my book. The actual blade shrouds/cowls should be held in place by just several simple struts, thus allowing full flow through the radiator while still enhancing the efficiency of the blades themselves.
 

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Del, later cars do have complete shrouds but these sit well away from the radiator and smoothly direct airflow through large fan apertures. These latter cars also have aerodynamically designed air intakes on the front of the car that catch, compress and direct huge amounts of air through the radiators. The air flow through the front of the 116 GTV is (IMHO) pretty terrible. Alfa recognised this when it redesigned the front for the GTV6. This redesign ruined the lines of the front of the car but facilitated a larger radiator aperture.
This is why I added an oil cooler behind the radiator of my 79 2 litre. Where else can it go? The other dumb thing is that the air con condenser is added in front of the radiator. This severely reduces air flow at low speeds. given how poor the air con is in my '79 I removed it. It was, quite literally, dead weight.
The oil cooler option not onely keeps the engine temp down, it keeps the oil temp down which means the coolant acts directly on the components inside the engine. This is far more thermodynamically efficient. Alfa recognised this which is why they have finned sumps and large oil capacity.
Finally, the GTV6 bumper bar is a direct impediment to air flow and the air dam is far from optimised for cooling. Again IMHO...

On another note. By the 80's it is pretty clear that Alfa was struggling. They never fixed the gear change or synchro weaknesses and the 116 platform was milked until they cold get no more from it. The 116 was the last true "Alfa" platform. The 1980 redesign is a compromise. They kept the brilliant motor for decades but in a way that was all they could salvage.
 

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This is why I added an oil cooler behind the radiator of my 79 2 litre. Where else can it go? The other dumb thing is that the air con condenser is added in front of the radiator. This severely reduces air flow at low speeds. given how poor the air con is in my '79 I removed it. It was, quite literally, dead weight.
The oil cooler option not onely keeps the engine temp down, it keeps the oil temp down which means the coolant acts directly on the components inside the engine. This is far more thermodynamically efficient. Alfa recognised this which is why they have finned sumps and large oil capacity.
Finally, the GTV6 bumper bar is a direct impediment to air flow and the air dam is far from optimised for cooling. Again IMHO...
I agree with most of your points except the one about the A/C condenser in front of the radiator. While not the absolute best layout from a thermodynamic standpoint, this configuration is used by 99% of cars on the road today, and it is necessary from a packaging standpoint. The key factor is that the engineers need to design the extra capacity in the engine cooling and fan system to absorb the heat shedded by the condenser while the A/C is running.

Alfa Romeo in the 1970s and 1980s was probably not as diligent about this as most would have been. It must be said that in my '81 GTV6, I have not bothered to remove the non-functional A/C condenser from its location in front of the radiator, and the engine runs at the rated temp of the thermostat in any condition, but it would probably struggle at low speeds with hot air from the condenser adding to the load!
 

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Uh... you can search but I don't think you'll find an automotive air conditioning condenser that's mounted anywhere BUT in front of the radiator.

And Millsy, in criticizing the 116 series, aren't you forgetting the Zagato RZ and SZ spinoffs of the excellent 116 chassis? Go back and read the road test reports on that car, and you will find it would run away and hide from many contemporary sports cars on the track.

ok... back to Gepetto's topic. Sorry...
 

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Discussion Starter #86
Continuing the off topic, I confess the 116 chassis (at least the GTV6) is superb, but the cooling system isn't really adequate for slow moving (with or without air conditioning). I had a Milano 3.0 that was more or less the same story, though it too never overheated on me. And @cda951 is right - by the 80's Alfa was in trouble. I wish they had the resources to improve the transmission and gearshift (oh, maybe a 6th gear, better feeling shift action).

Then again, these cars weren't really designed to just crawl around town anyway...for that you buy something else.
 

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I had my stock radiator rodded out and flushed. They discovered some small cracks and took care of them. Car runs just north of the 175* mark, in 100* plus weather. I do not have the AC condenser mounted, so maybe that has something to do with the better-than-reported-here performance.

Interesting issues with the shroud. That flap design is quite common in newer vehicles, and should have alleviated the airflow problem at high speed. I had planned to go to something like that when I reinstalled the AC. A rethink is in order.

Thanks for sticking with the analysis. Sometimes this gets pretty tedious.
 

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Discussion Starter #88
I want to be scientific about this, so multiple tests under the same conditions - but with one new thing added/taken away - are in order. Once I take out the bottom rubber flaps and open up more of the shroud, let's see what happens. This weekend should be about the same temperature in NYC last last, so it lends it self to science!
 

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Science! I love Science. Nothing better than the never ending search for knowledge, lol.

Well, a very cold beer on a very hot day is pretty darn nice...

Or, a great drive in any Alfa on a perfect winding road.

Keep us posted.
 

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Discussion Starter #90 (Edited)
Update - No dice!

Earlier today I was able to get the car up on the lift and pull out the bottom portion of the shroud (rubber flaps shown in previous pictures). Driving, it seemed to help at first, but there was too much traffic to really tell. Then, on the highway, the temp seemed normal but then I realized the fans were on. When I heard the fuse click for them to go off, the temp started rising again.

Determined to get a good highway run in for the sake of science, I took the car all the way from Queens to the Sagtikos Pkwy when there was no traffic. The temperature kept rising almost to the point to where the fans would turn on (see picture). I turned the heat full blast and the temp decreased a little, but never to 180 (even while doing 75mph!). The only way to get the temperature down was to coast in gear. When I pushed the car, the needled rose toward, but never quite reached, 100C/212F line on the gauge. While on the highway with the heat on, I was successful in keeping the fans off - which means water temp less than about 193.

Discouraged, I stopped at the Glen Cove Rd. Dunkin Donuts for an iced coffee (the heat in the car took it's toll on me). When I set off again, I decided to take empty Northern Blvd back as it was bumper to bumper on the highway heading back to NYC - and this turned out to be a lucky decision. While sitting at the light waiting to turn west onto Northern Blvd, the car sputtered and almost died. I gave it some throttle and it came back to life, but now the air conditioning had stopped working. The temperature kept rising and not really decreasing at stop lights with the fans on, so I popped the hood open while driving. As long as I was moving more than about 25mph, this actually lowered the temperature to 180. The faster I drove, the quicker the temperature decreased. The physics of this makes sense to me - the engine heat had somewhere to escape from.

When I got home, I opened to hood to find that the driver's side fan was kaput. As it's on the same fuse as the electromagnetic clutch for the A/C (#3), I suspect this fuse has blown. (I didn't check as I was too tired from driving 80 miles with the heat blasting for at least 50 miles). Earlier in afternoon the A/C worked well and was practically freezing me out of the car, so I'm not sure why the circuit would have blown the fuse.

At this point, it seems that taking parts of the shroud has had a positive, albeit small, effect. Now, at least turning on the heat in the car will actually cool down the water temp a little, so it seems that improved airflow is helping and I can proceed cutting some more holes in the shroud. But my sense is that something else, possibly more serious, is wrong. I reckon the next step is to 1) replace fuse #3, 2) check ignition timing. If igniting timing is correct and/or does nothing when adjusted, then 3) change thermostat with new one. Then work my way to changing hoses and perhaps another radiator is in order if it comes to that. (Speaking of which, does anyone know if the OEM ones from Alfissimo.com are actual, exact OEM radiators, and not aftermarket?).

As always, I appreciate all your feedback. You guys truly are the best!
 

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I know that this is treating the symptoms rather than the cause but Serpent Autosport sell a louvered tea tray that helps ventilate the engine compartment and IMO looks pretty good.
 

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Do you still have the Milano fan or the original twins to substitute for the Spal setup, the twins would be better because they allow the system to work as designed one fan for the air-con when used and two fans for the thermal dynamics of the cooling system.
If you remove the thermostat your self to test it, this would be a good time to check flow through the radiator and engine block simply putting a garden hose into the radiator hose and watch how it flows out through the thermostat housing. (if you live in an apartment block this might not be ideal)
 

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Discussion Starter #93
@sportiva I do have the original twins to substitute. I wonder if I can take the Spal fans out of the current shroud entirely and put them into the frame of the originals. The Spal fans move much more air (shroud or no shroud) than the originals. For checking flow, you mean literally sticking a garden hose to one of the hoses that hooks up to the thermostat?
@alfaparticle I've thought of that. What happens when it rains, though? Water must get through into the engine bay...
 

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The louver openings face backwards so if you are in motion not much rain will get in there. I once drove my GTV6 in the rain and I had no problems.
 

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Pull the thermostat housing top off remove it from the radiator hose then insert the garden hose into rad hose use a rag to stop any backflow then watch for rust or debris as it comes through the thermostat lower housing when the water runs clear you can reverse the flow or backflush the system. This is a flow test to check for a major blockage as even with some of the tubes blocked water will still flow around the blocked tubes then on through the system and it is not as good a professional backflush. If the radiator was re-cored only a few years ago the system should be relatively clean with no chunks of rust or calcification flowing through as you flush it.
 

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Discussion Starter #96
Update - almost there!

A quick update on the heat situation with my engine. After checking the ignition timing, it turned out to be way too advanced (13 degrees!). How it got there, I have no idea. After reducing it to 6, and then 4 degrees, it ran quite a bit better and smoother. The temperature also seemed to be better kept nearish 180, though still a little warmer than normal at speed. I'll need to do another open road highway test (which is not easy in the NYC area). Under the limited testing I could do today, the engine temp does not shoot up as rapidly under acceleration. Win!

I can also confirm that coolant flow is adequate and no chunks of rust or debris were circulating in the system.

It seems the Ansa headers and downpipes are radiating an awful lot of heat. Again, while more testing is required, it seems that that's also something that needs to be addressed. I'm thinking of sending them off to Jet-Hot for a ceramic coating. Apparently, they reduce radiated heat by 50%...that can't hurt!

We're almost there guys! Thanks for all your feedback.
 

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A quick update on the heat situation with my engine. After checking the ignition timing, it turned out to be way too advanced (13 degrees!). How it got there, I have no idea. After reducing it to 6, and then 4 degrees, it ran quite a bit better and smoother. The temperature also seemed to be better kept nearish 180, though still a little warmer than normal at speed. I'll need to do another open road highway test (which is not easy in the NYC area). Under the limited testing I could do today, the engine temp does not shoot up as rapidly under acceleration. Win!

I can also confirm that coolant flow is adequate and no chunks of rust or debris were circulating in the system.

It seems the Ansa headers and downpipes are radiating an awful lot of heat. Again, while more testing is required, it seems that that's also something that needs to be addressed. I'm thinking of sending them off to Jet-Hot for a ceramic coating. Apparently, they reduce radiated heat by 50%...that can't hurt!

We're almost there guys! Thanks for all your feedback.
Hmmm, in general it is overly retarded ignition timing that causes hotter engine temps, but if your engine runs better then that is good. I'd be curious to know the before and after total ignition timing advance, but that's OK.

While it might be the case that the factory cast-iron exhaust manifolds retain more of the exhaust heat, I seriously doubt that whatever additional heat radiated by the aftermarket headers would cause the engine coolant temperature to be warmer at speed. Think about it. There is airflow underneath the car while driving at speed that is flowing along the exhaust system and moving in the opposite direction of the radiator. Any such heat from the headers would be more of an issue at idle/low speed, during which you say the temps are OK.

I would ditch those shrouds completely and report back.
 

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Discussion Starter #98 (Edited)
I'd be curious to know the before and after total ignition timing advance, but that's OK.
If I understand you correctly, we were at 13 degrees before TDC, now I'm at 4 degrees. (I did not record advance at higher RPM, just idle... but it didn't look like anything unusual).

If further testing doesn't change anything, then I may just put the old shroud-less twin fans in for a test.
 

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Gepetto, I'm wondering... what was the air temperature on this day? Also, the thermostat is probably set to open at 83c So, unless I've missed something, your car should run at that temperature as a minimum. Here in Oz (South Australia) we worry when the temp of the car approaches 100c. For those of us old enough to have run cars with water in the radiator boiling point was an issue! However, modern coolants are totally fine up to about 120c. On a hot day (43c Low humidity) I have run my GTV4 at 105-110c with no problems. Though you do need to keep moving. As a cyclist I can assure you that the temperature of the road surface in these conditions is around 60-70c. However, turning on the aircon will add heat: lots of it.
The shrouds are definitely a problem. As would be a failed fan. The air con condenser was installed at an angle in my GTV4. It was a very effectively air blocker.
Have you checked: timing? mixture (a little bit lean will really push up temperature). With regard the GTV6 there are lots of places that air can get in after the MAF and before the chambers as there are lots of rubber parts that routinely perish. This was my first challenge. I have replaced virtually every hose and rubber seal. I'm in the process now of doing all the rubber and gaskets on the inlet tubes. Do you have one of those infra red heat sensor guns? They're like a laser pointer but they measure temperature. I was recently (and still am) dealing with blockages in the idle jets of my GTV4 and i can tell which cylinder is lean or rich simply by the exhaust manifold temp. At 280c it is lean (ie the car is running rough because the jet is blocked again). At 100c it is rich. Check this. Lean = Hot.
A list of leak sites from the MAF to the cyclinder:
The Snorkel can have fine cracks in the bellows or around the junctions with other pipes.
The other pipes can have hidden cracks or just be perished.
The clamps can be loose.
Check every joint, connector or seal on the plenum (there is at least 7 places for air to get in)
Under the Plenum the rubber connectors to the intake runners perish.
The clamps need to be tight.
The intake runners have seals that might be leaking. In my car the nuts on these were not tight. They were done up but way too easy to undo.
The injectors have rubber seals.

You get the picture. I'm an amateur but i'm fairly sure that you can have an OK mixture at idle but when running at speed go lean due to an air leak that opens when the intake pressure is low (ie sucking lots of air).

One final comment. You guys in America make lots of comments about it being really hot and humid. Humid helps heat transfer but not evaporation. Hot humid days conduct more heat away than hot dry days. Cars don't have evaporative cooling like us humans... just saying... ;)
 

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Discussion Starter #100
Hey @Millsy thanks for your thoughts! The ambient temperature on the test runs ranged from 70F (21C) to 100F (38C). Truth be told, this issue has been going on for a while, even with temperatures around 50F (10C). Once the temperature drops below freezing, I have not noticed this issue.

A/F mixture was tested both at idle and under load (from light maintenance throttle all the way to WOT) and it is not lean and hovers at 14.7 under most conditions, and 12ish at WOT. Though I do need to get a heat gun - I don't have one of those...
 
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