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Discussion Starter #1
I'll admit right off the bat, that what I don't know about cars could fill the Grand Canyon, however I am very curious ( or as some say nosy) and want to learn. My current issue is this. My '79 Spider Veloce is pretty much my everyday driver. I drive it into Manhattan ( I work off hours) which is about 18 miles each way. Often I get stuck in traffic such as last night when I had the joy of moving two miles in 45 minutes and at one point just sitting at a dead standstill for 10 minutes on the FDR while people passed us walking along the East River. Now the car often runs a little hot which doesn't affect it as long as I'm move along at a decent clip {No really officer the faster I drive the cooler the engine stays} but in stop and go traffic it hits the 220 mark and starts idling rough and acting like it's not getting enough gas in which case it'll start to stall. When traffic starts moving again it still acts like it's still not getting enough gas but as I move faster this stops in about a minute of less, the air from moving over 30 mph cools the engine back down to reasonable parameters and it runs fine as if it was all in my imagination. Now I have had both the tank cleaned so it's not stuff in the gas or gas tank and there is an electric fan that runs to cool off the radiator which had been sent out to be recoiled (correct term??) so everything SHOULD be in effective running order. How do I avoid this over heating and why does it seem to affect gas flow? Possible solutions? ideas? And no saying stay off the FDR. ;) Oh, and I also know to run the heater to try and cool the car down, but this doesn't seem to be very effective.
The mechanic and I seem to be slightly baffled about the its running a little hot and of course it doesn't peg 220 when he's around. Anyone else having/had this experience?
 

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As far as the overheating goes I would have the radiator serviced out by a radiator shop. If you reach thru the grill opening with the car running and hot you will most likely find some cold spots, this is caused by restrictions in the radiator usually found on the outside along the edges. The radiator should be nearly the same temp everywhere on the core. The poor running is most likely caused by the thermostatic actuator over extending when it gets hot, this will cause the injection pump to start binding up and once the car cools down a little the actuator retracts and all is fine. I have seen linkage inside the pump broken from this. The binding can occur with as little as 32mm to 33mm extension as 31mm should be the maximum.
 

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If you had your radiator serviced recently and its known good, and you have an electric radiator fan, here are some suggestions. First, when the radiator was serviced, did your mechanic bleed the air out of the system? Perhaps you have air trapped within the block or intake manifold that is impeeding full flow. On your electric fan, do you have a relay on/off w/ thermostat? Do you here it on when sitting still? Next, how long has it been since you changed the thermostat? Perhaps its not completely opening up and not letting enough H2O through at idle. Finally, is the water pump known good? Maybe its not pumping enough at idle.

Just a few things to think about and inspect. You will not overheat at 220 if you have a 50/50 mix of antifreeze and distilled water.

Best of Luck,
John M
 

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Discussion Starter #4
I put a 160 degree theromstat in there and it seems to be running cooler - a little, but the guage is still reading the same. However the car does seem to be running a little cooler when not stuck over an hour in stop and go traffic.

Rad. has been recored and fan is blowing proper direction. I'm considering a larger fan, but going to wait a few more days and see if the thermostat is helping.

Thanks for advice help and suggestions. They are VERY appreciated!

Sarah.
 

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Another thing to check is the restrictor in the bypass hose (if '79s have 'em). If it's missing, and when the stat opens, a fair portion of the coolant will go from the intake manifold right back to the water pump bypassing the radiator. Did either stat have a small disc, about 30mm in diameter, attached to the bottom?
 

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Sarah,

There are a couple things that nobody else has discussed yet. It has to do with cooling and coolant flow. First of all, you need to make sure that you are using good coolant. I assume that your coolant was recently replaced when you had the radiator re-cored. If so, and your thermostat and radiator are both good, and your fan is working, and it's blowing in the right direction, then there are three other possibilities:

1. Replace your radiator cap. A very small item (and cheap too!), but a bad cap can let air into the system and makes the 'flow' reduced as a result.

2. Do you have 'headers'? If so, the extra underhood heat may be causing your overheating. If that's the case, you need to either wrap your non-stock headers in 'header-wrap' (available from www.pegasusracing.com), or have your headers ceramic coated (by some place like 'jet-hot').

3. Is your engine running a higher than stock compression ratio? In other words, has someone hot-rodded your engine? Do you have a stock SPICA airbox or do you have an 'open' type air filter system on your intake manifold? If any of the above is true, you may need a custom radiator or more efficient cooling fans. Often, when an Alfa engine is modified for more power, people forget to give it better cooling. A 'rough' guess is that for every 10 HP gain, you will see about a 10 degree climb in temperature - if you don't improve your cooling system to go along with your modifications.

Cheers,
 

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Hey Jim:

Don't know for sure on the 79 if it has a return restrictor.....but my 78 does so more than likely so does the 79. And if that is removed it could be the culprit.

Hey Sarah:

If the fan is working and you can feel the air its pushing/pulling .....that should be more than enough. I use a pusher fan on the front side of the radiator (bumper side) and it makes quite a breeze. You can pick one of those up at autozone with a control thermostat for around $100 if you feel your electric is not getting the job done. Got to remember that stock it was just a 5 or 6 blade plastic fan w/ a shroud. Electric would certainly out pace the stock at idle. And you really don't need a fan running at highway speed. Are you sure that the temp sensor is correct if you are still reading hot? What is the temp at going down the road now and what is it at idle now. Also, double check the radiator as AlfaJim stated and make sure there are no cool spots. Even though its been to the radiator shop, perhaps they missed some blockage.

Hey Alex:

I have all the mods you referred to and from my experience w/ a stock radiator and electric fan I don't run hot. I usually idle in traffic at around 190-195 and no higher and drop down to 180-185 going down the highway. But having a good radiator is key. I probably get it a little cooler running a 160 thermostat, but the temp she is at now is pretty good. Anyway, if you are over this way, I will take you for that ride and try to scare you. You know in KY we like to play "Duke Boys" and jump ditches.

Best Regards,
John M
 

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John,

Jumping ditches in Kentucky with an Alfa Spider? OK...whatever turns your crank, I guess!

I used to ice-race a mini cooper with no windows in 20 below zero weather! Now THAT gave a whole new meaning to the term "Redneck"!!!

Of course, we used to say "Radiator!?!? We don't need no stinkin' radiator!"
 

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I just solved a similar problem with a 3 row row raditor recore of the stock radiator and a 11 inch electric fan. I put the thermostat back in(185) and it hasn't moved off of 185 since, and I have a highly modified engine. also, I've found that a small block chevy thermostat works perfectly but this should be no secret to those who have been around. I hope this helps, Bill
 

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Hey Alex:

Your ice racing story reminded me of when I first got my spider and I was driving her down to western KY to the body shop in the middle of January. Three hour trip in the dark. Old cloth top had literally ripped off in December. Car had sat for like 8 years before I got hold of her. Top was rotten. Rockers needing replacement. I drove that car down to the shop with three coats (one was my trusty USAFA parka) on and still froze my a$$ off.

I guess this story demonstrates how a true redneck saves $60. I don't know why I just didn't rent a uhaul trailer and tow her down in warmth.

Yee Haw!

Luke Duke
 

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Do you know what kind of fan you have? Is it an Alfa fan that was designed for A/C or an aftermarket one like a Hayden?

If it's the Alfa one, then it may not be enough air...

To share my similar experience- I have a '73 GTV, which is basically the same (SPICA, was mechanical fan...). When I first got it, it was ok, no fan shroud but the big 2.0l fan seemed to pull enough air via the water pump.

But, naturally, I wanted more power, so I converted the large fan to a smaller 1600 fan. Still no fan shroud. When sitting still, this would give me some headaches just like you say- it would overheat something terrible. And was VERY difficult to restart.

The partial solution was to install a proper shroud, which basically took care of the issue, 80%.

When I had the engine rebuilt, then I had the radiator re-built, and the engine was all cleaned out as well. That was 100%. Never overheated at all.

But I wanted more power. So I switched to a Hayden electric fan- which I bet is what you have. So all of the above is not much help...

One thing I've noted about my car, when I autocross, I HAVE to run the fan to avoid overheating. As well as running on slower tracks like Waterford Hills. Big, fast, ones like Gingerman or Nashville, I can keep the fan off, and the water stays at 175 deg all the time.

When you had the radiator flushed, did you have the same done to the engine? When I went over another motor, there was a lot of curd at the bottom of the block near the liners. I found it very easy to clean out....

Eric
 

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Over the last evening, I thought of something else-

But first, what changed since you've noticed the overheating starting?

Anyway, on our '78 Spider Challege car, I've noticed that on either side of the radiator, the opening is pretty big, which runs the risk of air re-circulating on itself.

Question for non modified Spiders- along the driver's side, it there a large gap between the radiator and the rest of the car?

Perhaps if you experimented with something to block the air through that point, you might find something??

Eric
 

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Discussion Starter #13
You know my memory is a little foggy on what was going on before radiator was recored, but when I got it back I became more aware of the water temp and perhaps then is when I noticed that it was getting pretty hot - but it is when it would get hot enough to restrict the fuel flow and start to idle funny then stall in stop and go traffic ( I'm going to vote it's the worst in the world but I'm sure I'd get arguments) that I REALLY started pay attention. The engine has been pretty well modified (no weber carbs - well... not yet at least) and one of the currnet theories is that the electric fan is just not substantial enough. Where it is, I can't get a good look at it, but I am thinking a stronger fan might be a help. (it is in FRONT of the rad. but blowing through it and not put in backwards at least) The fan does go on automatically when car reaches a preset temp, and runs for about a minute after car is shut off, but I can feel the heat in the car as well when the engine starts getting too hot.

I'm going to play around with it next week and look at some of the things you guys have been so kind to mention/ suggest above (providing I can get a little time when it is NOT raining- should have bought an ark...)
and see what is what. Hopefully I'll get this thing licked before the REAL weather gets here.

Sarah.
 

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Discussion Starter #15
It seems Alfa Jim is right about the Thermostatic Actuator. It overheated on the first hot day we've had and went up to 235-240 degrees which caused the TA thingy (I'm so damned techincal!) to stop feeding the car gas. The car started not to get enough gas and then just out and out died. I waited 25 minutes for the car to cool off and it started again, but made me really late to work and people on 37th st. heard words that nice girls don't say.

I have the Alfa disease, but I'm starting to wish I picked something a little less frustrating like knitting.... okay that would last a whopping 3 seconds, before I got car crazy again, but I can dream.

Sarah.
 

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Ah yes, the infamous SPICA frustration! All SPICA owners curse their system once in a while...until they get to know it and work with it...then some even learn to love it!

I myself, prefer carbs, single-point ignitions and mechanical fuel pumps...but then, I have simple tastes. Getting to work on time being one of them;)
 

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I'm starting to like my spica, and all I've ever touched was the idle intake.
 

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I made a custom contraption to fix the problem. idles at 700rpm now.
 
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