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Discussion Starter #1 (Edited)
I’ve been trying to solve the overheating that just started in my ‘82 Spider. Tested the thermostat and found it starts to open at about 178F, fully by 200F. Check hoses for blockages, put in a new rad (needed it anyway), cleaned out reservoir, no leaks, until it starts blowing through the reservoir. Pump isnt noisy nor leaking, no metal shavings in the reservoir (impeller failure).
Could the pump have failed even without noise or leak? Head gasket?
Any advice from the experts?
 

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Open the coolant cap while the engine in warming up to see if there is any combustion gases getting in the coolant passages, a leak down test would also show this too.

Opening the coolant cap during warm up might show you still have air in the system too.

Running lean can cause it, how do your sparkplugs look?

Compare your temp gauge readings with a lazor heat temp gun next to the sensor, maybe your sensor is going out?

Clean the electrical connections to the sensor, check the ohms of the sensor to see if it falls within spec's.

Do a pressure check on the coolant system.
 

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The 2L engine needs to have the cooling system bled to remove trapped air. There is a bleed screw (brass bolt) on top of the intake. There is a coolant hose attached to each side. Loosen the bleed screw as the engine is warming up. After a few minutes (or less) all air will have escaped and only coolant will come out (have a rag handy...)

There is also a bleed screw on the water pump.. That one should be open during initial filling - don't try to access it with the engine runny (otherwise we'll be calling you Lefty...)!

1606401
 

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Discussion Starter #4
I’ll do another bleed of the system. I did have the bleed screw on the pump open during filling, and then the one on the thermostat. But will try again, since i need to transfer coolant from the reservoir back to the rad.
if that fails, i’ll go through the items from msiert.
 

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Make sure the hose from the radiator to the reservoir is in good condition. I have seen cases where small splits will allow coolant to go from the radiator to the reservoir (as is normal as the coolant warms up) but then it sucks air when it cools down - instead of drawing coolant back into the radiator. Also, a faulty radiator cap can cause the same problem. After a few cycles of this 'one way' fault the radiator is low on coolant leading to overheating (even though the reservoir is full or even over full).

The one worrisome clue is where you mentioned it 'blowing through the reservoir'. It should not do this. Checking for combustion gases as 'msiert' suggests is a vital step. A failed head gasket could cause the issues you are having...
 

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Discussion Starter #6
Well, Eric, i think ive confirmed it is indeed a head gasket:

  • transferred coolant back from the reservoir to the rad
  • bled the coolant system at the pump and upper bleed screw
  • started the engine body with rad cap off and immediately the rad over flowed...engine running rough.
  • checked the dip stick and oil cap, and found foam and runny oil.
so i think means the head gasket failed inwards to the engine.

does that sound right? Now to contemplate next steps. Im not afraid to tackle it. Just need to get the plan together.
 

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Well, do you know any Italian swears? (don't forget the proper hand motions)

It does sound like a failed head gasket. A leak down test would confirm it but what you describe is plenty enough to diagnose it. Do not run the engine if there is any possibility of coolant in the oil. The coolant/water will not lube the bearings and can ruin them in short order.

The Alfa engine has wet liners. At the very bottom is a thin rubber O-ring to seal the bottom of the cooling jacket from the sump. If you are not planning to replace those O-rings it is important that you do not disturb the liners. They are usually well & truly stuck but, as luck may have it, if you were to turn the crankshaft with the head removed you might push a liner up and ruin that O-ring's seal. The best practice is to fashion a liner hold down. Of course there is a special Alfa tool but you can easily make one with a fender washer & a tube that fits over the head stud. The fender washer fits over the edge of a liner, the tube is so a head nut can clamp it all down.
 

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Discussion Starter #8
Ya, i know few words, having lived in Europe a few years, my wife says I’ll need to sound- insulate the garage before i start on this project!
Thanks for the tip.I’ll be sure to block the liners when the time comes. I read through Vin’s “Head Gasket Replacement For Dummies” thread, which looks like a good guide. I did one years ago in high school auto shop, so some memories might return if i still have those brain cells!
 

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If you have coolant coming out under pressure into the over flow bottle. You have a blown head gasket. Its pushing combustion gases into the cooling system. I've seen a tech get burned when one blew a hose and showered him in very hot coolant.
 

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Be a perfect time to do a valve job!

If your going to pull and reinstall the head yourself that's the expensive part with the labor rates over $100 an hour! I don't think I would trust myself to get the cam timing right.
 

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Head removal is straight forward. With a carb motor and two people working together it is no more than 1 hour and could be 30 minutes if everything goes smoothly. It may be a bit longer for you depending on how much of the intake and fuel injection stuff has to be disconnected. After replacing the head be sure to turn the engine over a couple of revolutions by hand to be sure the valve timing is OK before you hit the starter.

When you have the head out and with cams installed, do not lay the head down on a flat surface or you may bend the valves!

Do not rotate the crank while the head is off unless you are using something to prevent the sleeves from lifting.
 

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What fan are you running? the PO had an underpowered elec fan on my car when I got it and I battled over heating issues. Had the radiator overhauled, new thermostat - still the same. I got rid of the fan and replaced with the fan blade bolted to the pulley and put the shroud back on - fixed. I have an 83 spider.
 

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Discussion Starter #13
Thanks all for the tips.
Phil, my ‘82 has the fan on the pully, and the electric fan for the A/C condenser. Head Gasket - here i come!!
First, get my gasket set coming.
 

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Discussion Starter #15
If i find anything different from Vintre’s step by step thread, i’ll post with pics. Bought the Reinz head gasket set from Spruell...step one complete.
 

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As someone who did their first Alfa spider head gasket job just a few months ago, I think its safe to say you are in for a treat. Its very straightforward, borderline simple.
Biggest enemy is rusted and stuck bolts.
Do yourself a favor and use copper grease on the applicable bolts when you put it all back together, you or the next owner will certainly appreciate it !!

Cam timing isn't that bad but can be time consuming the first time.

Take lots of pictures of what you're taking off so you can see where it goes back too!
I put all of my parts into baggies with labels so I knew exactly what they belonged too, and to keep from any nuts or bolts from walking away when I wasn't looking.
 
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