HELP!! 308 Overheating

Hello -- first, please note that I know there are many threads on this topic and I have read some but I need help figuring out what's going on here and I need a quick fix for the weekend until I can get it to a mechanic. I'm in NYC and this has been posted there too, but I wanted to put it here as well to see if I can get some more immediate advice. Please keep in mind that I am very much a rookie, this is my first Ferrari, and I am not technically capable of fixing much. That said, ANY helpful response to the below would be appreciated!!

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Well, wouldn't you know it, the same day I get my pics of my new baby up here, I have a problem, and I may not be able to make the Hospital run (NYC, this Sunday)... So, for anyone who has time to read this long message and maybe help me out (with thanks to Clyde for reading this twice) here's the deal:

I took out my '84 QV tonight (Friday night) and, within 3 blocks of the garage, the water temp skyrocketed right to the high 250 mark, and the car was very obviously running really hot. I got pretty freaked out and drove it right back. I noticed the engine was smoking a bit when I parked and turned it off, and there was a strong smell of something burning (the guys in the garage thought there was a fire someplace from the smell!) The car wasn't on fire, of course, but this really worries me.

Here's the relevant background: I bought the car a little over a week ago. During the PPI, when the guy drove it and was coming back into the garage, there was a line of coolant leaking on the floor. The former owner explained that the coolant was overflowing a bit because it had been overfilled. The guy doing the PPI took note but didn't seem worried about anything. When I picked up the car a couple days later (last Thursday), I drove around (often in traffic) for a couple hours and everything was basically fine. The car got hot but it was gradual, not sudden and immediate. When I parked it that day, though, I did notice the same "smoking" and some more coolant on the ground, down beneath the rear left (driver-side) wheel, where there was also a pretty strong jet of steam (I think) coming out. I called the former owner, he assured me it was just the coolant acting up again. I didn't drive the car again until today, and it clearly nearly overheated today (it took a couple of hours with the car off of course for it to cool down).

Clearly, something is not right. From my limited knowledge, I would guess the two most obvious/likely problems are (a) a loss of coolant due to a hole or break in a hose or (b) a bad water pump. I'm sure there are other possible explanations, and I'm afraid it's something big. I JUST got the car and really really want to make the hospital run this Sunday, but unless I fix this problem today (i.e. Saturday), I can't drive the car!

This is causing me a lot of stress, especially because I don't have the experience or ability to fix much myself. My first step tomorrow is going to be to take a look at the radiator and see if I need to add some antifreeze. I'm reviewing my manual now to try to learn about this, but frankly it's not that helpful. I've started reading threads on FChat about 308 overheating but most of the threads seem to be about long term, preventive solutions (new water pump, new fans, better thermo etc.) What I need right now is immediate help figuring out what is going on, first, and then how to get by long enough to take it someplace for long-term improvements.



Thanks all...

 

My guess is that if they had just changed the antifreeze it may have some air in the cooling system. Something you could try yourself is to bleed the radiator. First take off the coolant fill cap. The fill is at the reservoir can behind the engine, there is no fill at the actual radiator. Check the level, add some if it is low, leave the cap off. Then, on the passenger side of the radiator, forward of the spare tire, near the top, you will see a small knurled nut. That's the bleeder screw. Open that up a few turns, it doesn't need to be removed, just opened up a bit. You will need a pair of pliers. You should get straight coolant coming out. If you get any air, just leave it open until all the air is out. When it is all coolant, snug it back up.

There is also a bleeder screw on top of the engine, also on the passenger side, on top of the thermostat housing; it looks like a brass bolt. check that one also for air and then top off the coolant. The side of the reservoir has markings to indicate where the level should be. Roughly 1/2 to 2/3's full. Put the cap back on. Next to the cap you will see a small clear plastic hose that runs down. This is where you saw that jet of steam coming out. When the coolant is overfull or the system pressure gets too high due to overheating, it will burp out the excess through this hose. The burning smell was probably just coolant splashing onto the exhaust.

Next would be to check the cooling fans. Just start the car up and let it warm up in the driveway. When the car gets up to around 190° or so you should hear the fans come on. It should take around 15-20 minutes or so depending on the outside temperature. If the fans don't come on check the fuses. The fuse panel is behind the lower portion of the dashboard on the passenger side. That whole portion of the dashboard is just a cover.

If you've got all the air out of the system, the coolant topped off, the fans come on and it doesn't overheat in the driveway - Go ahead and take it for a spin keeping an eye on the temp.

Good luck! If the temps stay normal then it was just air in the system and you have just completed your first Ferrari repair.

 

Pete nice description. Also he might want to make sure that the water pump belt is turning and possibly want to get a new rad. cap but I assume it was not overheating before he got the car. Enjoy the ride.

 

I am chasing a running warm condition on one of my 308s as well. I have repaired almost each one of my 308s from running hot before. It can be a pain.

Check for obvious leaks or obsrtuctions in airflow. If you have a leak find it and repair it. If you can't seem to find it rent a cooling system pressure test kit at Autozone or Advance Auto. Pump it up to pressure and find the leak.

First I would replace the radiator cap. Cheap and easy to do. Get a 1.1 Bar cap.

I would pull the thermostat and put it in a pot and heat it up. Make sure it opens. If you don't want to remove it then you can run the car and make sure the radiator get hots. You can also feel the top hose pulsate slightly when pressure is applied after the thermostat has opened.

Make sure the cooling system is bled properly. Air in the system will cause fast temp spikes. The temp gauge will go from 195 up to 230 quickly and then back down if there is air in the system.

Water pump. Easy to check. With the radiator cap off on the header tank start the car and watch in the tank. You should see a steady stream of water coming in the header tank. Rev the engine slightly and make sure you see the increase of water flow.

Belt and water pump rotation. With the car running look at the water pump and water pump belt. Make sure both are rotating correctly. If you feel you can see the tensioner pulley moving mark the top of it with some white paint when the car isn't running and restart it and recheck.

Now onto front radiator fans. The best way to test this is to remove the 2 wires on the radiator fan switch. It is on the passenger's side of the car at the bottom of the radiator next to a coolant hose. You will see 2 spade electrical connections on it. Remove them and attached the 2 wires together with a jumper. Turn the key to the 2nd position. The fans should come on. Both of them.
Now check to make sure they are blowing accross the radiator. It is important that the fans are turning the correct way.

If all of this checks out you either have a bad sending unit or coolant temp gauge or the radiator is clogged. You can check the radiator by getting an infrared temp gun and shoot temps at the radiator inlet and outlet. You should see a 25-30 deg. drop in temps between the to readings.

Anyway this should help you out. If you need more detail on the gauge or sending unit let me know. I have yet to see a bad sending unit but I have heard of them going out.

 

This sounds very similar to what was happening to my 328 last year. Basically the rocketing temperature was caused by a loss of coolant which in turn was caused by a weak cap on the expansion tank.

Suggest you get the cap tested & if its not holding at least 1 Bar then that's probably your problem. You should be able to get a standard 1 bar cap that will fit at your local auto parts store.

Once you rule the cap out (i.e. if replacing it doesn't solve the problem) then I'm afraid you are looking at water pump or radiator problems - but I'll bet you its just the cap - they don't last more than a few years at best.

The coolant level in the tank should be 6cm below the bottom of the filler neck i.e. the tank should only be about half full when its cold. As others have said, bleed from the radiator and the thermostat housing to eliminate the air and expect to get several lots of air out of the system. Make sure your heaters are working.

HTH

I.

 

Very good description guy's,
but don't for get to open the heater switch inside the car so that the water flow is not blockt.Rob

 

Rob makes a great point. Don't forget to open the heaters when bleeding.

 

So Jawad,
I'm kind of curious as to what you found out today.

 

I second the bleeding and the radiator cap. The previous owner of the first 308 I bought spent a lot of money on the cooling system trying to cure overheating before he discovered the cap was bad. I had a similar problem with the an 85 QV I owned later, so bought a new cap. Since I was thinking of showing the car, I bought a Ferrari cap but the problem continued. Eventually, we tested the new cap and it was bad. So, do not buy a Ferrari cap. Bring the cap you have to a Nappa store, tell them you need one with 1.1 bar or so. I believe there is a BMW cap that matches perfectly. Anyway, a bad cap causes all kinds of problems. Without pressure, the water boils at a much lower temp, doesn't flow right and heats up more quickly. The smoke and smell you got was probably from antifreeze on the exhaust.

Dave

 

these cars are old and the hoses are old and with engine off and cold look at every hose and squeeze and see if puffed out or feels spongy...with engine hot and running...look for drips, smoke hissing...take your time and a flashlight and look,look, look....on three seperate trips out to the hamptons with a girl I blew a rad hose sitting in GCP traffic....not fun..and not a smart way to go about replacing your hoses..pressure test the system..the expansion tanks are very old and can get pinhole leaks...I had mine "resealed" many times and there can still be problems. hot steam and fluid shooting out by the rear drivers tire (LHD) is overflow from the expansion tank...tank when cold should have a level about 6 cm from top...no more..or it will boil over, smoke and spit it out. bleed the thing or air..there is a bleed screw onthe rad and also on the thermostat housing...let lots of coolant "piss" out of those holes....
BTW// where are you parking her and what is her colors? Welcome to NYC Ferrari ownership....hang on tight!

 

Thank you to all of you who posted advice in repsonse to my message. I read all of your posts and talked to some other people as well (including John Turrell in MA and, later, Doug Pirrone in LI (NY), who, for the record, were extremely kind and helpful), and basically followed the instructions and, so far, think I fixed the immediate problem.

First, I checked the coolant and discovered that it was essentially empty. Though the prior owner said he had over-filled it, I think it all blew out. So, I refilled the coolant (a bit too much but let some of it drain through the overflow), as a first step. I looked at the water pump belts and they seemed fine -- they were still on the pulleys and seemed to have sufficient tension and weren't visibly wobbly when the car was on. After this, I opened the thumb screw on the top right of the radiator to bleed any air out of the system (first I did it while the car was off, then I did it again with the car on and the heaters running). Each time, coolant came out immediately. This could mean there was no air in the system, or, quite the opposite, that there was some air trapped behind the coolant, I'm told. Anyway, I eventually got a good, steady stream of coolant out of the bleed, so figured I had probably purged any air that might have been in the system.

Last, I checked to see whether the fans were coming on and I believe they are when the water temp gets to just under 195c. I noticed that one of the radiator fans wasn't running when I had the car on and the heater on, but I got two different opinions on this. One person told me that this was normal but that both fans should come on automatically (assuming the thermostat was working properly and there was no blockage preventing coolant from flowing to the radiator) when the thermostat triggered as the car got warm. Another person said the fan could be a problem (for which I should check the fuse first, then the relay then, lastly, the fan itself).

After replenishing the coolant, checking the belts (and overflow hose) and bleeding the radiator, the car ran just fine in traffic and on the highway for hours. The water temp stayed just under 195c, at low or high RPM, heaters on or off. There was no more burning smell, and, aside from just a bit more coolant coming out of the overflow hose, no visible leaking.

That said, I think I will follow all the valuable advice and do a few more things, like replace the cap with a new one (which can't hurt), check the fuses and the thermostat and having someone look at it the car more thoroughly.

Again, thank you all. FChat is truly a great place to learn about these cars and you were all very kind to take time out to give me advice. For those of you in NYC, see you Sunday morning at the Hospital run.

Drive safe and happy!

J.