328: Lost its cool? Or not?

An odd situation happened to me tonight. It is a cool, cloudy evening in Atlanta, and I decided to go to dinner at an Outback about 6 miles up the freeway from here. I knew there'd be some rush hour traffic, but in this area the traffic still moves about 25-30 MPH and I'd never had trouble with the car in that environment.

About halfway there, I see a little spray of fluid coming up over the front bumper, and then I see the water temp gauge (which had been normal to that point) gradually go up to about 240 degrees. There wasn't much I could do immediately because I was in the middle lane of a 5-lane roadway and my exit, the next one, was still about 2 miles off. I eased off the throttle and changed lanes to try to maintain airflow through the radiator. The engine still sounded fine and there were no peculiar smells (like antifreeze).

Mysteriously, the temp gauge dropped back to 195 (mid-gauge) and after about another mile, began going back up just as I reached the exit ramp. I gingerly drove the car to the restaurant with the gauge getting back up to 240. When I shut the car down, I could see a bit of fluid dripping onto the front airdam. There was a bit of steam coming from the engine bay, though that had stopped by the time I opened the engine cover to take a look. The engine was putting off a lot of heat (especially for a 6-mile drive) but there was nothing dripping below it and, again, no unusual smells.

When I was done dining, I asked for a bucket of water. I aimed to put water in the coolant tank to see if I could see anything leaking. I had planned to then walk to the nearby Target and buy some antifreeze, but when nothing seemed to leak, I elected to simply keep filling the coolant tank with water. The bucket was just the right size to completely fill the coolant tank, which obviously had been empty, or very close to empty. I started the engine, and everything seemed normal, so I returned the bucket to the hostess and drove the car home. The temperature remained normal throughout, the engine behaved just fine, and there is nothing leaking on my garage floor.

The only thing seemingly wrong now is that I have a car whose cooling system is filled with water instead of the 50/50 mix. Tomorrow, I will check the coolant level and if it is still normal, I will drive the car to a shop and have the cooling system drained and refilled.

Can anyone surmise what happened? Do I have a very slow leak somewhere that had gradually let the coolant drain out? (I never noticed any leakage in the garage, and the water temp had always run normal until tonight.)

 

Here's my guess--if you didn't say that you saw a spray of liquid squirting from the front of the car and if the level were OK, I'd say that it could be a lot of air in the system. However, the spray and very low coolant level suggests a leak--likely in the radiator due to the location of the leak. You may have sprung a pinhole leak in the upper part of the radiator ( or something in that vacinity --such as upper hose) and it spewed out until the coolant level was low enough to not reach the hole anymore. This would account for the low coolant level and the end of the spewing.

Before refilling with 50/50, top off the system with water level , start the car and let it run to full operating temp. Watch for leaks as it runs. I bet you'll detect it that way. If you can't see where the leak is coming from that way, get a leak detection kit , ie coolant dye and a black light, and you will more easily see it that way.

 

That sounds like a reasonable theory and I'll test it. Does anyone know if radiator stop-leak can be used in a Ferrari of this vintage (1986)?

 

Sticky thermostat?

 

I wouldn't use a stop leak product.

A good radiator shop should be able to pressure test it for a minimal cost.

 

easiest way to find the leak without damaging the engine is with a pressure tester. You connect the apparatus to the filler and pump the handle. The engine should be cold. There's a gauge to show the pressure build-up. Even if you can't immediately see a leak you can see the pressure drop gradually if there is a leak.

Coolant system pressure tester should cost around £30 here in UK, probably cheaper in the 'states anyway.

 

I just reread the description of the problem and noted the "bit of steam rising from the engine bay". Although you had obvious leaking from the front of the car, I'd also look closely at all of the hoses/clamps in the engine bay as well. If coolant is squirting/leaking onto the hot exhaust, you could have a problem.

Does your car have the original hoses on it still? If so, it may be a good time to replace them. I have an '85 308 and had 2 hoses erupt last year--the heater hose at the engine juncture and one of those damned hoses under the intake plenum. With age, the hose exposed to the most heat break down the fastest.

 

That happens to me all the time, usually after a few days at the track. Evidently the 308 and 328 are known for this. After being driven for extended periods (especially at very high revs) the engine forces gas into the cooling system. There is a brass air valve on the top of your radiator you can use to bleed off the gases while the engine is still hot. Do NOT overtighten the valve, and be sure to wear gloves or use a rag as the steam is very hot. After bleeding the air you'd be amazed how much coolant you'll need to replace. If the engine is still warm be sure to keep it running while you slowly add your 50/50 mixture. I carry a bottle of coolant and a bottle of water with me to the track because by the end of the weekend I'll need to fill it again. This was demonstrated to me at Las Vegas Motor Speedway by the guy who owns the Motor Speedway in Dallas. Sorry I can't remember his name - what a great guy!

 

"I see a little spray of fluid coming up over the front bumper"

Jim, did you find the source of this leak yet? Hopefully it is just the air bleed or a hose going bad.If indeed you have a leak and need to drive the car to the shop loosen or remove the expansion/fill tank cap. This will keep pressure from building and you will only loose coolant thru evaporation, which is a lot slower than a leak. As long as the system is filled you should'nt have to worry about overheating unless there is another problem.

 

This one is an easy fix but takes a bit of time!.

I guarantee that one of the short black cooling flexibles (6 in the engine bay & 2 in the front at the rad are leaking). Most likley the connections under the engine where the pipes run to thew front.

The same happened to me, I suggest that you replace all your flexibles, I did not and I got a full system drop a few weeks later after a number of top ups!,

I coaught it just in time and did not do any damage.

The parts only cost 30 pounds streling in the UK.

A small price to pay!!! compared to a full rebuild if you miss it!

 

The cause of the sudden cooling loss last night remains unknown but it has not recurred. The technician suspects a hangup in the thermostat which caused coolant to be dumped overboard via the hose underneath the refill cap. For now I'm just going to keep an eye on it in case it recurs.

As for the spray, there is, as someone suggested, a pinhole leak near the top left corner of the radiator. A pressure check revealed a very small pressure drop, and I have not had to add anything to the coolant tank since last night. I drove the car to dinner in another county, and back--about 50 miles total, with no problems. The technician says that if I keep the coolant tank level full, the leak should not be a problem until I can get the radiator repaired.

Oh, and I had him check the potency of the coolant, considering the water I added last night. It is still quite adequate; he estimates about a 60/40 mixture. When I top off the tank, I'll do it with antifreeze, which should help bring the mixture closer to 50/50.

Thanks to all the FChatters for their suggestions!