All, Hoping you cal help me understand what happens when I get water coming out of the hose (cap) on the expansion tank. I've was told by my shop this is normal but I just don't understand what is happening? Tonight I took her out to the store, about 5 miles away, city driving. Gauges were normal, and it was in the 50-60's here. When I come out of the store, I see a small (silver dollar) sized puddle under the car, coming from the hose that leads up to the expansion tank cap. I realize this question and answer has probably been posted a hundred times here but I must not be searching for the correct phrase to get the answer I am looking for. I assume this is, in fact, normal and I simply need to check the fluid level every so often. I'm just trying to understand what is happening here. Appreciate the feedback. Craig
It is really only normal if the water is over filled. It should get to a point of equalibrium and stop. Or like the other post, the cap can be bad.
My bad, I neglected to mention that I replaced the cap (new 13lb cap) the first time it happened. The tank is about 60% full.
I KNOW it sounds silly, but, nevertheless...this happens also from time to time! Has your coolant been replaced recently? If so, are you sure that the heaters circuits has also been fully bled and then opened back to new coolant, before the shop pronounced the car ready? Sometime air accumulates in the heaters circuit and stay there if these are closed, only to release bubbles in the main coolant circuit when the heaters are turned on for the first time after the coolant replacement. These air bubbles may then provoke overflow as described. If not, check your cap; I know some people replace the OEM 0,9 bar with a 1,1, but I did it with a brand new 0,9 bars, thinking that the systeme has been designed to function under 0,9. Overflow stopped immediately. Rgds,
I've tried with new .9 and 1.1 Ferrari caps, but didn't solve the overflow problem until I started using a Pep Boys cap! And the coolant has been flushed/filled every two years for the last twelve years...
You really shouldn't have any "routine" coolant puddle under the car. Be sure that you've fully bled the air out of your system (with the heater water valves open - full hot) and don't overfill the expansion tank. I keep my coolant about 1" below the filler neck and have bled it and never have the car tossing coolant, no matter how long the drive. My cap continues to be OEM spec, purchased from Superformance UK. I purchased a new thermostat from them this year as well (OEM spec). I did also install an Aladdin auto-vent on my '85 QV's radiator bleed, it's done the job really well. Once all of the hoses are replaced, I will be leaving it there....there's really no downside to it. http://www.ferrarichat.com/forum/showthread.php?t=373050&highlight=aladdin If you're unsure of the age or condition of your hoses (especially the top-end hoses that run under the plenum), it would also be good to get in there at some point and replace them. It's on my short list. The smaller hoses and fittings up there can get gummed up.
I'm in the "stick with an OEM 0.9bar cap" camp. If you just put a higher pressure cap on to cover up an overflow issue, you're moving the pressure elsewhere in the system, waiting for the next weakest point to fail. They aren't expensive or difficult to find, and they will not normally leak if everything is working correctly. Note as far as I know the Superformance cap is the newer 1.1bar one, safe to assume that unless a cap is specifically marked for sale as a 0.9bar.
I would say go with it and see if there comes a point where it stops doing it. Just check it after every drive (after its cooled down obviously!). Also check the radiator bleed. If it keeps doing it right down to where the tank is obviously nearly empty then I think you'd need to look at what was pressurising the system The manual says the level sould be 6cm below the top of the filler neck but my car will toss out coolant when that full. Mine seems to like the tank to be a bit under half full & once it gets there it stops throwing the stuff out & everything is happy. ETA I think the short route to checking this is also just to bleed the system & then leave the car running & let the temp climb till the fans come on , & let them cycle on & off a couple of times & see what, if anything, comes out by the rear wheel. Collect it in a container & see if it stops - you will know how much you had in the tank to start with & therefore at what point its clearly not going to stop! At which point you abandon the test when you feel you have lost more than an acceptable amount. If it does stop then turn it off & let it sit & see what happens & if any more comes out. If you get no more then let it cool down & see what's left in the tank. As long as its about 1/3 full then I wouldn't worry about it , but by all means repeat the test to be sure if you want & as long as you get nothing out on the second test then I'd say you don't have a problem & you have found the level it wants to be at. If the level in the tank actually seems surprisingly high after the test & after its lost some coolant then you probably have air in the radiator, so bleed it out & see what's left in the tank after that.
There were some problems with my expansion tank last year - some coolant did overflow. The expansion tank had some loose paint on top of the filler neck and inside it where the cap seals. A good thing is to clean and remove all loose paint and dirt from the filler neck where the cap rubber gasket comes into contact. It might be the case that the cap is not sealing up to 0.9 bars .. then it does not matter much if it is a 0.9 or a 1.1 cap. They might not seal at all, or just barely. Anyway, after cleaning up, all is well - no coolant overflow.
Added a overflow tank to my system and filled the expansion tank to the top. Never had an overflow problem again, and don't have to burp the radiator.
"Mine seems to like the tank to be a bit under half full & once it gets there it stops throwing the stuff out & everything is happy" My 328 is the same. If you overfill it it will spit after every ride until it reaches that point. I don't worry about trying to get it exactly right when I change coolant. I just fill it to a bit over 1/2 full and let the system spit it out until it decides it's at the "correct" level. But assuming the system is ok, it WILL quit doing it and maintain the normal level from that point on until the next coolant change.
It's funny because when I tried to upgrade my .9bar cap to 1.1. bar, not that there's anything wrong with the ,9bar, I just want to upgrade, the coolant start to come out of the overflow hose of the expansion tank everytime I go for a long drive. After a few months of not able to figure out why, I switch back the .9 cap and the problem never came back. So I guess I might have gotten a new but bad 1.1bar cap.
I can confirm that after coolant change/top up my gt4 does the same until the header tank level drops just below half way, then it stops.
Thats what you get for using those crap Italian radiator caps. I gave up on that junk 20 years ago and forbid their use at my last dealer. Far too many comebacks due to a 30 dollar cap when a 10 dollar Stant is perfect and will outlast any of these cars.
All, This discussion has been very helpful, thank you. One of the things I had never done (as was suggested here) was to let the vehicle come to temperature and turn on both heater valves up high. Now that I've done that, it does not appear to be spitting up anymore. Thanks again, Craig
Could you post info on what expansion tank you got(make/model, where to buy, price, etc.) ?? I'd like to add same to my 328... Saw a pic in a book/mag many years ago of a small white plastic expansion tank on a 308QV or 328 that was attached to the support rod that runs from the top of the engine back to the storage compartment. Looked good and very practical. Kinda surprised Ferrari never implemented something like this, as it would eliminate all concerns about overflow.
Just to keep the vernacular straight, I added a overflow tank (or fluid reservoir) to the expansion tank. Found one at NAPA (brand name Dorman) for about $6. Mounted mine where the air pump system was and wrapped it in Reflecix to keep the heat of the exhaust system from melting the nylon housing. Took the end of the drain hose from the expansion tank and attached it to the bottom of the overflow tank. Instead of spitting fluid to the ground, it puts it in the overflow tank. When the motor cools, it sucks the fluid back in to the expansion tank. This is a stock photo of the Dorman. Will see if I have any with it mounted to my car when I get home. I am planing on upgrading to a metal tank during the winter project. Image Unavailable, Please Login
Thanks for the overflow tank info. Will eventually get around to this and maybe go browsing on the web or at a local NAPA store.
It really shouldn't be necessary on a correctly functining 328 cooling system. If it won't stop throwing coolant out then you really need to find out why because with the correct cap & the right amount of coolant (and no air!) in the system it won't need an overflow tank.
Can not speak for the 328, but the 308's have always had a problem with air in the system. You are correct, if the system continues to throw out coolant then you have a problem. But what seems to be happening is it will purge enough to leave 1/2" to 1" of air at the top of the tank after cooling. Since the return line from the expansion tank is at the top where the air is left behind it will get sucked in to the system. A overflow tank seems to have eliminated this problem.
"Can not speak for the 328, but the 308's have always had a problem with air in the system." I believe the overflow tank just hides the problem... I'm confident that when people bought a new 308 in 19xx that they did not have to routinely take the car in to the local Ferrari dealer for service to let air out of the cooling system or install an overflow tank. I believe that this issue is simply due to age and leaks/seeps in the fittings/hoses/head gaskets, whatever. Aluminum parts/fittings can become porous/brittle if the coolant has not been regularly replaced or checked for proper chemical makeup. A pinhole in a fitting or at a hose junction can cause the problem without any coolant visibly leaking.
You are correct, they did not add an overflow tank to the system, but they did recommend the owner occasionally purge air from the system at the radiator. Your are also correct that over time the system can build up pin hole problems, and that adding a overflow tank will not solve these issues. But since I have added the overflow tank I have not had to burp the system. Which would indicate this car does not have leaks or it would still have air accumulating in the radiator. Also the car has not self destructed or ripped a hole in the time space continuum as a result of modifying the original design.
I understand that. I don't have any issues w/coolant overflowing; ever since I saw a pic in a book/mag showing a 308 w/tank I've wondered about adding that, but never got around to it. Just seemed like a good idea to me.
