Carrera51

My 944's radiator has had an intermittent slow leak for over a year. It doesn't even leak all of the time. Just a small spot on the driveway here and there, those spots have left quite a few stains on the driveway so I think its time to replace it.

I've been told to replace it with a 951 radiator. Is the 951 radiator bigger? Does it drop right in without any modifications? Any advice will be greatly appreciated.

RedlineMan

Well...

First, I'd be real certain it was the rad before I got into it. Might be easy to get fooled by something else. It is very uncommon for something to leak sporadically, especially a radiator. This is what makes me think I might not trust that diagnosis.

An infrared dye test would be a real good way of telling for sure. Genrally, I am inclined to wait until a leak becomes obvious before I really dive in too deep.

I don't know if a 951 rad will drop right in, but I don't really know why it would be necessary in the first place. First, you've got extra outlets to deal with. Second, the correct rad will work just fine if everything else in the system is up to snuff.

I guess you could do it, but I don't really see the point.

bearone

i had a small crack below the temp sending unit, could hardly see it and water never hit the ground but every few days the water level would get below the min line. ended up replacing the radiator.

Carrera51

Thanks everyone for your responses. The mechanic said its the radiator. The waterpump, hoses, and radiator cap have all been replaced. It tends to leak after being driven. If I pop the hood and losen the radiator cap to relieve the pressure after driving it, it doesn't leak. Of course, I tighten the cap back up before closing the hood. When it does leak it, always seems to be in my driveway, which has a slight incline.

If I replace it, I'll just get a stock radiator for it based on RedlineMan's recommendation.

newoldguy

No need to replace. Remove and take it to a radiator shop. Have them solder where its leaking and you're back to a dry driveway again.

josephsc

I guess you're not going that route anymore, but it won't just drop in -- you'll need to get someone to do some cutting for you, which I'm sure your mechanic will be more than happy to do....

Matt Marks

Mark,

Did you try this? Does anyone have any pictures of a completed upgrade? My 968 engine REALLY puts a strain on the NA radiator on the track.

Matt

83na944

Uhh, my 83 has a plastic & aluminum radiator. If this is true of you 86, you can't solder it and glue won't work either. No option but to replace it.

Some people sell a copper replacement that can be repaired, but it costs about twice as much as the original.

If you're really only worried about the stains on your driveway, you might go to AutoZone or NAPA and buy one of those large "cookie sheet" pans to place under a car. Throw in a little kitty litter, and the drips will be absorbed and the driveway will be clean.

Matt Marks

Oops - meant to upgrade the radiator to the turbo one, not to patch it. Apologies for not being clear

Jay W

I have had two separate porsche radiators leak in a very slow manner from the screw in hose nipple right above the temperature sensor on the drivers side of the car. If the antifreeze is leaking on that side, check to see if it is coming from where the nipple screws in. Mine had come loose and all I did is put a wrench on it an tighten it. But be careful because the wrench that fits it is an 18 or 19mm and the torque on the nipple is very low because it is all plastic. Just tighten it very slightly. It can break pretty easily. Take a look, it may save you several hundred dollars.

helzerr

My '87 NA radiator leaked intermittantly under pressure. It was leaking where the plastic tank is crimped to the aluminum core. At first, the radiator shop said there was no choice but to replace it. I did some more searching and found some repair crimp strips that crimp over the existing aluminum crimps. No leaks 4 years later.

951Porschiste

The 951 rad is bigger. Not a direct fit. There is no need to go that route unless you really, really, really, really like to mod your car

seb928s

No need for the 951 radiator you do just fine cooling with the 944 one. Plus it's just going to be a pain because it is bigger and it won't fit right in. Unless you have really made a killer 944 na then you really don't need the radiator. Keep the belts tension right and make sure everything on the cooling system is working right and you won't overheat.

Matt Marks

I've got a 968 engine in my 944S - temp regularly runs at the 2/3rd's mark on warm days at the track.

Hence the need to upgrade.

Nobody's done this? What about you guys who've put turbos in their NA's or supercharged?

Alternatively, does anyone have the physical measurements on an NA radiator and a Turbo/Turbo S radiator so I can do some planning? I haven't pulled my current radiator and the turbo S one hasn't arrived yet.

Thanks!

Matt