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996.1/.2 expansion tank differences

UncleP

Well-known member
Joined
27 Feb 2019
Messages
580
Wondering if anyone can tell me the difference between the pre 2001 3.4 expansion tank and the post 2001 3.6 expansion tank (apart from the massive price difference)?

Searching here I read that a few people with 2001 3.4s seem to have the later tank (they also noted the electric frunk/boot release which my car has). My car is registered as a 2001 but I believe it was built December 2000 so I guess this could go either way for me.

Searching for visual clues in determining which tank I have it looks like the early ones are shorter with a square back and the later ones have a long triangular back. Are there any other differences? I read a comment about pipe fittings being different but can't find details on this or see a difference in images.

Part numbers I'm looking at are:
996 106 14756 early tank
996 106 15704 later tank
 
There are 3 coolant tanks for the 996 .. 2 of which have a different support plate.

I'm afraid i don't know the actual differences but a rule of thumb .. if the part number is different then there IS a difference .

You need to look at the chassis number to get your model year ..

Wp0zzz 99z ( model number ) xyz .

Yours will probably be a 2001 model if registered late 2000.

ref parts here ...

https://www.deroure.com/diagrams.asp?MAK=3&MDL=25&TBL=2531&SMA=&SMO=0&ST=&SC=0
 
Much appreciated deMort.

I did see a version of the newer tank with a 3 at the end rather than a 4 so I figure that may Be the 3rd version.

I've spotted a few visual differences that can be seen without stripping the tank out and it looks like I have the horribly over priced one. That's the bad news. The good news is that I've fixed the leaky cap following your advice on another thread.
 
if you have a 2001 car then its £72 ...

if you have a 2000 car then its £203 on that site i listed ..

Your car is a 2001 ?

Pm me the chassis number if you wish and ill check the model year .
 
PMd you my chassis number.

I tried one of the online decoders and it says it's a 2001 model. Delivered to the dealer 20 Jan 01.

The expansion tank was replaced with a pattern part before I got the car. Seems the threads have gone so it just keeps popping the cap. It does look to be the early tank with the hose clips directly above the fuel filter holder.
 
I answered via pm but to share my comment as is right ..

That is a 2001 model so you would order for that year .. i think perhaps the best way forward ..

Phone your local OPC , give the chassis number to the parts guy and he will look up the tank and give you a cost for it .. you just say thanks and can i have the part number ..

That way you will know for sure as all these parts are found via the chassis number.

As far as i can tell though you have the cheaper one fitted .. i checked on ecp .. not very cheap from there but again the early car is listed as the more expensive of the two .
 
Took your advice and called the parts man at Glasgow OPC. Cross checking my chassis number it's come back with the newer/cheaper tank (part no 99610615704)

It does look like someone has fitted a pattern old style tank in my car. Porsche are certain it should be the part no above. For sale of saving £15 I just ordered the tank and cap from them.

Thanks for your helpful advice.
 
Just capping this thread off for others future reference.

I successfully fitted the new tank today. I have no idea if this is the style of tank my car left the factory with. All I know is that it's now in there and doing it's job albeit with a bit of a hobo fuel filter bracket (cable ties and jubilees).

Here's what I have learned about the expansion tank

3.4s have a short tank with a fuel filter bracket on the side. Only the C4s use this bracket. C2 the filter is under the car where the axle runs on the C4.

The later 3.6 style tank is longer with a triangle bracket on the side that attaches fuel lines. This is due to the 3.6s having a fuel filter in the tank.

Other differences are the position of the level sensor (side on the 3.6 tank and bottom on 3.4). The return pipe position (roughly 45° difference).

I have no way of knowing what my car left the factory with. I suspect it was the old style tank. Possibly one of the last ones left on the shelf. If this was the case then it seems you can replace your leaking £450 3.4 tank with an £80 3.6 tank.
 
UncleP said:
Just capping this thread off for others future reference.

I successfully fitted the new tank today. I have no idea if this is the style of tank my car left the factory with. All I know is that it's now in there and doing it's job albeit with a bit of a hobo fuel filter bracket (cable ties and jubilees).

Here's what I have learned about the expansion tank

3.4s have a short tank with a fuel filter bracket on the side. Only the C4s use this bracket. C2 the filter is under the car where the axle runs on the C4.

The later 3.6 style tank is longer with a triangle bracket on the side that attaches fuel lines. This is due to the 3.6s having a fuel filter in the tank.

Other differences are the position of the level sensor (side on the 3.6 tank and bottom on 3.4). The return pipe position (roughly 45° difference).

I have no way of knowing what my car left the factory with. I suspect it was the old style tank. Possibly one of the last ones left on the shelf. If this was the case then it seems you can replace your leaking £450 3.4 tank with an £80 3.6 tank.

Just a quick bump to say thanks for this post. I've noticed my expansion tank is slightly weeping and was trying to get some definitive info on the differences between the expansion tanks. Will now go with the cheaper 3.6 instead of the rather pricey 3.4. As I've got a C2 it should be even better as I shouldn't have any issues with the fuel filter.

I'll make a new post with pics while I'm doing the job to clear this up for anyone else in a similar situation.
 

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