Coolant Expansion Reservoir

[dcboxster]

Gents,

My '99 996 C2 Cab's coolant expansion tank is leaking. It is leaking from the underside around where the coolant level indicator sensor is installed. I have purchased a new sensor, but it doesn't come with a seal. I can only assume the seal is inside the tank. Is this right?

If so, I guess I might have to order a new expansion tank, but would like some help before ordering, as my 2 local OPC's here in the UK don't seem to know!

I think the latest revised expansion tank for my car is part no. 996-106-147-56

Thank you in anticipation of a response.

Dave :rolleyes:

[Loren]

You are correct there is no seal on the level switch.

That is the correct (current) part number for an RoW MY99.

[dcboxster]

You are correct there is no seal on the level switch.

That is the correct (current) part number for an RoW MY99.

Thanks, Loren.

Does that mean that the seal for the level switch is integrated into the coolant reservoir?

[Loren]

I am not sure that plastic to plastic needs any seal -- and the parts list does not show one either.

[slbates]

Gents,

My '99 996 C2 Cab's coolant expansion tank is leaking. It is leaking from the underside around where the coolant level indicator sensor is installed. I have purchased a new sensor, but it doesn't come with a seal. I can only assume the seal is inside the tank. Is this right?

If so, I guess I might have to order a new expansion tank, but would like some help before ordering, as my 2 local OPC's here in the UK don't seem to know!

I think the latest revised expansion tank for my car is part no. 996-106-147-56

Thank you in anticipation of a response.

Dave :rolleyes:

Loren is correct. There is no seal. I pressure checked my tank before installation without the sensor even installed and it held pressure. It is a PITA job and I did not want to install a faulty tank. The sensor is a dry sensor and does not come in contact with any coolant. If you look closely in the tank cavity that holds the sensor you will see that it is completely sealed.

Edited July 21, 2007 by slbates

[my996]

I didn't think about pressure testing it before install. I have the tank inserted but not completely fastened in yet. Can it be pressure tested in place or should I take it out and do that first? Also - how do you pressure test it? I have an air compressor if that is needed. Tony

[slbates]

I didn't think about pressure testing it before install. I have the tank inserted but not completely fastened in yet. Can it be pressure tested in place or should I take it out and do that first? Also - how do you pressure test it? I have an air compressor if that is needed. Tony

I capped off the hose locations with vaccum caps and hose clamps. I used a universal rubber cap with a valve in the top. I have had it for quite a while, but I think I may have bought it from a local NAPA dealer. I had to use a clamp on it as well to get it to seal. I put around 15-20 psi IIRC and left it overnight. I have a guage that reads from 0-40 psi on a 2 inch dial. Zero pressure loss overnight. The tank and cap was new, but I wasn't taking any chances. It took me quite a while to get the old tank out. I cut off a piece of the tank that seems to have no logical use but to make the tank difficult to get back in place. Went back in place in no time. It looks like the piece may have been there to hold a circular hose or something??

[Loren]

On both C4, C4S and MY02 and newer the fuel filter attaches to that piece.

[dcboxster]

Gents,

My '99 996 C2 Cab's coolant expansion tank is leaking. It is leaking from the underside around where the coolant level indicator sensor is installed. I have purchased a new sensor, but it doesn't come with a seal. I can only assume the seal is inside the tank. Is this right?

If so, I guess I might have to order a new expansion tank, but would like some help before ordering, as my 2 local OPC's here in the UK don't seem to know!

I think the latest revised expansion tank for my car is part no. 996-106-147-56

Thank you in anticipation of a response.

Dave :rolleyes:

Loren is correct. There is no seal. I pressure checked my tank before installation without the sensor even installed and it held pressure. It is a PITA job and I did not want to install a faulty tank. The sensor is a dry sensor and does not come in contact with any coolant. If you look closely in the tank cavity that holds the sensor you will see that it is completely sealed.

This is very helpful; so if the sensor is a dry one, I guess that it must be its housing that's leaking? In any event, I think I need to order a new tank.

Many thanks for your help. :D

[my996]

I capped off the hose locations with vaccum caps and hose clamps. I used a universal rubber cap with a valve in the top. I have had it for quite a while, but I think I may have bought it from a local NAPA dealer. I had to use a clamp on it as well to get it to seal. I put around 15-20 psi IIRC and left it overnight. I have a guage that reads from 0-40 psi on a 2 inch dial. Zero pressure loss overnight.

Could you post pics of vacuum caps, a universal rubber cap with a value in the top, and the clamp used to seal it, and the guage with the 2 inch dial to read 0-40 psi? I'll go out and get all the parts you have and do this right away. Thanks.

Tony

[Chuck Jones]

When I replaced my coolant tank, at the suggestion of another RennTech'er I bought an extra sensor just in case I broke mine taking out the coolant tank. It comes out as a unit that's totally separate from the tank....and it fits into a 3 inch deep receptacle that's sealed off from the tank. There's no direct liquid contact with that sensor, so it can't leak unless the tank is cracked. If anyone needs a new sensor, I have a brand new one still sealed in the plastic wrapper.

[Keithbeats]

Hey there, hopefully some of you are still around! I was reading up on this and am up for the job since my expansion tank is also leaking. I haven't seen anything yet on whether or not these instructions work on a 2001 Turbo. I may have to remove a Turbo hose additionally. But we shall see.