F451

Hey guys,

I finally had a chance to find the coolant leak on my '88 S4. Turns out it is the imfamous passenger side end tank. I'll be ordering the end tanks and the gaskets, but I'm wondering what else I should replace while I'm at it.

My list so far:
End tanks (both sides) & gaskets
rad hoses - upper and lower

While I'm at it:
rad expansion tank cap
heater valve & hose (hoses?)

Anything I'm missing?

Thanks,

Ed

Roger

I don't think you should replace the tank on the driver's side. Breaking the tabs on the radiator is the number 1 concern when performing this project. Replacing both will only increase your risk by 100%. I don't recall ever hearing of an instance where the driver's side has failed.

While you have the radiator out, you'll definately want to clean the space between it and the condenser. I assume that flushing the cooling system is also on the list. If so, you may want to take a look at the thermostat and the seal behind it (metal coated with rubber).

Good luck on the project...

Roger
87s4

F451

Thanks for the tips.

I won't be doing the tank replacement myself, I'll be bringing it to a shop that has experience with these types of Behr radiators.

And I just assumed it would be a good idea to replace both tanks, but if the drivers side is not prone to failing, perhaps I'll skip it.

And yeah, I'll be flushing the system.

Keep the tips coming.

Mrmerlin

I would only replace the pass tank, no need to mess with perfection and i hope that they will heat the tabs (anneal)before bending them. and do the same before reassembly. Open both block drains replace the short hose to head and heater control valve, a new cap and a new coolant tankl if your tank is very yellow, it is only a matter of time till it cracks I use Dexcool this is good for 5 years the orange stuff Get the correct side tank find out if you have an internal cooler if you do then you will need the 2 O ring seals. If you dont have a coolin the passenger side tank make sure the parts you order has the block off plates in it , otherwise you will have 2 holes in your end tank since you have a 5 speed and do as Bill said about the Thermostae and the inner thermo seal

Bill Ball

If the thermostat is old, might as well refresh it. I did mine at about 100k miles. There is a seat that needs to be replaced along with the T-stat and it's o-ring seal. Don't just "perhaps" skip the driver side tank. Definitely skip it. That is the cooler side of ther radiator and very rarely fails. I've replaced the passenger sidetank on my car twice. The driver side is original at 182k miles.

marton

might as well put in new water hoses if they are original

Marton

F451

More good advice. Thanks guys!

dr bob

+1

Replace ALL the water hoses if they are over five years old. Relatively cheap insurance IMHO. After all, you won't be working on that system again for a few years, right?

docmirror

May I sell you an unused, NIB end tank from my stock? It's just collecting dust in my garage, and would like to see it used. Pls PM me, reasonable price plus a bit of shipping from TX.

F451

Sent you a PM Doc. Thanks.