Not sure if it's popular on Caymans but on 996/997's the low temperature thermostat sold by LN Engineering is a popular thing to install.

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Yes, leaning toward the 160* stat as well. http://forums.pelicanparts.com/suppo...s/beerchug.gif

I've never seen a metal impeller fail. What fails is the seal or the bearings.

common failure on the VW TDI's when replaced with a plastic impeller. OE is metal.
Plastic ones fail when the glue between the impeller and shaft fail and the shaft freewheels...

However those are on iron block engines... I like the argument since it's an aluminum block; it needs a plastic impeller.

Seems like I saw an account on Rennlist of spmeone’s metal impeller pump taking out some of the block. Considering that it’s common to have the bearings start getting loose and leaking, I wouldn’t want to take the chance with a metal impeller. Go brass or plastic.

Ive done a lot of searching on water cooled forums and found a lot of warnings about the metal impellers. That is all. Warnings but no one actually saw one destroy a motor. So far.
Heading out to get some hose crimpers and E torx sockets. Later today I will order some parts. Not sure what parts but I will order something.

It happens. Go over to Rennlist and check it out on the 928 forum. I think someone actually made a block repair kit for those engines. Usually you are going to run out of water before you kill the face of the block, but not always.

I think you are correct. A bad bearing will let the impeller wobble and hit the block but the seal should give up before the block is hurt. I wanted to get a look at the old pump today but decided to wait until I have parts. If it is together I can at least move it in and out of the garage if needed.

The Porsche pump is good for maybe 35K miles. Some last longer. Tony Callas (Rennsport) and some p-techs recommend 35K as a preventive measure for replacement. Why? It is a small pump in a tight spot designed to pump just enough with out too much power robbing parasitic draw. (Racecar origin)

I would think the metal impellers might cause more seal wear due to same size seal but more weighty impeller. YMMV.

LOTS of threads on RL about this... The OEM plastic impellers get eaten away over time and dislodge and block vital coolant passageways and boom goes your engine. If the bearing fails on the metal type, it will score the block making it useless... Tough choice... If you go plastic, go with the 997 OEM part. Has a more robust plastic impeller.

Ordered pump with a brass impeller. 160* thermostat, an OE belt and gaskets. Just can not see a $250 pump. When I post up 2 years from now about my trashed motor you guys are welcome to beat me down. I promise not to blame Pelican for selling me a crappy pump. :D:D

I’ve done probably 50 of these and haven’t seen one “eaten away.” They break when the impeller contacts block. Usually after a guy has been limping one along, adding coolant every so often instead of getting around to replacing it.

The new updated part is a 997 part number, I don’t think you can get old 996 part though some places may still have inventory.

No way I’d replace factory t-stat with some other brand....

Of the 50 you have done, did any have damage to the block ?

I'm putting this under water cooled, seems fitting
 

-15 C here today with a wind chill factor of -30C (Here they call it "Windshield factor)".

I've worked at this wharf for more than 45 yrs and this is the coldest I've ever been.http://forums.pelicanparts.com/uploa...1514401915.jpg
http://forums.pelicanparts.com/uploa...1514401957.jpg

Probably half of the ones we've done at the shop have had some pieces missing/broken off of the plastic impeller type.

Yellowperil, That looks seriously cold. It was 7* F here this morning.

Just light scuffing. And yes, a few with pieces missing but not eaten away like dissolving or anything. I have a way to get pieces out but usually not needed, though I make sure to let customer know that it could be an issue. They usually look pretty good, just leaking.

Thanks. I am dieing to see whats is under my pump and if it is original with 81000 miles on it. The belt is OE but it looks too new to be factory. I bought a new OE belt to put on. I also bought the 160* thermostat but I am not sure I will use it. Its 18*F here and parts should be here Saturday, so no point in heating the garage before then.

I just installed a Pierburg replacement, supposed to be the OEM
Came with composite impeller.
looks just like the pump that came out.

(which as it turns out was leaking on the gasket, the bearing and impeller was still just fine)
Installed the cooler 72C thermostat as well

Pierburg on top A+
That's what I'de get if it's available. Payed 177€ for mine.


A skf, geba, laso supposed to be good as well
B then it's meyle, metzger, febi etc
C the obivous no name chicom made crapola

Or obviously you can order Porsche original teile
Just make sure to order some lube up front

http://weknowmemes.com/wp-content/up...ing-in-dry.jpg