Overheating

[TTM]

Nick, as far as I know Laso are the only maker of 944/928 water pumps, meaning the quality may be rather consistent regardless who it's purchased from.

 

[simkin911]

ORIGINAL: zcacogp Depends upon what you mean by "hideously expensive". Porsche want £466 for a waterpump. Fitting it involves removing all the belts and re-doing that job entirely, so whatever you paid to have the belts changed in the first place will have to be paid again (plus a bit more, as there's a few more parts to replace.) At £70/hr (what my local indie apparently charges) that's all going to work out quite pricey ... which is why I am trying to source a cheaper waterpump and will probably do the work myself. Oli.

Sorry, my "hideously expensive" remark was based on an assumption you'd be buying the pump and getting your hands dirty!

 

[nick_968]

Thom, I thought the same until I read this post: Thanks. I am really hesitating in thinking about reinstalling my original pump... but these supposedly OEM Laso pumps that say they are Made In Germany... must be made in East Germany in an old Trabant car factory. They exhibit issues such as the bevelled hose flange that has a deep depression in it. What caused this? They are working off a faulty casting model where they created a depression in this area (before machining)... and is misproportioned... since that area ends up being lower than the dimensions after machining the flange. So, this does not provide a good initial seal or even surface against the radiator hose. I have received two of these pumps... and they exhibit the exact same flaw in the exact same area. And I have conformed from other sources that this is the way all of these are coming in. Though this can be filled with something like JB Weld... it is ridiculous that these parts are not made right in the first place. Jeez... after the first one was made this way... how could Laso ever make the second and third, etc., this way?? When compared side by side with my factory pump... it is hard to believe that Laso was the original OEM supplier to Porsche. The units are not the same. Even the water passageways are shaped differently. And dimensions of things like the nose of the pump where the right angle fitting (951.106.313.00) sits... is different. I am beginning to wonder what "OEM" means when talking about these parts. These are clearly not the same parts as Porsche put in my car. And... let's face it... no supplier is going to change the design of a part for a car when that car has been discontinued. Manufacturers don't do that... they just keep supplying the same part they always did. I just do not believe that Laso was the supplier to Porsche for these pumps. I believe that they decided to make the pumps for the cars after the fact... they were not the original supplier to Porsche for these 968 pumps. As far as Porsche availability of pumps... the estimate I received the other day was that they are backordered... and showing 12 weeks. I have someone at a dealership investigating this further for me... and will relate the results. It is quite unbelievable that Porsche does not maintain an adequate supply of a part that is known to fail. One could understand a week or two or three in procuring a part... especially for a recent production street car (not a collector car)... but 12 weeks?? Unbelievable...

 

[nick_968]

Not sure how accurate the above info is as it was a couple of years old, but it certainly made me think twice when I read it. Hence my post asking for feedback on the quality of the Laso pump when it arrives.

 

[zcacogp]

ORIGINAL: nick_968 Oil

>Snigger< You're not the first one to make that mistake; I once had a friend in the oil industry, and she said her fingers were incapable of writing 'Oli', they simply HAD to type 'oil'. Hence every eMail she ever sent me was addressed to 'Oil'! I will check the quality carefully. I didn't know that Laso were not OE ... now I'm worried ... [] Paul, it sounds like it's a bit of a classic; change the belts, and the tension of the new belts causes the shaft of the old waterpump to snap. (I know I overtightened the cam belt - the critical one - when I first did the job.) Having said that, I know the pump was at least 80k miles old, so it had done it's time. In fact, it was probably on borrowed time when it snapped (assuming that is what happened - I haven't yet dismantled it for a full diagnosis.) In the light of this, I don't know what recommendation you should make for others. Perhaps a pump every second belt change is a wise precaution; I am aware that if someone was paying for labour in my situation, they would be just about to stump up another £300 or so to have the belts removed, the pump changed and those nearly-new belts replaced. Which looks like a false economy when you could just have paid for the new water pump the first time it was all in pieces ... Oli.

 

[Lowtimer]

Pump change every second belt change is my understanding of the proper regime.

 

[TTM]

Nick, a reason good enough to change a casting is to save costs. Given the number of Laso water pumps now supplied out of the Porsche network and the fact that 944/968 people around me who have run one for several years without seeing a failure I am not sure I understand why the details mentioned above would be any detrimental to the actual performance of the pump. Given that a Laso pump costs about less than half a Porsche-supplied pump it would anyway remain more cost effective for overly-concerned owners to replace it at every belt change while most would seem to agree that a Porsche-supplied pump may reasonably be replaced every other belt change. As for Porsche not being able to supply "quality" parts, we all have to live with the fact they haven't cared less about front-engined cars since they stopped making them. I'm sure this is not only a front-engined Porsche thing anyway, I'm sure there is a myriad of old parts for 911 that now come out with poor quality.

 

[nick_968]

Point taken Thom and I agree with what you say. If you and others have been using them with no problems then I have no issue with them. My only concern was that often when things look poor externally the same quality is carried out internally. Personally I couldnt care less what it looks like as long as it does its job....

 

[nick_968]

Oli....yes I spelt it right this time!! Laso are OE as far as I am aware, just that there can often be differences in OE parts was just raising the point for discussion and a good answer by Thom there, sounds like your pump will be fine.

 

[zcacogp]

Here's hoping ... I'll compare the old and new carefully when it arrives and put some photos up here. The new one is apparently in Bremen at the moment. I took the plunge and bought one from German eBay (about a third of the cost of one from an OPC, and that includes shipping to the UK.) I'll be on tenterhooks until it arrives, that's for sure ... Oli.

 

[xenon]

Keeping the same belts?

 

[zcacogp]

Yes - they are about 1500 miles old, and (unless someone can tell me otherwise) I can't see any reason to change them again. Oli.

 

[xenon]

No I agree - I meant have they been contaminated by coolant spray or anything?

 

[zcacogp]

Ian, No - no contamination. The coolant has all stayed where it belongs and none has leaked. (And anyway, I don't think that coolant is damaging to belts is it? Oil will rot them, yes, but coolant - water and ethylene glycol - shouldn't harm them.) Oli.

 

[xenon]

Agreed - it's just that the coolant with the glycol is slippery and never dries - could make the belt(s) more prone to slipping / jumping (??)

 

[zcacogp]

Interesting, and a good point. Hadn't thought of that. The belts look pretty much identical to when they were fitted last month, but I'll have a close look and make sure that there is no such stuff on them before refitting. Thanks for the tip! Oli.

 

[TTM]

I forgot to say my S2 has done 50k miles so far with a non Porsche-supplied Laso pump, my friend Sly did 36k miles since his first engine rebuild, I'm on 12k miles with the 3.0L turbo engine, none have developed any issue...yet. Of course there is always the bad luck of getting one that will fail but it is also true of the Porsche-supplied pump. I'm not affiliated to Laso by the way

 

[VanhireBoys]

Sorry to hear this Oli....!This same problem happened my old Cavvy SRi .. The waterpum "fan" was disconnected from the pump shaft...! You might come across this when you take the old one out...! My belts were done without the pump in '05.. I am really pushing it at this stage.. Its pump and belts this time. I have to take the car to Galway to get the work done .. I think ill get it on a trailer to be right..... This is a good lesson to us all...!

 

[zcacogp]

I know what I am expecting when I take the old pump out; the impeller dropped off the end of the pump, and flapping around in the pump cavity, being repeatedly kicked about by the end of the (sheared) shaft. I am curious to see whether I am proved correct! (And am hoping that there won't have been any damage done to the sides of the pump cavity. What forms those sides? The outside of the cylinder block, I guess.) It would (in retrospect) have been an ideal opportunity to try out a car modification I have often contemplated - an electrically-driven, thermostatically controlled water pump. A waterpump needs to be geared such that it will pump enough water to cool the engine in the worst case scenario, which must be sitting in traffic on a very hot day. However, given that the waterpump speed is proportional to engine speed, it will therefore be turning much more quickly (and therefore unnecessarily quickly) when giving it some beans. Fitting an electrically-driven pump that pumps at a constant speed would mean less power sapped from the engine. You could also avoid the use of a thermostat in this scenario, as the pump need only turn on when the engine is up to temperature. What sort of power is taken by the standard waterpump at 6000rpm? And what sort of flow rate would you need for a replacement electric pump? Oli.

 

[xenon]

That's how the pumps work on (some) of the BMW "efficient dynamics" engines. Parasitic power drains are electrically driven or coupled. Another good one is a power steering pump - in a conventional system it's turning completely unnecessarily, and quickly, when you're driving on the motorway in a straight line.