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YOUR RESEARCHMY99 996 Cab Water Pump and Thermostat
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Fill back most of the coolant, and i only had
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It filled back most of the coolant, and I only had to top off once after the first drive.
Leading evidence: 'Fill back most of the coolant, and i only had' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean 5-gal paint buckets)' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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I used a basic UVIEW-airlift on the 996, CLK430 and even my wife Honda CRV, worked great every time.
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Suggestion
I plan to measure what coolant comes out to judge how much to put back in (clean 5-gal paint buckets).
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Suggestion
And make sure you measure how much you're filling back in.
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Suggestion
This supposedly helps bleed out air on initial fill of coolant when t-stat is closed/cold.
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Suggestion
On the CLK430 I did a 6 drain/refill cycles since I want to make sure to remove all the old (20+ yr old) yellow G-05 coolant in there and replaced it with the new MB recommended blue G-48 coolant.
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I
plan to flush and replace the coolant. Got to thinking, I should
probably do the water pump and thermostat while I have it drained. As far as I know, the pump and thermos
tat has never been replaced. I am looking at the Whaler 160f thermostat and the Pierburg water pump w/composite imp
e
ller. Ar
e these decent options?
Those are the exact ones I went with last year. Very happy with them. Actually can tell a temperature difference on the gauge while cruising with the low temp stat.
FCP Euro has a good video on replacing both. I might DIY it the next time my car is due. Right now, I'm trying to decide on whether I should get Race Ramps or a Quick Jack system to lift the car.
It wasn�t bad. Took a couple of hours by myself over a weekend in the garage. I didn�t have quickjacks back then, so did the job on 4 jackstands.
I pretty much just followed FCPEuro�s video. Some of the bolts are a little tough to get to. Swivel joints definitely helped. Take your time to clean them the block surfaces before putting new gasket on.
I drained out a little over 3 gallons of coolant during the job. Would definitely recommend using a vacuum filler to refill the coolant if you got an air compressor. Since this is a once in a blue moon job, I just bought the cheapest vacuum coolant filler on Amazon. The quality matched the price, but it got the job done just fine. It filled back most of the coolant, and I only had to top off once after the first drive.
100% what he says about the vacuum fill. You won't use it just once. It's really the only way to fill all the ridiculous number of hoses. I got mine on sale at Pelican and use it at least once a year.
Couple notes as I did this job as my first DIY. It's worth also replacing a couple of pipes, hard and soft, while you're in there. They are cheap - just note the 1999s may have a different pipe that is no longer matching of the downpipe from the reservoir. Read this thread if you want to update some of the pipes (
https://rennlist.com/forums/996-foru...esn-t-fit.html
)
The Porsche brand pump isn't much more, and for a part that is so essential to your engine, I recommend the extra 50 bucks.
https://www.gaudinporscheparts.com/o...mp-99610601157
You'll need to buy the gasket separately. I got the low temp thermo from LN Engineering. Again its a bit more expensive, but not much. You'll re-use the hosing. Here's the parts I order:
Parts and price when I bought in May 2023
996-106-011-57 Water Pump $284.46 1 $284.46
996-106-340-54 Water Pump Gasket $13.20 1 $13.20
996-106-243-54 Tube $71.16 1 $71.16
996-106-850-05 Engine Coolant Hose $46.15 1 $46.15
900-378-177-01 Hexagon Head Bolt $2.01 2 $4.02
900-378-013-01 Sensor Bolt $0.63 5 $3.15
000-043-305-75 Antifreeze/Coolant - 1 Gallon $30.20 2 $60.40
I don't remember what the bolts were for. I may have just needed them for some reason.
I followed a few different videos and all in all it wasnt' too bad. I just made a huge mess on the garage floor when vacumming out all the coolant. Make sure your buckets are nicely close to your engine. Also make sure you also disconnect the heat core pipe and push coolant out of there too. Also recommend flushing a lot of distilled water through before refilling. And make sure you measure how much you're filling back in. I didn't pay attention and I started second guessing myself if I had left a big air pocket in there, or if i had not flushing all the old coolant out.
With the labor I saved I bough a set of Quickjacks, best investment ever.
FYI - my water pump and thermostat was replaced recently and I noticed no difference in fuel economy with the lower temp thermostat (5w/40 Motul). I was trying to figure out if there are any downsides to running the lower temp, and this is the only one I could think of (condensation is not a factor given the vacuum and heat in the crankcase).
I agree I can't figure out what the lower temp really does long term. I live in SoCal and it is HOT in the summer. I drive the car hard and it gets to high temps. Sure the low temp thermo kicks in earlier, but the car is going to max temp regardless either with the thermo opening sooner or later. It's like that fallacy of setting your houses AC temp super lower thinking that the lower you put it, the faster the house will get colder...
Engineer here.
I have the low-temp thermostat and it does not keep the temperature low for long but it does slow the progression. I consider it to be like an insurance policy I bought to protect the engine for a seemingly rare event. Since the engine is made of parts of differing materials and those materials expand at different rates as the engine heats up, by marginally slowing the rate at which the engine coolant heats up, it allows for a more orderly expansion. On the low temp thermostat page at LN Engineering, they say it minimizes "hot spots." This is basically the same thing.
With that Wahler T-stat, I like to drill a small 3/16" pilot hole or air bleeder hole/popit valve/jiggle pin, whatever you want to call it. The LN t-stat has one, as do most quality t-stats.
This supposedly helps bleed out air on initial fill of coolant when t-stat is closed/cold. Also allows some small/more flow even when tstat is closed to help prevent pump cavitation if engine is rev'd when cold/tstat closed....
Don't really need the little rivet in there, but put one in nice and loose if ya want...
jmo
Do you have a link to the Vac Coolant Filler tool on Amazon? Did you clamp any of the hoses, like by thermostat, to reduce amount of coolant going in buckets? I ordered some "Hose Pinch Tools", that lock with a band on handles. I also have some rubber stoppers, one of which fits the thermostat housing as an idea to try. I plan to measure what coolant comes out to judge how much to put back in (clean 5-gal paint buckets).
I'm doing CV joints and rad cleaning in the front for now. The bottom panels must have been off at times, because there are a mess of different plastic push connectors, colors and sizes. Whatever...
Air lift:
Amazon
Amazon
If you're draining the coolant to refrill with new, you don't want to clamp anything off. The Aircompressor will push everything out. You just need to make sure you disconnect the line by the heat exchanger as there is a spot where coolant and sit lower than the air going over it (at least that's how it was explained). Sure enough there was a bunch more coolant in there.
You want it empty, unless you are planning on reusuing old coolant, but not sure why you'd do that. In which case you would just open the drain and let it all flow out. Though, again, not sure why you'd leave coolant in there.
https://a.co/d/5FRbYJ6
That�s the one I used. Like I said before, the quality matches its price, but it got the job done just fine. I did not want to invest in an Airlift for a job I�m only going to do once every couple of years.
I drained the coolant from the engine block first. That took care of the coolant reservoir as well. Some more came out when I popped the thermostat off, but it was fairly easy to catch with a pan. Had minimal spills overall.
I wouldn�t bother clamping the hoses to be honest. You�d want to use this as a chance to change out some of the old coolant anyways, so get out as much as you can.
Doing the job drained about 3.5 gallons of coolant, and the vacuum filler put back about 3 gallons, and I topped it off another 0.5 after the first test drive on the highway with the bleeder valve open, maybe another cup full a month later cause I�m OCD on wanting the coolant level right at MAX. It�s been a few months since then, coolant level has remained right at MAX without any issues.
if you want to get all the coolant out
use
@Ahsai
's method
https://rennlist.com/forums/996-foru...ispreloading=1
vac tool to refill is worth the money and peace of mind.
Same here with the Vac filling tool recommendation, best investment tool for all coolant refill jobs. I used a basic UVIEW-airlift on the 996, CLK430 and even my wife Honda CRV, worked great every time. On the CLK430 I did a 6 drain/refill cycles since I want to make sure to remove all the old (20+ yr old) yellow G-05 coolant in there and replaced it with the new MB recommended blue G-48 coolant. The Vac tool allowed a very quick and easy refill each time without any air in the system, one less thing to worry about... Cheers,
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