And, THIS is why I do all my own work - I don't let "mechanics" touch my cars. What an idiot. *sigh* But no, AutoZone won't sell Wahler or Behr t-stats. You'll need to buy one from the dealer, an internet MB parts vendor, or a local European parts supplier. Bummer, dude.

Anyway - I seriously doubt this is the cause of your 19mpg. My first thought is also an intermittent odometer. That's tough to spot unless you're watching it all the time, or unless you can go on a long trip and compare to the interstate mile markers over several hundred miles. 19mpg is too low for an SDL. Replace the air filter and both fuel filters if they are not recent. Jack up the car and spin the wheels by hand to check for brake drag... front wheels should spin easily and keep rotating for a few turns. Also check for any fuel leaks. You should be getting at least 22-24mpg or so around town, and on the freeway, at least 24-28mpg. I assume power production is normal? 0-60 time is good at around 13 seconds? If not, you've got other problems...

Be careful with anti-seize... do NOT use a torque wrench, and normal torque specs, on fasteners with anti-seize applied. Otherwise you'll end up learning about Heli-coils and Timeserts. Anti-seize is great stuff when used correctly though. You don't need it everywhere. IR thermometers don't read properly on shiny surfaces such as aluminum (they read lower than actual), so be careful if you're using one of those.

BTW - don't forget to update your "low temp" thread with the holed t-stat photos.

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Check out my website photos, documents, and movies!

And what is this anti-seize? Is that a brand name? Can I buy it at Walmart?

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It's not the years, it's the mileage.

Pretty much any auto parts house will have it. Not sure about Wally World.

Permatex, CRC and others make it. Ask for it at the parts store and they will point you in the right direction. That is an important step that often gets skipped when putting steel parts into aluminum components.

Good job on the coolant! That is what I used. CarQuest carries it down here. Be sure you get all that green crap out. I just replaced my radiator this week and did the same. It was a little time consuming doing the flush, then flushing with fresh water, back flushing everything and un-hooking and re-hooking hoses. I also flushed with the thermostat out so it would not take as long (waiting for it to open). But, I think it was worth it.

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AJ

1985 300D (SOLD)

Do those GPS devices track your mileage as well? I'm a pretty ok navigator and didn't really NEED a GPS...BUT Tracking accurate mileage with a navigation system sounds cool. I never really looked into it.

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It's not the years, it's the mileage.

ON another note, I had my brakes done prior to this whole thermostat meltdown. And I was getting the right MPG during the last days of May and the first of June. After I received my car from the mechanic (After thermostat housing bolt dilemma), I still clocked 23 MPG after filling up. Then on June 25, I clocked 18.80.

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It's not the years, it's the mileage.

After you replace the t-stat, make sure none of the brakes are dragging, as I mentioned earlier... it's suspicious that this started soon after the brake job.

So I'm on my way to checking the brakes...

BUT! No boost? You mean to say that if I don't get a turbo boost, my MPG suffers? I'll check out the vacuum lines and report back...

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It's not the years, it's the mileage.

Check out these videos and tell me what you guys think

http://www.youtube.com/watch?v=djvjj8tRDhE

http://www.youtube.com/watch?v=X2OmksyJwys

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It's not the years, it's the mileage.

I could be wrong, but I think a little bit of brake pad noise is acceptable. The wheels are heavy and won't spin very much in general. Especially if you just replaced the brakes..the pads might take a few days to wear in. The rotation seems ok to me, but I'll let someone with more experience have their say over mine!

As for boost, your mpg shouldn't suffer too much. I went without it for a few months and my mpg was basically the same that it is now. However, if you want to go fast, you might use more pedal for a longer period of time since your power will be down, and this could theoretically reduce mileage. Having the boost will also increase the fuel the engine gets, but you'll get more power so you won't have to use as much pedal.

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Dan
2005 E320 CDI - 246k
1987 300SDL TD05-16g, Herlevi pump, Elbe manifold, 2.47 LSD - 213k
Past: 1987 300D - 264k

You mentioned that you did some modifications to your clutch fan and fan. If you used the wrong fan or clutch, you could be over cooling your radiator. If the fan is always engaged the engine has to work harder to supply power to the fan. If the engine is working harder, it's consuming more fuel. Dave.

Looks pretty normal... there's a bit more drag than optimal, but nothing to cause a drop to 19mpg. The noise is nothing to worry about, probably just the new pads haven't fully set in yet. If you had any serious drag, the wheel wouldn't spin with your finger. Don't forget to check the passenger side too, btw...

Oh yeah - you ever check the 0-60 time with a stopwatch?

Greetings fellow MB lovers! I bring to you an update on what I've done so far.

-I've removed what's on the left of the vacuum pump
-Put in 80C Dealer thermostat
-Checked and reaffirmed for brake drag (seen in the videos)
-MOST RECENT (As of July 3 2009 at 0700) done a 0-60 in what I think is 13s. It's weird because I tweaked my ALDA and yet it's still 13s....hmmmm

Check out my youtube video of my 0-60 time and tell me what you think!

http://www.youtube.com/watch?v=D8C77oO_DpE

I believe I'm gaining MPG back. At the half mark, it's about 20 - 21. Better than 18.80...

A question! You know that thing on top of the overboost protection? the one that's connected to the ALDA and the intake manifold? Is that an adjustment to add more boost?

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It's not the years, it's the mileage.

The 0-60 time seems normal - power output should be ok.



20-21 is still pretty bad.



Not sure what thing you're referring to, but if it's a little box with 3 hose fittings and 2 hoses connected, it's the overboost protection solenoid. It kills the boost signal to the ALDA when boost pressure is too high. It's not an adjustmen to add more boost. Adding more boost does not increase power, it just overheats the intake air. You need more fuel to make more power.

pull the wheel and see if the rotor is grooved, otherwise, it's perfectly normal to have that drag. BTW, all thermostadts are about the same. Don't knock yourself out trying to find a behr or whatever. Delco, Ford(Fomoco) , napa, etc, will do the same job if it's the correct diameter and got the same opening specs.
This is a great source of information on this site. Enjoy it and your car.