Hey Friends! I searched the posts and too my surprise didn't find the answer to my question.

I recently replaced the thermostat on my 82 300SD. The coolant temp runs about 85 C once completely warmed up. I live in Massachusetts where the outside temp is 30-50F right now. The "problem" is that it seems to take a full ten (10!) minutes for the engine to warm up all the way. It climbs slow and steady up to 85. I do mostly about town driving so most of the time the car isn't completely warm. It definitely performs with more pep and better shifting once up to 85. Should I have to wait so long? Seems like my wife's Honda is up to temp within two blocks. What do you think?

__________________
Orion Parrott

300SD 1982 202k
300TD 1987 275k
Suburban 1987 6.2D 4x4 156k
200D 1967 gone but not forgotten
380SE 1985 gone

10 minutes to warm up to normal operating temperature seems normal to me for a 617 engine.

__________________
Nate

1995 E420
1992 BMW 525i
1984 300D Turbo sold
1993 Volvo 244 sold
1995 Volvo 944T R.I.P!


"The details are not details. They make the product."
-Charles Eames

www.cbs.nu

The 617 seems to take forever to warm up.

The 603 warms in 1/2 the time. Probably makes it to 80° C. in seven minutes or so, driven very easily.

I noticed that if I let mine sit in the driveway and idle it will never get to proper temp. Only after driving will it climb to normal operating temp.

__________________
'85 300SD (formerly california emissions)
'08 Chevy Tahoe
'93 Ducati 900 SS
'79 Kawasaki KZ 650
'86 Kawasaki KX 250
'88 Kawasaki KDX200
'71 Hodaka Ace 100
'72 Triumph T100R

The Honda also does not have a real coolant temp gauge. It is programmed to simply stay in the middle regardless of temp unless it gets way too hot or way too cold.

Mercedes have a coolant temp gauge that actually displays the correct coolant temp.

__________________
Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record

I wouldn't let it sit and warm up-mine smokes and starts to load up with carbon if allowed to idle excessively-it does warm up quicker than 10 minutes, though-you might want to check the stat suspended in a pan of hot water with a thermometer-I've had a few that didn't close all the way and opened early. I also wouldn't put a lot of stock in the factory gauge-after 20+ years, they're usually off a little.

__________________
1982 300DT 190K (Diesel Purge + synthetic oil=smoothness at last!!!)
2004 Ford E-350 6.0 L PSD 227K
2006 Dodge Ram 3500 SRW HO Cummins 4X4 48RE 42K (brute force tow vehicle)
2005 Scion xB wife's rolling pop can
1993 GMC Sierra C3500 6.2 142K

Actually the engine really isn't "warm" until the oil pressure drops off to 1.5 bar or so.

My SDL takes a bit to warm up, the 606 warms up about twice as fast.

__________________
2020 GMC Sierra Denali
2007 Tiara 3200

If you have the heater cranked it will take even longer to heat up. If you want it to heat faster it needs more load. I f i leave mine idling i turn on the lights and the rear defrost to give it some load and it heats a little faster. My TDI beetle has a harder time heating up than my 87td. Remeber diesels are heat engines and they use there heat very effiecently.

__________________
82 Rabbit diesel (first d), 84 Jetta turbo d (300k when sold), 83 240d (305k when sold), 84 F250 6.9d w/Banks turbo(parts truck), 86 F250 6 cyl.gasser(waiting for 6.9d), 84 300d ( 347k Sold 8/04), Y2k New Bettle TDI (185k miles), 95 740IL (wifes), 87 300TD (206k Sold 7/05), 05 Passat TDI Wagon

Thanks for all the useful comments! I can stop worrying now. Cheers!

__________________
Orion Parrott

300SD 1982 202k
300TD 1987 275k
Suburban 1987 6.2D 4x4 156k
200D 1967 gone but not forgotten
380SE 1985 gone

I usually let it warmup until I see the needle start to move off 40 then drive conservatively until it reaches operating temperature.
Then I get on it!

Danny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination

Interesting, mine usually reaches 80 after a few miles and doesn't go any higher under any circumstance.

__________________
Adam Lumsden
(83) 300D
Vice-President of the MBCA International Stars Section

Mine takes about 2 miles worth of conservative driving or about 15 minutes of idling to reach its normal operating temperature, my dads takes about twice as long and runs cooler in general, probably a t-stat issue but it still gets up to 80-81C so we're not concerned for now.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 102k - mine - (OC-104,600)
'17 Metris(VITO!) - 26k - wifes (OC-25k)
'09 Sprinter 3500 Winnebago View - 57k (OC - 63k)
'13 ML350 Bluetec - 73k - dad's (OC-75k)
'01 SL500 - 92k(km) - dad's (OC-94,000km)
'16 E400 4matic Sedan - 122k - Brothers (OC-125k)