Author Topic: Is 220 degrees too hot?  (Read 694 times)

April 05, 2019, 01:48:10 pm


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Is 220 degrees too hot?
« on: April 05, 2019, 01:48:10 pm »
 What is the optimum coolant temp for a 1.9TD?
 180 degrees to what?

 On my samurai conversion, I was getting 215-220 deg after climbing a long, off road 300m climb in second gear. Temps hit 220 at the top of the hill.
 Yep, both fans were running, and the temps did come back down to 190 after a few minutes of idling.

 Assuming my T stat is the common 87 deg. I now have an 82 deg T stat to swap in.

 What is the temp that you don't want to hit? ......risk of overheating, warping the head, etc..

Reply #1April 05, 2019, 08:57:05 pm


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Re: Is 220 degrees too hot?
« Reply #1 on: April 05, 2019, 08:57:05 pm »
I would say it is more of a function of how hot and how long.  The cooler on the oil filter gets its water off the bottom of the radiator so it should be less than what ever you have for a thermostat but not by much.  That of course only applies if the radiator is working as designed.  And that you don't have other items stacked in front of it.  Like aftermarket oil cooler or intercooler. 

If you spike temps occasionally to the 210 mark I doubt you will do damage if you have proper antifreeze coolant to keep boil over from happening.  If you are running simple water then you are risking steam out the coolant reservoir and then less fluid in the future.  Bad choice in my mind to run water unless it is an emergency fix.  With the price of a gallon of unmixed antifreeze at about 10 bucks you can give up a beer and a coffee for the day and save your engine.

My gauges, Mechanical, tell me I run around 90 C or 185 depending on the vehicle I am driving.  I don't have extreme heat here on the Pacific ocean to contend with but rather I fight a cool engine most of the time.  So I run a hotter thermostat rather than a cooler one.
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Reply #2April 06, 2019, 12:25:46 pm


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Re: Is 220 degrees too hot?
« Reply #2 on: April 06, 2019, 12:25:46 pm »
 As a comparison, in my 95 golf, DD, 1.9TD, I run about 85-90C on a warm day, normal commute. A littler cooler on a cold day tho, say.....if it's 5 deg C outside. oem vw rad and vw pink coolant.

 My question is regarding my samurai with aaz. It's got the Acme diesel conversion rad, and vw pink ?G12? coolant. All of the cooling components are brand new, except the T stat.

 Been taking it off road and the temps sure climb as the elevation and long grind up the mountain in second gear continue. On the pavement commute, it sits around 85-90C +/- a little depending on the hills. If it climbs past 90C going up a hill, the temp comes back down quickly when I get up onto the flat, or the downside of the hill.
 I do have the fuel turned up, 1.6TB boost pin, and max boost of 15 psi for the Ko3. Water / meth injection also.
 So yeah, the zuk is heavier than my golf, runs more rpms vs kmh than the golf, and of course the air flow through the rad is not great at only 20 mph [ second gear ].

 I'll consider 220 deg the time to pull over and let the engine cool......until I learn otherwise. Better safe than sorry.

 BTW, 90C = 194F
          85C = 185F
           104C = 219.2F         
« Last Edit: April 06, 2019, 12:28:16 pm by Spokerider »