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Coolant change = higher temp?

1645 Views 16 Replies 6 Participants Last post by  300se126
OK, feeling a little bit like an idiot here. Changed the two radiator hoses and the coolant last week and now have higher temp at idle and a slower cool down time while cruising. Used Pentosin coolant right at 50/50 but have noticed that while cruising temp is normal, right at 80c, at a stop the temp climbs rather quickly to right at 100 c and then when I take off it goes slowly back to 80c. Fans come on fine but I want to know what I did wrong with the coolant change to cause this because before old knucklehead (me) got his mitts on it it was fine, usually rock steady at 80c. Can air get trapped in this system and cause this? I let it run without the rad cap long enough after the thermostat opened but I wonder now. Any ideas? With hot Sacramento summer temps coming soon don't want to let the old girl get hot.
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I looked up the procedures on ALLdata and saw a note that no bleeding procedure applies to the 103 enigne but I know there is a bleeder on top of the thermostat housing. Gonna try again tonight to purge any air out through the reservior with the system open. We'll see what happens.
Cannot find a locator for the bleeders, anyone have pics of them?
I thought that might be them, two 13mm heads with copper washers under them? Seems kind of strange to have 2 so close to each other. Anyway, I ran it last night with the cap off until I had a hot return hose from the top of the radiator, did not see any air or bubbles so maybe it's OK now. We'll see. Thanks Jonathan
300se126- the Pentosin I got is blue. You got it in red? What, do they offer designer colors???LOL BTW I like your 250,000 km badge, I have one on mine too.
Found and used the cylinder head coolant bleeders with little success in decreasing the operating temp. Strange thing is last night while I was trying to figure this out, I had the overflow cap off and the engine idling and the temp was over 100c and the fans even came on with the cap off. I coudl feel the hot coolant flowing through the return hose to the reservoir so I know the thermostat is opening. Now I am questioning if the coolant/water mix is not correct and causing the increased temp. I mixed it right at 50/50 but now I wonder if I need to increase the water amout.hmmm? Anyone care to offer any opinions?
It was the thermostat all along. Just a coincidence that it went when I did the hoses. Replaced and all is well.
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