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mosel70 · 06-19-2017, 01:54 AM

Great replies, thanks!! My dual fans have a total of 2600 CFM. I put Purple Ice in today and also checked idle mixture screws. No vacuum leaks. Still overheats.
The rpm increased when the idle mixture screws were all the way in, but as I screwed them out one turn the rpm dropped a bit but after that virtually no rpm change. Odd, I don't know what to do about that. Whether 2 turns out, or 3, or 4, or 5, it still overheats when at idle (~800 rpm). I noticed driving home yesterday that the temp needle initially stayed under mid range while driving in town and only increased each time I came to a red light. But it wouldn't go back down when driving ~45 in traffic.

I think my last two theories are timing is way off as many of you suggested or TH400 trans torque converter is going bad. I'll have a shop in town check my total timing first. Need to get this overheat thing buried. It's gonna be 115 degrees out this week in Vegas! Many thanks for the great tips!

06-19-2017, 01:54 AM	#21
mosel70 Registered User Join Date: Jul 2016 Location: Las Vegas, NV Posts: 116	Re: Mishimoto Electric Fans in Your 67-72 C10? Great replies, thanks!! My dual fans have a total of 2600 CFM. I put Purple Ice in today and also checked idle mixture screws. No vacuum leaks. Still overheats. The rpm increased when the idle mixture screws were all the way in, but as I screwed them out one turn the rpm dropped a bit but after that virtually no rpm change. Odd, I don't know what to do about that. Whether 2 turns out, or 3, or 4, or 5, it still overheats when at idle (~800 rpm). I noticed driving home yesterday that the temp needle initially stayed under mid range while driving in town and only increased each time I came to a red light. But it wouldn't go back down when driving ~45 in traffic. I think my last two theories are timing is way off as many of you suggested or TH400 trans torque converter is going bad. I'll have a shop in town check my total timing first. Need to get this overheat thing buried. It's gonna be 115 degrees out this week in Vegas! Many thanks for the great tips!