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Gromit · 02-04-2018, 08:11 PM

I did notice the 850 RPM idle speed you mentioned sounded about 200 RPMs high but since some people like what I would consider a high idle so I didn't want to judge.. I prefer a putta-put-put - maximum 650 RPM or as low as I can get it to run smoothly in that neighborhood. You definitely don't want your centrifugal advance coming in at whatever idle you wanna use.

Hey I may have been wrong about your initial timing being the cause of your overheating but just maybe I was on the right track with my second choice of the heat possibly coming from your TH350. If so it is too bad I wasn't smart enough to link your high idle with the trans fluid shearing forces maybe creating too much heat in the fluid. Maybe a sniff test of your fluid will help to tell the tale. Luckily you can drive it now just put it in neutral at the stoplights.

02-04-2018, 08:11 PM	#100
Gromit Registered User Join Date: Jul 2015 Location: Central Coast, CA Posts: 500	Re: 71 350 running hot coolant backup up problem I did notice the 850 RPM idle speed you mentioned sounded about 200 RPMs high but since some people like what I would consider a high idle so I didn't want to judge.. I prefer a putta-put-put - maximum 650 RPM or as low as I can get it to run smoothly in that neighborhood. You definitely don't want your centrifugal advance coming in at whatever idle you wanna use. Hey I may have been wrong about your initial timing being the cause of your overheating but just maybe I was on the right track with my second choice of the heat possibly coming from your TH350. If so it is too bad I wasn't smart enough to link your high idle with the trans fluid shearing forces maybe creating too much heat in the fluid. Maybe a sniff test of your fluid will help to tell the tale. Luckily you can drive it now just put it in neutral at the stoplights.