Hard Starting Hot

[Rich72C10]

Ran the truck up again for 10 minutes in the garage. This time around after ~15 minutes of being shut off the bottom of Carb bowl got to the same ~125 but the top of the bowl got to 120. Carb Base plate to Manifold still ~135.

Now I did this since after my 1st run I started her up at the end, zero problems. After my 2nd run where the whole bowl was at least 120 I tried again, started right up.

So either I need to drive around normally and not just garage idle but I would think heat is heat (by idling or driving). I also have a ambient temperature of 72 outside but that is not the temp in my garage now after the truck running.

Last bit could be that the STA-BIL 360 has started to help? I filled up and put my measured amount for my tank on Tuesday afternoon. I only driven about 10 miles before my garage test a bit ago (I didn't drive her at all yesterday).

Edit Update after a short ride / keeping hood closed
After about 12 minutes bowl reached 135 throughout the height of it and 150 at base plate. Started a wee bit harder this time but perhaps 1/2 crank more then when cold. Thinking the STA-BIL 360 must be helping.

[Carl Spangler]

Originally Posted by Rich72C10

Ran the truck up again for 10 minutes in the garage. This time around after ~15 minutes of being shut off the bottom of Carb bowl got to the same ~125 but the top of the bowl got to 120. Carb Base plate to Manifold still ~135.

Now I did this since after my 1st run I started her up at the end, zero problems. After my 2nd run where the whole bowl was at least 120 I tried again, started right up.

So either I need to drive around normally and not just garage idle but I would think heat is heat (by idling or driving). I also have a ambient temperature of 72 outside but that is not the temp in my garage now after the truck running.

Last bit could be that the STA-BIL 360 has started to help? I filled up and put my measured amount for my tank on Tuesday afternoon. I only driven about 10 miles before my garage test a bit ago (I didn't drive her at all yesterday).

Edit Update after a short ride / keeping hood closed
After about 12 minutes bowl reached 135 throughout the height of it and 150 at base plate. Started a wee bit harder this time but perhaps 1/2 crank more then when cold. Thinking the STA-BIL 360 must be helping.

FWIW, I found that 125 (ish) degrees at the bowl is the point where I start noticing hot start issue. At 135+ I can hear percolation which leads to heavy fuel saturation and bad ju-ju. There is a whole science about fuel vapor pressure and additives. It would be great if someone would contact STA-BIL and get their feedback about their products and vapor pressure.