Fixing one thing leads to another...

Gaz64 · #1 (**permalink**) 02-12-2018, 12:35 AM

The trouble with late model Holleys now is they all run the more efficient umbrella inlet check valve in the pump cavity, but they all don't have a pump bleed back to the bowl, typically. 013, so when the pump chamber gets hot, it dribbles out the pump nozzle, flooding the engine.

You can drill a .013 hole outside the umbrella so the pump can bleed back.

Some guys machine a groove in the bottom of the bowl near the edge of where the umbrella seats.

Early bowls with their hung inlet check ball rarely suffer from this condition.

Gary

Ron61 · #2 (**permalink**) 02-12-2018, 04:33 AM

Just for what it is worth but both my small block and big block run the oil temps at around 240/250 and the water at 210/220. They were designed to run that way and if they don't get up to that temperature they don't run as well.

Ron

bingo2 · #3 (**permalink**) 02-12-2018, 07:27 AM

Just throwing this out there. Ford, back in the 60s, began installing 195 degree thermostats in most of their engines. Then began advertising longer oil change intervals and better fuel economy.

DanEC · #4 (**permalink**) 02-14-2018, 06:24 AM

Quote:

Originally Posted by Ron61

Just for what it is worth but both my small block and big block run the oil temps at around 240/250 and the water at 210/220. They were designed to run that way and if they don't get up to that temperature they don't run as well.

Ron

Wow Ron - that seems really warm for oil. I think my GTX can get up around 220 on a hot day wit AC on but that's about it. Did Ford equip the Super Cobra Jet with an oil cooler - I was thinking they did? Of course most of the engines only ran 5 qts oil back then with some running 6 so they did run warm.

tortuga · #5 (**permalink**) 02-12-2018, 07:18 PM

Quote:

Originally Posted by Gaz64

The trouble with late model Holleys now is they all run the more efficient umbrella inlet check valve in the pump cavity, but they all don't have a pump bleed back to the bowl, typically. 013, so when the pump chamber gets hot, it dribbles out the pump nozzle, flooding the engine.

You can drill a .013 hole outside the umbrella so the pump can bleed back.

Some guys machine a groove in the bottom of the bowl near the edge of where the umbrella seats.

Early bowls with their hung inlet check ball rarely suffer from this condition.

Gary

I'm going web hunting for a how to on this!

Thanks!
Steve H

patrickt · #6 (**permalink**) 02-12-2018, 07:45 PM

Quote:

Originally Posted by tortuga

I'm going web hunting for a how to on this!

Thanks!
Steve H

It's a relatively obscure point; I've never had to do it myself. But you can read about it here: https://www.musclecardiy.com/perform...-pump-circuit/ Just skip down to the paragraph that starts with The accelerator pump system needs to counter the following two situations...

Gaz64 · #7 (**permalink**) 02-12-2018, 11:59 PM

Here it is here:

The accelerator pump system needs to counter the following two situations. So as not to discharge fuel through the squirters when the throttle is opened slowly, in some systems there is a controlled bleed from the pump back into the fuel bowl. Older carbs have a check valve located within the pump. When the throttle opening rates exceed a certain amount, the check valve closes and the fuel is redirected solely to the squirters. Also worthy of note is that some aftermarket Holley specialists drill a small bleed-back hole through the pump roof/float bowl floor. This hole needs to be small (about 0.012 inch), but it can be used as a tuning aid for the pump system in much the same way as Weber pump jet float bowl bleed-backs.

Good to see this in black and white,

.

Gary

Andheeezonit · #8 (**permalink**) 02-13-2018, 05:30 AM

I believe you changed to a Shaw Stat correct. If you are running a stat extension and did not take note of your clearance, you may have a flow issue, which I believe I cautioned about. More likely to cause a hot motor than the oil cooler stat. Check this out, you may have to have the ID of your stat extension bored, I know I did.

tortuga · #9 (**permalink**) 02-13-2018, 08:59 PM

Quote:

Originally Posted by Andheeezonit

I believe you changed to a Shaw Stat correct. If you are running a stat extension and did not take note of your clearance, you may have a flow issue, which I believe I cautioned about. More likely to cause a hot motor than the oil cooler stat. Check this out, you may have to have the ID of your stat extension bored, I know I did.

But coolant is just fine, is working better than whatever old crummy thing that was in there...I did have to modify the housing for the Tstat to fit.

What's hot is the oil...it controls rock steady at 215, coolant is also rock steady at 185. Just seems to me like all that hot oil cooks the block a bit after shut down.

I think my big old billet fuel log and collection of fittings was transmitting a lot of heat to the carb...the hoses seem to be much better!

Thanks for your response

Steve H
SPF 1764

Gaz64 · #10 (**permalink**) 02-13-2018, 10:00 PM

Canton claims 215 is to have condensation evaporate out of the oil.

I tend to believe this theory:

https://www.offshoreonly.com/forums/...temp-chart.jpg

And here is a thermostat that can do that:

High-Flow Engine Oil Cooler Thermostat, 185F FSM-185

There are many others out there.

Yours rock solid at 215, shows the thermostat AND cooler are working well, just a bit high for me.