Ok so I just got a new thermostat a 195degree I also ordered a new lower radiator hose cause I noticed mine had a hole in it plugged by the old bolt washer trick I'm going to put a new water pump on it and I got a 3 inch fan spacer to put the fan closer to the radiator


I drove the car to lunch today it stayed in the sweet spot on the temp gauge but when I came back out to start it after 15 minutes it cranked and cranked but didn't want to fire until I held my foot in it could timing be a cause for both of those issues I'm used to chevy 350 and 327 and I know timing can make it crank for a good while before it fires

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Old but hopefully a goodie

Read this multi-part article. For that matter, get and read the three books at this thread as soon as you can, too.

Note Simple Green is not an effective cooling system flushing agent. It's a detergent, which won't do a thing about built-up corrosion or silt.

Other possible causes of overheating at speed: a cooling fan installed wrong way around (backwards)...a restriction in the exhaust system.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Git er done.

Btw i have the same issue when i drive my car and park it, if i go to the store and shop for a while, when i come back, i need to hold my foot 1/2 on the throttle for it to start.. Otherwise i can crank all day..

The fuel line is rubber with a 2000degrees heat shield sock on top and routed over the rockercover so it couldn't be fuel boiling.

If i turn it off for 5 minutes and turn it back on, i literally flick the key for 0,5-1 seconds and it starts up like nothing.. But if i let it sit for 15 minutes, i need to push the gas pedal half way to start it.


I'm not sure if this is a standard feature on the slant sixes or some fuel related issue?


My heat is always at 1/4 on the gauge when i drive.
I suspect my gauge is broken..


Does your radiator smoke when you overheat?

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That's exactly what it is: fuel boiling. In the carburetor, not in the fuel line. Time to install a thick, insulating carb base gasket and a large heat shield plate below the carburetor.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

My radiator smokes and boils over

So what would I use to clean the system out

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Old but hopefully a goodie

Other possible causes of overheating at speed: a cooling fan installed wrong way around (backwards)...a restriction in the exhaust system.[/quote]



Would it hurt if I cut the exhaust system at the front of the muffler and just ran straight pipe I'm not worried about noise I just want to drive the things more than 10 miles

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Old but hopefully a goodie

.....if you had a plugged exhaust it would help.....

In any other situation ,,,,,you are making it harder for yourself.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

Is it going to hurt anything like valves or just sound loud and nasty

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Old but hopefully a goodie

You for real? Boy howdy, tellya what: good luck not killing yourself wiith carbon monoxide poisoning, or at least not taking anyone else with you when it happens. I hope your corner of SC is remote enough that nobody else actually shares roadspace with the remains of your car. :shrug:

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I will re route the exhaust just don't want to hurt anything

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Old but hopefully a goodie

Make no assumptions, or plans until the new water pump is installed, and you get the block flushed with real radiator flush. Don't get ahead of yourself here. Also, as WJAJR suggested, it woukd be nice to know the real temp here. If the block is clean, the water pump is good, belts sre not slipping, the radiator is new, the fan is working, the cap is good, and the thermostat is working and installed right it should not overheat.

Check the timimg too. My guess is this is not the likely culprit. Plugged exhaust is even further down the list.

Sam

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The OP reported that he only has overheating issues at highway speeds and not stopped or at low speeds. There should be enough airflow through the rad from the forward motion of the vehicle to keep the engine from overheating.

IIRC, many members here have even removed their fans to improve fuel economy because they do very little low-speed driving.

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1965 Plymouth Barracuda,
225 engine, Quadrajet, HEI, Dutra Duals, 904 Torqueflite, 2.76:1 axle, Addco front bar
Rods & Relics - Fort Erie, ON / Collector Car Tech

Ok new water pump on as well as another new 195degree thermastat I checked timing and it is at 9 initial I'm in the process of flushing the system I installed a new 2 inch fan spacer so my fan is now about an inch off the radiator it's still the stock 4 blade

So my question now is if it still over heats at highway speeds after the flushing what would you suggest doing

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Old but hopefully a goodie

Having read up on Simple Green, it appears that it contains some citric acid, which will remove rust and scale. You might have better results by flushing with Gunk Super Radiator Flush, PN C2124C. I'll be flushing my engine this fall with citric acid that I get from the local DIY wine shop.

Instead of replacing parts, I would check whether the old parts are working properly first. Putting the thermostat in a pot of hot water with a thermometer is very easy to do.

Have you read any of the Cooling System link I referenced earlier?

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1965 Plymouth Barracuda,
225 engine, Quadrajet, HEI, Dutra Duals, 904 Torqueflite, 2.76:1 axle, Addco front bar
Rods & Relics - Fort Erie, ON / Collector Car Tech

I have cooling system cleaner in it and have driven it the last couple days with no problem still haven't taken the freeway

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Old but hopefully a goodie