Driveability issues on my slant.

[RAT ROD AL]

On my A100 van I'm having a stalling problem when the engine is up to running temp @ 190 and get into stop and go traffic the temp slowly gets up to 200 -210 and starts running rough and dies and wouldn't restart . With the air cleaner off , looking down the holley i could see no gas squirting when working the throttle . Had to pour a little gas down the carb to start . ran rough till it cleared up and was on my way again. This has happened a few times . I changed the fuel pump (no help) I then replaced carb with another one I had put a kit in , It runs better but still stalls, like if i run it up to temp and then shut it off for a few minutes and try to restart. With the replacement carb it does restart but runs rough till it clears up. ( as in reving it up till seemingly gets some cooler gas in the carb ????) I have the stock intake and exhaust manifolds on it. The fuel line from the pump to the carb is the stock steel line in place. It also has a new fuel tank and filter. Any ideas or solutions would be helpful, i don't know what else to try. Would be nice to solve this problem before I swap in my new slant. Just seems the carb and fuel is getting to hot cooped up in the engine box.

 

[valiantwagonguy]

sounds like vapor lock. Make sure your fuel lines are not too close to the manifold and you can wrap them in some insulating material.Also, have the radiator boiled out.It is creeping up in temp because there is something blocking the free flow of coolant .That is usually in the radiator and drop the temp to a 180 stat.

 

[RAT ROD AL]

By the way on a new water pump which is better the 6 or 8 blade ? I heard sometimes if you move the coolant too fast it doesn't have time to cool off or cool the engine down, anything to that? And also , a new pump comes with one gasket , does it also need one between the plate and housing?

 

[sireland67]

Check the heat riser on the exhaust manifold and and make sure it is not stuck.

Nice old van, I had one years ago.

 

[Steve 225]

I agree that it sounds like vapor lock, I had a 66 mustang 6cylinder that used to vapor lock all the time, aluminum foil wrapped loosely around the fuel line to act as a heat sink helped some, but didn't stop it completly
This is going to sound crazy but, next time it acts up, put some ice in a shop rag and tie it around the fuel line, near the carb if it stops doing it then it's defiantly vapor lock( once we drove from Fla to Ohio stopping every 50 miles to add ice, I've been trying to forget that adventure for 30 years now, but we got home)
as far as coolant flowing too fast to cool properly, I've been told that's why to always run a thermostat even in summer, it slows down the coolant flow so it cools enough
But all these are things old shade tree mechanics told this old shade tree mechanic, when he was a young man

 

[1963dartgt]

Fuel Line Mod Improves Starting & Driveability - Slant Six Forum

 

[valiantwagonguy]

By the way on a new water pump which is better the 6 or 8 blade ? I heard sometimes if you move the coolant too fast it doesn't have time to cool off or cool the engine down, anything to that? And also , a new pump comes with one gasket , does it also need one between the plate and housing?

I don't think the 6 vs 8 blade pump is an issue with a slant 6.I think your problem with the temps slowly rising in your motor is in the radiator . I have had this problem more than once in my old Valiants and my 71 Chevy C20. It was always the radiator especially in the automatic transmission cars that use it to cool the trany fluid.An oil cooler may help you cool that fluid( if your van is an automatic) before it enters the radiator to be cooled a second time.I'd also flush out the block with a good cooling system cleaner before putting a boiled out or a new radiator in the vehicle.I believe the root of your problems is in the cooling system and the vapor lock issue is being caused by this.