viven44 Posted February 22 Author Share Posted February 22 Nope It's missing entirely. That's why it was overheating and the idiots pulled the thermostat hoping it would help. But nothing is going to help the water pump push if the impeller is not closed off. Man, i'm glad you made me do this timing set, else I would not have found this issue. Thanks for your teaching "service"! Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 22 Share Posted February 22 Man, i'm glad you made me do this timing set, else I would not have found this issue. Thanks for your teaching "service"! I do what I can with my superpowers.... Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 22 Share Posted February 22 Wow, did not know that!! I will look more into this. I'll see how "Big Blue 2WD" is hooked up and copy that. Still has the emissions and all vacuum connection on it so I'm sure it will be a good reference. Can i use the same thermal switch that will control EGR ? Edit : Just realized that the Edelbrock carb is on "Big Blue 2WD".. i.e. its ported vacuum is connected to distributor. Look at the routing sticker. You will see VREST in one of the lines going to the thermal switch. If the coolant hits 220 the port shifts to full manifold vacuum and the advance plate gets pulled in more. Which brings the timing up and the idle is increased. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 22 Share Posted February 22 Look at the routing sticker. You will see VREST in one of the lines going to the thermal switch. If the coolant hits 220 the port shifts to full manifold vacuum and the advance plate gets pulled in more. Which brings the timing up and the idle is increased. 460 pickups are one of my "special interests" Along with material science, propellant chemistry, genetics and biology, long distance firearms and a few others. Way back in the early '70's they didn't have a category for autodidactic kids with an IQ over 160. I was "Profoundly-talented and gifted" but I couldn't get along with my peers.... Link to comment Share on other sites More sharing options...
viven44 Posted February 22 Author Share Posted February 22 460 pickups are one of my "special interests" Along with material science, propellant chemistry, genetics and biology, long distance firearms and a few others. Way back in the early '70's they didn't have a category for autodidactic kids with an IQ over 160. I was "Profoundly-talented and gifted" but I couldn't get along with my peers.... I sure am glad it is a special interest of yours!! I did check on the vacuum diagram on the truck. Looks like we have a 3 port vacuum valve, When cold it connects distributor to VREST (restricted vacuum) and when warm it connects distributor to full manifold vacuum. Not sure what restricted vacuum means on this truck. Maybe instead of VREST I could use ported vacuum from the edelbrock carb, which is No vacuum at Idle. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 22 Share Posted February 22 I sure am glad it is a special interest of yours!! I did check on the vacuum diagram on the truck. Looks like we have a 3 port vacuum valve, When cold it connects distributor to VREST (restricted vacuum) and when warm it connects distributor to full manifold vacuum. Not sure what restricted vacuum means on this truck. Maybe instead of VREST I could use ported vacuum from the edelbrock carb, which is No vacuum at Idle. VREST is a tiny winged plastic orifice that fits inline of the vacuum tube. Different colours denote different restrictions. Lots of people with automatics like ported vacuum, but it won't step up the idle if needed. I'm not sure why Ford never seemed to use ported. Many Autolite/Motorcraft carbs have an E port for the EGR, and I'm pretty sure that is ported. Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 22 Share Posted February 22 VREST is a tiny winged plastic orifice that fits inline of the vacuum tube. Different colours denote different restrictions. Lots of people with automatics like ported vacuum, but it won't step up the idle if needed. I'm not sure why Ford never seemed to use ported. Many Autolite/Motorcraft carbs have an E port for the EGR, and I'm pretty sure that is ported. If you put ported vacuum to where Ford had VREST then you won't have any vacuum at idle until the temp gets to HOT. Then, assuming you have the other port to manifold, you'll get a lot of vacuum and advance. But that might be enough to move you at a stop if you didn't have the brakes on hard as the idle would go up quite a bit. Link to comment Share on other sites More sharing options...
viven44 Posted February 22 Author Share Posted February 22 If you put ported vacuum to where Ford had VREST then you won't have any vacuum at idle until the temp gets to HOT. Then, assuming you have the other port to manifold, you'll get a lot of vacuum and advance. But that might be enough to move you at a stop if you didn't have the brakes on hard as the idle would go up quite a bit. Good point. It will take some tweaking. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 22 Share Posted February 22 If you put ported vacuum to where Ford had VREST then you won't have any vacuum at idle until the temp gets to HOT. Then, assuming you have the other port to manifold, you'll get a lot of vacuum and advance. But that might be enough to move you at a stop if you didn't have the brakes on hard as the idle would go up quite a bit. It's possible to tune for ported if you're going to recurve the distributor and install a new vacuum advance, but at that point one of Scotties custom curved distributors is only a few bucks away. But not back in the day when the advance was $15 and the springs 2. A Reman distributor was $35 and you only needed a welder or some brass tube from the hobby shop to tighten up the slot. Link to comment Share on other sites More sharing options...
viven44 Posted February 22 Author Share Posted February 22 If you put ported vacuum to where Ford had VREST then you won't have any vacuum at idle until the temp gets to HOT. Then, assuming you have the other port to manifold, you'll get a lot of vacuum and advance. But that might be enough to move you at a stop if you didn't have the brakes on hard as the idle would go up quite a bit. Immediate thoughts/solutions are to find a NOS vacuum restrictor or create a restriction in vacuum by using a smaller diameter hose, something like the one that runs to the HVAC controls, see if that provides sufficient restriction to keep the idle where it needs to be until warm. The other option is to use a vacuum delay valve between the VCV manifold port and distributor when hot so the change is not abrupt. Looks like I will need a vacuum delay valve to run EGR anyway so I need to find a source for it. Link to comment Share on other sites More sharing options...
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