Is it completely necessary to keep this in you heater hose. I believe it shuts the coolent flow off or on, it was a AC car, but not anymore. Is there another alternative to shutting your heat off on the inside? The headers already keep it toasty on the inside, but would like to keep the heater altogether for those chilly cruises.
control valve Joe, that is a hot water controll valve. It lets the hot water into the heater core when it gets a vacume signal to do so. I have taken them off in the past and just hook the hoses up 'straight'. Or you can hook up in acircle from the pump to the water manifold. If you get a gurgling sound after hooking up straight just reverse the hoses at the heater core. Naturally you will need to plug the vac hose if you take it off.
The valve may be faulty.NOS are hard to come by but are out there(at least for mine), I found some aftermarket ones for about $15.00 ea. on eBay,they look to be well made and are black,injection molded pieces.Not correct by a long shot but they should do the job and are easier to hide.
i took mine out and replaced the whole line and i gotta tell you its too hot. i gotta turn the heat almost all the way to cold for it to blow cool so you may not want to completely remove it. ive seen people put some type of manual valve in there from a hardware store so that you can turn the water flow off by 50% or whatever thats what im planning on doing
MAybe try NAPA. Even the GM NOS were made by an aftermarket company maybe 4-Seasons. I think brass type may still be available.
Check around junkyards. I believe some fords used a cable acuated version. it maybe a bypass style one though. (meaning water will still cirulate to the valve and bypass thru the valve back into the engine.) I think my 94 explorer has the cable acuated version, that bypasses back to the car.
So keep it? Thanks for the research on the P/N. I sounds like I should keep it and just replace it. I may need to show you guys one more pic. The round plastic ball that I believe is also apart of the heat/ac vacuum system is not hooked to the motor for vacuum. I did the 350/455 swap and came up short with places to hook up except still have room on the carb but may split it between that and my tranny. Just one more note, I did remove the AC and covered it with one of those American Graffiti covers. It did not say anything about removing the "ball cannister" Let me know, thanks.
Joe, there should be two vaccum hoses coming through the firewall into the engine compartmen tusually through a round rubber grommet). The longer one usually with a white stripe if it is original obviously has to go to the brass heater valve. The shorter hose with the same diameter goes to the smaller port on the plastic ball type valve. The other larger port on the ball should have a hose that goes on the port on the rear of the carb if it is a Qjet(if not your on your own). You need this setup for all heater/defrost controls to work at all.
Good deal Thanks for the descriptions, makes life alot clearer. Will hook up correctly. No Q-jet, runnin holley DP but will hook up for vac source. Do you think having no Vac hooked in this config would make the vac valve portion spliced in the heater hoses blow? Either way, will correct, thanks.
Had to revisit this thread. Is there a definate in out on the heater core? Or does it not matter? As long as the the heater control valve in on the intake line?
As for the heater core real simple. The ports are different size. The smaller hose that comes off the heater valve goes to the small port on the heater core which sould be the lower outboard port on the core. The bigger hose goes to the upper inboard port on the core. Factory specs for lengths on hose are 3/4"(larger) from water pump to core 42". 5/8" hose water valve to heater core 31". Short length of 5/8" hose frpm side of valve to intake fitting is 5.5". You may have to alter lengths slightly. Cut long first as big hose must not hit alternator or coil wire. You should have the foam pad and the metal strap as well to hold hose together.
On the same topic, I bypassed my heater core, (connected the 2 hoses together), but I now seem to have a partial overheat situation in hot weather at idle. My theory is that the core actually acts as a small radiator to remove engine heat. Any input on this would be greatly appreciated. I understand that there is a control valve so the manufacturer intended the flow to be cut off in hot weather, but with a modified engine creating more horsepower, (which means more heat), running coolant through the core may be the balance needed to maintain engine temp? I'm running a stock 4 row radiator, maybe I need an aluminum? Does anyone make a better water pump?
do you still have your fan shroud? how is your fan clutch? is the fan sticking about 1/4" outside of your shroud toward the engine? how tight does your shroud fit to the radiator? how many blades do you have on the fan? is your fan still stock? my guess is that your fan clutch is shot. (when engine is not running and cold there should be some a decent amount of resistance to turn the fan by hand. )
Good shroud, fan position is correct, using a flexalite w/ no clutch. The old 4 blade seemed to be too much drag at higher rpm. that may be the problem though, now that you mention it. People used to mention that it blew dust off the street when I revved the engine with the old 4 blade, but I dont notice it so much since I put the flexalite on.
I've never used a flex a lite, however I've heard many say go with a stock type fan after having problems like you describe with a flexalite. 7 blade if you can find it. 5 blade if thats all you have. so some searching on this board for flex a lite and you may find more info. the drag comes and goes with a good clutch. it will create drag when the engine is hot and will create less when the engine is cold. usually upon startup there will be a little more drag since the clutch fluid hasn't warmed up.
I use a 7 blade SS flex fan with no clutch and a stock shroud. no danger of it coming apart and going thru the radiator.
Very descriptive and helpful, here is the thing, the heater core sizes are right, the valve and intake are the right size, but the water pump spout is a 1/2"o No: using a reducer to make up for it? Other than that all is hooked up correctly now. Thanks
