are my enemy . i have a 72 200 c4 that had no vacuum lines at all. i think i figured some of them out, however, the shop manuals do not have a vacuum line diagram . anyway, it seems that i need one more manifold port so the vacuum tank could be hooked up using that 'tee' connector or check valve. any help would be greatly appreciated.
Personally, I would remove all vacuum lines, egr, etc. and place them gently in the trash can. I am not sure which ones you need for the 200, but for the 302, the only lines I have are one from the manifold Teed to the firewall (for heater doors) and the trans, Carb to vacuum advance on distributor, and a larger one from the valve cover to the front of the carb (can't remember what this is called, but it has a little valve in the plug that goes into the valve cover). That is it.
I'm not sure what that round thing is. Probably a check valve. Suck on one side & see if it is. Air should flow in one direction only if it is. Most vacuum cans have 2 lines. I'm guessing yours has only one. Therefore you need a check valve. If that is what it is, then it would be hooked up to a port on the manifold so that air is being sucked through it. On the other side you would T off and run one side to the canister and the other to your vacumm control line comming out of the firewall. All those vacuum lines running to the thermostat switch can be eliminated. Just run one line from the carb, over to the advance side of the distributor. You definately dont want the line from the manifold port to the distributor. Since manifold vacuum is constant, it will keep your distributor in the advanced or retarded mode depended on which side its hooked to. To determine which distributor port is the advance side, take the cap off and bump the engine over, I believe it turns clockwise. Then put a line one one of the ports and suck on the other end, if the points plate turns the opposite way of rotation, it is the advance side.
Not sure what a vaccum can or thermostatic switch is, my car don't have one. Two of the lines need to go down to your vaccum modulator on your transmission. The third needs to go to your distributor, although your guess is as good as mine on how to keep it from constantly sucking advance. That looks like a Carter YF carb, If I were in your postition I would stick a Carter RBS on it just for the ease of it. They have a place specifically for the vaccum advance to hook to on the side of the RBS. If you went that route you would need to plug off the 3rd vaccum port on the manifold and the EGR port on the carb. This is exactly how I've been running my car for the past 10,000+ miles without a problem. Don't know what that T thing is for. I would trash it. The more simple you can make the system, the better. This is just what works for me. May be diffrent for others. Edit: what is that line going to the base of the carburetor go to? Not the big one, the smaller one. If that's going to the distributor, I would just leave it alone and hook up your vaccum modulator and be on your way. By that diagram, your car appears to be much more complicated then mine. I would scrap all that junk unless it just absolutely has to be there for state inspection or something.
That lower line that Jamie pointed out looks like it should go to the distributor. It should have a vacuum on it, based on where it is coming from, and that vacuum should increase with rpms. Test it by starting it up and putting a finger over the hole, then revving it to see if the vacuum increases.
Chad, I have diagrams that show how to hose that thing up the correct way, but I cannot get my scanner to let me scan them at low enough quality to post them on here (100k). By the time I get the quality low enough to put on the forum, you cannot figure out what is in the picture. PM me (and give me your email address) if you would like the scans emailed to you. The scans are approx 1M each.
thanks guys. i think i will go mavaholic's route and get rid of the thing on the thermostat housing...it sure will clean things up. this 'tee' thing is a check valve - the center port only allows vacuum. however, the ports on this thing are bigger than the vacuum line coming from the firewall, but i can get it to work somehow. thanks again guys.
I PM'd you with scans of the "correct" setup. I would suggest that, like Jamie said, less is better unless state laws suggest otherwise (as my first post suggested). If you want the diagrams of the stock configuration, just PM me, and I will send them to you. I personally think you would be happier taking as much of that crap off as possible, and freeing up some space in your engine bay...
Personally,, if that mavaholic guy told me to suck on a hose I would find another message board. Actually,, he gives you excellant advice,, sounds simple,, but common sense application towards your car running right. Dan
Suck on it...oh, sorry, Listen to Mavaholic...or e-mail me for the diagrams for the original vacuum configuration..
I don't think any 72s had an EGR and the tranny vaccum modulator has only 1 line on non EGR cars. From the picture I don't see a EGR plate. Looks like I see a AC line so good chance those ports are for the climate controls, Vaccum Modulator, and maybe distributor. That line on the base plate of the carb may already go to the Distributor?? I know of a particular 72 that had a weird setup with a temp sensor that altered the distrubtor advance based on the outside air and a heated vaccum port( I could be wrong on exactly what it did since its been a while since I worked on that car but the system is in the Chiltons Service book) I too would loose as much as possible unless your going for a completely stock configuration.
yeah, i just want to get thing going right now. no stock for me...i am one of the guys that wants to put a 429 in it ? i am in the process of looking for a front clip so we (my dad and i) can start cuttin'. but right now, i just need a vehicle (it's getting pretty chilly on my bike). thanks again guys for the help.
The EGR valves started in '74 from what I have seen. Chad, to simplify what I said yesterday. Loose all the crap. Run one vaccum line to the modulator on the transmission (unless it has a place for 2), and run one from the base of the carb to the distributor. Toss the rest in the trash. Your car will run just fine as long as you have no vaccum leaks..
Yeah, what Jamie said (and a couple of the others on this thread), unless you want that diagram I scanned...it is really ugly
