70' GTX Air Grabber Question

[Curly]

Last Fall I received my 70' GTX back from having engine work done. Being in Chicago, I hadn't driven it much since bringing it home and now that the weather is nice I brought it out only to find the Air Grabber isn't working (or the hood mounter turn signals Grrr). I checked into the Air Grabber plumbing and found a splice was done with a plastic drinking straw in one of the air lines going to the actuator. I replaced that mess and found it still not working. Looking further, it seems the spring actuator is also missing now.
My question is, will the Air Grabber not work if the spring is missing off the actuator? I suspect it won't, but I wanted to check with the experts
Thanks!

 

[RJRENTON]

IMO...
The N96 option on my '70 GTX, the open signal, vacuum, is applied to the rod end of the actuator. The spring causes the actuator, after the apply vacuum is allowed to bleed off, permits the actuator to retract closing the air grabber door. Vacuum is applied to the opposite side of the actuator to close the air grabber door when the dash mounted air grabber switch (which is really a valve) is set to close and holds the air grabber closed (like if you're caught in a rain storm so you do not saturate the air filter element). There is also a 12 volt solenoid under the dash's bottom edge, which opens the air grabber door when the engine is running and dumps the vacuum to the actuator allowing the spring to close the air grabber door on shut down even though the air grabber switch is on. I've found a person that rebuilds the vacuum actuator if yours does not operate. PM me for particulars if interested. There are several suppliers of the vacuum hoses, and the 12 volt solenoid valve and other parts if needed.....not inexpensive though.
BOB RENTON

 

[Curly]

IMO...
The N96 option on my '70 GTX, the open signal, vacuum, is applied to the rod end of the actuator. The spring causes the actuator, after the apply vacuum is allowed to bleed off, permits the actuator to retract closing the air grabber door. Vacuum is applied to the opposite side of the actuator to close the air grabber door when the dash mounted air grabber switch (which is really a valve) is set to close and holds the air grabber closed (like if you're caught in a rain storm so you do not saturate the air filter element). There is also a 12 volt solenoid under the dash's bottom edge, which opens the air grabber door when the engine is running and dumps the vacuum to the actuator allowing the spring to close the air grabber door on shut down even though the air grabber switch is on. I've found a person that rebuilds the vacuum actuator if yours does not operate. PM me for particulars if interested. There are several suppliers of the vacuum hoses, and the 12 volt solenoid valve and other parts if needed.....not inexpensive though.
BOB RENTON

Bob,
Thanks for your detailed response! I haven't torn into anything yet, but have repaired and rerouted the underhood hoses coming out of the firewall so they're not spliced with a rolled up straw. I believe I have all of the hoses going to the right spots as I learned from the Air Grabber hose diagram.
With the hoses now hooked up, the hood does not open, but there seems to be active vacuum keeping it closed. Prior to this, I could pry it open and it would stay open, but now it won't open even when I try to pry it with my fingers. I haven't gone under the dash yet, but where is the solenoid located? I tried looking for it, but couldn't see it. Do I need to pull the lower dash apart?
I agree, those parts ARE pricey!
Thanks for your input and I do get down to the Decatur area on business with ADM and Tate & Lyle.

 

[RJRENTON]

Bob,
Thanks for your detailed response! I haven't torn into anything yet, but have repaired and rerouted the underhood hoses coming out of the firewall so they're not spliced with a rolled up straw. I believe I have all of the hoses going to the right spots as I learned from the Air Grabber hose diagram.
With the hoses now hooked up, the hood does not open, but there seems to be active vacuum keeping it closed. Prior to this, I could pry it open and it would stay open, but now it won't open even when I try to pry it with my fingers. I haven't gone under the dash yet, but where is the solenoid located? I tried looking for it, but couldn't see it. Do I need to pull the lower dash apart?
I agree, those parts ARE pricey!
Thanks for your input and I do get down to the Decatur area on business with ADM and Tate & Lyle.

The air grabbers vacuum source is a fitting on the intake manifold which goes to the check valve on the vacuum resevour (looks like a tomato juice can on the fire wall). From there the vacuum goes to the dash mounted air grabber switch (valve) and to the solenoid valve. The solenoid valve is mounted under the instrument panel near the tilt out ash tray, on the top side of the instrument panel's bottom ledge. It is secured to the ledge with a small screw, accessible from the bottom of the instrument panel's bottom ledge. There is one light green colored wire (12 volt switched source) and the ground is thru the mounting screw. Two hoses go to the solenoid valve.
If, with the engine running, the air grabber switch up (on), solenoid energized, the vacuum should be on the rod side of the actuator and the air grabber door should open.....if all the hoses are in the right location. Test to make sure the hoses at the actuator are not reversed, which would hold the door closed. If vacuum is on the rod end, and the rod does not extend, the actuator may be bad. They can be rebuilt. Try :
www.n96airgrabber.com Wilson Productions Inc Call or e-mail him for pricing or info.
FYI....I did contract engineering work for ADM Glycols maintenance department on Brush College Rd
Let me know how you make out.
BOB RENTON

 

[kiwigtx]

I checked into the Air Grabber plumbing and found a splice was done with a plastic drinking straw in one of the air lines going to the actuator.

A plastic drinking straw??? Someone needs their *** kicked....hard.

 

[Curly]

A plastic drinking straw??? Someone needs their *** kicked....hard.

Yeah, I couldn't believe it either. You can hide a lot of sins with plastic conduit and I wish that was the solution to the problem, but it's taking a little more effort, but that's the fun of it!
Cheers!

 

[Curly]

The air grabbers vacuum source is a fitting on the intake manifold which goes to the check valve on the vacuum resevour (looks like a tomato juice can on the fire wall). From there the vacuum goes to the dash mounted air grabber switch (valve) and to the solenoid valve. The solenoid valve is mounted under the instrument panel near the tilt out ash tray, on the top side of the instrument panel's bottom ledge. It is secured to the ledge with a small screw, accessible from the bottom of the instrument panel's bottom ledge. There is one light green colored wire (12 volt switched source) and the ground is thru the mounting screw. Two hoses go to the solenoid valve.
If, with the engine running, the air grabber switch up (on), solenoid energized, the vacuum should be on the rod side of the actuator and the air grabber door should open.....if all the hoses are in the right location. Test to make sure the hoses at the actuator are not reversed, which would hold the door closed. If vacuum is on the rod end, and the rod does not extend, the actuator may be bad. They can be rebuilt. Try :
www.n96airgrabber.com Wilson Productions Inc Call or e-mail him for pricing or info.
FYI....I did contract engineering work for ADM Glycols maintenance department on Brush College Rd
Let me know how you make out.
BOB RENTON

Thanks again for the info Bob. I think they took off the hood and didn't pay attention to all of the hoses and hood mounted turn signal wires until the hood was in the air. Then, just cut or pulled them without knowing the routing when they put it back together. I'll play around with it some more this week and see if I can get it to work without spending $$$, but I wouldn't mind getting a new set of hoses and routing them the correct way. Since the solenoid seems easy to locate that will make it easier rather tearing the dash apart.
Does it matter which fitting I use on the firewall mounted reservoir? I wouldn't think so.

I used to supply ADM Transportation with DEF, but I still work with the Vitamin E Plant, SFI, West Plant Extraction & West Refinery. Thanks again!

 

[Curly]

The air grabbers vacuum source is a fitting on the intake manifold which goes to the check valve on the vacuum resevour (looks like a tomato juice can on the fire wall). From there the vacuum goes to the dash mounted air grabber switch (valve) and to the solenoid valve. The solenoid valve is mounted under the instrument panel near the tilt out ash tray, on the top side of the instrument panel's bottom ledge. It is secured to the ledge with a small screw, accessible from the bottom of the instrument panel's bottom ledge. There is one light green colored wire (12 volt switched source) and the ground is thru the mounting screw. Two hoses go to the solenoid valve.
If, with the engine running, the air grabber switch up (on), solenoid energized, the vacuum should be on the rod side of the actuator and the air grabber door should open.....if all the hoses are in the right location. Test to make sure the hoses at the actuator are not reversed, which would hold the door closed. If vacuum is on the rod end, and the rod does not extend, the actuator may be bad. They can be rebuilt. Try :
www.n96airgrabber.com Wilson Productions Inc Call or e-mail him for pricing or info.
FYI....I did contract engineering work for ADM Glycols maintenance department on Brush College Rd
Let me know how you make out.
BOB RENTON

BTW, I just looked at your GTX and it's gorgeous! Plus, it's a 4 speed! I was trying to find a 4 speed when I was looking for mine, but there were only 727s available so that's what I got. I'll post some pics soon.

 

[RJRENTON]

Thanks again for the info Bob. I think they took off the hood and didn't pay attention to all of the hoses and hood mounted turn signal wires until the hood was in the air. Then, just cut or pulled them without knowing the routing when they put it back together. I'll play around with it some more this week and see if I can get it to work without spending $$$, but I wouldn't mind getting a new set of hoses and routing them the correct way. Since the solenoid seems easy to locate that will make it easier rather tearing the dash apart.
Does it matter which fitting I use on the firewall mounted reservoir? I wouldn't think so.

I used to supply ADM Transportation with DEF, but I still work with the Vitamin E Plant, SFI, West Plant Extraction & West Refinery. Thanks again!

Curly,
Thanks for the update.....re the hose connections on the vacuum resevour, the fitting has a one way check valve as part of the connection. This means vacuum can be maintained in the resevour When the engine is shut down. I believe the vacuum source connection should be to the center port of the check valve. As my car is in storage, due to the Covid 19 issues and no local car shows, I'm going by memory. There are several sources for new vacuum hoses, should you decide to replace your old hoses. Write again if I can help further.
BOB RENTON

 

[RJRENTON]

Curly,
According to Galen Govier's white book, in 1970 there were 678 GTXs made with the six barrel engine. Of the 678 cars built, 328 were automatic transmission cars and 350 were built with 4 speeds (one of the 350 ever made). Mine was built the 3rd week of November 1969 at the Lynch Road plant. The car also has the A34 super track pack option front power disc brakes, max cooling package, and the Dana 60 rear with 4.10:1 gears, N96 air grabber, power steering, rear window defogger, AM only radio....ive owned it gor 35+ years. Thanks for the comments.
BOB RENTON

 

[kiwigtx]

Thanks again for the info Bob. I think they took off the hood and didn't pay attention to all of the hoses and hood mounted turn signal wires until the hood was in the air. Then, just cut or pulled them without knowing the routing when they put it back together. I'll play around with it some more this week and see if I can get it to work without spending $$$, but I wouldn't mind getting a new set of hoses and routing them the correct way. Since the solenoid seems easy to locate that will make it easier rather tearing the dash apart.
Does it matter which fitting I use on the firewall mounted reservoir? I wouldn't think so.

I used to supply ADM Transportation with DEF, but I still work with the Vitamin E Plant, SFI, West Plant Extraction & West Refinery. Thanks again!

Here is a diagram which I saved a few years ago...it should help as long as you have the original colour-coded hoses...

Good luck.

 

[RJRENTON]

Here is a diagram which I saved a few years ago...it should help as long as you have the original colour-coded hoses...

View attachment 973941

Good luck.

Thank you for your information....I could not find my copy of the same in time to post it. I did make a schematic diagram of the hose connections and components using ISA (Instrument Society of America) symbology. Unless the reader understood ISA symbols it would be confusing, so I did not post it.
BOB RENTON