Air Cleaner Valves

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altayd9
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Air Cleaner Valves

Post by altayd9 »

I’m trying to piece together my rat eaten 85 Grand Wagoneers and almost every vacuum line has been replaced except I’m missing lines and valves from the air cleaner and I can’t figure out what the Vacuum Check valve and the Reverse Delay valve are. It’s especially difficult to find anything about the reverse delay valve online so I don’t really know where to buy these things. I bought some sort of check valve from Napa, doesn’t look the same but I think it should work but I can’t find the Reverse delay anywhere, anyone know where I can find one of those things?
'85 Grand Wagoneer and '96 LS400
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tgreese
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Re: Air Cleaner Valves

Post by tgreese »

The R/Delay valves are little plastic pucks with a nipple on each side. My understanding is they impart a delay to the vacuum signal from a change in one direction. I'd imagine they have a pair of orifices inside with a flap valve over one. The orifice with the flap closes to a pressure change in one direction and opens in the other.

Can't help you specifically, but I did try a search on IFSJA and here and came up with many old posts with information.
https://www.bing.com/search?q=site%3Aif ... lay+valves
https://www.bing.com/search?q=site%3Afs ... lay+valves

You can also look in the parts books at www.oljeep.com to find the Jeep part number for these valves, and search the internet for the number plus "Jeep."

Unlikely some random vacuum check valve will work unless it's offered as a direct substitute for the Jeep PN that you need.

This is what I would do if it were my Jeep and I needed the part. All part of the work of owning an old car.

If no luck there, post on the WTB (want to buy) forum here for used examples of what you need.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
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letank
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Re: Air Cleaner Valves

Post by letank »

The R/delay valve prevents the vacuum from bleeding when the engine is turned off. Basically, it keeps the flapper(s) of the air cleaner opened, the from from the heater stove and the one that prevent the gas vapor from being release into the air - when the engine is warm it prevents a rich restart.

Is this one of them? the plastic one , for my 85

Image
Last edited by letank on Tue Jul 06, 2021 9:41 am, edited 1 time in total.
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)
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tgreese
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Re: Air Cleaner Valves

Post by tgreese »

Interesting. It's a long delay - the doors stay open once they are open, at least until the vacuum bleeds off from leakage somewhere, or an intentional bleed in the vacuum motor. This applies to the TAC (thermostatic air cleaner) and vapor recovery door. Look here - https://oljeep.com/gw/vac/85/85_FSJ-Vac ... on-360.jpg

The OP also mentions the "vacuum check valve" which appears to be upstream of the TAC temperature sensor which is located in the air cleaner. Any idea about that?

I would mention to the OP that the emissions system changed every year in that era, and aftermarket parts support will be spotty at best, more likely unobtainable. AMC did not build a lot of vehicles compared to say Ford and Chevy, and there will be virtually no market for a lot of these unusual and low-volume parts.

JMO - I would look at the parts forums here and at IFSJA for Jeeps from this era that are being parted out. That would be the way to get all this stuff if it's now missing.

If you eliminate the carburetor by going with some aftermarket fuel injection system, the need for these parts is gone. The TAC might have some benefit with fuel injection, but the need for vapor recovery from the carburetor is 100% gone. If you live in a temperate climate, the TAC is redundant anyway.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

letank
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Joined: Wed Oct 03, 2012 9:16 pm
Location: SF bay area

Re: Air Cleaner Valves

Post by letank »

tgreese wrote: Tue Jul 06, 2021 8:00 am
The OP also mentions the "vacuum check valve" which appears to be upstream of the TAC temperature sensor which is located in the air cleaner. Any idea about that?
yes, it is a part that avail. I had the specs somewhere, mine is leaking a bit of vacuum, you can bypass it, unless you drive in very cold weather... Will add pict shortly of one that could be a candidate, duralast E108 (this is a very old ref)

Image
Image

Image

3/4" spacing

tgreese wrote: Tue Jul 06, 2021 8:00 amI would mention to the OP that the emissions system changed every year in that era, and aftermarket parts support will be spotty at best, more likely unobtainable. AMC did not build a lot of vehicles compared to say Ford and Chevy, and there will be virtually no market for a lot of these unusual and low-volume parts.
Very good point that emission changed almost on a yearly basis.

I was looking at my set up because I do not have the EGR dump valve, and did not want to add confusion, you can check the 82 parts manual on Tom's site, and it matches my 85 set up that passes smog.

White and Grey valve J323 5938 as per my pict above for the heater flap, White and Yellow J323 7141 for emission flap of the air filter and Black and Purple for the EGR J323 6284. I do not have the VSV valve which has a White and Purple J323 6285. Pages 1512 and 1522 for the 82 TSM.

No ref on the little check valve in the parts ... looks similar to the one found on hot tub that control the air operated knobs.


added a better pict
Image

you can see in the background the EGR delay valve circled, along with the 2 nipples on the air cleaner for the thermostatic signal for the EGR

Image

for some reasons those picts are tiny, they are in my engine bits link below
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)
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tgreese
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Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Air Cleaner Valves

Post by tgreese »

Suspect he means this guy:

Image
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Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
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