Did a bit of work on my 73 SB electric AAR

[blues90]

First I added a 1/4" female and male connector in one of those VW plastic covers since I don't know what happened to the original plug , just slide heat shrink over and twisted and soldered the short wires I cut from a seat belt warning connector under the rear seat then heated the shrink to seal it . Now I can plug it and unplug it. Then I checked the heater it read 14 ohm from the base ground end to the red lead positive end. Don't know what it should read yet it seems to be ok.

Then I screwed it to 2 blocks of wood hung up side down over a old glass measuring cup and sprayed carb cleaner in the IAD side let it run though the oil bath side a few times then wet a blue shop towel with carb spray and fit in in each port to wipe any oil goop away a few times till clean . Plugged the oil bath side shop towel tilted the valve so the oil bath side was as low as possible then sprayed carb cleaner in the IAD side until it ran out and am letting it sit. I know the shop towel is not a seal yet is will at least allow the cleaner to work. The valve I could see through the IAD side looked clean so I/m hoping this will free it up. It will open cold yet when hot sticks , it warm enough say a 2 mile drive if I tap the side of the valve area it will almost close completely yet once it cools off it seems full open so it does move heater seems good hoping it begins to work .



This is what I found holds the idle at 1300 RPM once plug the line or tap the valve the idle is 1000 in park and about 900 in drive.

[Emeraldlion]

So honestly, in mostly warm weather does the aar do much of anything? Why not just delete it and cap the iad?

[raygreenwood]

[Emeraldlion]

I thought the aar was allowing additional air into the mix when cold or open at idle? This would make things leaner....I need to read again

[KTPhil]

[blues90]

I tried hanging the AAR upside down all day yesterday and today. I even plugged the oil bath end so the valve could soak hopefully cleaning it. The I put 12 volts to it and it did move yet never closed . I even tried to work the valve through the AAR /vacuum side and it was better yet once open it still would not close.

I ended up taking it apart , used a razor saw to cut slots about 1/4" apart and marked the position of the pipes to the base , removed the top / oil bath pipe from the top and got the valve out. I had to use fine grit wet /dry to polish the valve and bore , cleaned them out completely. The heater had a small amount of oil crud on it yet it is still intact and works. I filled the ceramic area with carb cleaner and let it soak took a small pointed new paint brush and got almost all the crud out.

The tough part for me was getting the oil bath fitting back into the top , I had to file a bit of the peens off to finally get it to seat. once I got it to seat I used a pointed punch to peen it secure.

There is no way on earth you can get all that old oil crud off without taking it apart , NO WAY !!!!!!!!!!!.

I marked the thermal clock springs position before taking it off. Once I had the valve and valves bore clean and polished it was easy to rotate. Now I have the valve together. I put it the freezer to see how far it moves real cold. While the heater is now drying well I'll place the valve in the heater power it up and see if it fully opens and if not see if adjusting the set screw position fixes that.

I need to drive it monday so I did start it with the IAD vacuum line plugged and the hose from the oil bath plugged . It did start yet I needed to give it a bit of gas for a few minutes till it would idle on it's own.

You do need it unless you feel like sitting there for 3 to 4 minutes till it will idle and it was 80 degrees F in the garage when I started it.

The valve in mine being a 73 square had a sort of key hole slot so one end is as large as the vacuum port then it becomes a straight slot . Right now at room temp with the thermal clock spring set where it was I can see just a small bit the the larger hole in the side of the valve as it closes it seems move toward the slot from the hole . I'll be happy if it starts and then shuts completely once it heats up . I would say the slot is quite enough for full vacuum have no idea why the larger hole or key hole shape was even done. Must be for very cold weather that I never see.

( Just to add , just took the valve out of the freezer and it is very close to the large hole on the key hole shaped slot looking through the vacuum side so it is for very cold temps.)

Once I cut the slots I used a tiny pair of channel locks to bend the tabs to remove the valve from the heater casing. I haven't decided how I will close them back up might use the same tool or a very small hammer.

This is not something I care to do again , I imagine anyone who tries this will find oil gunk that can't be cleaned out without taking this thing apart. I'll just see if mine closes fully once warm and opens at room temp., best I can do , has to be better than dealing with a 1300 RPM idle and that maybe I'll close maybe I won't because at 1300 RPM put in drive is not at all ideal.

[raygreenwood]

[blues90]

Yes Ray , I saw the original post where Intrinsic posted his repair then you followed up with more in depth photo's.

All I can say is the heater coil in mine was not to bad , didn't have much more than oil stains and a tiny bit of maybe oil flakes. No matter how careful I was carb cleaner still got in the coil area mainly in the metal bowl below the ceramic heat section. It still got hot with power applied and now that the valve moves it should close. I may need to adjust the position of the heater thermal spring more torward the closed position I will know once i set the valve into the heater and power it up before I close it up .I thought of drilling and tapping the flange rather than crimp it so i can take it apart yet i can do that later if needed . It does not seem the crimp has to be air tight yet it would be best if it were. on my valve I could not turn it enough to align the roll pin to remove the valve yet a bit of back and forth turning i could and that's were it was binding up and not closing , moves free now. stop to stop per the roll pin. Not really stops since the roll pin does not hit either end even out of the freezer.

I just hope it works as it should once I get it together.

[blues90]

I tested the AAR 6 times and let it cool each time , adjusted the spring so it would open sooner. Crimped the two housings together and made certain it was closed well and just ran a thin smear of fancy black RTV around the cuts I made. Tested it again right off the cars test point connector it closed again so I installed it and of course dropped on screw found the washer found another screw that fit metric thread. got it all back hose connected to the IAD vacuum port fired it up and the AAR was cold by the time I did. It seemed to take longer to close with the engine running even though the voltage was a bit higher and it did close yet still once I start it the idle picks up and hangs around 1200 RPM until the AAR is almost closed then I set the idle @ 900 RPM in park. Maybe it's the vacuum through the valve that does this or not driving it or having the engine lid off makes it take longer. I have no idea, none.

However the idle with the valve closed was 1100 RPM and dropping it to 900 just might make all the difference. I know one thing there are no vacuum leaks every single line I replaced and the trans modulator does not leak a drop. Plus it has new injector seals and runner boots.

All I have not done is replace the PCV lines to the heads yet I got clamps to make sure they seal and I looked at the ends saw no cracks at the heads or oil bath and the PCV line to IAD I replaced and clamped. Also want to clean the PCV if Auto--------zone ever gets the contact cleaner in that I paid for it's fast drying and plastic safe. Bugs me about the screw probably under the car or stuck somewhere where it fell yet not a big deal just a wasted hour searching for another.

[raygreenwood]

[blues90]

True , when I tested the AAR off the engine it didn't take much more than 5 minutes to close and the base and heater housing where almost to hot to touch even the pipe's were pretty warm . Installed on the engine running was a different story , it was not hot at all. Seems not only the aluminum mounting is a huge heat sink so is the air flow through the valve. The adjustment I did was only as much as the thermal springs lock screw thread diameter only made it close 1 minute sooner off the car.

At least it closes now. I just let the heater coil soak with carb cleaner filling the ceramic and within an hour it all evaporated, the coils looked clean . when I powered up the coil with the valve assembly out I got a slit second of a puff of smoke didn't see any build up on the coils probably carb cleaner residue left evaporating off . Didn't thing to use denature alcohol yet I had some felt carb spray did n't seem to leave any residue . At any rate the heater coils work and look clean and shiny.

[blues90]

What I mainly found to be the issue that causes the valve to bind was a very fine surface rust mostly on the valve bore since it's steel. The soaking with carb cleaner did remove the baked on oil yet it was the minute rust that slightly scores the valve yet mostly the steel bore as well as the valve shaft though the steel bore had rust that slightly scored the stainless valve shaft.

Seems to me the rust happens first then the scoring allows the oil to cling rather than pass through then as it clings the heat bakes it on.

You may prevent oil with a paper filter yet not moisture which IMHO is the culprit. The bore is what had the minute surface rust , if it had a stainless sleeve this might not happen even though stainless is still affected a bit my moisture it does not appear to rust.

If the oil had no scoring to cling to the oil would freely pass through and even lube the valve because when I watched the polished valve rotate in the polished bore with the heater powered up it would rotate slow than near the full closed position I could see the valve halt then jump rather than move steady. This may be that action of the thermal spring as each wrap become closer and rub /contact each other yet if the oil were to free flow on a rust and score free surface the oil would act as a lube for the valve and smooth out this action. Perhaps a moisture trap before the valve would prevent this or simply a stainless sleeve rather than bare steel bore.

I could see the carb cleaner did remove the baked on oil , I could see it each time I flushed the valve and let it drain out and saw there was no oil in the bore on the valve . What I did see was the rust in the bore and in the area the valve shaft fits through as well as the bottom of the bore had fine rust colored staining it was none the less abrasive enough over the years to score the stainless valve over years of cycling say 90 degrees CW and CCW . It was the bottom of the valve and the stem where it fit through the smaller steel bore that were scored not the sides of the valve that was just small easy to polish out rings.

It does seem to take years for this to happen and the scoring does not take much to remove so the polishing does not remove much metal the valve in the bore is a very close fit. All it takes is a bit of surface rust to develop in the steel bore to begin this process.

Don't care if it's oil bath or paper moisture will still flow though the valve.

[mondshine]

I posted an AAR hack last year when I modified an electrically heated Type 3 AAR for use on my CIS injected Thing.
Everything I did could be applied for use on a Type 3, and this modification makes it possible to completely disassemble the thing for clean-lube-adjust.
This AAR has worked perfectly for over a year.