Well,
My sister came through yet again and this ugly contraption arrived in the mail. I couldn't resist tampering. Here it is freshly delivered....
(http://i40.photobucket.com/albums/e210/ctefeh/Cntvalve01.jpg)
Pretty rank but I knew it looked bad when I bought it....but I got a pleasant surprise when I tested the solenoid and it fired! Note here as well when I used a test probe it didn't fire. Gave it 12 volts through normal wire and it worked no worries....
Volkenstein
So it disappeared into my shed, and with lots of penetrating oil and heaps of cursing, swearing and one broken screw (rusted badly), numerous ciggies and coffee I got to here....
(http://i40.photobucket.com/albums/e210/ctefeh/Cntvalve02.jpg)
The screws on this one were done up by a psycho at the F & S factory. The same nutjob that did up the others on my "real" spare as well. I'm
not joking, I have had to use strongest blade that will fit and really lean into it. They are all going to be replaced by cap screws with liberal doses of NickelKote Anti Seize!
Hmmm...pretty awful but at least the diaphragm assembly rubbers are in excellent shape....
Volkenstein.....
Here's a close up of what the diaphragm housing and doo-dads looked from the above picture.
(http://i40.photobucket.com/albums/e210/ctefeh/Cntvalve61.jpg)
Now armed with plenty of scouring pads, a 1/4 inch high speed steel lathe bit (for scraping), wire brushes and more coffee and ciggies it's time to clean, clean and clean....
I'll keep posting up the progress shots and lots of interesting little details like what size and free length the springs are, what size all the check valves are etc etc etc....
Stuff that isn't in the Bentley!
Enjoy
Volkenstein
Hiya Stein,
You know, you continue to do all of us a great service with your "exploded pictures". They really are a great help. You deserve a handshake and a pat on the back. Thanks!
I have found it really pretty amazing that, as bad as these control valves can look on the outside, they are usually in darn good shape on the inside. Those little red triangular valve flappers are the critical components. I think Cobey is looking into getting them reproduced somehow.
Mike
1970 AS Bug
Thanks Mike!
Make mine a bourbon!
I'm finding that although it looks horrible, the more I clean the more it's just surface rubbish/buildup. I'd even go as far to say that it should work properly after a little TLC.
After looking at all the check valves, the one your solenoid punches (middle of the 2nd photo) will have the most wear out of the three.
They should be able to be replicated fairly easily once the material that it's made out of is known. Certainly not Nylon, maybe some form of PVC?
Cobey?
From my early impressions, the little rubber bellows on the end of the diaphragm would be a weak point. It's very thin and is constantly flexing.
Most of the other rubber parts are a lot thicker...
Anyway I'll keep posting as I go. What's the saying? Fools rush in where angels fear to tread :lol:
Volkenstein
Well,
I had some stray wisdom teeth ripped out and have more or less recovered so I got stuck into it again.
There are/were 4 problem areas with this CV.
1. Broken diaphragm housing screw, after some attempts I'm going to drill 'n' pick it out, hopefully.
2. Stuck adjuster screw. Whipped the cap into a lathe and after wrapping a shifter around a screw driver it budged. Making horrible metal on metal screeches it finally backed out. The cap threads are OK but the screw threads need picking clean.
3. There is a small passage in the main housing between the airfilter/exhaust filter thread and where the check valve on the adjuster assembly sits. Totally corroded shut. This is going to be finicky as the corrosion is pretty tough stuff and I'll have to find something of the correct diameter to drill/clean it out with.
4. The adjuster screw and locknut on the diaphragm assembly are rusted together. I've cleaned it up as best I can but another tricky area as you can't really afford to distort/damage this particular assembly (much!)
In the mean time it's been clean, clean & more clean with wire brushes, Dremel tools and scraping. I went to a glazier and got a 8mm thick piece of glass that engineers use as a surface plate so I can get all surfaces flat.
Also I have been reading the Earls plumbing catalogue I have......could be semi-bling time in one form or another. At least two types of their hoses have an inner support spring available for vacuum applications.....
And all those lovely anodised fittings....tasty....and they have some metric to AN adapters that may just thread into our ATF oil pump fittings.....
Later....with some pics
Volkenstein
Hiya Stein,
Hey! You know, you have not mentioned WHY you're attempting to revive this beast. Just for a spare?
In any event, if you should need parts, let me know. I have a box full of CVs and miscellaneous parts. Already sent one complete unit to Cobey.
Mike
1970 AS Bug
Mike,
Since I started investigating VW's suitable for my wife (who can't drive a manual) I just got interested in understanding the whole set-up so I can fix it if it breaks/goes wrong.
When things are great all is well, but it seems to me that changing from stock can be a little fraught with pain. I don't know for instance if Lee (68Autobug) ever had any luck with his weber. I drove a '69 that thumped savagely....and yet it shouldn't have. And it all seems to come back to the CV and how it works. So as a famous Canadian ex-pat scientist's TV show always started...."Why is it so"?
Lastly, given some spares are rare as hens teeth, I want to know what can and can't be fabricated in a pinch. It would be easier to buy a secondhand one for sure, but then if I don't know what to look for/test I may wind up with something just as bad.
I have a very good spare and this one was dirt cheap and horrible, so it will be my test mule after this exercise for stuff like measuring vacuum etc and also to see if 'bling' can be done without too much pain. Later (like in two years) I would like to drop on twin carbs, but still have everything function "just so".
OTOH, if I do something hideous....no harm done,I still have a functioning spare!
Hopefully it'll be of benefit to someone, somewhere, someday :D
Regards
Volkenstein
Still fooling around with the plastics shop to see what we can come up with. So far, the bits they have made up don't hold up under temp or lots of repeat usage.
Cobey,
Bummer. Do you know what material they are made out of? Know any German speakers that could write an e-mail to F & S (Sachs now)? :lol:
So, I have managed to get the broken screw out without hurting anything. Lot's of careful drilling, pick work, plier work and more incremental drilling.
Rotten little thing was practically welded in there by corrosion of the old bolt.
Anyway, I have bought zinc plated cap screws in M4, M5 and M6 size and trimmed them to suit. I also bought a 30mm long M4 machine screw which I'll cut the head off and cut an adjusting slot into as well and an M4 nut to replace the one I had to cut off.
Finding replacement sealing rings hasn't been easy. So far I've only managed to find the ring under the reducing valve cap. The "standard" size ring for the diaphragm half manifold intake is too thick. Still also looking for the solenoid ring and the two seals under the M6 screws that hold the diaphragm half to the main body.
I've scraped, cleaned and surfaced things ad nauseum and I'm almost ready to use some Rust Bullet. Particularly on the solenoid and diaphragm cover.
Sigh...and I still have to drill the passage from the bottom face of the reducing valve through to the filter passageway....
Sticky pix next week...
Volkenstein
Hi Sean,
I'm still putting My engine & things back together...
Engine is in, I was going to reuse the ATF fluid as it wasn't very old...
under 100kms... plus I added a NULON additive for ATF...
I even bought a new plastic bucket and covered it with clear plastic wrap,
but I've decided to buy some new ATF.. but not sure which one...
Bentley says DEXRON with a 'B' and many new cars these days have their Own ATF fluid...
I suppose DEXRON will be OK... so long as its red... lol
My 'spare' control valve looks new compared to that spare of Yours Sean.
My Son bought an engine trolley same as that in the Bentley manual.
Only problem was that I have a CB Performance extra sump on My engine
so it caused a small problem... I used MY alloy Crankshaft pulley to hold the crankshaft while My Son did up the Gland Nut on the flex plate up to 282ft lbs...
cheers
Lee Noonan 68AutoBug Australia
http://community.webshots.com/user/vw68autobug
Lee,
You've been in the wars lately....funny you should mention the Bentley as I am finding discrepancies or question marks (this is the Orange one..)
So...The little passage way...here is a pic, hopefully good. This was blocked almost all the way. I decided to check my pretty spare Control valve and it was blocked too!!
(http://i40.photobucket.com/albums/e210/ctefeh/CVport.jpg)
To clean this out was simpler than I thought. Forget drilling. What I did was pull a steel wire "hair" from an el cheapo steel scrubbing brush. This one had "crinkled" wires. Grip it with a pair of needle nose pliers leaving about 6mm (1/4") at right angles to the pliers and wrap/cut the rest. Insert it from the air filter entry and you should be able to poke it through. Go back and forth and let the "crinkle" of the wire clear the hole.
I did this from the other side as well just to make sure.
Enjoy
Volkenstein
All,
My wife shattered her wrist about 2 1/2 weeks ago :cry: so I've been rather busy playing house hubby and Mr Do Everything....still, she is on the mend now and I had a chance to do some more....
Sprung a leak in my carby so I grabbed the top off my spare 34 Pict-3 and ripped out the inlet fitting and made up a screw in one and fitted it all up. Soaked up some spare time....but moving right along...
No pics this time as it has been just Rust Bullet-ing various steel bits and pieces (CV and the servo, some brackets and odds and sods). That's all done and I've masked up the CV parts I'm going to spray.
Finished off the diaphragm adjusting screw and have made some washers to replace some missing ones.
Hopefully the temperature will get above freezing over the weekend and allow me to paint....
Volkenstein
All,
So did the Rustbullet thing on various bits and pieces...
(http://i40.photobucket.com/albums/e210/ctefeh/Rustbullet.jpg)
I painted the solenoid, diaphragm cover and the main body halves and laid it all out again ready to assemble...
(http://i40.photobucket.com/albums/e210/ctefeh/CVstart.jpg)
First I put the filter and washer on the body with a bit of Permatex No 3 sealing the body/washer/filter.
Next was the solenoid check valve spring, the check valve and then the rubber ring followed by the steel retainer (lipped section facing the check valve), the large spring and popped the sealing ring into it's place and put the solenoid on with some cap screws.
Next I popped in the two bolt sealing rings and the O-ring along with the plastic locator piece. Into the diaphragm housing I put the check valve and spring into it's place.
I dry assembled and could see daylight and some gaps I wasn't happy with so I laid on Permatex again very carefully.
(http://i40.photobucket.com/albums/e210/ctefeh/CVPreshot.jpg)
(http://i40.photobucket.com/albums/e210/ctefeh/CVMain002.jpg)
Volkenstein
So,
After aligning the diaphragm cover, I tightened the two screws securing it to the main body. What's left is now the diaphragm and the modulating section to be reassembled.
(http://i40.photobucket.com/albums/e210/ctefeh/CVMain003.jpg)
Starting with the diaphragm cover, the plastic spacer thingy goes in first, then the rubber washer. The small end of the diaphragm is pushed through the steel "brace" or ice-cream cone doohickey and seated.
What you should have is the steel doohickey sandwiched between the small and large rubber ends. Drop this into the housing, screw in the adjuster rod and nut and then place the spring on top and finally do the cover up. Last but not least is the brass vacuum fitting and it's washer.
Next is getting that .30/.40 mm setting for the plastic spacer poking into the modulator side. I cut a .4mm depth into a brass slug and used that to set the gap. All looking OK thus far.
So onto the modulator and psychotic episodes. Drop the check valve into the bore with the protrusion facing up. Pop in the O-ring at the top. Put one cup fitting on top, fit the spring into this and pop the other cup on top of that. Next is the cap. I have left two full threads exposed as specified in most of my manuals.
Now the need for hospital grade sedatives...time to fit the spring washer into it's groove to hold the cap down. 4th attempt and it finally went. I used a medium screwdriver to help but it is not a fun job......
All assembled with the brass slug I used to set the gap.
(http://i40.photobucket.com/albums/e210/ctefeh/CVassembled.jpg)
Volkenstein
Here we are after fitting the waisted rubber mounts and bracket...
Looks lurvly don't it...but does it work?
(http://i40.photobucket.com/albums/e210/ctefeh/CVFinished.jpg)
NO. If I fitted this as it is now, I reckon it would thump.
I'll explain. On my other two (on Klaus and my spare) when I push the diaphragm down and place my finger over the brass vacuum fitting, the diaphragm maintains position. Not so on this one.
I could hear air being pumped/sucked. The diaphragm piece itself is OK.
Maybe I screwed up with the Rustbullet? I removed it all from the diaphragm cover (the underside) and while I was at it I smeared permatex on the underside of the steel doohickey and on the underside of the rubber washer. Re-assembled and still not holding vacuum.
For my next trick, when I dissassembled it again, the Permatex ring on the underside of the steel doohickey was untouched!!
I made up two paper gaskets .4mm thick and placed them above and below the large section of the diaphragm as the Permatex under the rubber washer was well and truly spread. Put it all back together and this time it was much better, but I still have a leak there.
It got too cold and I need to find some thicker gasket material.
What happened?? I think my cleaning of all the corrosion has actually contributed to the problem. The rubber washer and the larger of the two diaphragm rubbers have been well and truly crushed with age. They don't leak by themselves but need to be properly spaced to seal.
I'll post back on what I finally end up with as a solution......
Is there a moral?? Well, never ever buy a corroded one if you need a spare :lol:
Enjoy
Volkenstein
I didn't think that would end up looking like that Sean...
Very Good...
My Control valve is mostly Green....
I'm wondering now that If I have to have the engine lid open at the top in the summer... what effect will rain have on the little breather on the control valve....
Should I use a right angle fitting so it sits upright....
or have it sitting up under the top of the engine bay....??
Have You ever tried to drive with the small vacuum hose off..???
It takes ages for the clutch to release....
Lee Noonan http://community.webshots.com/user.vw68autobug
Lee,
Provided all the hoses are hooked up, the rain won't affect the CV that much. What I would do is use RTV sealer around where your adjuster screw is, on the cap as water can seep down until it hit's the O-ring and cause "calcification". The diaphragm sit's upside down in the "normal" position so water won't leach into it.
The brass spigot has a tiny, tiny "jet" in it. Any rubbish could easily block it.
After all my mucking around and comparing various schematics, leaving the hose off the brass spigot will delay clutch engagement by almost a century! When the modulator isn't functioning (via the diaphragm) the only place for air to enter the CV/servo is via that teensy little port near the modulator check valve (I photo'd it in the first "page" of this post).
When you accelerate, vacuum from the carb venturi causes the diaphragm to push the modulator check valve off it's seat, and filtered air is drawn in quickly allowing the servo to release the clutch.
The adjuster screw for your shift engagement speed regulates how far and fast the check valve is raised and closed.
Which I guess is another way of saying....even a restricted "T" piece from manifold vacuum is not as VW intended :lol: But the proper fix may well be impossible if you don't have a place to fit a venturi vacuum fitting on your carb of choice.......
That's my random thoughts anyway.....
Volkenstein
All,
So I pulled it apart to check what had happened with the twin paper gaskets.....
(http://i40.photobucket.com/albums/e210/ctefeh/CVFailed.jpg)
The bottom right gasket shows no sign of being compressed by the steel ice cream cone. The bottom rubber seal got a bit more compressed and look where the cap isn't contacting the body.....
Volkenstein
All,
So I ditched the two paper gaskets and found some spare rubber material I used to make a transmission gasket. It was 1.3mm thick.
So I cut a piece 71mm in outside diameter and 61 internal diameter.
This I placed on top of the large diaphragm rubber and didn't use the two paper gaskets.....
This time it was worse :cry: . The diaphragm steel cap started to bow as I tightened the little cap screws so that was the end of that.
After a bit more thought and measuring I seriously believe I'll be making a new thinner bottom rubber piece (bringing the steel support closer to it's upper seating lip), using a paper gasket on top of the diaphragm rubber and running RTV around the cap sealing lip and around the outside edge of the large diaphragm rubber......
Volkenstein
All,
Took it apart again, and measured various depths and stuff. By my calculations, the ice cream cone doohickey seals on the bottom seal, and the top diaphragm rubber is held against upper section's lip by the cover plate. Self centering if you like.
So I threw away all my gaskets and placed the seal/cone/diaphragm assembly in the housing and ran a thickish bead of RTV around the circumference if the diaphragm rubber (which I noticed, has clearance between it and the alloy housing...something that definitely isn't there on my other spare...so maybe the rubber shrunk back?).
Carefully put the cover on and waited about 1 hour then tested with a Mityvac pump. Much better. the diaphragm moves with 5 in/Hg vacuum and moves slowly back to it's resting position.
I'll check the RTV seal as I may have not made it thick enough, and I'll see if I can narrow down exactly where it's allowing air in.
Volkenstein
All,
I took the cap off and the RTV had completely sealed the diaphragm/cap/support....spent the next hour picking it all out.
I had a look at the diaphgrams and there are no pin holes, so my next area of sealing will be around the plate that the adjusting screw nut is on.
I think I can put my ciggie habit to good use by blowing smoke into the brass spigot (when I've reassembled it), sealing it off and then pressing down....maybe I'll be able to detect where it's leaking....maybe not.
Curil K2 is going to be the weapon of choice for the upper plate, RTV around the diaphragm again.....
Volkenstein
I didn't really believe that you would ever get all those bits back together the correct way Sean....
the small vacuum hose came off My carby one day as I pulled onto the highway....
I soon pulled back off as it took ages for the clutch to engage....
and naturally, every time I touched the gearlever...
it took longer....
Its really unbelieveable that these things have lasted so long.....
cheers
Lee -- 68Autobug --
http://community.webshots.com/user/vw68autobug
Lee,
Absolutely, even this one as cruddy as it was still had a working solenoid, and the internals were in fair shape.
For a 37 year old weather exposed thing, it's in remarkably good shape internally. The only machanical wear is on the check valve face that the solenoid plunger hits and the reducing unit check valve where the plastic spacer pokes into it. Nothing I can do about the former, but a little re-adjustment of the diaphragm screw takes care of the latter.
I reckon I've been a contributor to the current problem by taking it completely apart and disturbing things! :lol:
There's a post with schematics by a UK guy with a 356? that explains very clearly what happens with your vacuum and the tiny compensator port. I'll be taking some vac measurements for sure off Klaus when I'm able.
Regards
Sean
I wonder if thats the guy with a replica 356 in the UK... He can't drive a manual, because of a medical injury, so He had a company install the Autostick into the car with a brand new engine....
The company installed a dual ATF/engine oil pump, without changing the oil seals.... and the ATF ended up in the engine.... car didn't go very far...
The New engine wouldn't like running on ATF either...
From what I've read, the maximum oil pressure from the engine is 28 PSI
and the maximum pressure for the ATF pump is 52.6 PSI...
From what I've read so far Sean, You have done more measurements etc than anyone.. anywhere... as for most people the Autostick components are a bit of a mystery....
cheers
Lee Noonan -- 68AutoBug --
http://community.webshots.com/user/vw68autobug
Lee,
That's the guy, didn't realise he'd had an oil flood :shock: .
So on to tonights effort.
Got the Curil and sealed the diaphragm with that and put some on the reducer adjusting screw and nut while I was at it. More RTV around the diaphragm and button it all back up again.
A slight improvement, it returns to "rest" slower than before. Not much however. Reacts faster to the Mityvac vacuum as well, again not a great amount.....
Next time, it'll be the large rubber washer to body as well as re-doing all the rest.
Volkenstein
So,
After a month overseas getting a drinking problem, I've returned and dried out enough to hook in again!
Pulled it apart yet again and a fun hour it was picking the RTV out of every nook and cranny. The cover/diaphragm/support is fully sealed by the RTV so time to coat other things.
This time I did around the bottom rubber washer and put some on the underside of the large diaphragm, where the aluminium shaft is as well as sealing the two body joining screws.
This time, it reacts instantly to applied vacuum but still manages to return to rest. I've only got two places left and that's around the small diaphragm rubber. I think it's time I also ditched that bottom rubber washer as I think it has now retained the "crush" from the steel diaphragm support and probably is not sealing as good as it should.
Until later on
Volkenstein