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Hi, guys:

After two years of non-running, I have my 411 back on the road. It now has new strut inserts up front, a new steering damper, new NOS speedometer, new fuel lines and electronic ignition.

My questions are these:

1. when I fill up the car, it smells gassy. It's not a leaking fuel line. Mine's a '71 with California emissions, so it has a charcoal cannister that might be bad. certainly the big 19mm (?) hose that runs from the fuel filler to the cannister is hard as rock. My thought is that the section of rubber hose that connects the metal filler tube to the tank is crummy. Will a piece of this hose from, say, a Type 3 fit my car?

2. Anyone know where I can find the package shelf that goes below the back window? This is listed in the accessory catalogue, but I've never seen one. There are tell-tale screw holes in my package area that tell me that there was once one on my car, and I'd love to have it back.

Thanks, guys! It's good to be back in my 411 after way too long a time!

- Justin

Hello Justin! Normally the leakage of fuel after gassing up is from several areas.
(1) Yes it could be the main filler hose. Usually even at thisage, its a matter of clamping. Yes, you can use one from a late typ3 for diamter, but Am not sure about length. You canalso go to large hose supply companies and get a comparable red multi ply fire/water hose that should also work for at least a few years.
(2) there are also several vent lines on the passenger side in the trunk...partly under the fender and partly under the passenger side acces hole under the carpet on the ledge in the trunk. These are the top fuel tank vapor vent and the small 3mm lines that also go into the charcoal cannister.
(3) Check the gasket around the fuel gauge sender under the lid and under the carpet.
(4) The worst offender is the 14mm loop hose that comes out of the fuel filler neck about 4" below where the gas cap is. This only leaks after fill up and when you are about 3/4 tank.

I have never in my life seen a parcel shelf for the back.
Question: do you have the pressed paperboard, leather grained cover that goes up against the back glass....the one with the slots in it that connects to teh outside rear quarter grills?
If not...That is what the row of screws under the back glass held on....not the package shelf. Ray

I'll check that 14 mm hose first - you're right that it usually smells gassy only after a fill-up and until the tank is about 3/4 full, then after that not at all.

The reason I think there was a package shelf was because I see little screw holes just below the rear quarter windows about 3" below the window. This is inline with a little lip on the backside of the rear seatback, indicating a shelf. I think I'll just fabricate my own!

-Justin

If you do not have the cardboard fascia that snugs up against the rear glass...with five to seven 1" slots running across its top...and...if you cansee the vent hole to the rear grills on each side...then the screws you are seeing are for the cardboard part you are missing.

You have to have that cardboard piece of your flow through ventilation system in the car does not duct properly. It leaves too much condensation at the bottom of the rear glass in the winter. Ray

Well !!! I have one of those package-tray things offered by VW as an accessory. It's more of a cover over that area behind the back seat rather than a package tray, and has it's own little lift-up door to access whatever junk you're trying to hide back there.

I'll take a picture of it tomorrow (it's at my shop) and post it in the next couple of days!

Gee.....maybe I should reproduce a few of them....


Travis

Cool! I actually built a tray for mine that ledges behind the back seat edge and right below the cardboard fascia in the back. Its covered with "mouse-furr". It's mainly a tray to hold the four 6.5" speakers in place. They both have polyfil behind them..but the center section I also have a lift lid and is partitioned so I can access the heater glow plugs. Ray

Well Ray, you've pretty much described this VW accessory to a 'T.' I posted the photos in the 411/412 gallery on theSamba, but the photos are below. I just plunked it into the area behind the seat for the photos, but I am sure that you are supposed to actually remove the rear seatback to properly install it.....and yes, it should sit on that little ledge behind the rear seatback.

This particular one has an injection-molded vinyl covering, and has started to split in a couple of areas, which is why I have never really used it (appearance). I have thought about reproducing it though. I don't know if there would be enough interest for them.

Anyway, here's the photos.


Travis

Oh, I forgot to mention.......aside from the support from that ledge behind the seatback, and resting along the rubber strip at the bottom of the carboard facia at the rear edge, there are no support strips along the sides that were screwed in place.

Justinshelton: do you have the original carpeting behind the seatback? There should also be carpet along each side below the quarter windows. In my two-door model 412 there are two screws along the top edges of these side carpet panels to hold them in place. Maybe this is what the screw holes are for that you had mentioned.......unless your carpeting is already in-place, and you have extra holes (??).


Travis

Sweet! Are those the original seats? I have never seen cloth seats in a type 4.
Mine is similar but a bit different. My door/lid is only about one foot wide, because the areas on the sides I made to hold speakers angled forward at 10*.

The speaker areas are recessed about 1" and have stainless screen arranged over them and then covered with cloth. It does not impede the sound...butspeakers are out of view...to deter theives and sun damage. So when the cloth covers are off the lid area appears raised.

Technically I lose all but a little of the storage area since the access panel is just to reach the heater....but the sound is superb. $11/412 have some of the best accoustics I have ever seen. Nice shape. Ray

Hey Ray,

Yes, they are the original seats, but I reupholstered those seats last fall. I used original GM fabric used in the mid-90's pickups and Cavalier models. I also installed seat heater kits in the two front seats. I did post pics here when I got it done. ( http://www.shoptalkforums.com/viewtopic ... ht=#830566 )

I kept my old covers for the pattern, and I recently made up a set of covers for Bill K., and sent them out a couple of weeks ago, including new rear map pockets and headrest covers. I guess he ended up with a reupholstered rear seat from Brian Fye, but Fye kept the front seats for his wagon. It's too bad, because I was unable to exactly match fabrics. Maybe we'll end up making new covers for the rear seat as well !

My car originally came with vinyl upholstery, but the cloth upholstery was an option....and I have found scraps of the blue cloth upholstery tucked here-and-there in the car......usually little squares that were stuffed in as an anti-vibration buffer. I think I still have a small piece of it on my desk at the shop.

I have a question for you Ray: (not that I mean to pirate this thread), but I have replaced all the fuel and vacuum lines in my 412, replaced the leaky pushrod tube seals, and replaced the distributor with a rebuilt unit, but I still get a bit of bucking happening during decelleration.....what is typically the cause for this? My MPS does hold vacuum, too.


Travis

Its a combination of things...no one particular part being the ugliest....but all contributing to the "bucking".
(1) one the automatic....the throttle positioning unit (that gold colored dashpot plunger) is part of it
(2) On any model with the PCV valve...that is a major part of it. Crack the guts out of the PCV...and put afixed restriction in the 12mm line. About 3-4mm is fine. Then re-adjust idle and mixture .
(3) After the PCV mod...a proper adjustment of whichever deceleration valve system (manual vacuum or electronic)
(4) The primary culprit is poor adjustment of the TPS.....and built in slop in the TPS. I have found that taking about .015"-.020" of slop out of the TPS....creates superb throttle response and gets rid of the vast majority of bucking
(5) After all of this...a slight adjustment to the outer throttle stop screw (the big outer plug) on the MPS...generally clecnhes it.

Other things that do not help...is if you have a wandering idle timing setting. If the mark jumps all over when you have the timing light on it and its at idle.....take out the dizzy and tighten a few things up in the guts.

The directions in every manual I have found for adjusting TPS...either suck or are just plain incorrect. There is also a modification that helps greatly if you have slop. If you need a direction for it...I can make you a short video. Let me know. Ray

Thanks Ray,

First off, the car is a 4-speed California-spec 2-door, so no dashpot for the automatic.
Secondly, I didn't remove the PCV guts, but rather, I drilled a 3mm hole in the bottom flapper valve -- I will properly complete this mod in the next few days.
Thirdly, the Throttle Valve Switch is NOS....but may be out of adjustment.

As I mentioned, the distrubutor is a remanufactured unit that I bought/replaced last year. I will check for a scattered timing pattern at idle tomorrow. Also, my pulley only has the '0' mark and the red line. Do I go by the Muir manual and time this to the red line at 3500 RPM with vacuum hoses removed, or is there a better way?

I have never adjusted an MPS before, and am still intimidated by what to do there. Any tips you have, or the video on the TPS would be great!


Travis

Its worth it to find exact TDC with the fan. The "0" is probably accurate. I would degree out the rest and make sure that 27 BTDC (the red mark ) is accurate as well. It probably is.

One thing I forgot to mention is that the factory timing method has flaws. Part of this is the sloppiness in the dizzy. Part is also the fact that when it is timed properly at 27 BTDC with hoses off. It tends to be too low for proper running at idle with hoses on.
What you would like to see at idle...say 900 rpm....is about 10-12 BTDC with a stable timing mark......meaning not jumping more than about 1/8" in either direction of the TDC notch. You can do better than that with some work...but that will suffice.

Yes....you need to complete the PCV valve mod. Its probably no t far from good enough the way you have it...but better safe than sorry.

Also, check you vacuum advance and retard chambers for no leakage.

Adding in some stops for the vacuum retard so it does not reatard too far...and adding in a stop for advance so it does not overadvance with hoses on will be key as well.

I am assuming that by NOS...you mean teh throttle valve switch has not been touched. It is then most assuredly in need of cleaning, and new o-ring for the TB and proper adjustment. I have also found that roughly 7 of 10 have excessive slop thatcan be modificed around. Ray

Well, I did some poking around the engine bay today...checking hoses and fixing a few things....and discovered that my auxillary air valve was not working, and was open in the 'cold' position all the time. So now I need to find another one. Now, would I be best to leave it in the closed 'hot' position?

Also, if my tach is accurate, I could not get it to idle less than 1200 RPM's with the idle mixture screw all the way in, and timed as you had suggested. Man, I just can't seem win easy. I did remove the throttle body (and cleaned it), as well as opening up the TVS and checking/cleaning, and checked the rubber cone-shaped seal to the plenum....still seemed flexible, so I smeared a bit of vaseline on the inner & outer surfaces before reinstalling just in case there were any leaks.

Anyone got another Auxillary Air Valve they can part with?


Travis

OK....you are now at the point where hundreds of others have been. The problem is this. You can't get it to idle down any further because you are already running too much air at idle.

This is NOT to say you are running generally too lean. These two functions are not the same. A smal or untimely vacuum leak at idle rpm will cause lack of control of idle and baseline fuel mixture at idle rpm.
However...as rpm increases...this small vacuum leak may not increase its airflow great enough to cause undue lean condition.
In fact...quite the opposite...if its a vacuum leak that increases while accelerating.

Bear this in mind: On a carburetted car or even a car with L-jet instead of D-jet...a vacuum leak causes LEAN running. This is because the air thatcomes in through the leak bypasses metering....so you get no fuel allocated for it.

On D-jet...a vacuum leak causes contraction of the barometric aneroid inside of teh MPS...causing enrichment.

So...a vacuum leak at idle rpm (when vacuum is at its highest) may not cause enough movement of the aneroid chambers to signal enrichment.....so it acts just like a vacuum leak causing lean condition ta idle....and normal or richer conditions at higher rpms.

A common issue is a vacuum leak that is juuuuuust large enough...to cause submarining idle speeds. On a 411/412 or type 3 with D-jet....this is actually characterized by a slowly increasing idle...say over 1-3 minutes and then an idle dip....that causes stalling or near stalling...until you rev it up or drive it some more.....and then at the next traffic light its idling near normal with a slow increase to say 1000-1200 rpm...then a stumbling dip again. This is usually because the baseline fuel mixture is just slightly too rich (ie: MPS settings or too high of fuel pressure)...and is be ing augmented by a small but badly located vacuum leak.

By badly located..I mean one that is close to the vacuum port for the MPS. A leak somewhere in the plenum.

OK. All of that being said....the first and primary part that messes this up...is that damn PCV valve. Get rid of it. Star with a 3mm orifice in the restriction.
Start with 30 psi of fuel pressure.
Adjust your valves carefully. Check them when hot. Make sure that none are overly large or small. Smaler than .002 is a problem. Larger than .003 is a problem.

Get a decent vacuum gauge. The deceleration valve should only be kicking in at MAXIMUM manifold vacuum and only at raised rpm.

Example: You usually pull about 10+ inches of vacuum at idle. Rev the car to about 3000...snap the throttle shut. Look at the gauge. The vacuum should spike to several inches higher than it is at idle....like maybe 15 inches of vacuum. This is where you want the deceleration valve to pop open.
It MUST NOT open at idle vacuum. It most be adjusted tight enough to never pop open below about 2300-2500 rpm.....or else it will be opening during warm up and cold weather at idle. The purpose of this device is to keep ultra high vacuum from damaging the MPS...and over-leaning at high rpm and high advance.

The stock injector seals are high rpm vacuum leaks waiting to happen. Change them out for CIS style "donut" seals. They are cheaper and fit tighter. See if you can get the brown or green viton ones used on early 80's Saab 900's with CIS.

The runner boots leak alot as well. Get new ones. Clean the runners so teh boots slide nicely. Smear the outside of the spigots on the plenum with high temp silicone (thin smear) like permatex copper, gray or black. Slide the biits onto the plenum spigots ...hard. Push Hard! Then while they are held against the plenum....clamp them on the runner side so they cannot slide back. The spigots on teh plenum are slightly conical so they expand the runner boots. The clamps keep them from sliding backward onto the runner. Once the silicone dries...they never leak.

If you have the combination vacuum advance/retard unit...you need to do this.

Once you have done everything else....set the timing as per the book (27 BTDC at 3500 rpm...hoses off). Then attach the hoses. You will immediately get crappy idle because the stock retard unit retards you down to only about 3* BTDC.
Turn off the engine. Pull the dizzy. Pull the advance unit.
Hook up a hand vacuum pump to retard side. You will notcie that the arm pulls back against a "pin" or stop that is anywahere from 5mm to 9mm in diameter.
If you have a nice fat pin....carefully drill a 2.5-3.0mm hole in it..and thread in a stop screw so you can make an adjustable stop to limit how far the vacuum retard draws the arm back. If its a small pin....too small to drill....make bushing with that you can modify by filing to make a hard stop. Do not use rubber hose or vinyl tubing for this busing. The presure from the vacuum and the hard arm cuts soft material in about a week. Use something hard.

You will also find that with the hoses on...it advances too far. On 411's and 914's there was an advance unit that has an outer stop screw from the factory. It had arm # 917. You can make you own stop screw with a short expanding panel bushing and a 3mm screw. Its carefull work...but works like a charm. THe expanding panel bushing should be no longer than about 5-6mm. So you will not have too many threads. Also the panel bushing should be aluminum and small bore because you can't use too much expansion pressure as the advance unit is thin walled.

The object to all of this is to get control of your vacuum signature and timing. Then we will properly adjust the TPS.

When all is said and done you should be able to moderate idle with about 3 total turns of the idle screw.

Invariably....when all of this is under control...you will also find that the MPS actually needs adjustment. The adjustment level of the fcatory MpS settings was actually quite crude because so many things were loosely controled. Ray