Wagon progress update Part 2... the problems

[jlrftype7]

Congratulations!!!
_________________
'68 Westy- my first VW and vehicle/Bus- long gone.- sold it to a traveling Swiss couple....
'67 Type 3 Fastback, my 2nd car- gone
'69 Semi-Auto Stick Shift Beetle-gone
2017 MINI Coopers, our current DDs
‘84 Tin Top - Hilga....Auto

[kirk knighton]

Hi Bill - so is your beautiful golden 412 finally on the road?
Kirk

[Pepperbilly]

Hi Kirk,

Yes she is on nice days and runs beautifully. I had to install 4 new fuel injectors and solve some fuel tank issues. After that I was home free! Little problems here and there but they are being solved as days go by. I could not be happier!

Hope you are doing well,
Bill

[kirk knighton]

Hi Bill, doing okay, and I'm glad to hear your long restoration job is complete. Another 412 on the road is always a good thing!

Do you remember my grounding problem on my other 412? Any chance I could drive down there ( once the roads clear ) and we could put it up on your lift and have a look at what might be the problem?

Kirk

[Pepperbilly]

Just doing my first break-in oil change. After a close inspection I have found only 1 oil leak. The Taco plate leaks. It had the new o ring (the orange one). I pulled the plate down and found traces of case sealer used on the ring and housing. Hmm…

I have a new o ring, the same one. After I clean everything off I want to reinstall correctly. Is it advisable to use any type sealer on this o ring and seat? I want to get it right the first time because draining the oil multiple times is not fun. The really good news is nothing else in the entire drive train is leaking!

Bill

[CAVEHEAD]

What's the "Taco Plate"

[Pepperbilly]

[raygreenwood]

The problem that causes this leak is ....usually....that the "taco plate" itself is "dished" or bent.

In a perfect world, the plate is perfectly flat so that when you bolt it down to the case, the flange/ledge around the edge of the plate compresses the o-ring against the case like this:

But when the plate has been pried on or the bolts heavily over tightened etc....the malleable mild steel of the plate gets a very subtle dish shape...downward away from the case...letting pressure off the seal like this:

So your options are to either dish the plate back downward very slightly....a trial and error pain in the ass.....or if the case is disassembled you can lap, file or mill the center area where the bolt holes are a bit to allow the plate to sit closer to the ledge and compress the o-ring more.

The problem is that the plate is roughly the same kind of soft steel as the engine sheet metal. Once you starting bending it it gets easier to bend.

So...when the plate has enough flatness to compress the seal...what it looks like from the bottom is that when you put the plate into place...and look upward through the bolt holes in the plate....there should be about a 1/16" gap between the plate and the threaded bar of the case.

As you tighten the two 6mm bolts....it should put tension on the plate as it draws it toward the engine case. This is what actually bends the plate in the long run. Over time with heat cycling it fatigues and takes on this dished shape so it no longer seals. This is why you have to re-bend it flat.

You might also check this out. Pricey but already has the hole for a temp sender
https://lnengineering.com/type-4-billet-sender-plate.html

Here is the factory version with boss for sending unit
http://www.autoatlanta.com/Porsche-914-Taco-Plate-srch.html

More

https://914werke.com/shop/ols/products/oil-temperature-assembly

This guy makes nice ones. He is listed all the time in 914 world

https://www.thesamba.com/vw/classifieds/detail.php?id=1251577

Ray

[Pepperbilly]

Thanks Ray!

I checked mine out yesterday and it appeared nice and flat… I will check it more closely today.

So in a perfect world that plate and o-ring should not need any type of sealer? I can see that…

Thanks for the alternatives you presented. I will consider all options.

Bill

[raygreenwood]

[Pepperbilly]

Checked mine again and it is very true. Now, when I first removed the plate I found uneven application of what appeared black RTV sealant everywhere… on the case, on the o-ring and on the plate. I had to clean all this off. This could have been the issue. I’m gonna go ahead and use a new o-ring and put it back together without any sealant.

Bill

[raygreenwood]

[Pepperbilly]

Taco Plate Update:

Got mine back together and so far after running the engine for about an hour I have no leaks.

My plate checked out fine. I installed a brand new o-ring. This was my method...
1st Set the ring into the case seat.
2nd Apply just a smear of engine oil on the plate seat for the o-ring.
3rd Carefully slip the plate into the already seated o-ring trying to get the alignment close on the bolt holes.
4th Wiggle and rotate to align the plate with the holes. Confirm a nice snug and positive fit.
5th Install the bolts and tighten evenly.


The old seal with improper sealant and not even. No wonder it leaked!

Bill

[Pepperbilly]

First of all I would like to know if originally on a ‘73 how the dome light is activated. Actually, do both doors on a wagon activate the light or is it just the driver’s door?

My dome light quit coming on when opening the door/doors. It would work in the manual on position. Pulled both door switches and found a bad wire connection on the driver’s side. Repaired that and the light is again activated but only by the driver’s door. Passenger door does nothing. Of course I paid attention to the current flow diagrams, but still not sure the job of the passenger door. My car has the seat belts no longer connected to interlock and I have also pulled the warning buzzer relay. Always hated that noise.

Bill

[raygreenwood]

It should be activated by either door. But, the switches are different.

The drivers door has the four pin switch (either 3 or 4 have to check). The passenger has a single wire switch if memory serves.

Both switches simply supply ground when the door is open. So the passenger side switch should have a single wire... .but if the switch body itself is corroded and not grounded that can cause this.

Or if the ground wire is broken someplace in between. Ray

[Pepperbilly]

Yes Ray... the driver's side is a 4 prong switch. This one does not ground to the body via the sheet metal screw, it grounds thru the wires only. The switch is fine because I cleaned it and checked with an ohm meter. The passenger side is a simple 1 wire grounding switch and it grounds thru the sheet metal screw. It too works fine. So somewhere the wire from the passenger side switch is not making it to the driver's side. Not sure if I have complicated things by not having the seat belts and ignition buzzer relay pulled out of the circuit? The wire from the pass switch is brown/white striped and is there running under the dash. Looks like it may be disconnected or broken along the way. SO, you are right...both doors should activate the dome light.

Bill

[CAVEHEAD]

[KTPhil]

I have not been able to find the 4-pole (driver) door switches for the Type 3, which I assume are used across the product line. However, I am not using the door/ignition key buzzer wire ('71 Type 3), so I replaced it with a passenger 2-pole, and taped up the wires (after also disconnecting them at the other ends). Maybe you can do the same?

[Pepperbilly]

[Pepperbilly]

Hey everyone,

Will add things from time to time about problems that come up.

Just a beautiful fall day yesterday to take Goldie out for some exercise. Mid 30s outside so its a cold weather drive.

She starts right up and turn on the gas heater for warmth. Goes through it’s idle warmup smoothly for a few minutes with no problem, just like it should. I am backing out of the garage and stalls out in the driveway. I try to restart but the engine is now running very rough and stalls again. Ok WTF! It now will not restart but cranks ok. I walk away and come back in 20 minutes and she fires right up. Runs smoothly for about a minute and stumbles and dies again. No restart. It repeated this behavior in another 20 mins. Ok, where’s the problem?

I spent the rest of the afternoon checking basics. The spark plugs were black and sooty. I installed a new set because I did not want to clean the old ones. Vacuum tested the MPS and it holds vac. Checked the cylinder head temp sensor at different temps and it passed. Distributor dwell was at 49 degrees running, check. Replaced the fuel filter again because it had a bit of that brown silty material in it…but really not much. I will have to keep doing this until my gas tank completly settles out.

Well, about 6 in the afternoon I tried a start. She fired right up! The idle settled in and my fuel pressure gauge showed 28psi…perfect. Now the discovery. Engine running sweetly I started to jiggle FI wires. When I touched the cyl. head sensor wire at the connector the engine immediately stalled! Restarted the engine and ran perfectly until I moved the wire again. Stalls out again. Needless to say the previous repair I made to this connector is not good. Will repair this in a few days when the weather is a bit warmer.

Hope this helps someone in the future when you encounter these weird problems. I have to really be careful because I am still running my original FI harness. Maybe someday a new harness will be needed. I am just thankful this happened in my driveway!

Bill