Repairing Engine Tin, A newbie's lesson in welding - second side Options

[Superhawk996]

Like this one?
BTW I have the other side as well but it lost its label.

@Jett

Wow - I've never seen NOS tin. Really interesting to see what they looked like originally.

@Jett ,

@superhawk996 looks like yours are not far off (IMG:style_emoticons/default/smile.gif)

Yeah but why stop at good enough. (IMG:style_emoticons/default/laugh.gif)

[VaccaRabite]

What I want to know is - what on earth caused those cracks to form in the tins in the first place. That would seem to be a weird place for the tins to work harden and crack up.

Zach

[Superhawk996]

What I want to know is - what on earth caused those cracks to form in the tins in the first place. That would seem to be a weird place for the tins to work harden and crack up.

Zach

A big part of it is the quality of the stampings which as Mark states is poor. There is a lot of draw to these parts which thins the metal as it is formed. The metal is only like .037" or so to start with.

Then you put a coil on there with a particualar type of braket (the dog leg version with the snubber) and it stressed the metal and causes local cracking. After it has cracked, over time it will propagage widlly along the stress lines internal to the stamping.

[Mark Henry]

What I want to know is - what on earth caused those cracks to form in the tins in the first place. That would seem to be a weird place for the tins to work harden and crack up.

Zach

The coil mount area?
It's the engine rocking and vibrating, bending the area till it fails.
It really is huge forces at work here and another example that Porsche/VW never expected these cars to be still around 50 years later.

[Jett]

Like this one?
BTW I have the other side as well but it lost its label.

@Jett

Wow - I've never seen NOS tin. Really interesting to see what they looked like originally.

@Jett ,

@superhawk996 looks like yours are not far off (IMG:style_emoticons/default/smile.gif)

Yeah but why stop at good enough. (IMG:style_emoticons/default/laugh.gif)

@Superhawk996 (IMG:style_emoticons/default/smile.gif) High standards and strong bias for action... we like your style!

[seanpaulmc]

Hello Mark Henry -

Could you scoot that tin around and show the back inside corner? Mine looks to have been modified but cannot tell for certain. I don't know what it should look like.

Also, does the front outside corner have a captured nut welded on the tin or is it just a straight thru hole?

the passenger side 2.0 engine cylinder cover is impossibly hard to find as many have been cut (as yours has) for air conditioning. I applaud you in your job to fix this piece. HOWEVER when it gets this bad, could be easier to convert a 1.7 1.8 piece (readily available) by relocating the two spark plug holes. We are in the process of recreating the right front piece where the accelerator cable passes through. THIS piece is IMPOSSIBLE to find

Like this one?
BTW I have the other side as well but it lost its label.

[914sgofast2]

What I want to know is - what on earth caused those cracks to form in the tins in the first place. That would seem to be a weird place for the tins to work harden and crack up.

Zach

The coil mount area?
It's the engine rocking and vibrating, bending the area till it fails.
It really is huge forces at work here and another example that Porsche/VW never expected these cars to be still around 50 years later.

The coil should be mounted on the fan housing, as well done on the VW Bay Window buses. Post a WTB in the Samba website classifieds for a Bay Window coil mounting bracket and save your tins from cracking in that area again.

[Bleyseng]

the passenger side 2.0 engine cylinder cover is impossibly hard to find as many have been cut (as yours has) for air conditioning. I applaud you in your job to fix this piece. HOWEVER when it gets this bad, could be easier to convert a 1.7 1.8 piece (readily available) by relocating the two spark plug holes. We are in the process of recreating the right front piece where the accelerator cable passes through. THIS piece is IMPOSSIBLE to find

Like this one?
BTW I have the other side as well but it lost its label.

Gotta kind of wonder if the old tooling for this is lying around the basement at the Karmen factory somewhere, or if it got melted down for some rebar in China.

All the engines were made and assembled in the VW engine plant. They just had one day scheduled to do the 914 engines on the line. All the tin and parts were made by VW

[Mark Henry]

Hello Mark Henry -

Could you scoot that tin around and show the back inside corner? Mine looks to have been modified but cannot tell for certain. I don't know what it should look like.

Also, does the front outside corner have a captured nut welded on the tin or is it just a straight thru hole?

The circled hole has a M6 weldnut.
Not sure where you mean, can you circle the area you want me to take a pic?

[Shivers]

The dies used to pop these pieces out were quite crude.

That is an understatement.

I had always assumed some of the distortions I've seen in tin were from rough handling and/or engine drops where the tin snagged on the seals.

I never thought about it before but that right front corner piece that is spot welded on looks like it would be pretty easy to reproduce and would make patching tins butchered for AC easier.

That sure would be nice! It is a lot of work to fabricate from scratch and then you are constantly fighting with distortion induced by the welding repair.

I use my air compressor with an air nozzle to cool the metal after each tack when I do sheet metal. Keeps down any distortion, and I do not have to wait as long between.

[ClayPerrine]

Take a section of copper sheet or copper pipe and beat it flat, then back up the weld area with the copper. You still have to spot weld, but the copper backer stops it from blowing through and doesn't stick to the weld.

Great advice!

Thanks (IMG:style_emoticons/default/smile.gif)
Thicker copper sheet holds up better but beating copper pipe flat is handy for backing up curved shapes and hàrd to get to areas. The copper has to be pressed against the weld area, if there's a gap it will blow through. The pipe is too thin of a material and will degrade quickly, but I just make another tool.

I have a number of old server CPU heat sinks that are about 1/4 inch thick pure copper with big fins on them. I took them and made some various rounded bits from them. They work great for backing up welding when you don't want it to blow through.

[seanpaulmc]

The area of concern I have for this piece of tin is circled here.
On mine it looks and feels like it has been trimmed, but I don't have anything to compare it too. I can't tell if this was just a little snip to make it fit or something more.



I appreciate all the tips on welding. I've gotten some 1/8" thick copper flat stock. I've made a few weld backers of different sizes. And, I'm using some copper pipe for the curved areas. It's certainly helped!

New question:
How many tins are there for the 2.0 L engine? This is a '73 if that matters.

Thanks!

[Mark Henry]

The tin is correct in that area, you're good to go.

[wonkipop]

mate
you are a hero for working out how to do this.
fortunately i do not own one with a coil screwed down on the tins.
which german kook thought that was a good idea?
and those guys are the masters of metal?
(you know the germans have some kind of perverse respect for the brits?)
the japs would never have made that mistake.
thousands of years making swords.

but good old american know how to sort it.
(mind you same know how also screwed the cars, but would be the same here).

(IMG:style_emoticons/default/beerchug.gif)

[930cabman]

mate
you are a hero for working out how to do this.
fortunately i do not own one with a coil screwed down on the tins.
which german kook thought that was a good idea?
and those guys are the masters of metal?
(you know the germans have some kind of perverse respect for the brits?)
the japs would never have made that mistake.
thousands of years making swords.

but good old american know how to sort it.
(mind you same know how also screwed the cars, but would be the same here).

(IMG:style_emoticons/default/beerchug.gif)

Perhaps $$ caused some German engineer attached the coil to tin. Don't forget, it has worked for many years

Someone needs to gear up and get us new engine tin

[seanpaulmc]

Finally got back to finishing up the tin repair.
Another tin saved, sort of. At least it is better than what I started with and can now be used.

I chased all the cracks to ends.
I welded in patches for the two torn out holes.
I filled all the pin holes (held up to the light to find).
I'm not grinding down further to leave strength in the welded areas and remind me of this when I look back on it in the future.
Best part is I'm learning to weld - first part ever welded.

I appreciate all the advise provided. It's helped a ton. Using a copper weld backer has been crucial to working on the thin metal of the tin. Because of the complex shapes of the tin and where the cracks were I had to make a copper thimble to hold in place while making a spot weld. Worked pretty good. So, here's the pictures...

[seanpaulmc]

When taking the Tin off the engine, I have this small piece on the 3/4 side at the back part of the head. The leading part of the head is where the oil cooler is. Not a very good picture.




I think this is part 20 in the PET - 022 119 361, air duct /H/R.

Of course this part is missing on the left side of my engine.
I think I need part 21 in the diagram which for the 2.0L is 039 119 362, air duct /H/L.

Would someone confirm the P/N for me?
WTB this part if anyone has extras?

Thanks

[seanpaulmc]

Are the heat control boxes salvageable?




Thanks,

Sean

[Mark Henry]

Are the heat control boxes salvageable?




Thanks,

Sean

No they look way too crunchy.
The rest of your work looks good (IMG:style_emoticons/default/thumb3d.gif)

[930cabman]

Great job, can I send a couple of mine in for repair?