Fitting a stock air cleaner on a Weber 32/36 - a few ?s

['76mintgrün'02]

When I switched distributors, not too long ago, the new curve eliminated the lugging ping and created an exhaust note I had not heard before.  It is a very clear tone at the tailpipe, when I stomp on the gas.  Well, it went away, when I removed the lid I'd beat the dome into, so I figured the much flatter '76 lid must be the reason and decided to add some shape to it as well.

 

The clay ball test said I had 9/16" of an inch clearance to the hood, at the center of the lid and measuring the height inside the lid, next to the breather tube showed that it was not much taller than that little tube.  The tall roundel looks nice, but in a situation where space is limited, it is not very practical.  After a LOT of massaging yesterday, the roundel is only 1/16" closer to the hood, but the inside dimension grew by about 1/2" and the happy tailpipe sound returned : )  (whew)

 

You can see the difference by comparing this photo to the one above.

I am learning that my potter's wheel is useful for more than just clay and have to say that every time I use that tool, it makes me happy.  I made a little contraption, to roll some dome into my lid and it wOrked!

( I was considering dropping the shot put onto my lid, with a sand bag for padding, using that big brake drum for support, but this tool gave me a bit more control).

 

I made a ring of plywood, to fit the flat part, that sits on the filter itself

and added two sided tape to help grip the lid, along with four little keepers at the corners.

The strips of cardboard in the lid's ribs made it a smoother rolling surface and kept the ribs intact. (self portrait)

The lid frame is attached to a "bat" that is aligned to the wheel with two little pins.  (this allows pots (or tools!) to be removed and reinstalled on the wheel)

The 3/4" ring of plywood was supposed to allow the 1/4" of height I figured I'd add, but I could not get it to go that deep, so I added some dish to it.  

Then some more dish...

Eventually, I just cut the whole bottom out of the fixture.  (action shot)

Here is the lid... I think it is finally done.  (aside from getting a second coat of matte black paint today).

(before)

(after)

These pieces of clay show the outside and inside clearance.  

There is still half an inch of space between the center of the lid and the hood, with a good half an inch mOre clearance inside, where the air climbs up over the hump, to get sucked down into the carb.  I was very pleased to hear the difference this made at the tailpipe.  The poor thing was suffocating, with such a flat lid.

 

It will be interesting to see if the tool will roll the early style lid back dOwn in the middle.

 

I took a few videos of the contraption in action and will try and get one or two up on youtube, just for fun.  

Tom

 

Edited June 12, 2017 by '76mintgrun'02

[Stevenc22]

Everything you do is so well documented and beyond ingenious. I do wonder how adding dome to the lid helps air flow since the dome is post filter, aren't you still limited by how much air comes in through the snorkel and through the filter? Unless you think you have some weird vortex being created in the center and the dome is helping to smooth air flow.

['76mintgrün'02]

Thank you Steven.  It takes a bit of faith to fumble into these weird ideas and it was a relief to have this one work so well in the end.  I don't think there is anything weird about the 'vortex in the center', but I do believe the dome is allowing better airflow.  I can HEAR the difference and feel it as well.

 

The filter adds some resistance, but I don't think it is much, as long as it is clean.  The size of the filter inlet at the snorkel is another limiting factor, I suppose, but again, not too restrictive.  I believe all of these things are cumulative and opening up the clearance just before the carburetor has made it run much better.

 

One fun thing about this setup is that I could bolt it right onto your car, so you could try it and see... if you hadn't recently gone to side drafts and lived a little closer, that is.

 

I did test fit my early style domed lid on Nathan's 38-38 and it was too tall.  I think this one will fit just fine and am hoping he will be a guinea pig and try running it, for comparison's sake.  A larger carburetor should be even more appreciative of the increased airflow.

 

I wish I had a pile of lids here to play with!  I like my new tool.

 

Here is the first video.  The second one is longer and still uploading.  

 

 

 

 

['76mintgrün'02]

As a machinist, it drives me a little nuts to have it spinning out of round, but forward momentum was required.  

As a potter, helps if I think of the irregular shapes of some Japanese pOttery.  

This lid is mOving in a spiral.  It will help with airflOw.

 

I wasn't sure I should give the project the couple of hours I thought it'd take, when I started at ten in the morning.
Thirteen hours later I went for the test drive.  I did take a little nAp, but skipped supper.  Having too much fun.

 

It is easy to highlight the glOry, using photos to frame the highlights, in favorable lighting, with very basic photo editing right at hand.  Turn down the highlights, bump up the saturation.  straighten and crop if needed.  

 

Documentation is getting to be half of the fun.  Sharing it is the other half.  (It is quiet here).

Driving and having things be perceptively better is the mOst gratifying part.  As in, I feel grAteful.

 

I gave the dome another coat of Blue Coral, followed by Macgyver's Gold wAx.

as well as the lid.  Sso it'ss Sslippery Ssmoothe insside.

 

 After another twelve hours working on my intake, I think it is almost done for now.

 

I still need to fill the snorkel with drinking straws.  (I will shoot some sillycone through them beforehand).

I still want to make an aluminium insert, to sm00th the Weber's center web's edges.

I  still need to give the lid one more coat of paint.

 

The matte black paint on the lid has dried to be very tough.  That whole process did not put a scratch in it.  

I goofed it up rubbing on it, once it was in the car, so I will coat it again.  

 

It only has one coat of Krylon on top of the primer.  

I think the durability is due to the bOnd, 

thanks to the sandblasted/handsanded/acidwashed/primered surface.

Back on the potter's wheel for a respray, after a light hand sanding.

 

I am almost done.  Almost done.

 

 

[RAS-2002]

Tom,

Your talents are so far beyond amazing, they're ... they're... amazing!

-Bob

['76mintgrün'02]

Thank you Bob : )

Sometimes I feel smart, sometimes not so much so.

I just added the tag I cut off of the new mower bag, since I stuck a couple of knuckles into the bite.  

Those little oak blocks have sharp edges.

 

The 76 lid developed a little crack above the B, so I smeared some JB on the underside to keep oil from weeping through.

Yesterday, I hammered the power dome back down in the middle.  I like the shape better now and it has about a quarter of an inch to the hood, which seems like just enough.  It is good that my engine mounts are not squishy, or I'd need more clearance.

 

The early lid required modification of the clamping blocks and the notches got into the screws, so little chunks of rubber hose were added.

Mounting the lid right side up also called for different blocks, along with washers and some more bits of hose for grip.

 

I compared the height of my 76 lid and the stock early lid and they are very similar now.  The 76 has a bit more dome around the middle, but the middle height is about the same.  The problem with my 76 lid was that someone had beat it down for clearance.  If I find a nicer  example at a good price, I will purchase it and puff it up as well.  The center emblem looks really nice, when it has not been rubbing on a hood.  

 

This one looks better than it did when I got it.  I can see why it cracked where it did.

 

['76mintgrün'02]

There was a recent thread about aftermarket filter assemblies, in which there was a discussion about after market intake manifolds not having the provision for a stock filter mounting bracket on the driver's side.  That discussion prompted making this bracket as a possible replacement.

I have a spare head/intake/carb on the bench, so I made a paper pattern and traced the stock bracket on the back side.  

Then cut that out of stainless steel.  (I got a little lazy and simplified the shape, from the original pattern I made.  It'd look cooler, if it was cut out like it is on the paper).

It uses two of the carburetor mounting studs, instead of bolting to the end of the manifold.

The bending process is a little bit fussy, to get it to line up at the top.  I tested the fit on my engine and it seems pretty close to the original.  

 

If you were to do it this way, you would want to use a paper thin carb base gasket, so you can cinch the bracket down, without distorting the base of the carburetor.

 

The original design seems superior, but on some manifolds that may not be 'practical'.

Here's one more look at the two examples (because photos are fun).

['76mintgrün'02]

Same song, second verse...

3/8" to top of cut-off disc

Just enough disc left to finish the cut  

Set height for second cut

 

Removed 'extra' to fit it inside

Ready to TIG-tack in place (NOTE-- this arrangement did not fit well, due to a lack of clearance between lips-- see below)

Stock rubber seal cut (with plywood inside)

 

This installation will use the Weber adapter

(this is the style I have) 

This is the difference in bracket alignment, between the two adapters

(I bent this bracket around to fit mine, so it's no longer stock;  but still, this difference surprised me)

 

Height wise, the Weber adapter is .1" taller than mine (base to shoulder, below the top lip). 

 

With the trimmed air cleaner housing's bottom flange, the lip was a little too tall, so I trimmed 1/16" off the top of this lip, so the seal sits down on the shoulder.  I also thinned it and smoothed it out a little bit.

 

The clay ball on a stock lid measured 5/8" clearance to the underside of the hood with this setup.

 

Height is not an issue on my current setup, but I see evidence of contact between the hood support that runs lengthwise and the driver's side of the housing.  My engine mounts might be getting a little soft.... or something.

 

 

The hood has blown down in the wind a couple of times and it possibly flexed when it landed.

 

Edited May 15, 2018 by '76mintgrun'02

['76mintgrün'02]

It turns out that putting the cut off flange on the inside of the remaining flange did not leave enough room for the seal and the adapter's lip, so I decided to make another stainless steel flange like the one on my car now.

 

I skinnied up the plywood form to 3/8" thick and cut a 9/16" wide strip of stainless (which should have only been 1/2" ). 

The length of that piece is around 11 1/12", cut to fit the form and welded at the seam.

Screwing the form to a piece of plywood worked pretty well for the hammering, but this could probably just be done on the bench.

Once again there was too much meat on the lip, so I trimmed it.

 A drum sander did a much better job than this stone.

I took a small amount of material off the outside of this lip, using the drum sander.

the pieces fit together well now, I think.

It was a mistake to shorten the lip on that other adapter, (in an attempt at fitting it into the previous flange arrangement), so I freshened up another one I had on hand.  Overall it is in good shape, but the edges were a little gnackered up, so I smoothed them down. 

 

 

Tomorrow I will test these parts under my hood and might roll some shape into the lid with the potter's wheel.  I will be sure to take some pictures  

Tom

['76mintgrün'02]

The clay ball height check indicated 1 cm between the air cleaner lid and the hood.  I am going to call that good.

 

The other '76 lid got some more attention today.  It feels like it has come a long way.

 

 

 

 Tons of tiny taps put some puff in the logo and a bunch more erased the other dents and dings.

 

 

 

 

Well, all that fun happened a month ago, but today I got to play on the potter's wheel.  

 

I am happy with how it turned out.  I wasn't going for the 'about to pop' look, like the one on my car now, but just wanted it to look like it was holding a breath.  (I heard a potter describe a pot that way once, he actually blew shape into a vase he'd made, to demonstrate)  The light in this photo makes it look taller than it is.

That was after some final sanding, before painting

The filter base has been prepped for blasting.  I will just be stripping the outside, so I made some wooden plugs to keep the sand out... but did not get to it today.

 

 

[7502]

That is a thing of beauty. 

Although the BMW logo is askew!

['76mintgrün'02]

...Intentionally askew, I do believe!

See how the M lands right bet-W-een the ribs?

I think that that was on purpose.

Perhaps the stamper was feeling rebellious .

It now appears there were two styles of lids, Cross-Hair:

 

and Iron-Cross:

 

I·ron Cross

ˈī(ə)rn ˌkräs/

noun

 

1. the highest German military decoration for bravery, instituted in 1813.

Edited April 30, 2018 by '76mintgrun'02

['76mintgrün'02]

I got a coat of paint on the body of the air cleaner today, after a bit of blasting.

 

 

 

 

 

Made a cardboard shield, to mask off the inside of the body.  14 7/16" fwiw.

 

Robbed one cutter off of this tool, to make a slightly longer version.

 

 

I cut out a piece of plywood, to attach to a lazy Susan, to support the parts during the painting process... and stuff.

 

And inserted this cardboard ring in the lip of the lid, to keep paint off the top, while doing the underside.

Then decided there was eleven times too much texture in the paint I applied yesterday and spent a bit of time wet sanding it back to smooth.  The lazy Susan was very very helpful for that process.

 

 

that picture looks like there is no paint, for some reason; but I am happy to say, I did not sand through the paint.  It is way too pretty to be hiding under orange peel.  I think I'll try satin black for the next coat.

 

so, that's that.

[Simeon]

Why were you so keen not to blast the inside? It’s not so complex a shape that you couldn’t adequately clean it afterwards. 

['76mintgrün'02]

I guess I like the original color and the paint is in good enough condition that I may just leave it.

If I do decide to paint it, a light scuffing seems like it would be sufficient preparation.

There is no corrosion in there.

 

The outside, on the other hand, had quite a bit of rusty pitting and blasting seems like a very effective way of getting rid of it; as well as getting into all those hard to reach areas.

 

I did not have strong feelings about it and I agree that cleanup would not be difficult.

(the cardboard disc is for painting prep, not part of the protection from sand intrusion).