Rolling Your Own Gaskets

Yes. I am still working on Bopper trying to bring it back to life. The cylinder head is back on, and now I am trying to reassemble all the pieces to get her back on the road again.

A couple months ago, during disassembly, when I removed the carburetor from the intake manifold, I noticed the cork gaskets from the rubber bottom of the carburetor were horribly rotted and needed to be replaced. Now that I am back to putting it all back together, when I went to Murray's  to get the gaskets, but they didn't have any for this specific Toyota 3AC engine. However.... they had rolls of gasket material, so I thought, "hey what the hell, I'll just cut my own; that's what most gearhead folks do anywhere on odd cars when you can't really find readily available replacement gaskets from the store."

Note; To non-gearheads out there, a gasket is a piece of rubber, cardboard, or cork that goes between two metal parts to complete a seal. Getting two parts of metal to seat perfectly against each other is very difficult, and every modern car engine uses gasket material between two metal parts to fill in any irregularities, so that a fluid-tight and gas-tight seal can be formed.

But how do I make my own gasket? I recalled the woodblock techniques from my high school art class. Cover the metal part with paint, and stamp the pattern on a piece of paper.

Then tape the painted gasket picture on a piece of gasket material, and use a fine #11 edge blade (re: scalpel) to cut out the gasket pattern.

Below you can see the cut out paper pattern on top, the homemade gasket in the middle, and, below that, the piece of rubber the gasket will attach to.

You can see the new gasket placed on the intake manifold of the car.
And coated with a high temperature resistant silicone sealant.
The thick rubber block between the carburetor and intake is installed...
Another handmade gasket is put on top of that, with more high temp sealant...
and viola! 
The carburetor is installed! Now to hook up that mess of vacuum and fuel lines...

From Genes to Social Behavior - A Meme Gone Out of Control

Those close to me know about the recent fiasco regarding the neuroscience program forcing my colleagues and I to retract an abstract we sent to the Society for Neuroscience meeting this year.

The abstract, entitled,"From cell fate to human fate decisions: the role of notch signaling in global conflicts," was a satirical poke at contemporary neuroscience by claiming that all human wars are the result of one gene, Notch, which is required for nervous system development. 

The point of the abstract was to point out how easy it is to exaggerate the importance of single proteins and genes in the function of the human mind. True, Notch definitely is responsible for human wars (because we wouldn't have functional brains without it), but a lot of other genes and factors, to understate it, are required as well.

And, true to form, look what appeared in the November 7th issue of Science Magazine in a article entitled "Genes and Social Behavior." The figure that explains it all. We should all stop working; it's all figured out.

Head Gasket Finally Replaced

With a screw driver I was able to scrape off the carbon deposits on the valves in question (see previous post). Then, with a combination of steel brushes, more screwdrivers, rags, and engine cleaners, I tried my best to remove the gasket material from the bottom of the cylinder head. I couldn't make it completely clean, but I made it as smooth as I could, and with a straight edge the bottom of the head did not seem warped.

So, Bopper, what failed on you almost five months ago in Southern Ohio, with me since averaging probably 3-6 hours a week working on you in any time since I could spare, is finally being replaced. It's time for your new head gasket!

As you can see in the picture and video below, I had previously exposed and cleaned the engine block and cylinder heads. I was worried that maybe a piston component had failed, but it appears not so.

And the culprit! Compare the old gasket to the new one, and notice the rip in the gasket between the #1 and #2 cylinder hole. I had a brief moment of minor annoyance when I saw that the gaskets were not exactly the same, but the two coolant pathways on the front of the old gasket don't lead to anything, as there no passage way for those holes on the head! See picture at top of post. 

I bought some special gasket sealant spray from the auto parts store that contains bits of copper to improve heat transfer, which made the gasket a very pretty burnt orange look (Hook 'em Horns!). The gasket slipped right on the top of the engine block. Like a glove.

I took one last look at the cylinder and piston heads, said "It was good knowing you, but hopefully we don't have to meet again for a very long time." I put the cylinder head on carefully (it's a bit heavy!), put the 10 bolts in the slots, and tightened each one down in the correct order, carefully eventually torquing them up to 50 lbs in 10 lb steps.

Now I only have to install the carburetor, distributer, timing belts, water pump..... Twill still be a while before she's fired up again.

Valve Damage Question

This was an e-mail I sent to some of my gearhead friends today regarding the repair of my 1981 Toyota Tercel "Bopper":

Hi all,

I am finally putting Bopper back together and am almost ready to put the head back on the engine. Turning the head upside down to clean off all the old baked-on gasket material, I noticed one of the valves, third from right in attached picture (with a closer view in another picture) has some weird precipitate on it.

Since the old head gasket had failed and coolant was leaking into the cylinders, I am thinking that this is some weird antifreeze byproduct on the valve. It's very hard to get off.

I don't want to replace the valves, I want to finish this job and start driving Bopper again, but the question is, does this raise any alarm bells for y'all? I was just going to try to clean it as best I can and then put the head back on.  Have any of you seen this before?

Thanks,

Tim

And my mentor gearhead guru Mark's response: 

"It looks like carbon deposits to me.  As long as the valves are seating properly and there isn't carbon build up on the valve stem it should be fine.  The valve might run hotter than the others but that usually is only a problem on air cooled engines w/sodium valves.  Just make sure you scrape off as much of the old head gasket as possible and wipe down with acetone before putting the new gasket on.  And make sure the #1 piston is at TDC.  And follow the torque order..."

Thanks Mark! Anyone on the interwebs have any suggestion as well?

Pop Art Means Cutting Edge Neuroscience

In the latest issue of Science Magazine, a group of Israeli scientists recorded neurons of the hippocampus in humans with microelectrodes as part of  an epilepsy surgery. As the single neurons were recorded, the patients were played videos from various pop culture sources. After the movies were played, the subjects were then asked to recall what they saw. As you can see in the movie below, the sample neuron fires whenever Tom Cruise is shown, and, later, when the patient freely recalls what he saw on the TV, notice the neuron fires again approximately 1-2 seconds before the patient says "Tom Cruise." 

The video is amazing for its sheer pop art meets neuroscience combination. I thought it could be in a museum as an experimental modern art piece. But that aside, the big science ramification is that, perhaps, this neuron is where "the memory" of Tom Cruise resides. It also probably encodes more than Tom Cruise (as you can see in its sporadic response to other images), and whether it is truly where the memory trace exists can only be shown by either deactivating that neuron with GABA agonists / cooling, which is only done in animal models, or by stimulating that neuron and then asking if the patient immediately thinks of Tom Cruise. Even then, the neuron may still only be the "librarian" of the memory, and not the actual storage. Perhaps the brain doesn't make such distinctions in its storage mechanisms. 

These are tough problems to solve, but ultimately the most fascinating. I consider it even more interesting than the "C-word" problem. Oh brain oh brain, how ever do you store declarative memory?

Tour de Troit 2008

Last Saturday my friends and I went on a 42 mile bike ride through Detroit as part of an annual revitalization event. I had two bikes: I let my girlfriend take my mountain bike, and I rode in my folding bike. Folding bikes are not designed to go on long trips (they have small wheels and low gear ratios), but I felt I was in enough shape to handle the stairmaster that is the single speed. You have to pedal very very fast just to keep pace with the regular bikes.

The trip began at the old Michigan Central Station, a beautiful abandoned building that was in an odd part of town even when it was newly constructed. It will never be torn down and will forever remain perpetually mired in aborted renovation plans.

Not all the of the living things on the bicycles were human.

After a late start (10:30 AM) we were off, and we went directly towards downtown Detroit. You can see the route map and area highlight list below (courtesy of the Wheelhouse).

There were about 1100 bikers, but we were all appropriately spread out that only rarely did it become uncomfortably crowded.

In the video below, notice the iconic steam rising from the manhole covers as we pass Woodward avenue. If you look very closely as we make our left turn you can also see the Spirit of Detroit Statue.

 

After a brief tour of the downtown Detroit we then drove through the old neighborhoods on Detroit's Northwest side of town. There were only 2 other people with folding bikes out of the 1100 people, and people we would pass in the neighborhoods would always call out(especially the kids), "Whoah..that bike is cool! It looks like a scooter!" When Miss Trigger rode it, the effect was even more so.

In the final part of the trip, we headed south on grand river avenue for 10 miles back into corktown. I thought this was rather curious, but Miss Trigger told me the neighborhoods around that area are pretty bad. The police escort actually stopped the whole biking group two or three times on the road to keep us all clustered together. Whether that was to make the police force's job easier or keep us safe, or both, I don't know.

My favorite picture is the one below of Greg, happy and relaxed on a nice Saturday bike ride, with a wonderful view of an iconic image, unfortunately, of Detroit's negative population growth: the abandoned burned out building in the background.

The "bad ass" bike of the day award goes to the dude below. What is it even called?

The tour ended soon after that, and after packing the bikes up we had some lunch in Mexican town, drove back to Ann Arbor, and I promptly passed out for two hours. 

Continued Search for Optimal Rocket Motor #2

Who knew designing rocket motors from scratch would take so long? But..I finally think I am ready for a compression test next week with the full load cell test stand. I was originally using Elmer's Glue as a binder, but further tests revealed the Elmer's glue actually substantially inhibited the combustion and ignition (motors took forever to ignite, and then burn at a low rate for a minute or so...way too long when I want a burn of at max 2 seconds). I speculate that since Elmer's glue is water-based, it is somehow degrading the propellant.

I thus moved to an organic binder, a nasty smelling contact cement I bought at the local hardware store that is  used to apply linoleum to floors. The movie below shows a mixture of 25 g pyrodex, 3/4 ounce of the binder, and 10 g sodium bicarbonate (baking soda). After baking in the oven at 200 degrees for about a week, it was sufficiently dry to do a burn test. It took 5/6 of a second to burn (measured via the video time), which may be short enough to provide a good level of thrust for the rocket but long enough that the risk of overpressurization is low. Last night I gave myself a headache making some more motors (that binder glue is nasty), but stayed tuned for next week when fellow gearhead and garage guru Dr. Mark Lehmkuhle comes to Ann Arbor for a week! We'll finally get that static test up and running with the new motors!