78 Spitfire project

[400brian]

A couple little details were crossed off the list today.

The NOS tool box door was the newer variant, the one with a latch. There is nothing in this tank to latch to, so I found some plastic hole plugs on Amazon that filled the hole well.

I will have to paint the door to get a perfect match with the tank. Haven't decided yet.

Amazon also supplied some steel hole plugs to fill the missing one that covers the secondary bolt access hole. Plan to paint that one green.

[400brian]

On Wednesday the Grandson came out, and we got to work.

We began by installing the plastic hood guides that are pop riveted to the pan inside the bumper at the rear of the hood. Because these are plastic, the 3/16" steel pop rivets are installed with a steel backer ( think tiny washer ). The guides were NOS, and it is possible they have contracted a bit over the last 50 years. The holes lined up with the ones in the pan, but the guide didn't really lay flat on top of the pan flange where the hood is going to sit.

With a guide installed on each side, we went to work on the bumper. The guides have to go on first as the rivets will be covered by the bumper.
We wired the bumper up at the rear, then popped a couple rivets in one of the front brackets. There are two attachment points on the side of the pan, each using one 1 3/16" long x 3/16" black anodized rivet. These are the longest pop rivets I have ever worked with. There is a nylon standoff that goes between the pan and the bumper. The rivet goes through the bumper, through the stand off, and the pan, where a backer is placed on the rivet before pulling it.

Everything lined up well, and we soon had the four rivets on the sides pulled, as well as the four short rivets across the front. As I admired our handiwork, I realized I had forgotten something. The outer flange of the hood guide should have been slid inside of the upper flange of the bumper.
Not being inside the bumper, it was going to catch the bottom of the hood and cause problems. The only fix was to remove the two rear rivets and do it right. We are used to doing everything twice, but I really didn't want to do this because I only had one more of the long rivets.

Nevertheless, I drilled the rivets out, I fought the flanges into the bumper, then had to fight the stand offs into the bumper from the rear. It took a bit of tweaking, and I did get them in place. I installed the spare rivet, and we will have to wait until another gets here to finish the job. I had been looking forward to putting the bumper stripe on, but decided to hold off until the last rivet is in.

I asked Galen how he felt about doing a test start of the engine? Which he agreed sounded like a great plan. I mixed some oil heavy premix in a squirt bottle, Shot some in the carb, and pulled for effect! Expecting the Kohler to pop right off, I was a bit let down when absolutely nothing of the sort happened.

I took the fuel line off the pump and ran some gas into the carb bowl and tried again...with the same lack of results. Now the compression on this thing is fairly stout, and I am pulling with my left arm not that it matters much. I am reminded why I have e-start on all my sleds. We pull the spark plugs and again confirm we have spark, and I note the plugs are quite dry. To remedy that, I shoot some gas down each hole. I am now confident it will bark on the next pull...it does not.

OK, my arm hurts and my better judgement is telling me to figure this out. I decide to confirm that the carb screws are set to the book settings. I find that the slide is closed, so I open it the 2 turns the book recommends. I then set the air screw to the 2 1/2 turns recommended. I shoot a bit more gas down the plug holes, making sure we have it flooded now! I begin pulling, and with a few pulls the engine sounds and feels different, it is coming alive! Another pull gets us a bark, and a couple more has it running!

I have a video of it running on my FB page. We have more work to do, and you can't really tune a snowmobile engine at 75 degrees, but we heard it run! This was Galen's first engine start up, I hope he remembers the experience.

[400brian]

I shot some Krylon Fusion on the tool box door and the re-worked bar pad today.

And in preparation of painting the tunnel, I drilled the Deere recommended hole location for the bar warmer switch, and cleaned the oil residue off the tunnel sides.

[400brian]

Too hot to be really gung-ho about anything today. But we did shoot some Blitz Black on the clutch / belt guard.

We also put a new bumper stripe on. The tape was NOS, so probably close to 50 years old. The problem I have seen with the NOS decals and such is the protective paper is very hard to get off. Same with the 1/2" tape. We practiced on a piece we stuck on a paint can, and it was a challenge.

I left a tag end on both ends of the bumper so we had a sacrificial piece to get started on. I worked on one side, and Galen the other, using a hobby knife to try and split the reflective tape from the paper cover. Just a bit of a corner didn't work, you needed to get the whole thing started. I finally succeeded, and carefully pulled the cover tape off in one piece!

It was a good day!

[400brian]

I think the tank is outwardly finished. We started on this back in April I think. The original tool box door was badly broken. I had an NOS door I had bought years ago off eBay, but it was really for the later models. I had put a plastic plug in the latch hole, and thought that was all it needed. On a trial fit of the door, I found it wouldn't fit properly in the opening.

My best guess was that I needed to move the hinge back 1/8" to 3/16" to allow the door to drop into the opening. I made a shim out of 1/8" thick black plastic the width of the hinge, and drilled the three holes in it. On the next trial fit I found I found I was close.

I had made a couple of aluminum shims from 1/32" sheet just in case the door didn't fit square, so I installed one at the left side fastener because the left side was fitting tighter than the right.

That pretty much cured the problem. I guess the only thing left is to install a fuel pick up in the tank.

[400brian]

Today we worked on a number of details. The painted custom bar pad was installed for what I hope is the last time. The acoustic attenuators were installed on the heads, and we assembled the fuel pick up on the rubber bung and fought it into the tank. The only other sled I have had to use this push-in system on was a 340/S.

We also painted the bumper rivets Blitz Black, and we covered the red RTV that oozed out of the exhaust joints with the same stove black paint we did the muffler and pipe with.

Earlier in the week we had painted the clutch guard, today the tape was removed that had masked the decals on it.

It was a good day!

[400brian]

Preparing to paint the tunnel.

Looking at various photos I have posted, the front bulkhead behind the hood hinge has needed cleaning for a while, finally did that.

There was a steel hole plug in the tunnel bulkhead for the J-clamp that retains the speedo cable. If I hadn't read about this in the speedo installation instructions, I might never have noticed. Galen reached in and installed and held the bolt, and I tightened down the nut.

We have selected a taillight, and refinishing is ongoing along with some other small parts.

[400brian]

The taillight housing we picked out to use on the Spitfire was painted in the last week, and today I showed the grandson how to clean the electrical contacts in the housing and a bulb we had on hand with a bit of 400 grit.

We then connected the wires to a 12 volt battery to confirm the assembly was ready for a future installation.

[SS440-80]

Keep up the good work, it will be amazing

[400brian]

The grandson was out Wednesday and we shot what I hope is the last coat of Emerald Green on the tunnel.

We had originally shot it on July 18th, but while we were doing it he said to me; this is not turning out well, and it was not. The cause of that was no doubt my fault, we were pushing to get the painting done. As soon as the grandson is in the garage he has the spray can in his hand impatiently pacing around eager to pull the trigger. I am trying to impart patience on him, but eleven year old's have that in short supply. Now he knows what happens if you paint before it is ready to do so.

We should have sanded the self etching primer that I had applied, smooth. But in the rush to paint, that got omitted, and as soon as the gloss paint hit the surface it was apparent, it looked like the primer was mixed with sand. I color sanded the tunnel last night with 400 grit and got things smoothed up, wiped it down with a rag with some thinner in it, then blew the whole thing off with air. We shot it again today, and it certainly went much better. He pronounced it good, and being as this is a rider, I don't think we should let perfection destroy good.

He wants to display this sled at a show the later part of August, so we need the tunnel wrapped up as we still have some work to do on the hood.

[400brian]

A day later I took a look at the tunnel and decided I could live with what we now had. No reason to allow perfection to be the enemy of good.

The masking paper and tape is off. Because of the many irregularities around the Spitfire script, I will have to recruit my wife to touch up a few areas that got missed. But otherwise it looks good for a rider. Other than reassembly, the hood is the last big item to get finished.

My building partner was in Eagle River today, and picked himself up a Brian Nelson poster at the snowmobile museum in town.

[400brian]

With the masking removed, the sled seemed to be begging for the tank and seat to be installed.

Not content to just screw them on, I set them in place and assessed how they matched up, how the tank clips lined up with their attaching holes, and how the T-nuts in the seat lined up with the holes in the tunnel.

I wound up putting a strip of 1/4" high density foam along each side of the tunnel for the tank to sit on and then pop rivetted the retaining clips in place. I engaged the seat plywood into the other half of those clips and pounded the seat forward with the heel of my hand. Eventually the gap between the seat and tank closed up.

I used a small tapered punch to find the T-nuts in the seat plywood at the rear, then carefully started a 1/4" x 1 hex bolt with a lock washer, flat washer, and fender washer into the T-nut. After I got both bolts started, I check to see if the taillight wire was still in sight...and of course it was not. I do things right because I do things twice! The two bolts came out, the wire moved back into place, and then the seat finally tightened down.

In the end I feel the tank and seat match up reasonably well, so we move on

[400brian]

Big day of final assembly items! The rear grab bar was installed, the snowflap, the taillight, the rubber handlebar grips, the drive belt and shield, and the last of the fuel line.

I will point again, that the snow flap we installed is not what would have came on the sled. The original was plain black and it was shorter. My grandson told me right from the beginning that he wanted a flap with the leaping deer logo. I picked his one up off the shed floor where it had been laying in the dirt for some time. We cleaned it up and repainted the logo, and he was happy with it. We might find we need to shorten it up a bit, but we will cross that bridge when we come to it. I also used the steel strip and screws to attach the flap rather than the 4 pop rivets the factory used on the Spits. I was kinda leaning towards leaving it bare, but again he said "no, I want a yellow stripe", so it went on.

With all that done we dove into the hood. It is cracked on each side and needed patching on the back. We got it patched up on the underside, tomorrow I will see what the top side needs before painting.

[400brian]

Galen was out on Friday and we got to work on getting the last big piece of the sled finished. I had done a little body work on the hood earlier in the week, and ran the palm sander over all of it with 400 grit. I painted the portion behind the windshield the OEM Blitz Black on Wednesday, so today we were shooting Emerald Green. We are under the gun as the sled is scheduled to leave for the Baraboo Steam and Gas Show on Thursday.
It was a good day!

On a side note: I did not realize that the hood of this sled is not traditional fiberglass, in fact most of the hoods Deere built aren't. The material is called SMC - sheet molding compound. One way of identifying it is by the inside surface of the part. On a traditional fiberglass part the inside surface will be very rough with the glass fibers showing, SMC will be fairly smooth. The problem is that SMC contains mold release agents that allowed it to be molded on each side and still allow it to be removed from the mold. These chemicals also prevent traditional glass resins from mechanically bonding to it. This was all news to me, so the repair we made inside the hood may not not last long. You also need to use SMC compatible fillers as well. The products required for SMC repair chemically bond rather than mechanically bond.

[400brian]

I have declared victory on the hood painting! The mission for this sled is for the grandson's first sled / rider. I hadn't really intended to paint it at all, but we have been working on a 1937 JD B tractor project for the last 3 years, and my methodology has rubbed off on him. He absolutely wanted the same treatment on his sled, so here we are.

The side decals were masked off, and the hood got a light scuff with 400 grit with the palm sander. For better results we could have shot several coats of primer and block sanded the imperfections out, refer back to the "rider" part. We are painting in a garage not a booth, so perfection is not going to happen anyway. I was surprised to see no evidence of bugs in the paint today!

We used two cans of Dennis's "Vintage Paint" rattle cans in JD Emerald Green. We stopped after the fourth coat because it was looking good and I didn't want to screw it up at that point.

I masked the Blitz Black too soon, the tape left marks in the paint, so we will have to do a bit of touch up on that after everything cures. Right now I believe the best thing to do with this is leave it alone, but it is heading for a show next Thursday, so compromises will be made. The tach and speedo will set in place next.