Monday, March 6, 2017

Odds and ends

I feel sorry for how few posts I put on here, there really hasn't been much to talk about.

So lets go back, during the short couple weeks we actually had snow I did get in a couple rides. First was the abortive ride when the '91 Jag was leaking gas. On that one we took a ride through an area where the trail passes through a deep cut in rock. Its old railroad line and a really cool spot. I got a picture there back in 2015:

What you can't really see in the picture is that right in front of the sled is a pipe or knee wall of some sort. When theres lots of snow you can ride right over and not know its there, with only 14" when we rode over there was a looong drop on the back side. I got the '91 up onto the bump and gently slid it over. I rode ahead a little and looked back, I saw the skis as Angie came over and thought she had it under control. In reality what happened is she grabbed a handful of throttle and stood the '98 Jag right up. When she landed she went over the windshield. She wasn't seriously hurt but got banged up and of course was really upset with me for "riding off without me". In reality I was gone for maybe 4-5 minutes, I looped around and back back behind her but she'd already ridden off. *sigh* lesson learned, look back more often.

There was enough snow for those two weeks that we groomed 3 times. I got more seat time than ever before but I don't think I did particularly well. I'm starting to tap the drag on posts as I go through and need to go slower and be more careful. I also haven't been utilizing the drag enough, I hadn't realized what an art there is to that. There needs to be enough snow in the drag to fill the bumps in the trail but not so much snow that the machine can't pull it. Also if theres too much snow in the drag it'll spill over the sides leaving boulders in the trail. The last time we groomed I rode with Chris, he works crazy hours and let me drive when he got tired. He promptly fell asleep and I made it my goal to run smoothly enough that he'd stay asleep. A goal like that helps me to become a better operator...

The last ride I took the 98 and went out on my own:

The '98 is a much more comfortable machine than the '91 at the cost of some speed. On the long straights the '91 maxes out at about 70mph, the '98 will only make around 60. Same 440 engine but the '91 is a little smaller/lighter and has dual carbs.
I think this summer I want to find a Z skid and track to put under the '91, with better suspension it'd be a sweet machine.

Friday, February 17, 2017

Gas tank welding

Went for a ride on Saturday and discovered that the repair I'd made to my '91 Jag's gas tank filler neck was insufficient. It leaked gas on my left foot the whole ride. Relatively safe, the exhaust is on the other side ;)

Anyway today I finally had a chance to attack the problem. I got a Harbor Freight plastic welding iron and began by cleaning the crack with the included wire brush. Then I repeatedly stabbed the iron into the plastic perpendicular to the crack. My idea here was to essentially stitch the crack back together:

That worked pretty well and when I was done I could no longer see a strong flashlight shining through the crack.

Then I took some of the filler material that comes with the iron and worked it into the repair. I'm hoping it'll add some strength. Fortunately theres a groove there anyway. Here I'm partway done:

I ran the filler material over all of the damaged part. I left the undamaged section alone, I may live to regret that...

Tested by putting in a few gallons of water, holding my hand over the filler hole and flipping the tank upside down. If I can manage to not screw it up during install it should be okay:

Right now its got a quart of denatured alcohol (all I had on hand) in it to absorb the water. I'll get more alcohol later today.

As a measure of safety I rinsed the tank with water yesterday. I'd tried to have the filler neck full of frozen water but couldn't get the water to stay in long enough to freeze. I did all the work outside, there was a good breeze and the ambient temp was below freezing. I wore a full face mask and had an extinguisher nearby. I sat in the middle of the driveway away from anything flammable and of course had lots of snow on hand.

Overall I consider this a success, I didn't get blowed up, in fact I never felt like I was really in any danger, no sizzling or fire of any kind...

Friday, January 13, 2017

A new season

After the washout that was the 2015-16 season I'm sure hoping for some snow this year. So far its been exciting and disappointing. Early season snow had things looking good and the Wednesday after Christmas I spent the morning putting up signs for the snowmobile club and the afternoon trying to get my old junk to run.
Right before Christmas I'd given it a shot and neither Jag would fire up. The '91 would pop a little but wouldn't stay running, the '98 wouldn't even pop unless I primed it with gas down the sparkplug holes. I figured dirty carbs.
The '98 has a single carb while the '91 has duals so I figured to try the single first. Access is tight but not impossible. The bowl had a soup of water and gas which was almost certainly the issue and although I did have to prime the engine with a shot of gas down the sparkplug holes it fired up and ran good. Its still got a weird bog but I *think* that might be because of how much sitting its done.

I ran out of light so the '91 waited until the next day. I pulled the carbs and found the filthiest bores I've ever seen...

See the schmoo down at the bottom of the bore? There should be a hole there, the carb on the left was totally plugged I ended up soaking it with carb cleaner and running a welding torch cleaning rod through it until I could get it to come out clean.

 The bowl from the left side carb. Both were gross but the left side was worse.

So knowing that the carbs were nasty I knew I'd need to do something about where the goo was coming from. I couldn't actually see anything in the airbox but I knew there had to be something in there. To remove the airbox the gas tank absolutely has to come out, then the steering column has to be loose. To get the gas tank out the seat has to come off leaving me with this:

Well that escalated quickly huh? I just wanted to clean the carbs and now...
While pulling the tank out of the way I realized the bottom of the filler neck was cracked. I wonder if this is why I was getting terrible gas mileage a couple winters ago.

So I got the airbox apart and evicted the mouse nest, and got it back together without breaking the old hardened plastic too badly. Then I ran some ThreeBond around the crack on the gas tank.

Threebond probably isn't the best stuff for fixing the crack but I cleaned the plastic good before I tried it and it seems to be holding well. The Threebond stays flexible and its strong against gasoline, we'll see how it lasts.

Finally probably the worst part of it all is that the seat wood is ruined and completely came apart. I'm kind of glad I found this now rather than bombing down the trail but I wish it hadn't happened at all. In retrospect the problem is I park my sleds pointed down hill which allows collected water to run under the seat rather than just running out.

A trip to the hardware store got a quarter sheet of 3/8" ACX plywood. The original stuff appeared to be 3/8" OSB but in retrospect (since the plastic trim doesn't fit) is probably 1/4"

The cut along the front is pretty important, it fits around the gas tank mount to hold the front of the seat down.

So I've got the seat base cut out and ready to go, the last step is to staple the base onto the seat and reinstall.

Meanwhile I got the carbs all cleaned and reinstalled and the sled fires up and runs nice.

Finally I wanted to at least try to prevent this from happening again or maybe mitigate the problem some. I got there by taping some hardware cloth over the opening to the airbox:

Thats quarter inch hardware cloth which is probably too big but its what I had. I usually use a couple yogurt cups of mothballs in the footwells. This spring I'll add more mothballs to the cup and I'll maybe add another cup under the hood.