Make-A-Wish sled restoration project.
- Thread starter snoluver1
- Start date
skiroule
Well-known member
I think this is pretty funny. Spoken like a true sledder - none of this wimpy "let it idle for a while and see what happens". Let's crack that throttle and see what she'll do.
Running for two minutes? I've known marriages that haven't lasted that long. Carb issues aside, I can tell you that if I got an engine to fire up that hadn't been run for a decade, there would also be bubbles in the champagne (or at least the beer).
Well Done!
Well, my suspicions of Taiwan crap parts have been confirmed. I found one of the diaphragm gaskets was cut incorrectly and partially blocking off the pulse passage. I trimmed the gasket and she started pumping fuel.
Now I have the exact opposite problem. The carb is flooding out. The piece of crap overhaul kit manufactured by SPI, had a different needle and seat, so I had to reuse the original. The threads were cut wrong on the low and high speed jets, so I had to reuse the originals. The welch plugs were made of aluminum instead of steel, and it didn't come with a inlet needle gasket. Basically the only usable parts out of the entire overhaul kit were the diaphragm set, and even that gave me problems. Long story short, any one of these components could be causing the problem. Basically, what it comes down to is I have one of two options: find a different overhaul kit with the correct parts (MADE IN AMERICA), or find a Mikuni carb and swap it out. Either case, its going to take some time to get this situation resolved.
The good news is, I know the engine WILL run, as soon as I get the fueling issue straightened out.
Now I have the exact opposite problem. The carb is flooding out. The piece of crap overhaul kit manufactured by SPI, had a different needle and seat, so I had to reuse the original. The threads were cut wrong on the low and high speed jets, so I had to reuse the originals. The welch plugs were made of aluminum instead of steel, and it didn't come with a inlet needle gasket. Basically the only usable parts out of the entire overhaul kit were the diaphragm set, and even that gave me problems. Long story short, any one of these components could be causing the problem. Basically, what it comes down to is I have one of two options: find a different overhaul kit with the correct parts (MADE IN AMERICA), or find a Mikuni carb and swap it out. Either case, its going to take some time to get this situation resolved.
The good news is, I know the engine WILL run, as soon as I get the fueling issue straightened out.
skiroule
Well-known member
SL1, Don't know if it would help but I know for a fact that I can get my hands on a stock Doo Tillotson (Don't know if it's an HD or an HR). The catch is that it's on a 440 so might be jetted a little heavy. Probably a more common model than what you're dealing with though.
If it would help, say the word. I think I could get it to you this week. Otherwise, lots of Mikuni's on VintageSleds.
If it would help, say the word. I think I could get it to you this week. Otherwise, lots of Mikuni's on VintageSleds.
Tell you what Skiroule, give me one more night to mess around with the one I have, and let me see if I can find the smoking gun. If I can't determine for sure whats causing the problem, it might be worth changing it out. This carb I have seems to be a bit of a misfit, and I have already determined it is not OEM. An HR is much more popular, and I think there are several different suppliers with rebuild kits for them.
The other side of the coin is the people "in the know" suggest the best thing you can do for these old Rotax motors is to hang a Mikuni on it. I suppose it would come down to cost and hassle of changing to Mikiuni, versus cost of a different Tillotson plus another rebuild kit.
The other side of the coin is the people "in the know" suggest the best thing you can do for these old Rotax motors is to hang a Mikuni on it. I suppose it would come down to cost and hassle of changing to Mikiuni, versus cost of a different Tillotson plus another rebuild kit.
I think I found one smoking gun. I drove one of the welch plugs a little too deep and I think its leaking. I can't blame that one on Taiwan, totally my fault. I'm not sure if thats the only issue, but its all I could find that would definitely cause a flooding issue. I guess its worth trying to find another plug and see what happens. The hunt is on!
skiroule
Well-known member
Hopefully the plug is the source.
I did discover something tonight when I went out to check the inventory. The carb I have is, in fact, a Mikuni off a 440 Rotax fan. I just never took a good look at it before. The throttle cable works but it's pretty crappy and the choke cable is frozen (unfortunately). I would think that most Mikuni linkage would fit your flipper and it's pretty common hardware so I think the linkage issue could be overcome
If push comes to shove, you can have it for the standard discount.
BTW, the engine was in a 74 T'NT so I know the throttle cable would fit your flipper.
I did discover something tonight when I went out to check the inventory. The carb I have is, in fact, a Mikuni off a 440 Rotax fan. I just never took a good look at it before. The throttle cable works but it's pretty crappy and the choke cable is frozen (unfortunately). I would think that most Mikuni linkage would fit your flipper and it's pretty common hardware so I think the linkage issue could be overcome
If push comes to shove, you can have it for the standard discount.
BTW, the engine was in a 74 T'NT so I know the throttle cable would fit your flipper.
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Its alive!!!!
Burning gas baby!!
It was the welch plug.
I just want to give a big thanks to the good folks at Novotny Sales in Johnsburg IL.
http://www.novotnysales.com/
My bud Mfire8 called over there and talked with their mechanic Mitch. He said he had some welch plugs laying around in an old box on the shelf, and gave them to us at no cost.
I picked them up tonight and got it back together. Two pulls and she was breathing fire! I'll try to get a video up tomorrow.
I'm a very happy camper!! Time to crack a beverage and celebrate!
Burning gas baby!!
It was the welch plug.
I just want to give a big thanks to the good folks at Novotny Sales in Johnsburg IL.
http://www.novotnysales.com/
My bud Mfire8 called over there and talked with their mechanic Mitch. He said he had some welch plugs laying around in an old box on the shelf, and gave them to us at no cost.
I picked them up tonight and got it back together. Two pulls and she was breathing fire! I'll try to get a video up tomorrow.
I'm a very happy camper!! Time to crack a beverage and celebrate!
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D
Deleted member 10829
Guest
Super! That has to be a great feeling to see all of your hard work pay off!!! I'm very impressed and you should be very proud of what you guys have accomplished.