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(3/19/00) My axle problems are solved! - so I though.....

Anyone following the progress of the Moskito probably knows about the problems I've had with the axles being pulled out of the transmission CVs. I have been searching for a way to fix them and this weekend, I found the answer.

I went over to Slim's shop this past week to work on and play with my helicopters. It just happens that he specializes in Porsche repair. In one of the rooms of his shop he had a 911 up on a stand with the engine and transmission pulled out. There it sits behind the Porshce and on the tranny I notice a set of output stubs with the flanges that the CVs bolt to. Hmmm, what's this? These looks like they could be made to work on the Moskito.

I run home, grab my spare CV and go back to Slim's to see if it fits the Porshce tranny flanges. Gee, it's is close, but it's (the flange) a bit too big. It ends up being 112 mm in diameter. "Hey Slim, got any other of these flanges that fit this CV???

"Sure!" He pulls open a drawer and there sits a pair with a 100 mm diameter. "These are from a new 915 tranny (915 being the tranny's designation - not a car). These are in the newer 911's. I'll make you a deal - 50 bucks each. They retail for close to a hundred." I walked out the door, my newly found prizes in hand.

So, now what I have is a set of Pilot CVs and set of Porsche CV flanges. Gotta make them into one part. I pull out the chop saw, cut almost all of the cup off the Pilot CV and then cut the stub off the Porsche flange.

Time for some machining. The stuff that the flanges and the CV cups are made of is some HARD STUFF! Thankfully, I have some carbide tipped tooling. I started out by cutting down the Pilot CVs so all that was left was .375" of the original cup. This would give me room fit the Porsche flange into it. Next, I machine the back of the Porsche flange so that it had a lip and groove that would fit in the cup, and was deep enough that it bottomed out in the CV cup. I now had two welding surfaces - one all the way around the outside edge of the CV cup and one around the inner lip of the Porsche flange. I quick check and with my machining and welding, I ended up only being about .015" out of shape. I chucked the my new CV mounting flange in the lathe, refaced the mounting surface and everything now runs true.

A quick test fit and I'm as happy as a clam. The new flanges fit nice and close to the tranny, giving me about two more inches of axle length so my swing angles drop even more, and they don't interfere with anything. I was a bit worried about the belt drive system being in the way, but it ends up that I have about a quarter inch of clearance. Perfection!

Now all I have to do is get one more CV joint and cut/weld up a set of test axles and I'm up and running!!! I'll be able to call Sway-A-Way and just order a type II axle in the correct length now! As I recall, they make them in 1/4" increments up to something like 30" - don't quote me on that, though.

As soon as I get this darn cast off my arm and we have some good weather, I'll be out testing the Moskito. More to follow soon!

(4/30/00) Well, the drive train problems persist!

After getting my CV joint and installing it, I still had to make axles that would fit the CV's. This meant cutting up two sets of my existing axles and welding up one set of axles that had the Type II spines on both ends. I cut, chamfered and welded the axle halfs together and then capped the joints with .095" wall chromoly tubing. The first test run around the yard looked good - for a while. I was able to do burn outs on the concrete pad behind the garage, run up and down the driveway and generally screw around without any problems. I'd forgotten how HARD the Moskito's engine hits and how quick that thing is. Power slides around the sweeping turn in our driveway were a blast. Then, I had my problems.

Our yard is two levels. They are separated by a small creek. Heading from the lower to the upper, there's a little bump, the creek and then the uphill section that goes to the upper level. You can hit the little bump, clear the creek and land on the uphill. I took my normal line, lined up with the bump, cleared the creek and as soon as the rear wheels hit the ground again, the engine just revved up. I'd snapped BOTH axles right where the welding had been done. It's pretty cool how easily it tore that chromoly tubing lengthwise on both sides.

I've already put my call to Sway-A-Way in. Unfortunately, the new axles will once again be special order items, so I'm looking at another six to eight weeks of downtime on the Moskito.

When will it end? (:

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