I'm going out on a limb here guys... I've been lurking for a few months now and have not seen what I'm looking for so I figured I would join and ask my question. Has anyone experimented with using one of the manufactured lower drive units on an air cooled vw motor? I have my motor built and have started to fabricate the drivetrain, but am wondering if it wouldn't be a better idea to use one that has already been designed and tested...If it will work.
Go ahead and throw your thoughts back at me... I can take it.

Look in the video section there is a long tail with a vwmotor on it

Thanks... I did see that one before. I have a friend that built a longtail VW for his 1650 Lowe. I tried it on my boat, but want to try to build a SD drivetrain instead. I'll take some pic's and keep you guys posted with my progress. I'd love to put twin SD's on my 1872 Sea Ark, but I just can't swing the 12-14k right now. If this VW works out, I should have under 3k in it all, and that includes the completely rebult 1600cc motor which should put out about 60hp. I'll be asking more questions the deeper I get into this.

^ Dats gotta be heavy.

ya and loud a** the fu$$

Ok - here is a semi crazy thought - what about mounting the motor
in the middle of the boat and using a flexable drive shaft - or - hydrolic
positive pump to positive pump to transfer the rotational energy back to the surface drive.....

An aluminum gm 3-cylinder would be sweet, they get about 60 hp, especially if you can get a fuel injected one, just have to have a radiator and electric fan. A lot lighter than a VW. Go to the junk yard and hunt for a sprint or a metro. A guy down the road has a carb'd one on a longtail, pushes his 20' around 20ish.

Hey Quakshot... Now that's what I'm talkn' about. What can you tell me about that set up? Is it yours? That is exactly what I had in mind and I need to pick the guys brain that built it. I have the swivel and mounting system just about finished and the motor is complete. Next step is the drive train. I'm estimating total weight to be about 260-275. That really shouldn't be a big problem in my boat though. I'm building it for bowfishing and running in the shallows, not so much the mud.
Thanks for the feedback... keep it coming.

It's been awhile, but I promised pic's...so here they are. Many thanks to Quackshot for providing a bunch of helpful information. The motor is mounted and running and I am working on the box to house the pulleys and bushings now. Should have the prop shaft and housing pieced together soon.

A couple more pic's of ol' NIGHTMARE

I have a 2004 Hyper Belt houseing with top cover I'll sell.

You got a pic? I have no idea what that housing looks like.

This is a pic of the houseing when it was on my boat. I only have the houseing top cover and the brace the goes form the houseing to the shaft. I no longer have the shaft.
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that's cool stuff man! keep up posted on your progress, and how she runs!

yeah post up a review with your speeds when you get it completed....looks bad ass

RichardB.... Thanks for the offer, but I think I'm going to run with what we are building right now. I've already figured out how to adjust the belt and pulleys with what I have designed... not sure if it would work with the unit you have. If it doesn't work out, I'll be in touch.

No problem it’s just sitting around if you end up needing it let me know.

I am building a pontoon boat with a vw engine and have gone with an Alpha II unit. Has anyone some experience with Alpha sterndrives? I need some sort of gimbal bearing to attach the sterndrive shaft to the engine. I think that quackshot sent me some pics of his set up for a short tail and had welded and turned a shaft to the flynut of the vw. I want to do something on the same idea. I am wondering if the shaft of the sterndrive will have to slide in and out of the gimbal bearing to allow for the steering and trimming of the unit. Any ideas?

Archy,

Is the bell housing on the vw a vw buss bell housing? Did the hole that is in the pic line up with the shaft? And did you use quackshots idea of welding a shaft onto the flynut?

Thanks

Mark

Mark,
Good question on the bell housing. I really do not know if it is out of a bus or not. I picked it up from a local VW rebuild shop mainly because I needed the starter. While explaining what I was making, the techie guy suggested I use the VW short shaft that the clutch plates ride on to drive the pulley instead of having to worry about welding a shaft on the gland nut. So that's what I am using. I turned the end of the shaft down to 5/8" to fit the bushing and pulley on and the end currently exposed will rest in a 5/8" flange bearing mounted to the lid of the box. The other end actually goes inside the gland nut attahced to the back of the crank and rides in the needle bearings. I used some JBWeld to lock the clutch plates together and bolted them to the drivewheel. The clutch plates are splined to match the short shaft... that's what will drive everything. Hope that answers some of your questions....Chip

Well.... after a long winter of cutting, welding, screwing, re-welding, bolting, grinding, cutting, and re-welding............ NIGHTMARE made her maiden voyage with her new VW powered surface drive. I made 7 or 8 trips up and down the river and have a few minor things to adjust (carb and a small leak in the box), but she did what I designed her to do. I also need to make up a cavitation plate for her. Many thanks to Quakshot for providing all of his information and getting me pointed in the right direction. Here's some pic's.

Sweet
I have been waiting to see the finished product. What kind of speeds are you seeing?

More pic's

In the water....

Dude... that is fukkin beast. I just posted a gm motor on a lt some dude built, but this thing is awesome. Let us know some speeds and stuff.

Speed is SLOW right now.... it's the first time out for the motor as well so I didn't want to push it. I also need to play around with the height of the prop as it relates to load on the boat. And I'm guessing that the cavitation plate will provide a little better performance as well. honestly, I'm not looking for fast... we run the river with lots of rocks. Plus, this boat is HEAVY. Like Deathmetaldukk said, "she's a beast". I'll post some more info once I get her tuned in.

dude, that thing is a monster!! Good job man!

This may give you some ideas.
http://godevilalaska.wordpress.com/
I can hardly wait for the ice to break up on the rivers.

My Cav Plate,just a couple pieces of aluminum angle bolted to a flat plate

Put the stinger pipe on the end of the open headers tonight. Sounds much quieter from the steering stick now. Also talked to a VW guy about the carb tuning and he pointed out an air leak in the intake manifold. Fixed that and she already runs better. Will build the cav plate before the weekend. And it will look VERY similar to the one on Quackshot's rig. Only diff is stainless vs. aluminum. Anyone know if the angle is critical? I mean I'll run it from the top of the prop shaft housing to about an inch above the prop. Should I make it adjustable for any reason? Just wondering if it really matters.

What is that between the lower unit and the boat,some type of trim adjustment?

It serves two purposes..... to adjust the trim as you mentioned. But the main reason it's there is to handle/relieve most of the torque and position it directly into the back of the boat instead of having to go through the mount at the top of the transom. I used a sealed ball joint to allow for the movement and then made a slip joint with a threaded inside pipe to provide adjustment. It works great. I can actually sit on the back of the prop shaft and the motor doesn't move.

What happens when you hit something that is submerged i.e. stumps or rocks

same as quack asked, i like the idea of the location. you could also use a trim unit in that location and have adjustalility to the trim. plus it looks like you are takin alot of stress off the transom. but what if you hit somthing?

It's a two piece unit. The threaded shaft that is attached to the ball joint actually slides inside of the piece welded to the back of the box. It allows me to lift the motor manually to take the prop out of the water, and bounce up if the skeg hits something. The outside piece welded to the box actually slides back down and comes to a fixed stop against the washer and nut on the threaded piece. Let me know if that answers your questions. If not, I can take a few more detailed pic's of it.

I think I'm going to try running it awhile without the cav plate. I've been checking out the factory units and most don't run one, so I'm thinking it may not be a "have to have" for this set-up as well. I'm gong to play around with the prop position next time out and see what happens.

I was informed that some of the pic's no longer show up... so here's some updated one's.

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She's wearing hydraulic's and a cav plate now.

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And the Nightmare has been very productive!

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