# Shaft length.... Am I doomed?



## micaheli (May 19, 2013)

Bought a boat with a Yamaha P200TLRW (200 horse VMAX 2stroke). On this boat was a 5" extension and a prop drive. Included WITH the boat was an AA series outboard jet that we were assured had been on this boat before. I've been fishing in some skinny water and wanted to get the outboard jet going.

I disassembled the jet drive down to it's main components to determine which parts were missing. I then contacted my local Yamaha dealer and purchased the necessary yamaha and outboard jet components. 

I admit that I was a bit naive and never measured the shaft length of the jet drive vs my existing prop drive. That blew up in my face a bit this weekend. Obviously, I want to eliminate the 5" extension entirely and run the jet drive up against my motor as high as possible. I have a 25" transom. After some measurements, I've determined that with my engine 2-holes higher (where bolts had clearly been before according to wear rings) and the jet drive up against the upper drive casing, the jet drive would be PERFECTLY aligned with the top of my tunnel. I then pulled my prop drive and instantly realized that a couple things were wrong....

1. The shaft on the jet drive was clearly 5" too long. 
2. The PO appears to have brazed a copper pipe extension to the water pump pipe. Meaning I'd have to cut that off to it's previous size or near it so I can un-braze it with a torch. (UGH!!) 

I then scoured the internet to see if they made a shaft shorter. My current shaft is 7/8", 20 spline and 30 11/16" long end-to-end. By my math I need one that is 25 11/16-ish long. No such shaft exists on outboard jet's parts lists. No way I can run this jet drive with the 5" extension - mainly because A: I'd need to raise my transom 5" and B: It's just silly to think that I'd need to extend my shaft AND raise my transom... Ludicrousness... 

Before I go cutting that copper water pump pipe, I want to make sure this is even an option. I'll give Outboard Jets a call tomorrow, but I'd love to hear what you folks think...

What should I do?


PS. First post! WooHoo!

--Micah


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## River Rider (May 20, 2013)

Do you have some pictures to show what exactly you are talking about? It is hard to see what you are taling about but if I am reading your post right then you have a long shaft prop and a short shaft Jet? Also you mention a tunnel is it a prop tunnel or a jet tunnel? Post some pictures and I am sure someone could get you going in the right direction.


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## catmansteve (May 21, 2013)

I'm with River Rider, I think the first question is what kind of tunnel do you have? A jet tunnel is 2"-3" depth, prop tunnel is 6" or more, and anyone that's ever messed with jets can tell you prop tunnel + jet = no go. Is 25" from the top of the transom to the bottom of the boat or to the top of the tunnel? A long shaft jet needs around 27" transom height (hence why you would need to move it up a couple bolt holes) 

Was the boat built with a tunnel or was the tunnel fabricated? Also, you might could just have the tunnel welded shut, most people will tell you unless you're running very nasty, rock infested water that a tunnel is more trouble than it's worth.


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