FX-1 FX1 grafting 144 pump tunnel

[samsmith87]

I am collecting parts for my FX1 build. I am going to cut the 144 pump tunnel out of a sn sj and fiberglass into my FX1.

My question is what drive shaft do i need to run for the people that have done this. The SJ drive shaft or FX1 or are the the same?

 

[special fx]

They are different shafts.

 

[samsmith87]

They are different shafts.

Which one am i going to need?

 

[kcmasterpiece]

I took the sj tunnel and pump cavity. I had to have a custom shaft made. I forget the length though. Im sure you can use an SJ shaft and build the ski around that. the only problem is it will be more difficult to make work since you will have one more measurement to keep track of.

 

[kcmasterpiece]

you may have some issues with the bulkhead too. the tunnel for mine starts where the stock did, but the sj tunnel is 2 inches or so longer. the sj shaft was too short for mine. there may be a little bit of room to move the tunnel forward an inch or so, but you will sacrifice a little bit of stability and high speeds.

 

[samsmith87]

I took the sj tunnel and pump cavity. I had to have a custom shaft made. I forget the length though. Im sure you can use an SJ shaft and build the ski around that. the only problem is it will be more difficult to make work since you will have one more measurement to keep track of.

Thanks KC.

I love your ski going to be similiar. I am going 144 tunnel and Toms21 tubbies wider tray. Why did you end up going with a custom driveshaft. I was planning on be able to go off drive shaft length to get my measurements right.

 

[kcmasterpiece]

 

[kcmasterpiece]

I didnt want to have to worry about it. I just put the tunnel in straight and then measured for a DS. then sent out a raider shaft cut and re splined.

 

[samsmith87]

you may have some issues with the bulkhead too. the tunnel for mine starts where the stock did, but the sj tunnel is 2 inches or so longer. the sj shaft was too short for mine. there may be a little bit of room to move the tunnel forward an inch or so, but you will sacrifice a little bit of stability and high speeds.

Cool thanks. I really dont care about high speeds. Also where is the write up for what you did for reinforement? I saw one of yours on pwc but all the pictures were dead. What do you fill the bond line in with?

 

[kcmasterpiece]

i used epoxy and cabosil. just smush it in there and squeegee flush. let it tack up a bit then through down the glass.

 

[200%Absolut]

You can use SJ or fx1 shaft depends on what do you want. i don't know if the fx1 shaft will be a drop in as i choose the SJ .

FX1 shaft for stock location pump, SJ for setback . If you choose setback option you will have to make an extented wear ring and a spacer for the steering cable.

 

[tom21]

fx shaft and sj tunnel will put everything back where it originally was.

 

[samsmith87]

OK well, what route would you recomend me going. I ride waves of Lake Michigan and some flatwater. I want a ski that is flickable and only bottom end. I dont care about going fast. I have a SN now and it feels like a boat to me. My friend has an all stock FX1. Its fun to ride but has no bottom.

 

[kcmasterpiece]

If you choose setback option you will have to make an extented wear ring and a spacer for the steering cable.

Not if you do it the way i did it. Use the entire pump cavity. it makes it so much easier. no extra wear rings or spacers and you dont have to mess with the pump mounting. just cut everything as evenly as you can. make sure it all fits well with a little bit of wiggle room to align it.

Its was so simple, i felt like i was doing something wrong and it would fail on the first ride. but its didnt and its still going strong.

plus, the set back pump shoe is the best way to go. if you keep the pump shoe in the stock location, the ski gets really squirrely and unstable because the pump tunnel or center of suction, is too close to the center of gravity. it needs to be further back.

 

[tom21]

OK well, what route would you recomend me going. I ride waves of Lake Michigan and some flatwater. I want a ski that is flickable and only bottom end. I dont care about going fast. I have a SN now and it feels like a boat to me. My friend has an all stock FX1. Its fun to ride but has no bottom.

well it looks like kc has a solution for an easy install with use of sj shaft for a setback pump and the other way is to use the stock fx dimensions with the fx shaft. we have a setback but it is accomplished with a spacer. to me it feels like my bigbore sj but lighter and more nimble.

I have ridden the fx with a 144 installed in the factory fx shoe that I ground out to about 140mm. it felt pretty good.

I think with either install you will get a pump that is ready for more power and that is probably gonna be another necessary step to getting to what you want.

I am not sure how kc did his(sounds like its right) but I cant stress enough that you absolutely need to make sure your pump and tunnel is aligned when you install it.

 

[samsmith87]

Ok i am going to put in an order at UScomposites what should i get for material. How much and what. As well as i am doing all this fiberglass i might as well reinforce the hull as well.

Also when i am doing this, what is the best way to make sure my pump is lined up perfectly. I am guessing that after the pump is bolted in, as long as the driveshaft goes into the midshaft smoothly it would be correct.

Any help will be appreciated thanks

 

[AAlamo]

Ok i am going to put in an order at UScomposites what should i get for material. How much and what. As well as i am doing all this fiberglass i might as well reinforce the hull as well.

Also when i am doing this, what is the best way to make sure my pump is lined up perfectly. I am guessing that after the pump is bolted in, as long as the driveshaft goes into the midshaft smoothly it would be correct.

Any help will be appreciated thanks

In order to align your pump and driveshaft, you need to make a tool that will ensure your driveshaft comes dead center through the bulkhead. You cant use the midshaft as your center point because of the rubber lining. From experience, you would be surprised how much you can angle the pump inside the midshaft. And if your driveshaft isn't perfectly aligned, you'll have multiple problems. So what I did when I put in the 144 pump section in my fx was I used a piece of aluminum that utilizes the three bolt holes of where the midshaft bolts to the bulkhead and then used an impeller tool in the middle of the aluminum to ensure my driveshaft was properly aligned. This is not a new idea I believe sanoman and tom21 have both made tools like it way before I was on this site so I want to give credit where credit is due. Others have probably done something similar those are just two of the people I can remember doing it. As for reinforcement, its all personal preference for glass. I used 17oz biax and a layer of carbon Kevlar. If I had to do it over I would only use 12oz biax to save some weight. But I did the 17oz and carbon in both the engine compartment and sides of the tray, proably a little too much. If you've got anymore questions shoot me a pm I just finished my fx1 project so all the steps are still fresh in my mind I just haven't had time to update my build thread. Anthony

 

[tom21]

be aware that the spline tool is still sloppy, we measured the overall travel of say 2inches and split it. centered if off the slop so to speak. not exactly precise but at least we cut the guessing down to minimum.

 

[samsmith87]

Thanks for your help. Do you guys have any build threads with the process you can link me. Will be picking up the hull this weekend and ordering fiberglass, have everything else I need. This will be my fall project.

 

[tom21]

I have like 2 pics, when Im working I never stop to think about pics just the work ahead and having resin on my hands most of the time and expensive smart phones are not a good mix.