Alumacraft MV1448 Seadoo IB jet, Still jetting

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[url=https://www.tinboats.net/forum/viewtopic.php?p=322924#p322924 said:
RiverBottomOutdoors » Today, 09:44[/url]"]Slipping the PVC over the seat pedestals......genius! Why the hell didn't I think of that????

Yep, sadly it took 2 trips to Lowe's and a trip to Home Depot looking for fittings before I simplified my A frame design to a 'T' post design. The posts are only 33" and I'm around 5' between posts so the whole contraption is pretty stiff and lifts off easily. I doubt I'll ever glue it together as it doesn't move around with the tight slip fits.
 
Been spending the day tinkering with finishing the front deck and figuring out how I'm going to get my foam insulation under the front deck framework and then hold it there. Seems a couple cans of great stuff in a garbage bag and I could be done but that seems too simple...

I checked the shipping date on my roll of carpet and it's from 2010. Yep, might have been a bit premature in ordering it way back then.

I'll take some pics later, the deck looks the same except I should lose anymore fish under the floor.
 
The regular Great Stuf will soak up water eventually, which is a pita to deal with down the road (ask me how much fun it was to get the waterlogged foam out of my Tracker.) However, they do make a minimal expansion Great Stuf for insulating door and window jambs, I think it may be closed cell foam, so that might work
 
I agree with catman steve on this. Great Stuff is not so great, it is a water magnet. I had a lot of fun digging it out of my jetboat when I re-did it with the 4 stroke engine, as it was waterlogged, and stunk worse than a paper mill (anaerobic bacteria in the bilge) It also caused some corrosion to my fuel tanks, nothing to the point of leaking, but I did TIG weld some of the really bad oxidized areas on the tanks, just to be safe.

It MIGHT work if you blew it into some really heavy mil plastic bags, but if the bag gets one hole in it, the foam is going to soak up water like a sponge. They can advertise it as closed cell all they want to, but it's not the same thing.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=325399#p325399 said:
PSG-1 » Today, 09:11[/url]"]I agree with catman steve on this. Great Stuff is not so great, it is a water magnet. I had a lot of fun digging it out of my jetboat when I re-did it with the 4 stroke engine, as it was waterlogged, and stunk worse than a paper mill (anaerobic bacteria in the bilge) It also caused some corrosion to my fuel tanks, nothing to the point of leaking, but I did TIG weld some of the really bad oxidized areas on the tanks, just to be safe.

It MIGHT work if you blew it into some really heavy mil plastic bags, but if the bag gets one hole in it, the foam is going to soak up water like a sponge. They can advertise it as closed cell all they want to, but it's not the same thing.

I was joking :wink:

Started cutting up my 1" rigid foam this morning and ended up using a couple extra 23" insulation supports I had left over from doing my garage roof to pin the board together. It looks a little funky but worked out well. That section of the bow stays dry so I went all the way to the floor and used the existing uprights to hold the block of sheets in place. Now on to the other side and then cut up some floor padding.
DSC01685_zpsd0940bbb.jpg
 
Ten minute ride home tonight... And yes, I was ducking down behind the depth finder.

DSC01716_zpsa301c38a.jpg


No pics of the fish, they were all little guys.

I'm thinking about naming the boat 'Bug Buster'... Anyone have a better idea?
 
LMAO!

We just got back from Cape Lookout this afternoon, spent 2 days camping on the beach. First night was nice, but last night, the wind died down, and the no-see-ums came out in full force, and managed to hitch a ride on us when we got into the tent. Inside the tent looked like Ranchero50's glasses. :LOL2:
 
Great build! Good job! both of you
Ive been making my living fixing pwc's for the last 23 years and bikes before that. I do have couple questions ??? Ranchero are you still running the first original engine you got from SBT?
And PSG-1 Are you really sure you want to go to a 3 cyl 4stk from Bombardier?? I see supercharger failures at least once or twice a month and at least 2 engine failures a year but Ive only condemned 2 Yamaha 4stks sense 2002! I see around 150-200 pwc repairs a season here on the lake in Texas seems to me a Yamaha supercharged 1800 would be a far better choice.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330086#p330086 said:
DieagoMan » 41 minutes ago[/url]"]Great build! Good job! both of you
Ive been making my living fixing pwc's for the last 23 years and bikes before that. I do have couple questions ??? Ranchero are you still running the first original engine you got from SBT?
And PSG-1 Are you really sure you want to go to a 3 cyl 4stk from Bombardier?? I see supercharger failures at least once or twice a month and at least 2 engine failures a year but Ive only condemned 2 Yamaha 4stks sense 2002! I see around 150-200 pwc repairs a season here on the lake in Texas seems to me a Yamaha supercharged 1800 would be a far better choice.


Thanks for the compliments! And welcome to the board! 8)

You're right about the Sea Doo supercharged engines, I have heard a lot of bad things about supercharger failure on these. It was my understanding they had fixed the problem after about 2008, but maybe I'm wrong about that. I haven't heard very much about the 1800 Yamaha SHO, but after my experience with my FXHO and my VX110, I think Yamaha engines are outstanding! In fact, I have someone who is wanting me to build them a jetboat similar to mine, and he asked what kind of engine I recommended, I said a VX110, FX140, or FXHO. We're going with a VX110. Should be a great boat when we get it done.
 
I would like to see your boat run the opti again and you have one of the skat trak or Riva pumps and stage 3 kits. The Skat trak twin drive impeller also looks promising!
they are a way more efficient pump and the stator design really does a great job straightening out the water flow. I remember the tech rep at Yamaha telling me back in 2002 that they would never build a ski with a top true speed of over 65mph because they didn't want to get people hurt and he also said the worked on pump design to get great 0-65 acceleration but limit top speed! Is this him saying what he thinks or what he knew I don't know?
Think about it a minute. you know the big three pwc company's could easily build a 700-800 pound 100 mph machine if they desired to. Also I wished I was closer to Ranchero because I have at least one of every impeller Seadoo made from 1992-1999
I for kicks would lkie to see him try a 580 3 seater impeller or one from a 1994 seadoo explorer dingy 12 ft boat
Seadoo did change in 08 but they still want yo to service charger at 200 hrs instead of the 100 and if you go that route I hope your buddy has the candoo software to reset maintenance clock when you service so it dont keep annoying you. and the newest 2010 up I believe reduces HP if you don't.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330098#p330098 said:
DieagoMan » 8 minutes ago[/url]"]I would like to see your boat run the opti again and you have one of the skat trak or Riva pumps and stage 3 kits. The Skat trak twin drive impeller also looks promising!
they are a way more efficient pump and the stator design really does a great job straightening out the water flow.


I have looked at the skat trak magnum pumps, but the price made me flinch, 1200 dollars. But I suppose it's worth every penny, I believe these pumps are stainless, correct? One day, I may bite the bullet and get one of these. As for the impeller, I'm running a Solas Concord YD-CD 13/19 swirl impeller. It has more than enough hole shot, I'd like to have more top end, but really don't know what pitch I should have Impros modify it to. Also, I am running the wet wolf AAT cone on the stator, which has helped to reduce cavitation somewhat.

As for the stage 3....actually, I'm running two of the stages already. I removed the stock air filter and have the Riva filter installed, along with velocity stacks. I am only running the aluminum waterbox, but not the secondary muffler. The only thing I have not done is modified the rev limiter.





I remember the tech rep at Yamaha telling me back in 2002 that they would never build a ski with a top true speed of over 65mph because they didn't want to get people hurt and he also said the worked on pump design to get great 0-65 acceleration but limit top speed! Is this him saying what he thinks or what he knew I don't know?
Think about it a minute. you know the big three pwc company's could easily build a 700-800 pound 100 mph machine if they desired to. Also I wished I was closer to Ranchero because I have at least one of every impeller Seadoo made from 1992-1999
I for kicks would lkie to see him try a 580 3 seater impeller or one from a 1994 seadoo explorer dingy 12 ft boat
Seadoo did change in 08 but they still want yo to service charger at 200 hrs instead of the 100 and if you go that route I hope your buddy has the candoo software to reset maintenance clock when you service so it dont keep annoying you. and the newest 2010 up I believe reduces HP if you don't.


Good to know. I think if I do go with the supercharged engine for a future build, I'll stick with Yamaha.

Here's a thought on how to wring more speed out of a Yamaha 4 stroke. These engines use a 1.47:1 reduction gear, which steps the impeller speed down! For example, at 10K RPM, the impeller of my boat is only turning 6800 RPM.

What if there were a way to modify the gear ratio? Even just a little bit? If we were to change from a 1.47:1, to a 1.25:1, at 10K, the impeller speed would be at 8K, which is about as fast as you want to turn one without risking thru-hull bearing damage. Once the impeller starts turning over 6K, every few hundred RPM makes a big difference. Imagine what another 1000 RPM would do!
 
I'm no genius but Ive read you saying this before? Ive rebuilt several of the older yam thru hull why do you say it wont take it? on the gp's and XL's the bearings on the thru hull is not much different than the ones in the pump and they were direct drive. I will have to look at the next sho i work on but ive never had any problem or payed any attention to the thru hull on 4stk. I will tell you this the VX is different I had to pull a drive shaft on one last year and it no longer pulls with the pump you have to raise engine like a kawasaki and pull it towards the bow under engine. Im also not a hot rod genius Im a mechanic the moneys in repair not racing lol hell I cant even remember sitting here what the rev limit was on a 1200 2stk lol wasnt it around 8000
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330086#p330086 said:
DieagoMan » Today, 19:23[/url]"]Great build! Good job! both of you
Ive been making my living fixing pwc's for the last 23 years and bikes before that. I do have couple questions ??? Ranchero are you still running the first original engine you got from SBT?
And PSG-1 Are you really sure you want to go to a 3 cyl 4stk from Bombardier?? I see supercharger failures at least once or twice a month and at least 2 engine failures a year but Ive only condemned 2 Yamaha 4stks sense 2002! I see around 150-200 pwc repairs a season here on the lake in Texas seems to me a Yamaha supercharged 1800 would be a far better choice.


Yep, that SBT rebuild has served me well, that and the rev limiter when I'm goofing off. Those guys were enthusiastic and my thread on PWCtoday had a lot of views so maybe they gave me a better than average one. I've done minimal maintenance work to it and didn't even winterize it last year after changing the drain lines so it drains dry.

I tach out at 6700rpm WOT and am running the '95 XL pump and sharpened impeller. I have more cavitation issues with the inlet since I added the pods but it runs flatter and is safer in the squirelly areas. I was thinking about adding an old bread knife blade to the back of the grate to help cut off the weeds that get grabbed when I'm idling through the much.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330104#p330104 said:
DieagoMan » 6 minutes ago[/url]"]I'm no genius but Ive read you saying this before? Ive rebuilt several of the older yam thru hull why do you say it wont take it? on the gp's and XL's the bearings on the thru hull is not much different than the ones in the pump and they were direct drive.


I'm using an XL1200 pump, with the .700" diameter shaft (there were 2 sizes, if I remember correctly, I think the other one was .750") I think the rev limit on most direct drives is around 8K. Above that, I think the impeller would start to cavitate, and vibration caused by it at those speeds is probably more apt to cause damage. Just an educated guess, I may be wrong about that.



I will have to look at the next sho i work on but ive never had any problem or payed any attention to the thru hull on 4stk. I will tell you this the VX is different I had to pull a drive shaft on one last year and it no longer pulls with the pump you have to raise engine like a kawasaki and pull it towards the bow under engine. Im also not a hot rod genius Im a mechanic the moneys in repair not racing lol hell I cant even remember sitting here what the rev limit was on a 1200 2stk lol wasnt it around 8000

My boat's a little funny about how you have to remove the pump, too. Since I cut the driveshaft and pump housing short to allow the FXHO to fit within the existing engine compartment, there is no shaft exposed above the pump housing, the engine coupler screws directly onto the threads. As a result, I had to cut wrench flats on the driveshaft, behind the bearing area, which means to put a wrench on it, you have to do it from under the boat! Also, because there is no shaft extension, you can't just slip the pump assembly backwards enough to put the coupler wrench onto the coupler and unscrew from the shaft. The engine has to be unbolted and moved forward! A little bit of a PITA, but I had to work within the existing space I already had from when the 1000cc tigershark engine was in the boat, I didn't feel like having to re-build the entire pump tunnel to set it back.

On any future builds, though, I will allow an extra 6 inches so the driveshaft and pump is easier to remove!
 
Least we forget... One of the coolest **** builds on here :USA1:
 

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