My 2015 off pre-season upgrades and repairs.

[Ronnie]

I finally started to work on the boat today. Decided to go with something "easy" at first which meant the after market air filters and flame arrestor ribbon replacement. It took about an an hour and a half to start to finish, not bad. I also plan to post a narrated video of it soon.



Next weekend I may install solas aftermarket impellers from impros.

The foam I put on the hatch got soggy at the bottom edge. I tore it off and plan to replace it with 3" thick material, similar to what the 2015 240s have on their engine hatches.

 

[johnk]

I'm curios to see if props help as i found mine to cavitate off the line after removing ribbons and filters.

 

[Ronnie]

Are you using stock or after market impellers? I'm sure impros could repitch them again but am hoping that they won't need to.

 

[Ronnie]

Here is the link to the you tube video I put together on this. There isn't much to see, I just wanted to get some editing practice in.

Here are some pics that I took during installation. A good reminder for me to order some more sound absorbing foam. If you install the flame arrestor mod just be careful not to damage the rubber mount the flame arrestor and mod sit in. I can see how this mod makes the air passage smoother and allows more air in than the stock flame arrestor but I can only hope that their is a noticeable improvement (I didn't think I saw any when I did a similar mod to the sx230ho I had, there I replaced 4 flame arrestor ribbons per engine with velocity stacks).

 

[TN888]

Which sound proofing foam similar to the factory are you going to purchase?

 

[Ronnie]

Probably the 3" thick plain or adhesive backed egg crate material offered by McMaster Carr. Here is a link to the pertinent page on their website. It's pricey but I only need to redo the hatch.

http://www.mcmaster.com/#sound-absorbers/=w8yemx

I will likely redo the seal with a product from here as well. The pipe insulation I installed last year is already deteriorating in some spots. Lastly, I will put a few pieces of sound absorbing material in a few other places throughout the boat, like Searay uses in its quiet ride system.

http://features.boats.com/boat-cont...h-sea-ray-250-slx-with-quiet-ride-technology/

 

[johnk]

Great work ronnie.

Still using stock impellers now that ribbons and air filters changed it makes more low end power spinning the props.

have you been out on boat with upgrades but old impellers yet.

john.

 

[Ronnie]

I wish I could say yes but I don't think I will be able to go out anytime soon and probably not until after the new impellers are installed. @sysinu put in everything and had more cavitation afterwards. I think the only way to address that if it happens too me is to pull the impellers and send them back to Impros to have them repitched but I'm still hoping that I wont have to do that.

 

[d_coyne1984]

What is this "cavitation" I hear you all speaking of? #rookieproblems

 

[Ronnie]

@d_coyne1984 , IMHO cavitation is what you experience when the water flow into your pumps is not smooth. That is you are pushing a mixture of water and air out of them. The result is that although your engine and impeller will spin up they will not produce the thrust/acceleration expected. My best analogy is that it is like spinning the tires on your car, only not even close to being as cool or cool at all. My experience is that it is caused by something sticking out/ not smooth in the intake or a leading on one of the blades of the impeller it self may be damaged. If you have cavitation, especially if it is severe, you will know it and if you have it you won't want it. Tracking down the source can sometimes be a real pita.

Today is install aftermarket impeller day. Wish me luck. I will try and do a better job of videoing and editing the entire process as well. Wish me luck.

 

[sysinu]

RE: Impros... they just moved locations so they were SUPER backed up getting impellers out.

They are just now getting back on top of things - I purchased new impellers instead of sending them to get re-pitched... should get them the end of the week. I need to decide if I want to install them or if I'm going to just have SVMS install them when I have them get the boat ready for spring. Still on the fence about that.

My issue was I changed too much all at once . I kind of knew I was changing too much stuff - but I'm pretty sure that my top end has the same result (it's just I can now over-rev). After the new impellers, my top end should increase a little bit.

 

[Ronnie]

In trying to remove the first impeller from the shaft I broke the crescent wrench i was using. I will try again later since the auto store isn't open yet. Looks like I need a 27mm box wrench to replace the crescent wrench in this situation. If it doesn't work I may just take these into my trusted pwc shop for them to get the impellers off the shafts. FYI the gaps between the front of the impellers and the shafts has been filled with blaster over night. I have not tried heating with a torch yet but may later today once I have the right wrench in hand.

 

[Ronnie]

So much for heating it up, that had no impact at all.

I'm waiting for some friends to call me back they have a beefier vice/bench setup and a little more hp as well. I may have to buy a bigger vice. If I can get this done today I will have to drive the parts 60 miles to a shop sometime this coming work week. Definitely not something I have time for.

 

[MikeyL]

@sysinu . I have a question. Why would a Model Year 2014 Yamaha, 1 to 1.5 yr old, boat need impellers changed, modified, looked at ?
I am quite interested in this answer. It is something I never would have considered.
Thanks in advance, Mikey Lulejian - In 76 degree sunny weather on beautiful Lake Oconee, GA, taking a break from our first lawn cutting of the year on my emerald Zoysia lawn.

 

[johnk]

use a steal tube extension about 24" long to go over wrench for leverage.

 

[johnk]

Mike if you run your boat in shallow water to much sand and dirt can wear edges down causing pressure to leak which will effect performance.

 

[Ronnie]

Funny you should say that because that is exactly what the tech at the shop did earlier today. $60 (1 hour min.) and worth every penny. Got some reinstall advice as well. By the way the shop has been in business for over a decade and the tech wrenching is last year's amateur freestyle champion.

 

[sysinu]

@sysinu . I have a question. Why would a Model Year 2014 Yamaha, 1 to 1.5 yr old, boat need impellers changed, modified, looked at ?
I am quite interested in this answer. It is something I never would have considered.
Thanks in advance, Mikey Lulejian - In 76 degree sunny weather on beautiful Lake Oconee, GA, taking a break from our first lawn cutting of the year on my emerald Zoysia lawn.

Tuning, primarily. I usually boat @ 3600' altitude with a medium full boat. That said, 2 times in a year I will spend a week at high altitude (6K+') in which case I can leverage high altitude impellers to increase my top end performance.

So I have my original set of impellers that were re-pitched for high altitude (instead of for sea level). And now (when they are delivered) impellers for 3600' altitude.

The difference is quite a bit, usually, when you're not at sea level. This is the same thing I/O's and V-drive's do when they get different prop's. Gotta be able to turn the screw at the right rate for the fuel burn ratio of oxygen.

 

[MikeyL]

Thank you, @sysinu I, and I feel sure there are others, did not know this, and some NEED to know this.
Much appreciated, Mikey Lulejian - Lake Oconee, GA

 

[Ronnie]

@sysinu , I'm glad I didn't try and respond for you as your response is much more detailed than anything I would have stated.

IMHO, repitching the impellers is the single most effective way to improve performance on a jet boat. Replacing them with aftermarket units can be expensive ($800ish for me) so repitching the stock units (I think impros charges less than $100 per) may be the way to go especially if you boat at the same elevation most or all of the time. The down side being that repitching the impellers incorrectly is one of the quickest ways to performance loss so find someone who knows what they are doing.

I was gong to buy off the shelf impellers that others have tried with some success. Rather than sell me different models (port and starboard) impros recommended, based on previous experience, that I buy the same model solas and have them repitched. This should improve the low end acceleration, decrease any cavitation I have with the stock units yet keep them in synch rpm wise through the throttle range. That is the theory anyway, I'm looking forward to testing it out.