Gas lower units

[Rick Larocque]

Contemplating building an ML gas tunnel. What would be the outboard drive of choice that you guys are using? Any reviews on different drives would be greatly appreciated. Contact info for these drives would really help out also.

Thanks in advance

Rick

 

[David Santistevan]

I am using the Arrowshark lower that is a geared drive. I chose this because it seemed that all of the shaft drives were having a lot of trouble. I have gotten mine but really not tested it yet. It appears to be a very high quality unit.

http://www.arrowshark.com

Dave

 

[Rick Larocque]

over 100 views and 1 reply (thanks by the way). HMMMM. makes it hard to get good info for a new class to run.

Rick

 

[dion smith]

I think everyone wants to know the same thing, the lower I'm using is now unavailable, your mains ones now are the lawless, arrow shark and insane make one for their hull. There are the German vp geared lowers also. Join the 1/4 scale outboard group on Facebook and see what you find in there. There are a few more around that are made on request. Good luck

 

[Rick Larocque]

thank you

 

[Bruce Soberg]

I will be running a Joe Calogero Leg on my tunnel I have herd good stuff on them

 

[RonShaw]

Rick,

Look at the thread about Gas Tunnels increasing in popularity and you will find some helpful information there as well. Dion is right. The 1/4 scale outboard group on Facebook will give you some insight as to what others are doing around the world. Congrats as you have picked one of the newest classes and all of us are still learning!!...

 

[Rick Larocque]

Thanks for the info. Lots of research to do before deciding. Every bit of info helps.

Rick

 

[user 16820]

Hi Guys,

I have completed my first GX480 kit purchase from Mike with an Arrow Shark lower. First thing i must say is if you go this route there is much room for improvement on the lower. Namely the bushing, and grub screws of the pivot/steering. There is only one screw in the bottom end to hold the shaft in place. This is disastrous as the bush finally wears out in the Aluminium due to vibration and torque.After about an hour of racing i checked the boat only to find that i would have lost the motor within a few minutes if i did not stop. The water cooling pick-up also has to be modified as there is too little water entering the motor/cooling.

After replacing, modifying bushing, and fitting grub screws top and bottom it has turned out to be an Absolute pleasure! Done about 5 hours testing now.(not much), but stripped lower to find gears etc in perfect order.

Performance is very good and surprising.

I will get Wennie Bester who is an perfectionist at what he does, to check for himself, test the boat, and come back with more comments by end of week.

 

[Rick Larocque]

Donald

Thank you for this review. How did you fix the cooling situation? What are you running for a motor? Would love to see some video of this combo.

Rick

 

[RonShaw]

Donald,

This is the first feedback I have seen on the Arrowshark lower. Looks promising. Can you share details and pics of the mods you did on the pivot pin area and water pick-up? Would appreciate the tips as several of us are considering running this lower. Thanks.

 

[user 16820]

Hi Guys,

I increased the OD of brass/copper sleeve,knurled and press fitted it. Also fitted top and lower grub screws ,which i increased to 6mm OD. Ideally this should also have a grease nipple fitted.(will be doing this!)The water pick-up i re drilled with an angled hole facing forward.

Even though the gears look fine for wear i have ceramic coated a set for testing.

Also for what its worth i have designed a new tunnel hull which i will be manufacturing from Carbon Fibre. This will be pressure formed one piece unit. Will be available early January.

My cowl as per profile picture, is also being upgraded.

I am running a stock PUM 300, and find Mikes GX 480 fantastic! Did make some minor hull changes.

 

[rumrunner]

Any pictures of your new boat you designed?

 

[user 16820]

Hi Shane,

Will have pictures available end December. Moulds being build as we speak.

 

[rumrunner]

Thanks Donald , will be looking forward to seeing it.

 

[user 16820]

Hi All,

Warning re design on Arrow Shark final drive end.

My boat has been on the shelf for some 8 days now, and have just discovered that the bearing and thrust bearing before the Propeller has rusted solid!

Really stupid of me not to have noticed this flaw! This bearing is submersed in water and has no seal/protection.Either one has to grease before and after every time it is used,or find a way of sealing it from the water.

Any advise on this will be appreciated.

 

[Rick Larocque]

What about the MHZ geared drives? Anyone running these?

Rick

 

[Len Reeves]

Hi All,

Warning re design on Arrow Shark final drive end.

My boat has been on the shelf for some 8 days now, and have just discovered that the bearing and thrust bearing before the Propeller has rusted solid!

Really stupid of me not to have noticed this flaw! This bearing is submersed in water and has no seal/protection.Either one has to grease before and after every time it is used,or find a way of sealing it from the water.

Any advise on this will be appreciated.

Hi Donald,

Also watch out for the thrust bearing the brass cage can't be very good as the balls can fall out and you might not notice they have fallen out ! lost two of them also found out about the bearing not being sealed but mine did not rust up.

Kind Regards,

Len.