Yamaha HPDI gearcase mod..

SHIVERS · **Joined:** April 21st, 2012, 1:57 am **Posts:** 411

last night I started prepping my xr6 case for the Kit I picked up from Paul a couple weeks ago!the shop has been full of open motors,so the grinding and sanding work was on a back shelf for a while!
I really enjoy doing this stuff now that I don't do it all week long! well I haven't got to the sanding part,that sucks!
drilling holes is easy, they always end up being holes and they stay where you put them!painting is my nemisis,I put it on and it usually leaves shortly afterwards!

OneCycle · **Posted:** June 3rd, 2013, 9:27 pm

bump for jordan...

BoomerMuskoka · **Posted:** June 3rd, 2013, 10:49 pm

SHIVERS wrote:

well I haven't got to the sanding part,that sucks!
drilling holes is easy, they always end up being holes and they stay where you put them!painting is my nemisis,I put it on and it usually leaves shortly afterwards!

i know how that feels. :lol:

allstock · **Joined:** August 30th, 2012, 11:21 am **Posts:** 325

I'm dragging this fine piece of technical writing back up again because I'm going to give this a go this week, but I have a couple of questions. Do you feel that four holes is necessary, or would two be enough? My ox66 case had a bob's cone on it but only had two holes under the bullet, made great water pressure. Did you epoxy shut the existing pick up screens, or leave them open? The hpdi case certainly runs out of water psi sooner than a coned case!
Thanks in advance, Mike.

DoktorC · **Posted:** June 1st, 2014, 8:25 pm

I think 2 holes is on the edge of fine. Jordan only drilled two holes and would sometimes get a buzzer at idle. Mine has 4 and it's too much almost. It really makes a lot of pressure at speed.

Yes..you must plug the stock screens and make sure to trim the insides so your new holes aren't blocked.

allstock · **Joined:** August 30th, 2012, 11:21 am **Posts:** 325

DoktorC wrote:

I think 2 holes is on the edge of fine. Jordan only drilled two holes and would sometimes get a buzzer at idle. Mine has 4 and it's too much almost. It really makes a lot of pressure at speed.

Yes..you must plug the stock screens and make sure to trim the insides so your new holes aren't blocked.

Thanks Doc, as an experiment I'll drill two holes and just leave the bottom half of the screen open, ( I epoxied the top half shut last year). I give that a try and post the results, I can always change it if it doesn't work out!
Thanks again, Mike.

dubber · **Posted:** June 2nd, 2014, 9:53 pm

What about drilling 3 holes? Other than you would be doinked if you needed a 4th it wouldn't be symmetrical.

beavertonae-21 · **Posted:** June 3rd, 2014, 1:01 pm

Could always start with two smaller holes on the outside .

Steve

allstock · **Joined:** August 30th, 2012, 11:21 am **Posts:** 325

beavertonae-21 wrote:

Could always start with two smaller holes on the outside .

Steve

That's the plan! hopefully will have it ready for the weekend!

wildcatt · **Joined:** April 29th, 2012, 7:26 pm **Posts:** 503

I don't know about the HDPI cases, but the last few cones I've done, I've left the side intakes stock. One was a Yamaha, and the other an OMC. Both cases had no problem keeping water pressure when surfacing. I had the backup intake on the sides in case I ran into weeds etc.
My other plan was to just block off the side intake screens, then I could pull them off for draining etc. I never needed to do it though.

Just my 2 cents

HPBCANADA.COM

Yamaha HPDI gearcase mod..

Who is online