OMC Cross Charge Mod questions

**Riverratt** · 12-19-2011, 04:29 PM

They will advance at least 4 degrees as the rpms increase

**rhickox** · 12-20-2011, 09:31 PM

Project 115 Crossflow almost finished!! will post pics when I get everything blended and like I want it.. Gonna see just how much power I can get out of this thing.. Making a one off intake plate to put some 2.4 merc carbs on it!!!

Along with all linkages that the 115 used...

**rhickox** · 12-22-2011, 10:41 PM

Not finished blending and polishing the cuts yet, but thought I would post a pic... Guess we will c how it works out. It might be a slow POS or it might be fast.. Never know till ya try.. It was a free mota and I enjoy experimenting..

I think it's gonna need a LOT of Fuel and Air..And A LOT of Exhaust opening also which I have started working on...

**evilrude 1** · 02-23-2012, 11:28 PM

Hey Rhickox how bout an up-date
Hows the grinding going ???????????
More pics !!!!!!!!!!!

**terry taylor** · 02-24-2012, 09:52 PM

Originally Posted by Forkin' Crazy

I've never had that happen on a crossflow.

Since you did all the porting work, maybe a couple size larger jets would be in order, at least to start with. You need to set your timing at 4500 RPM or so and under a load as Jeff mentioned.

Did it just stick, or did it burn off the corners of the defector then stick?

----------------Did freddie ever answer your last question thanks ?

**930turbo** · 03-29-2012, 01:32 PM

I finally got around to taking it apart.

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**terry taylor** · 03-29-2012, 07:38 PM

Jee I hate when that happens

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**Forkin' Crazy** · 03-30-2012, 12:18 PM

Originally Posted by terry taylor

----------------Did freddie ever answer your last question thanks ?

Not that I saw. The only motors I heard of that do that was with big bore carbs on loopers.

Hey 930, good think there are plenty of V4 parts around. How much is, or was your cranking compression?

**Freddie Webb** · 03-30-2012, 12:38 PM

Forkin' I sent you a pm.

**930turbo** · 03-30-2012, 06:18 PM

I didn't check the cranking compression. I should have. I'm steppping down to the '77 heads on the next build.

**evilrude 1** · 03-30-2012, 06:38 PM

I would check to see if you had any air leaks or gasket failure. I think you posted you were having lean sneeze issues.
You might also check your fuel pump I had the same problems with the engine falling on its face every once and a while. Put a new pump on it and problem solved.
Other things to make sure are "on the money" is timing and jetting (just stating the obvious)

Don't you just Love "trial and error"
I'll be doing the "tuning thing" later this summer my self with a 140 I'm building.

**930turbo** · 04-29-2012, 07:22 PM

Getting the new replacement piston coated for reassembly very soon. I'm also building a second powerhead with the same spec for my boat. I now have two square ported blocks with the scalloped transfers. Replacement throttle shafts in route as well to resolve the low-speed leanness issue.

**930turbo** · 07-14-2012, 08:02 PM

The motor is back together. I set the timing @ 25 degrees @ 5000. I also checked it at cranking speed and it's the same 25 degrees. The only time on it thus far is to set the timing under load. It has 152-156 compression. I hope this one doesn't melt down.