'96 Johnson 225 Rebuild

[gw204]

I recently picked up a '76 Formula 233 that I am going to convert from twin 140 Mercruisers to a single outboard on a bracket, a '96 225 Johnson to be specific.

http://img.photobucket.com/albums/v508/gw204/Boat%20Pics/Formula%20233/IMG_8494.jpg

The motor, which was also required recently, has been in storage for the past 2 years and is in need of a rebuild as it has low compression in the no. 2 cylinder. The seller told me that other than performing a compression test, no other diagnostics were done and the motor was simply replaced. From the looks of the head, it seems the piston ring pin (sorry if that isn't the correct terminology) that I have read about let go...

http://img.photobucket.com/albums/v508/gw204/Boat%20Pics/Formula%20233/IMG_8500.jpg


Being that I only have $300 invested in this engine so far, I would like to try the rebuild myself (it will be my first). So, I have been trying to find information regarding simple ways to get a little extra power w/out sacrificing reliability. I'm not looking to do anything fancy as this motor will spend most of it's time at 1000 or less and from 4000 to 4500 running on pump gas.

Unfortunately, I am not coming across much other than CCM reeds, pro or vertex pistons and cutting the heads. So, I was hoping you guys could give me some tips.

I do have a line on a set of '96 175 heads. Would those bolt up and/or do anything for me?

Thanks.

Brian

[flabum1017]

Personally, I think you will need two of thosemotors for that boat.... As for more power.... call Monty, they can point you in the right direction for porting and such.........

[faztbullet]

Have the water cooling mod's done to block... and find its twin

[oldschoolltv]

My long lost twin, just kidding, it would be better to leave it stock and run twins, on a big heavy boat you do not want a moddified looper, just my 2 cents Matt

[gw204]

Thanks guys.

About the twins... I'm really not interested in running a pair on this boat right away. I think with the proper setup, it will easily meet my needs. I've seen performance reports from other 233 owners and those indicate top speeds in the low to upper 40s and cruise in the mid to uppers 20s with the single 225/250. That's plenty fast for what I intend to use the boat for.

If there are risks associated with pushing a heavy boat on a modded motor, then I'll just stick with a stock rebuild. Is that what you guys would recommend for my situation?

[thehermit]

gw / S&F,

long time lurker 1st time poster. I have the same motor (yr 2000) pushing my 23 SeaCraft. I will follow this thread with intrest as I am considering a rebuild/ refresh bore over for the winter to fix some leak down on #4.

http://www.mar-fab.com/MarFab_Tech_Bulletins_D9579.pdf is this the cooling mod fazst? I thought that I had read here that they fixed this somewhere around 1998 so is it still the way to go on the 1996 block?


gw....what do you plan to bore too? Also I am very intrested in what you replace/re-use. Glad to follow this thread and good luck!

[ChrisCarsonMarine]

Cut heads 030,clean up flashings and ridges all over in the block and intake,match up the intake ports in the bloch[aluminum] to march the steel sleeves[no porting the sleeves],add our sport reeds,run mid grade or premium fuel,prop to 58-6000 rpm.you should see about 15 hp gain and a much stronger idle,acceleration,chris

[gw204]

gw....what do you plan to bore too? Also I am very intrested in what you replace/re-use. Glad to follow this thread and good luck!

I haven't gotten that far yet. The motor is still fully assembled with the exception of the damaged head. My gut tells me to do the minimum it takes, but I will probably leave that up to the machine shop that does the work though.

[gw204]

Cut heads 030,clean up flashings and ridges all over in the block and intake,match up the intake ports in the bloch[aluminum] to march the steel sleeves[no porting the sleeves],add our sport reeds,run mid grade or premium fuel,prop to 58-6000 rpm.you should see about 15 hp gain and a much stronger idle,acceleration,chris

Thanks Chris. Do you think the head pictured above is usable or should I look for a replacement?

[power of one]

GW i would run 2 of those mate my 233 had a single 250 the hull fully rebuilt with klegecell foam core internals and i found her to be a pig when fully loaded with 350 L of fuel 50L of water 4 guys and dive gear 17 stainless prop low 20 knot cruise at 4200 mark from memory sluggish out of the hole very uynstable at rest due to lightning the hull up and no weight on the tranny flood chamber sorted that issue out. Ihave rebuilt 7 of these hulls for past clients i dont like pods or shaft drive application messes with LCG and the convex chine plays a big part to how these hulls run i wish i put apair of rebuilt v6,s on instead of a new 250 216543 pm me iyou need more info :thumbsup:

[ChrisCarsonMarine]

Gw,the head will have very few flaws left after the 030 cut,can't say for sure but I think it will be fine,we can supply necessary parts and or machine work,chris

[thehermit]

Gw,the head will have very few flaws left after the 030 cut,can't say for sure but I think it will be fine,we can supply necessary parts and or machine work,chris

For my own benefit or gw's....other than fixing the damage on the head that gw shows....what benefit is there to cutting the head by.030 ??? Forgive the rookie question.

[ChrisCarsonMarine]

The 030 cut will raise the compression by about 10 lbs /in2,noticable stronger idle and acceleration,chris

[thehermit]

The 030 cut will raise the compression by about 10 lbs /in2,noticable stronger idle and acceleration,chris

sounds nice....what does it do to fuel burn?