conversion from omc lower to merc

[SUPERSTOKER]

ive done it again...pinion gear plus drive shaft. dont know if i can even get parts but am wondering if a sportmaster is possible . any help?

[Mr.Rude]

Taylor make these plates, driveshaft will require a few mods too.

http://www.madefi.com/midsec.htm

[Smoking Joe]

Superstoker, what engine are you currently running???

[SUPERSTOKER]

Superstoker, what engine are you currently running???
89 300xp, 4ltr

[rockman69]

Im on my third season with my lower on a fingerported 4L. Good oil and I NEVER shift while running. Havent had any problems.

Of course, a "season" here in Illinois could be only three months!

[SUPERSTOKER]

Im on my third season with my lower on a fingerported 4L. Good oil and I NEVER shift while running. Havent had any problems.

Of comyurse, a "season" here in Illinois could be only three months!

my last one got me seven yrs here in new york. think surfacing is the problem along with bad design

[racer]

I have been installing the new sle unit from a 300 e-tec with good luck. Drive shaft is no problem but shift shaft needs to be cut and rethreaded. Draw back is gear ratio at 1.85 instead of 1.75

[SUPERSTOKER]

[QUOTE=racer;2181268]I have been installing the new sle unit from a 300 e-tec with good luck. Drive shaft is no problem but shift shaft needs to be cut and rethreaded. Draw back is gear ratio at 1.85 instead of 1.75[/QUOTEthanks
thanks 4 the info, how about bolting up...everything the same? waterpump?]

[racer]

You need to notch the exhaust, bolt pattern is the same. Drive shaft is for a 2 piece x flow not your current engine.

[STV_Keith]

If you really want to do the Merc swap, it's a bit of work. I've done it (twice) on my Scarab. CLE's on V8's. Check out this thread: http://www.screamandfly.com/showthread.php?117768-Is-anyone-currently-running-a-Merc-Sporty-on-a-V8

My local prop guy, Kevin Taylor at R&R Prop Shop built my adapter plate in his CNC. He also cut the driveshafts, resplined them, assembled the gearcases and cut the reliefs in the gearcase to clear the socket head cap screws that attach the adapter to the mid. You could basically send him your gearcase an a driveshaft from a Merc that is 5" longer than what you need, and he can do the rest. As Al said, the CLE's are 1.87 ratio vs. 1.76 for the stock OMC's, so I had to go up 2" of pitch. I now run 26 Bravos with vent holes (Kevin cut those too).

You will still need to extend the water tube about 1", rig up your own shifter rod (OMC push/pulls, Merc twists), and decide if the Merc water pump will do for you. My motors will not make pressure at idle, and since the V8's water cavity is so big, they will get hot before filling the blocks if you idle for long. I ended up with secondary electric water pumps in the boat, thru-hull fittings and a check valve, to pump water into the cold water section of the exhaust adapter to help feed the motors at idle. That works good, other than they sometimes "air lock" and I have to break the connection to get them to flow water again.