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Krazymaan
06-19-2016, 09:34 AM
I am having that water squirting out of my seam between the lower unit and the mid section that OMC's sometimes seem to get and I am trying to verify my lower unit. Once again as usual, I own a part that I can't properly ID.

This lower unit is on my 1988 200 XP but with apparently a 1987 Johnson 200GT powerhead.
The lower unit has 4 hole water intake. Does dont have an external screen, its inside. But it does not have the six holes above the cavitation plate, it has two slots and the tail end of the cavitation plate is tapered, like v shaped, not cut square. Plus my keg isn't quite shaped like the photos on the OMC website where you would ID your lower unit by year, shape, size and motor. There is a land and sea nose cone on it and they filled the low water pickup intake ports and are still using the 4 intake ports so don't judge what it is by the nose cone. Under the nose cone it goes straight up, no crescent no nothing, just straight.
To me it looks just like the 78-98 V4 90 degree except i have 2 slots, not 6 holes
It also looks similar to the large gear case 79-06 except i don't have an external screen pickup.
So do you think I have another frankenstein part for my collection or is there another lower unit I don't know about?
The bolt on oval plate has three large holes behind it. I think that was a modification. We don't need to ID that.
One more thing is the exhaust bellow/pipe on the inside with the thick rubber seal around it. When looking at all the photos online. They all seem to be about 12" long or so. Mine is defiantly only 3" tall.

Krazymaan
06-19-2016, 10:04 AM
I can find a 3 hole with slots and a 4 hole with holes but not a 4 hole with slots. But i can't seem to find this exact one.
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Hows this for a crazy trim tab. I don't know it it hurts me or helps me.
346488

BarryStrawn
06-19-2016, 10:34 AM
That is the 1988 setup.

Krazymaan
06-19-2016, 10:44 AM
That is the 1988 setup.

Thanks for the help. You would think this would be in the book somewhere

racer
06-19-2016, 09:36 PM
The longer exhaust adapter is for 25 inch shaft length. Later 25 inch engines used external screens. Skeg is worn at the front bottom edge. Like Barry said 88 up to mid 90'S. Leaking at the seem is most likely exit water.

Krazymaan
06-19-2016, 10:05 PM
Thanks for the info. I will always remember it.

Krazymaan
06-19-2016, 10:08 PM
Well maybe while I'm waiting on my Service Manual to show up I can clear out the lower water pickups, take the plug out of the top of the nose cone, plug the side intakes and make the new tube go somewhere. Not sure where, but I seen pics on here somewhere. I'll have to look that one up too. Can't be that hard right?

PARKER RABE
06-20-2016, 01:01 AM
i have a 86 150 johnson and its leaking exhaust down the mid, crazy like black tar?any ideas?

PARKER RABE
06-20-2016, 01:06 AM
thoight it as leaking at the powerhead but it looks like the motor mounts!

racer
06-20-2016, 07:16 AM
Parker does the leak start above the adapter plate? If so powerhead gasket or lower main seal but that would be more oil like. Below adapter loose powerhead bolts. I would also check the exhaust plate between the cylinders.

PARKER RABE
06-20-2016, 08:58 AM
cant really tell, looks like its comming from the mounts , i took the skirt off and didnt really see anything , its running down the front of the can, its all black everytime i run it.

racer
06-20-2016, 10:27 AM
Sounds like lower main is leaking.

PARKER RABE
06-20-2016, 10:37 AM
man there aint no way that salted up power head is comming off there. will it hurt it to run it like that? thing runs perfect.

PARKER RABE
06-20-2016, 10:40 AM
Great little motor

PARKER RABE
06-20-2016, 10:41 AM
sorry for the sideways pic

PARKER RABE
06-20-2016, 10:42 AM
can someone help me straitin it?

PARKER RABE
06-20-2016, 10:44 AM
its all clean in that pic, after i idle it around for an hour that slug is running down the can, nasty black sshhit

PARKER RABE
06-20-2016, 10:45 AM
wish i had a pic of it it even drips down on the zinc on the lowerunit and comes out the vent hole in the lowerunit.

racer
06-20-2016, 02:14 PM
You might try turning it to the side and looking at the lower main seal while it is running. If it idles good and you don't think it will come off I would run it.

PARKER RABE
06-20-2016, 05:26 PM
i do brother , runs great

Krazymaan
06-27-2016, 08:51 AM
Maybe you just need to drive faster then those vertical black sheep stripes will be horizontal and look way cooler.