3cyl omc technical question

[Hunter]

....looking for advice from anyone who has successfully cooled the 3 cyl omc with a flow-thru system rather than an impellor water pump. Where do you introduce water and where do you discharge it.
Hunter III

[T Chance]

I run Pro, but when I came back into racing after 16 years out of the sport I had a 3-cyl OMC Super E built (tested it but never raced it). I had it on a Konig gearcase and Konig tower. The water was forced by speed into the holes of the front of the Konig unit, up a hose to and in and out of the motor same as if the lower unit had an impeller.

Tim Chance, Saint Louis, MO Y-200

[hpick86n]

3 cyl OMC cooling

The 3 cyl OMC has very high volume water jackets. With that in mind it takes a long time filling the block when planing off.So there should not be any large water dumps until the top of the block. For some reason the middle cylinder on those motors always runs lean and hot. I cant tell you why ,maybe the siamese exhaust on 1 and 2 . Also be shore to use the O.E.M.head gasket.

[form-e one]

hunter im me will tell ya,,, bin there done it...

[Hunter]

....of the 5 motors I cooked this season, all involved the destruction of the top piston. I am curious about what happens when we bolt on the flat exhaust manifold. It alters the cooling loop from the fishing motor configuration. How much of the various baffles under the manifold should be relieved, drilled, or removed. By comparison,my son runs with an impellor and has no trouble. My much loved TIETZE mid-section does not have enough material at the bottom to mill out a space for an impellor.

[thetrailergod]

whats you # I ll call ya. I know exactly what is happening

[mercguy]

....of the 5 motors I cooked this season, all involved the destruction of the top piston. I am curious about what happens when we bolt on the flat exhaust manifold. It alters the cooling loop from the fishing motor configuration. How much of the various baffles under the manifold should be relieved, drilled, or removed. By comparison,my son runs with an impellor and has no trouble. My much loved TIETZE mid-section does not have enough material at the bottom to mill out a space for an impellor.

Hunter, I had a spacer machined for an impeller (50hp Merc impeller) that fits between the bottom of my Tietze tower and the Bass lower unit...........adds about 3/4" of additional height......I can provide pics, if needed..

[94H]

[ATTACH]32763[/ATTACH]

[bh/]

,,a spacer machined for an impeller (50hp Merc impeller) that fits between the bottom of my Tietze tower and the Bass lower unit...........adds about 3/4" of additional height..

-this is a older Bayer adapter that is fitted with a impeller.
Simple, works well, adds ~1" to the height.

The ZAK adapter/plate is about 1-1/2" thick, and could easily be machined for a pump impeller.
That is the only reason I see why it is that thick.
One's stub shaft may need to be lengthened to extend thru the adapter .