1987 175 HP ( V-6) ByPass Cover Removal

[KRH1326]

Hi All,
Am working on my 1987 Evinrude 175 HP. I need to remove the bypass cover. I have the engine stripped down to the cover, at this point. Do I HAVE to remove the entire power head? I VERY much just wish to remove the cover as is, and get on with my mission.

I can see the smaller bolts around the perimeter of the cover, and the larger bolts, near the bearings, as well as the bolts on the rubber motor mounts. Are there any that need to be removed from below? does the power head need to be removed to access those, if any?

 

[emdsapmgr]

Are you working from a factory service manual? Not sure just what your disassembly plans are. Yes, you can remove all 6 of the bypass covers without removing the powerhead. Each one has 4 1/4" bolts securing each cover. The reason I'm wondering is that you refer to the "bypass cover" as a singular item, when in fact there is one for each cylinder. I am thinking that you are actually referring to the "exhaust cover" at the rear of the powerhead. Please correct my interpretation if my understanding is incorrect. That cover (both inner and outer) can also be removed without pulling the powerhead. If you want to re-install the exhaust covers on that engine, without removing the powerhead-now that will likely be a problem. The factory service manual will instruct you to have the base of the powerhead absolutely parallel to the base of the inner exhaust manifold when it is re-bolted in place. That's almost impossible to do without having the powerhead on a bench to check for flatness with a straightedge when the inner manifold is reattached. It must be parallel so that the powerhead is clamped to the exhaust adapter evenly, and moreso that the exhaust o-ring has the proper clamp load so that it does not leak exhaust gas at that joint. A skilled technician can remove and re-install the exhaust manifolds without removing the powerhead from the exhaust adapter.

 

[KRH1326]

I am working with a Clymer and Seloc manuals (which are terrible, I just have not found an authentic OMC manual for my model year)
The short of it, is that I need to expose the crank and rod caps. The aftermarket books are using different terminology than the OMC book for a later model, that I am able to look at.

I have the flywheel, timing base and upper cap off. I have the heads off, as well as the carbs, starter, and the intake manifold ( that had all of the reed boxes mounted on the inside. The piece I now need to remove, is what the aftermarket books call the bypass cover. It has the passages in it that feed fuel/air to each piston. I think it is more like a case half, than a cover. The upper cap had bolts that caught this and the block, so would the lower cap bolts need to be removed too.

 

[emdsapmgr]

You can get original factory manuals for your specific engine from the original publisher, Ken Cook Co. You can call them direct in Milwaukee (414-466-6060), or order them online from their website: outboardbooks.com. These are the only books to be working from. Still not sure just which part you are describing that you need to remove. Once you get the intake off, you are basically left with the two block halves. In order to separate these two halves, you will have to remove the powerhead from the midsection. Lay the block on it's back with the intake side up. You'll have to remove the lower crank cover (crankcase head) from the bottom of the block. Once you separate the two block halves, the crank is exposed. You may find it helpful to refer to the factory exploded parts diagrams for your engine. Checkout this factory website: epc.brp.com. You see how all the parts go together and can verify your part terminology with the parts lists.

 

[KRH1326]

That is what I believe it is. The intake side case half. Ok. Thanks for the info.