1975 9.9hp where is the water drain for the exhaust housing?

[jmendoza]

My exhaust housing is not draining. Is the notch on the bottom of the impeller pump housing (faces aft, below water tube, notch is between pump housing and stainless plate) the drain?
Engine runs fine, pumps water, cools properly, exhaust housing is not draining. Recently overhauled lower unit and power head.
Any help is appreciated, thanks in advance.
Jay

 

[F_R]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

OOOPS, Deleting my reply. I had 9.5 hp on the brain.

 

[Vic.S]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

There is a drain for the cavity within the lower unit

1/8" on older models 1/4" on newer ones

 

[jmendoza]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

Thanks for the picture of the gearcase drain. That drain lets the water out of the gearcase, and the exhaust housing above it. To make this more clear, mine is draining, but only for a little while, thus only the gearcase is draining as normally the exhaust housing is full of water when the engine is running and passes through somewhere to the gearcase to drain once the engine is stopped, which takes a few minutes. Mine however drains too quickly, and I can still hear water in the exhaust housing(mid section) with the engine out of the water.
So, the gear case drain is not plugged, it's good, but there must be a bleed hole somewhere between the gear case, and exhaust housing that lets it drain after the engine is stopped, and mine is plugged some how. I was looking for someone who knew exactly where the exhaust housing drain hole into the lower unit is located so I can check it once the lower unit is off.

In my post above, I was wondering if the little notch on the bottom rear of the water pump housing is the drain hole for the exhaust housing water to drain into the lower unit.

Any assistance is very much appreciated, thanks in advance, and to those who have already replied, I appreciate your time and trouble too, Thanks! Jay.

 

[jmendoza]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

Guess this must be a pretty tough one, as nobody here seems to know how the exhaust housing water gets into the gearcase drain area?? It stumped me, so I guess that means it's stumped us all? Can't be true, I know one of you guys has to know, or has seen this problem.....TIA

Jay

 

[Chinewalker]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

Not sure how that can be - the housing is more or less open to the unit. I'd drop the leg and see if something is plugged up with critter mess...

 

[Vic.S]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

In the picture below the four holes indicated by a red arrow is where the water will exit.

 

[jmendoza]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

Thanks Vic and Chinewalker. It must be some mess in there, it's holding water without leaking. I'll take my camera with me up to the cabins this weekend and take pictures of what I find.

 

[jmendoza]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

Ok, see that big grommet on the left? Well guess what, on the 1974-76 models it's so tall that it seals against the bottom of the exhaust housing, and so the water can not drain past the oversize hole the copper water tube passes through. The original water tube grommet is shorter and therefore it cannot reach the exhaust housing casting, allowing the housing to drain through the gap in the hole the water tube goes through. I resolved this issue by cutting a notch in the top of the grommet so the water in the exhaust housing can drain into the lower unit. Thus the large water tube grommet is for later models and will cause problems in the earlier versions not designed for it. The problem is the exhaust housing will stay full of water, and possibly crack if it freezes.

 

[OptsyEagle]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

I wonder if that grommet material is the black rubber stuff I keep finding in my exit holes (where the red arrow is on the picture a few posts up).

I've owned two of these motors (a 1975 9.9Hp and a 1976 15Hp) and they both have this black material that shows up in that cavity. The 1975 still seems to pump water fine. I'm still working on getting some spark on the 1976 to say how it pumps water.

Should loss of those grommets cause some problems?

 

[jmendoza]

Re: 1975 9.9hp where is the water drain for the exhaust housing?

That is typically the upper engine mounts that deteriorate and leave chunks of rubber in the hot water outlet holes above the cavitation plate, at least that was the problem with my 1975 9.9You will notice the engine shakes it's head a bit more than normal at idle due to the mounts going bad. You have to pull the power head to replace tnem, and that is a good time to replace the upper water tube grommet, crankcase head seal and o ring, upper drive shaft o ring, and engine to exhaust gasket as well. When you do that, it's also easier to drop the lower unit so you can get the copper water tube back into the water pump, so you may as well rebuild the pump with new seals and impeller while you are there.