Water intake screen quest

[travis g]

i have a 1988 90hp Merc. I just bought the rig and the motor doesnt have any screens in the intake holes. I have been tod that they cant be installed because it neveer had them. A man told me that i could get some stainless mesh/screen and bond it to the outside of the foot with 3m 5200 bonding agent but a dealer told me that was a bad idea. Anyone have any advice? I cant keep sucking weeds and junk into the impellor or im gonna have bigger probs.

 

[travis g]

Re: Water intake screen quest

ttt

 

[thasatelliteguy]

Re: Water intake screen quest

I am having the same problem. I have a cabin out in shallow water where at low tide I drag on oyster reef. I keep getting oyster bits hung up in my poppet valve, causing it to open late and cause a mid-throttle overheat. Since the poppet is kind of a pain to get to on my motor, I need a way to stop this. I think I'm gonna try something along the lines of wrapping the lower unit with a couple wraps of window screen or something.

 

[Chris1956]

Re: Water intake screen quest

Travis, I never saw any intake screens on those inline mercs. You can fabricate and install them if you want, but I would be concerned about the screens causing water restriction causing overheating.

You would need to drop the gearcase, and remove the waterpump base. That will give access to the top of the water intake interior. You will need some rigid screening that fits the cavity. I am not sure how you could clean the screen, from the exterior.

Maybe a better idea would be to install some screening on the exterior of the gearcase, maybe with some marine-tex to fasten it.


A third idea is to cut away the aluminium that has the water intake holes, and replace the holes with a prefab screen, likely trapaziodal shaped. You would need a way to hold it in place, likely some sort of thru bolt. Take a look as a Mercruiser Alpha I gearcase. They have removable water intake covers. It might give you some ideas.