Water Intake Screen Replacement

[adamd1357]

I have a 1977 70 HP Johnson outboard that needs a new water intake screen. I broke out the brittle old one. I have the new part but can't seem to get it past the bearing housing. I have removed the 4 bolts holding the bearing housing in place but it won't seem to budge. I have tried putting screwdrivers under it to pry it off, but it won't release. Also, when I do get it loose, will oil spill out if I don't have the lower unit in the upright position?


Any guidance would be greatly appreciated!!!

 

[boobie]

Re: Water Intake Screen Replacement

Yes. Oil will not spill out in the upright position. Try a real sharp putty knife and after you get it off don't forget to replace the gasket.

 

[adamd1357]

Re: Water Intake Screen Replacement

Yes. Oil will not spill out in the upright position. Try a real sharp putty knife and after you get it off don't forget to replace the gasket.

I don't think I can get a putty knife down to where the housing meets the mating surface...


Do I need to replace the o ring between the housing and the shim or just the two oil retention o rings on top of the housing around the drive shaft?

 

[boobie]

Re: Water Intake Screen Replacement

I can't remember having to remove that hsg. The water pump, yes. Have you got the correct screen ??

 

[Bosunsmate]

Re: Water Intake Screen Replacement

Just lift off the backing plate under the pump, dont go any further down, the screen is in the back directly behind the Bearing housing (which you definitely dont remove).

If you have removed that housing you will need to replace those orings. You should get the water pump to metal base gasket too, its only $2

 

[adamd1357]

Re: Water Intake Screen Replacement

Hmm, I had to break the old screen apart to get it out.... I see that the part # for the 15" gearcase is different from the 20" gearcase. Believe it or not I have not measured the midsection to see which one it is. I just assumed the 20". This is a new boat/motor to me. I will feel like a schmuck but relieved if I have the wrong part and the new one slides right in!

 

[boobie]

Re: Water Intake Screen Replacement

What's your model # ??

 

[Bosunsmate]

Re: Water Intake Screen Replacement

If you cant provide the model number post a photo

 

[adamd1357]

Re: Water Intake Screen Replacement

Model # is 70EL77S. Which after some googling I think translates to 70HP, Electric Start, Long Shaft 20", 1977, Not sure what the S means, I think just a model run... Do I have all this correct?

Which means that I think I have the right screen... 0314175 according to marineengine.com (Where I bought it)and the Johnson Evinrude parts website.

 

[F_R]

Re: Water Intake Screen Replacement

Well now, some models do require removing the drive shaft bearing housing to install that screen. Sorry, I don't remember which ones, but it would appear that yours is one of them.

In any case, there is nothing holding it in there except an o-ring. Unless it is all corroded in from salt water or something.

BTW, the S indicates any mid-year changes....IF there were any. Otherwise, it means nothing.

 

[adamd1357]

Re: Water Intake Screen Replacement

Mine appears to be corroded in place, it doesn't want to budge at all... So I have a decision to make. Do I continue to try to remove the bearing housing (suggestions?)or do I try to modify the intake screen so I can flex it in past the housing?

Also, Is it possible to replace the oil retaining o-rings on top of the housing without removing the housing? I would like to do that while I am here. Is that the same oil as the lower unit oil that I replace every year or is it a separate sealed oil bath?

 

[racerone]

Re: Water Intake Screen Replacement

Run a 5/16-NC tap into 2 of the bolt holes in the bearing housing.---Then make up a plate / adapter and use bolts or studs to pull the bearing housing out.

 

[F_R]

Re: Water Intake Screen Replacement

I can't imagine having any success with modifying the screen. If I remember correctly, the bearing housing overhangs the actual gearcase casting, which is why it is in the way. As a last resort, I'd suggest grinding the overhang away. Got a rotary cutter for a drill?

Yes, same oil as below.

It probably is possible to dig the seals out, but once you begin, you are committed. Better use the if it ain't broke, don't fix it approach.

 

[adamd1357]

Re: Water Intake Screen Replacement

Here are some pictures. The second photo with the scratch line is where the screen is hitting.

Cant really see it, but there appears to be just a tiny bit of oil around the seal on the drive shaft. Not sure if it is just pb blaster that I sprayed in there and won't come out of the groove with a paper towel. I will have to do some more thinking/tinkering on that. I think I will try cutting the middle plate from the intake screen rather than cutting into the housing, much cheaper to replace...

 

[racerone]

Re: Water Intake Screen Replacement

It is safe to cut the needed amout off the bearing housing !-------Use a rotary file if you are going that way.

 

[classiccat]

Re: Water Intake Screen Replacement

I did a full reseal of my '75 70Hp this summer and recall having a heck of a time getting out the d/s bearing housing on mine as well.

I ended up using 2 paint-can openers to get leverage under it...making sure the LU is secured to the bench. I remember wondering if vacuum has something to do with it so I drained the oil & kept the drain plug off.

when it's off, you should replace the back-to-back driveshaft seals as well as the bearing housing o-ring.

 

[classiccat]

Re: Water Intake Screen Replacement

I'd be careful about filing-off the lip of that housing...it really aids in the housing removal.

 

[adamd1357]

Re: Water Intake Screen Replacement

How about the shims that mate with the o-ring under the bearing housing, do those need to be replaced as well? Or as long as they are in good shape just clean and re-use?

Thanks everyone for your help!

 

[adamd1357]

Re: Water Intake Screen Replacement

I will also crack open the upper vent hole to release any vacuum

 

[adamd1357]

Re: Water Intake Screen Replacement

Any harm in heating up the housing with a torch if I were to plan on replacing the o-ring and back to back oil seals anyway?