1976 Johnson 9.9 Upper water tube grommet

[sailfish]

I'm replacing the upper water grommet on the pweorhead fo my 1976 Johnson 9.9 outboard and have conflicting instructions regarding how to install it. One guide says to put the rubber grommet halfway over the top flange of the copper tube (there is an internal groove in the grommet so this is believable) while another source says to install the grommet under the flange, so the flange sits on top of the grommet.

The mating surface, on the underside of the powerhead, is oblong and the grommet does not fit inside of it so I doubt the halfway strategy is correct yet if the grommet is fully under the flange then it is only compression and the gasket holding the tube to the powerhead, which does not seem ideal either.

Any help would be very appreciated!

 

[Vic.S]

Re: 1976 Johnson 9.9 Upper water tube grommet

With the flange located in the groove in the grommet is how its fitted in my 6hp.

It's got to hold the water tube, its got to make a water tight seal round it and it must not allow the copper tube to touch the aluminum.

Some engines I think have a grommet that fits below the flange but they have a separate spacer/retainer above it.

Id say that if you have the correct grommet for the model and it has an internal groove then that is designed to fit over the flange.

 

[sailfish]

Re: 1976 Johnson 9.9 Upper water tube grommet

Thanks Vic, I appreciate the reply.

If I put the flange in the groove it becomes very bulbous and does not want to seat properly in the exhaust tube or where it mates to the powerhead. I am hesitant to force it too much but thought that if it were to go this way perhaps the part sticking up toward the powerhead would compress around the hole in the powerhead providing a good seal. If this is wrong though I may crack the exhaust housing so want to be sure I am doing the right thing before applying too much force.

Thanks again....

 

[mikesea]

Re: 1976 Johnson 9.9 Upper water tube grommet

I seem to remember the grommet fits over the tube as the first instruction says.The problem that occurs in that location is a buildup of salt and or corrosion,that is what cuts off the flow,.Be certain all the corrision /buildup is removed,that may be part of the ill fit your experiencing. Heres a link to a guy that has alot of info on your eng. it should come up showing the grommet install
http://www.sschapterpsa.com/ramblings/water_circulation.htm

 

[dazk14]

Re: 1976 Johnson 9.9 Upper water tube grommet

I have seen them both ways. I have a late 70's sitting in the shop and that uses the mid-point grommet . As mentioned clean the recess and put a little spit on it and it'll go into the recess.

There is a gasket that seals that opening to the block, so you can also have the flair at the top. The trick here is to straighten the tube to elongate it a bit (~1/4') maintaining the insertion depth in to water pump grommet.

The latter was used to avoid the dreaded grommet swelling/deforming blocking water flow.

Don't bother reading the factory service manuals, it does not specify whether the groove is to be used.

If you want to make the reassembly bullet proof use the later long shaft water pump grommet. It's wider - so you can't miss on assembly- and it has a deeper recess.

It's OMC part # 0327035 or Sierra 18-2392.

 

[bktheking]

Re: 1976 Johnson 9.9 Upper water tube grommet

Thanks Vic, I appreciate the reply.

If I put the flange in the groove it becomes very bulbous and does not want to seat properly in the exhaust tube or where it mates to the powerhead. I am hesitant to force it too much but thought that if it were to go this way perhaps the part sticking up toward the powerhead would compress around the hole in the powerhead providing a good seal. If this is wrong though I may crack the exhaust housing so want to be sure I am doing the right thing before applying too much force.

Thanks again....

Put some grease around the grommet, trying to slide it in dry into that exhaust tube will split the grommet, don't ask me how I know LOL.

 

[sailfish]

Re: 1976 Johnson 9.9 Upper water tube grommet

Thanks Gentlemen,

I have been diligent about getting all of the old material and corrosion cleaned up and it seems to make great sense to lube the fitting prior to assembly but if the grommet protrudes above the tube I am concerned about it breaking apart and blocking the water flow. I am inclined to install it under the flange and hope the combination of the upward pressure from the grommet combined with the gasket between the exhaust assembly and the block is enough to prevent a leak.

If it does leak at that spot the two concerns are reduced water flow for cooling and where the water goes, which could cause damage. If it were to leak into the exhaust housing I don't think that's a problem, nor should it be a problem if it leaks into the driveshaft area, right? If my thinkng is right, it seems that this is the least risk option...

Thanks again for the replies!

 

[dazk14]

Re: 1976 Johnson 9.9 Upper water tube grommet

I didn't realize you're overseas - Parts may be a challenge.

Put the grommet (alone) into the exhaust tube recess and you'll see how deep it fits. Of coarse, add the flange to the math.

Grease the outside of the grommet as suggested. We use spit, but then again our USA spit is calibrated...

Lubed up, I pull the water tube from the bottom while pushing the grommet from the top side. If you've got enough spit on the outside it will go in deep!

The grommet may stick slightly above the exhaust tube, but don't worry about it - it works!

With a new exhaust tube to block gasket, it will be totally sealed up, regardless of system used.

If you plan on giving this motor to your now - current 6 year old - do the update that I mentioned including the WP grommet - otherwise, put it together and be done with it!

 

[dazk14]

Re: 1976 Johnson 9.9 Upper water tube grommet

If you're really Willy Nilly, I can post a pic for you.

If I do, you'll need to put me on your Christmas card list!

 

[sailfish]

Re: 1976 Johnson 9.9 Upper water tube grommet

Thanks! I got some American spit and lubed the grommet, then put the grommet just under the flange and worked it down into the hole in the top of the exhaust housing. The flange was then just very slightly elevated above the exhaust housing but would compress down when pressed so I put the gasket in place and then bolted her up. All seems sweet at this point though I have not run her yet as found the old fuel line was cracked and thought it best to replace it first so all my work does not go up in flames.

I did replace the water pump and put the longer boot on so that should work fine. It's a holiday here and the shops are closed so will get the fuel line tomorrow and finish it then.

Thanks again for all the help!