1991 Johnson 115 VRO Water Leak At Head...Need Help Please

[montanafos]

Just bought a 1991 Lund 1850 Tyee with a Johnson 115 VRO on it. Guy I bought it from just had the head gaskets replaced. Cleaned the boat up tonight and was running the outboard on muffs and noticed a very slow drip of water on the lower left cylider if looking from back of power head...can't recall cylinder #. Upon looking closer I could see some new silicone under the cylinder and as I felt under the cylinder I could feel more silicone spread out thinly. Removed the spark plug and looks fine...no water. At idle there is little or no drip and with throttle increased there is a single drop of water every 20 seconds or so. With my VERY limited knowledge I am guessing water jacket or cooling related, but that's a complete WAG at this point. Any thoughts? Greatly appreciate responses.

 

[emdsapmgr]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Pull the head on that side. Check the lower part of the block, specifically the outer water jacket below the bottom cyl. They can crack if water resides/freezes in there over the winter. If it is cracked, it can be repaired by aluminum welding after the powerhead is removed.

 

[montanafos]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Thank you for the response...glad to hezr that it is repairable. Is this something that will lead to a catastrophic failure if run with the drip for a week or two?

 

[jimdd810]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

You need to pull the head and replace the head gasket. There shouldnt be any silicone at all on that gasket. Sounds as if some one tried to replace it and didnt know there wasnt supposed to be any silicone there or just tried to do a quick fix. Silicone will wick water so there is a chance that the gasket could fail causing more problems. Go ahead and pull the head and replace the gasket making sure you get all of the silicone off. It might not hurt to pull the other head as well to make sure the same repair attempt wasnt performed on the other side as well.

 

[montanafos]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Thanks for the response jimdd810. I just want to make sure I'm understanding correctly. The head gaskets were replaced a couple weeks ago and there is only one area that has the silicone and that is at the bottom of the cylinder, underneath, and it is smeared beyond the head gasket area, almost as though after the head gaskets were replaced the leak was not repaired and the installer tried to use the silicone to stop the leak. I'm not sure obviously. Maybe a warped head? Thanks.

 

[Al-53]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Remove the head....and silicone....clean all mating surfaces..also take the head and lay on a piece of glass. to make sure its flat and not warped....try to rock the head on the glass to see if its flat...

Also you can lap the head on the glass by adding a piece of 320 wet and dry sand paper to get any high spots off the head....do a figures 8 movement...

replace with a new head gasket with no sealer on it..since the gasket has it built in....torgue to specs....run for a bit....3-7 hours and re torgue it....

while the head is off...check block for any cracks....around the water jacket....

Al

 

[montanafos]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Thanks Al...

Here's what I have found after talking with the tech that replaced the head gaskets. It turns out that when he replaced the head gaskets he found two cracks in the water jacket and instead of pulling the power head and repairing them he did a "cold patch" of some sort and put it back together. Apparently they found a small leak once back together and then the layer of silicone was applied. So, I've just dropped the boat off at a local marina I trust and they are doing the repair with MarineTex as they felt that trying to weld the block would warp it. We've been unable to physically see the cracks as they are underneath and there is no room for inspection. It sounds like this type of crack is fairly common as the guy that owns the marina mentioned that they do these types of repairs frequently and that the Marine Tex has proven to be a long term fix for them. This all sounds right to me but if anyone is reading this and feeling this is not a recommended repair I'd love to hear from you. If I had time this week I'd maybe dive in to this personally but am traveling and when I return want to hit the lake with the kids. Thanks again for input...

 

[emdsapmgr]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Considering the volume of water that goes through that powerhead, a few drips of water are insignificant. Marine Tex is a strong/good, appropriate temporary fix product. Keep your eye on it through the end of the season to be sure it does not develop into a stream. Plan to dismantle it over the winter.

 

[montanafos]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Thanks for the reply. They are removing the power head to do the Marine Tex fix and are going to look at the cylinders while doing the fix. As for dismantling this winter, are you recommending a rebuild or repower? The marina is suggesting the Marine Tex as a long term fix since the concern is there of warping if they tried a weld fix.

 

[emdsapmgr]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

If you are removing the powerhead for the Marine Tex application, why not have it aluminum welded instead? Having someone aluminum weld that small crack in the outer part of the powerhead should not cause/create any problems. I'd put it right back on the midsection and run it.

 

[montanafos]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

If you are removing the powerhead for the Marine Tex application, why not have it aluminum welded instead? Having someone aluminum weld that small crack in the outer part of the powerhead should not cause/create any problems. I'd put it right back on the midsection and run it.

I was hoping they would do that, but the guy that owns the marina felt that he'd end up with a warped block from the heat. He said "once I put a torch to it we'll not be able to use it".

 

[emdsapmgr]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

I'd get a second opinion from a shop that specializes in alum welding.

 

[petryshyn]

Re: 1991 Johnson 115 VRO Water Leak At Head...Need Help Please

Welding that water jacket crack will not cause warpage if done right. I've had it done several times and will attempt the next one myself. The crack underneath the port side is common in this neck of the woods.