yamaha 90 block repair

[fluke]

I have a 1988 yamaha 90 2-cycle exhaust errosion problem on the channel walls allowing water into the cylinders. Are the aluminum walls fillable with the motor mounted on the boat? J-B Weld, Steel Putty or HST-2000 an option? Thanks Mark

[boats.net]

Never tried it not sure if would be able to get it to stick on stay in place.

[fluke]

Well figure I haven't anything to loose, so I'll try the JB Weld first as a glue and a filler and go from there, thanks Mark

[Aleutianwest]

90 2 stroke

is the block all empty now i have a block 100 bucks

[fluke]

Thanks no it is still intact. Today I used steel putty to fill the holes and cracks, then coated with J-B Weld, will recoat tomorrow. Will put her back together Sunday and see what happens!
Mark

[Reel Insane]

I am a Diesel Tech for a local dealer in North Carolina. I don’t recommend using J.B. Weld to repair a damaged block. There I got what I am supposed to say out.

Now, for the good stuff. I had a block that was pitted where the lower part of the liner meets the block. I used the famous J.B. Weld to repair the pits. I layered the product in with thin layers. I took roughly 3 layers of product. I then sanded the affected area until it was smooth and you could see the dark spots where the product was installed. I waited 24 hours before sanding. I had the pleasure of rebuilding the same engine after 250,000 miles after the repair was made. I was astonished to see that the repair held up after so many miles. I have since made similar repairs to different engines when the owners did not want to replace the block.

As long as the cracks are not very wide or very long I think that your repair will have the same success.

Good Luck!!!

[fluke]

Thanks that is great info. Did you sand between coats?
Mark

[Reel Insane]

I sanded just enough to rough up the layer that I was about to put more product on. I sanded until it was smooth and I was satisfied with the final layer.

[fluke]

Well put her back together and started right up and idled fine. Took her out for a ocean test ran great, will try again for a much longer run this weekend but so far very incouraging.
Mark

[fluke]

Well I got 10 months from my repair, she was sounding a little off so I removed the exhaust cover to find the epoxy started to de laminate. I repreated the same procedure and hope to get 6 to 8 months more out of it.

[robert graham]

It still sounds better than a new powerhead or motor! Maybe when you re-do the JB Weld this time it sticks better. Good Luck!