Brown Trout
Recruit
- Joined
- Jun 30, 2013
- Messages
- 2
Hi
I have been lurking around this forum for a while and decided to register now, hoping for some advice on my new found problem.
I have a '92 Honda BF8A which has been running fine up until a few months ago. After a oil level check I discovered the crank case oil has been contaminated, resembling a Caff? latte more than motor oil. I suspected salt water had contaminated the oil and decided to overhaul the engine and change the gaskets.
Disassembling was a charm (except from a stuck vertical shaft, needing some muscle to loosen). Most of the gaskets looked fine so I can't pinpoint where the leak where, but the thermostat where stuck open and a lot of salt deposit where found in the cylinder cooling channels. I heard some things about thermostats stuck open causing condensation, so that might be the source of my problem. Anyhow, since I have disassembled the complete motor I may as well change all the gaskets and o-rings (or does anyone disagree?).
But to the more serious problem. Having cleaned the upper unit/oil case i discovered a small hole in the case. The location is between the oil sump and the exhaust pipe. Picking on it made the hole larger and it looks like a large piece of the cast has been removed, due to corrosion maybe? I will try to get a photo of the damage later this day.
So the question is how do i repair this? Scraping or buying a new oil case seem to be a expensive choice at this moment, and I would rather try to fix it first. Not very familiar with outboard engine repair, but i guess the material of the oil case is cast aluminum alloy. Searching a bit on the internet revealed its a difficult material to weld and TIG welding is the preferred choice. Not having the equipment or knowledge, another solution presented are brazing using "Durafix" or similar. I have a Oxy-fuel torch and propane torch and from the manufacturer reviews and videos it looks like a "relative simple" fix.
Have anyone tried this before? I believe this is not a structural loaded part, and only vibrations from the engine cause stress on the weld. Another concern is the exhaust pipe which is only a inch away from the hole. Would the heat cause the brazed joint to deteriorate?
I found a picture on the internet displaying the oil case. The hole in in the lower right corner of the oil sump.
Source
Looking forward for some advice. And thanks in advance.
Regards
Thomas
I have been lurking around this forum for a while and decided to register now, hoping for some advice on my new found problem.
I have a '92 Honda BF8A which has been running fine up until a few months ago. After a oil level check I discovered the crank case oil has been contaminated, resembling a Caff? latte more than motor oil. I suspected salt water had contaminated the oil and decided to overhaul the engine and change the gaskets.
Disassembling was a charm (except from a stuck vertical shaft, needing some muscle to loosen). Most of the gaskets looked fine so I can't pinpoint where the leak where, but the thermostat where stuck open and a lot of salt deposit where found in the cylinder cooling channels. I heard some things about thermostats stuck open causing condensation, so that might be the source of my problem. Anyhow, since I have disassembled the complete motor I may as well change all the gaskets and o-rings (or does anyone disagree?).
But to the more serious problem. Having cleaned the upper unit/oil case i discovered a small hole in the case. The location is between the oil sump and the exhaust pipe. Picking on it made the hole larger and it looks like a large piece of the cast has been removed, due to corrosion maybe? I will try to get a photo of the damage later this day.
So the question is how do i repair this? Scraping or buying a new oil case seem to be a expensive choice at this moment, and I would rather try to fix it first. Not very familiar with outboard engine repair, but i guess the material of the oil case is cast aluminum alloy. Searching a bit on the internet revealed its a difficult material to weld and TIG welding is the preferred choice. Not having the equipment or knowledge, another solution presented are brazing using "Durafix" or similar. I have a Oxy-fuel torch and propane torch and from the manufacturer reviews and videos it looks like a "relative simple" fix.
Have anyone tried this before? I believe this is not a structural loaded part, and only vibrations from the engine cause stress on the weld. Another concern is the exhaust pipe which is only a inch away from the hole. Would the heat cause the brazed joint to deteriorate?
I found a picture on the internet displaying the oil case. The hole in in the lower right corner of the oil sump.
Source
Looking forward for some advice. And thanks in advance.
Regards
Thomas
