jdm2000usa
Recruit
- Joined
- May 12, 2015
- Messages
- 1
First time on this site; thanks in advance for any help. I'll try to be thorough.
Background: I have two 2005 Yamaha F115TXRD motors with 500 hours and have had them for 1.5 yrs and 460 hrs. Prior to me, they sat for 6 years almost unused at 40 hours of use. I did a minimal amount of work (plugs, injectors, fuel system) to get them going and they have always run ran very well.
The boat is severely over-propped. WOT is 4300 rpm and always has been. The boat currently has 13.25 19" SS props and I have a couple of 15" aluminum on-order.
On changing the oil a while back, I noticed a milky color in one engine's oil and drained out about a cup of mayonnaise-looking goo with the oil. From what I have researched, this is emulsified water in the oil. I changed the oil and ran it in the water again and it was milky again after four hours of running but not noticeable after only an hour or so. The engine runs great but had a few instances of low oil pressure alarm when first starting up. That stopped after a couple of oil changes. The engine is not "making oil" with fuel; the oil level doesn't seem to change very much or at all and there is no fuel smell to the oil.
I live in a very remote tropical location with no shops, mechanics, etc. I'm basically on my own other than a couple of experienced boaters who have experience with similar engines. I can order parts and it takes 2-3 weeks. I'm looking for any non-invasive ways I might be able to narrow down the problem. It will be risky to open things up at my experience level, but I may not have much choice.
Here's what I have done so far:
- I hooked up the YDS and everything looked fine. Water temp was pegged at 50C on both engines while running in the water so I assume the thermostat is ok.
- I visually inspected for oil leaks, cracks, etc and can see nothing so far but I haven't opened the lower cowling. There may be a small oil leak at the top of one of the cam gears but if there is, it is very small and only noticeable after a long period of running.
- I did a compression test and it read 160, 160, 157, 165. I haven't done leakage since I don't have the equipment.
- I tipped the engine up and haven't noticed any obvious oil leaks but I didn't leave it this way very long.
From what I have read about others with similar issues, it could be the oil pan gasket, oil pump seals, a head gasket issue, rusted oil pan, etc.
Any advice on what to try next? I plan to run with the new props when they come in and see if that makes a difference but I doubt it. Otherwise, I was planning to remove the power head and start looking at gaskets, seals, oil pump, and oil pan below. I already have the parts to change most of that out and I'd plan to do that regardless of what I see.
Looking for any advice!
Background: I have two 2005 Yamaha F115TXRD motors with 500 hours and have had them for 1.5 yrs and 460 hrs. Prior to me, they sat for 6 years almost unused at 40 hours of use. I did a minimal amount of work (plugs, injectors, fuel system) to get them going and they have always run ran very well.
The boat is severely over-propped. WOT is 4300 rpm and always has been. The boat currently has 13.25 19" SS props and I have a couple of 15" aluminum on-order.
On changing the oil a while back, I noticed a milky color in one engine's oil and drained out about a cup of mayonnaise-looking goo with the oil. From what I have researched, this is emulsified water in the oil. I changed the oil and ran it in the water again and it was milky again after four hours of running but not noticeable after only an hour or so. The engine runs great but had a few instances of low oil pressure alarm when first starting up. That stopped after a couple of oil changes. The engine is not "making oil" with fuel; the oil level doesn't seem to change very much or at all and there is no fuel smell to the oil.
I live in a very remote tropical location with no shops, mechanics, etc. I'm basically on my own other than a couple of experienced boaters who have experience with similar engines. I can order parts and it takes 2-3 weeks. I'm looking for any non-invasive ways I might be able to narrow down the problem. It will be risky to open things up at my experience level, but I may not have much choice.
Here's what I have done so far:
- I hooked up the YDS and everything looked fine. Water temp was pegged at 50C on both engines while running in the water so I assume the thermostat is ok.
- I visually inspected for oil leaks, cracks, etc and can see nothing so far but I haven't opened the lower cowling. There may be a small oil leak at the top of one of the cam gears but if there is, it is very small and only noticeable after a long period of running.
- I did a compression test and it read 160, 160, 157, 165. I haven't done leakage since I don't have the equipment.
- I tipped the engine up and haven't noticed any obvious oil leaks but I didn't leave it this way very long.
From what I have read about others with similar issues, it could be the oil pan gasket, oil pump seals, a head gasket issue, rusted oil pan, etc.
Any advice on what to try next? I plan to run with the new props when they come in and see if that makes a difference but I doubt it. Otherwise, I was planning to remove the power head and start looking at gaskets, seals, oil pump, and oil pan below. I already have the parts to change most of that out and I'd plan to do that regardless of what I see.
Looking for any advice!