Oil analysis

O

Old Fisher

Active Member
can anyone recommend a place to have engine oil analyzed?

My Yamaha outboard is "making oil" and I want to have it analyzed to see if, as I suspect, there is fuel in the crankcase. I live on the Island but I don't know of any local company that analyzes engine oil.

Thanks for any help.

Old Fisher.
 
There is no sign of water in the oil. I suspect that fuel is getting into the crankcase and adding to the oil volume. I want to find a place that can analyze the oil to determine if there is fuel mixed in the oil and if there is any sign of metals (engine wear or damage) in the oil.

The engine has been running perfectly and at normal temperature.
 
You can get an oil sample kit from any John Deere, Finning CAT or western Cummings dealer. You can usually get results in a few days. Usually around $30-40 included shipping and results. I've used the Kit from John Deere and it uses a lab called Oilscan. I can get the part number for the kit JD uses tomorrow at work. Is there a Brandt tractor or prairie coast dealer around you?
 
I've used Finning in the past, they are quick and detailed,
I agree with Craven, t-stat can cause this problem if stuck open or weak and engine is continuously running cold
 
There must be a dozen or more previous threads on this problem some of them lengthy, especially with Yami kickers. Personally I spent a great deal of time, research, money and effort trying to get an older. yami kicker to stop making oil. Besides our own efforts we also had a Yammi dealership work on the problem as well as an outside Yami specialist shop with a great reputation. We got it to make less oil and once stopped it making oil but after about 2 years of messing around with it and throwing money at at it we gave up. The motor appeared to be in generally good condition, the dealer leak down compression test was excellent for example. What kept the problem at bay the longest was swapping out the carb. That was after replacing the t-stat, rebuilding the fuel pump and eventually replacing the fuel pump with the newer water cooled type. Eventually we got rid of that problem motor and got a new Yammi which has been trouble free.

Usually the making oil problem is not that hard to fix and our experience is apparently not common. In the vast majority of cases it is solved by replacing the t-stat and if that does not work by removing the fuel pump, taking it apart and looking for a pin hole leak in the diaphragm and replacing it with a fuel pump rebuild kit. Gas slowly gets through that pin hole leak and right into the motor oil. If you have an older motor replacing the early generation fuel pumps with the newer water cooled type can also decrease the chances of damaging fuel pump diaphragms over time and keep it more reliable.
 
Rockfish said:
There must be a dozen or more previous threads on this problem some of them lengthy, especially with Yami kickers. What kept the problem at bay the longest was swapping out the carb. That was after replacing the t-stat, rebuilding the fuel pump and eventually replacing the fuel pump with the newer water cooled type

Usually the making oil problem is not that hard to fix and our experience is apparently not common. In the vast majority of cases it is solved by replacing the t-stat and if that does not work by removing the fuel pump, taking it apart and looking for a pin hole leak in the diaphragm and replacing it with a fuel pump rebuild kit. Gas slowly gets through that pin hole leak and right into the motor oil. If you have an older motor replacing the early generation fuel pumps with the newer water cooled type can also decrease the chances of damaging fuel pump diaphragms over time and keep it more reliable.
Click to expand...

Thanks for your comments Rockfish.
My engine is a one year old F300 (fuel injected). I think the thermostats are ok because the digital gauge shows operating temperature to be in the middle "normal" range.
You are correct that there are numerous posts on various forums about Yamis making oil and the ones that concern me are about poor ring seating. I broke the engine in as per Yamaha recommendations, always warm it before cruising, and generally treat it with care so I would be very disappointed if I find that the rings never properly seated.
Anyone else having this problem?
 
NDT. Thank you for that information. I will check into it.

Hookin Up, Thanks, I think I will check with Finning.

Today I inspected and tested the thermostats and they seem perfect. Spark plugs are clean, uniform, and show good color. No obvious problems anywhere but the motor is definitely making oil. I changed the oil today too.
 
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Old Fisher said:
I would be very disappointed if I find that the rings never properly seated.
Anyone else having this problem?
Click to expand...

Perhaps this is a silly question and I am out of my depth, but if rings were not seating, could gas be getting pushed past the rings, say on the compression stroke into the motor oil. If there is a seating problem would it reduce compression a little on the effected cylinders and show up in a leak down test?
 
Rockfish, you are right. Ring leakage can show up on a leak down test if the leakage is sufficient and I may have to do that.
 
Are you using marked fuel?

My 4.2L F250 (basically the same engine as yours) makes oil from the red dye in marked fuel if not run hard once in a while. Even though my boat is more effecient at 3500rpm, it makes less oil if I cruise at 4000 and run at higher rpms for a few minutes each time out.

Use to be a real problem but much better since modifying how I use the boat.
 
Yes I do use marked fuel and its interesting that you mentioned this. Just yesterday I had a dealer tell me that the use of marked fuel causes unburned fuel to squeeze past the rings into the crankcase. He said the dye in the fuel can't burn so it leaks across. I'm going to avoid marked fuel for awhile to see if it makes any difference (he "guarantees" it) but I admit I'm very skeptical. The amount of dye in marked fuel is tiny and this theory makes no sense to me. And thousands of boaters use marked fuel without problems. But I,ll try it.

I think the problem really stems from the fact that 4 stroke outboards run quite cold compared to most engines due to cold water cooling systems (not closed cooling) and low temp thermostats resulting in less expansion of piston rings to give good sealing. My research over the past few days shows that it's a very common problem among all brands of 4 stroke outboards and the manufacturers quietly just say to "live with it". The idea of living with fuel diluting the lubricating oil makes me uncomfortable.

Your suggestion of running the engine harder is probably the best solution. Making the engine work harder will aid in sealing the rings and minimize the fuel dilution. But, like you, I don't really like the idea of running harder and burning more fuel when my boat performs great and gets good mileage at 34-3500. I'm going to start running harder though and go to WOT now and then to try to improve ring seal.
 
My marina has a fuel dock that only has mid-grade marked marine gas and does not permit you to bring down you own gas if you are in one of their slips. I also am somewhat skeptical of the marked gas causes it theory. My new kicker uses marked gas with no problem, the same gas the old kicker used that made oil. That said it is unfortunate that government still mandates that gas for marine and farm use etc. be marked. It made sense when marked gas was way cheaper and some would want to buy it to avoid road tax etc. Now however, it seems that it is the same price or more than unmarked gas so I don't see the reason for marking it unless I am missing something.

Outboards spend a lot of time at max acceleration and high rpm compared to your average car motor as they don't have a geared transmission to reduce high rpm at speed, although you can chose the prop. I would think extremely good lubrication is critical to the longevity of very expensive large 4 stroke outboards and having their protection thinned out with gas is indeed concerning even if it is controllable by running them hard.
I knew making oil was a problem sometimes with some small 4 stroke kickers, but after reading yours and ryanb's experience with new big 4 stroke motors, I have a new found appreciation for my 6 cylinder, direct fuel injected two stroke.
 
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My kicker runs off the same tank as the main. The kicker oil obviously picks up the dye too as it turns red but I haven't noticed significant oil quantity gain in the kicker. Again I've tested this theory by not using marked for a while and indeed it is the marked fuel that exasperates this problem. Another reason for me is that my boat is relatively overpowered at 4400lbs with the F250 so it doesn't have to work very hard.
 
That is interesting. I have never paid much attention to the color of my kicker oil other than I know it is darker than when we put it in, but will look for a color change to red next time we change it out.
 
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