Hello everyone,
I have a m25xp and it started to leak from a few place during my last vacation.
oil sensor unit, now the engine plug between starter and alternator and i think from the starter (probably rear seal)
i did two thing wrong in the start of the season. First wrong oil grade (10w40) and oil ovefilled (probably 3/16 inch above full on dipstick)
i did change the grade to 10w30 and lowered the oil little bit underneath the full line.
i do have less leak bit still seapage a bit.
do you think this would resolve by itself or i probably will have some big work to do this.
here is the picture of the engine plug...
Not loosing a lot of oil. A few drop in the bridge after a few hours
many thanks for your help
Joce
10W30 is what I use in the car... seems thin for a diesel. I use 15w40 fpr my U35, which is designated as for diesels. What does everyone else use?
Chuck Parker
HelenRita 2072 Mk II
2002 Tall Rig - Winged Keel
Atlantic Highlands, NJ
Hey Jocelyn, please consider adding a signature line and something about your boat (year, rig, engine) and your sailing area.
30W, 10W-30, 15W-40 are all specified in the owners manual. I would not suspect that using any approved viscosity would result in more or less seepage. Overfilling by 3/16" is normally not a big deal with the usual result foaming caused by the connecting rods contacting the oil pool. Oil leaking around the pressure sender could be simply an indication of age. Oil leaking out the front or rear seals could also be an indication of age. Lastly, your picture seems to show a freeze plug and this would be unusual to have oil here since these are really part of the cooling circuit.
All this may point to something to check: make sure water is not getting into your oil. An increase in oil level, oil coming out where water should only be, unusual seepage happening are all possible indications of this.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Thanks for your comments and I,ll do add my signature tonight.
I'm from Quebec, Canada. So season is ending in a few weeks!
I do check the oil level before each run and it doesn't go over the Full line. But I'll double check. Oil would probably more brown and creamy if this would happen? right now it's light black.
It could be age sign because I've purchase the boat last summer and it had 500 hours on the engine. It's a 1989. In the past season, I've added around 200 hours so seal could but gone just by sitting that long without running that much.
Here a drawing of the plug location. Is this a freeze plug? See red arrow!
The more I think about it the more I will narrowed my research near the alternator bracket...... could be a small crack causing the oil running along back near the oil sensor unit and dropping down that plug....
Little drive to the dock tonight I guess!
Yes, generally for a diesel engine water in the oil will make the oil look brown when the oil is hot. Given that your oil quantity is not increasing and you feel that overfilling is the cause for higher-than-normal level, then it's beginning to rule out the water-in-oil theory. Since you see oil on both the pressure switch and a nearby plug suggests a common source, with the one being higher leading you to the source.
Usually those small threaded plugs are just plugging passages that have been drilled in the casting during the manufacturing process. They are pipe-threads, so if the source of the leak is one of those plugs, tightening a bit may get it to seal.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Ok not coming from the alternator bracket.
The freeze plug is in fact un rubber plug..... So Íll chck with kubota tomorow if they keep that part. Probably rubber is harder than it was.
ill change the plug and the sensor this weekend and start from there.
Most freeze plugs are about 1" diameter and either just pressed in or have a nut that you tighten and this expands a rubber bung. Again, oil coming out of a freeze plug would not be a good thing as it's a water seal. If you remove a true freeze plug, be aware that you will loose all of your coolant.
I think just change the oil pressure switch and see how this goes first. Aside from seals, the only other likely source of oil would be one of the plugs that is used to seal up the oil galleries after manufacturing. These are all-metal and just thread into the block. Any leaking might be able to be stopped by a slight tightening.
Nick Caballero
Retired C36/375IA Mk II Technical Editor