water in oil

[rbarthe]

I have a 2006 df175 250 hrs. I had idle problems at 1st. It was idling rough and would kill sometimes when I put it in gear. I changed the plugs and both fuel filters. The next trip it ran great. The 2nd trip it started idling rough again and killing when placed into gear. I researched the problems and cleaned the idle control valve (IAC). While doing this I decided to check the compression. I checked the compression on all 4 cylinders and they were fine. I did not disconnect the fuel lines and when I started the engine it back fired 1 time. I then started it and it idled at 1800 rpms. I replaced the IAC valve . I started it and it went to 2000 rps then idled down to 1500 rps. I tried to adjust the idle air screw but it did not change the rpm. I figured I now have an air leak. I inspected the entire system and cannot find any signs of an air leak. I then check the oil level and and found I now have water in my oil. The motor still starts easy and runs fine except for the high idle. I think the engine back firing caused the air leak. I took it to the dealer and when he saw water in the oil he said I would need a complete engine overhaul and I am looking at 7500.00. He advised it would be better to buy a new engine. I feel I can do the overhaul myself but I am not sure if it is a blown head gasket, some other gasket, or a cracked power head or engine block. With the high idle and water in the oil does anyone have and idea of where I should start looking for the problem

[artdf175]

First thing I might ask I if you have the service manual?
Next, is the engine throwing any alarms?

the IAC valve is one sensor in a series that all have to work correctly to finally get to the IAC valve to control the RPM
also, one of the other important things to remember is the battery voltage
IF the battery is not putting out full voltage a number of systems on these engines apparently do not function correctly

Water in the oil may indicate something as simple (?) as a gasket and then it gets very complicated.

my 2006 df175 had a different problem,, oil consumption
I initially thought, being a reasonable weekend mechanic, that I could take it part, find the problem and put it back together-- bad idea........
My engine had multiple problems. bad valves, #3 & 4 cylinders with bad rings ((a lot of this likely caused by first owner not breaking in the engine correctly... had 25 hours on it when I purchased boat/motor))
took me a while to find a mechanic I could trust to the work.

when I saw this engine fully disassembled on the bench, I realized how much over my head I would have been attempting to do this myself..

I think the $7500 estimate is a bit on the high side. with all the problems I had it ended up being around $5500 the head was rebuilt all new valves cylinders and pistons and rings all worked on and other minor things wile it was fully apart.. ie oil pump new anodes water pump

If you have a full machine shop and lots of engine tear down experience, then go for it.. otherwise find a good mechanic.. and I found the first dealer didn't have any good mechanics .. they were in the business to sell boats and motors and change oil and do minor repairs.

this maybe doesn't fully answer your question, but hope it helps get you started in the right direction
Art

[rbarthe]

Thanks for the reply I do have a service manual for my engine. I rebuilt 2 smaller outboard engines years ago. I am just not sure where water can get into the oil. I checked the plugs and they do not show any sign of water. Do you know how the water would get into the engine other than the head gasket. I would think the oil pressure is much higher than the water pressure. I would think if it were a head gasket i would have oil coming out of the exhaust. I am not sure if the high idle and the water in the oil is caused by the same problem or they are 2 completely different problems

[Ccscorpion200]

I had same problem. I only get water when I run it in the water. Running on the water hose at home was fine. End up replaceing the oil tank gasket and the engine holder gasket. Took it out once so far and no water in the oil. Hope that was all that is bad.

[artdf175]

I was thinking about the oil pan gaskets as well
you have to pull the power head off to get to those parts
IF you do that .. inspect the oil pan completely
there is a little published problem with the oil pans that covers several years including the 2006 engines..
I have a 2006 DF175 as well
after we rebuilt the engine.. first trip out.. the engine overheated at idle
now I was 50 miles out in the ocean when this happened .. which caused a few anxious moments.. at higher rpm the problem went away. at low idle it came back.
the problem, which took a number of hours to diagnose and calls to several mechanics.. involved the oil pan
so after having the engine completely rebuilt.. I ran into the oil pan problems, that then required the powerhead to be pulled off a second time..
IT appears two possible things were/are wrong with the casting.. thin walls and lack of a finish coating inside the oil pan creating a corrosion problem.
the oil pan has a couple passageways running through it.. also it has the plug in the side to hook up a hose to run freshwater to flush out the engine..
the inside passage ways are one for exhaust and 2 for cooling water
IT ended up that there were two corroded out holes dumping the cooling water back through the exhaust. at speed there was enough water pressure to cool the power head.. at idle water simply was dumped into exhaust
in removing the cover plate where the flush port is located .. there was approximately a 3/4 in round hole. and inside between very thinly cast walls another 3/4 by 1/2 inch hole..
you could very well have a problem developing inside the oil pan..
And it was advised to change the piping from the water pump to the bottom of the oil pan.. evidently the crimps that hold the gaskets in place can develop pin holes ...

inspect the oil pan compeltly if/when you pull the power head
Art

[rbarthe]

thanks for both replies I am going to do a leak down test first to try to find out the condition of the rings, valves, head gasket etc then I will pull the head i will let all know what i find

[rbarthe]

i purchased a cylinder leak down tester. I tested each cylinder 3 times . The readings on all are between 5 to 7%.Which according to what i read very good.
I guess this tells me I do not have a leak in any of the cylinders. I changed the oil and ran it for about 15 mins. The idle is still at 1500 rpms and I started to see water in the oil again. I guess I will have to take the power head off and check the oil pan gaskets. Does anyone have any idea of anything else that can cause both the high idle and the water in the oil. Maybe I have 2 different problems. Any thoughts please let me know

[artdf175]

High idle
Did you check all the linkages carefully to be sure they are fully retracting to factory stops?

[rbarthe]

yes from what I understand is if one of the sensors are not operating properly it will idle high. I changed the iac valve but that did not work

[Buddy Roe]

DF 50 over heating

Bought a used DF50 runs well enough but constantly over heats.

-No water at thermostat, none visible at pee tube
-Replace water pump housing and impeller, still no water

Remove hose from thermostat housing and there is exhaust gas pressure where there should be water. While hose is still removed from thermostat housing there is no exhaust gas at gear case (stops bubbling). Also exhaust gas pressure at pee tube (no water at all).

With gear case removed, I put garden hose directly on pick-up tube without the motor running and get plenty of water top side.

All ports and screens on gear case are clear, no blockages.

Does anyone have any idea why there would be exhaust gas pressure in the motor cooling system.

My speculation is bad gasket or hole burnt in water jacket somewhere along the line.

Any advise greatly appreciated.

[Baydog]

Bought a used DF50 runs well enough but constantly over heats.

-No water at thermostat, none visible at pee tube
-Replace water pump housing and impeller, still no water

Remove hose from thermostat housing and there is exhaust gas pressure where there should be water. While hose is still removed from thermostat housing there is no exhaust gas at gear case (stops bubbling). Also exhaust gas pressure at pee tube (no water at all).

With gear case removed, I put garden hose directly on pick-up tube without the motor running and get plenty of water top side.

All ports and screens on gear case are clear, no blockages.

Does anyone have any idea why there would be exhaust gas pressure in the motor cooling system.

My speculation is bad gasket or hole burnt in water jacket somewhere along the line.

Any advise greatly appreciated.

Sounds like a blown head gasket to me. Good luck.

[Buddy Roe]

[QUOTE=Baydog;19348]Sounds like a blown head gasket to me. Good luck.[/QUOTE)

Compression 120 on all three cylinders. Wouldn't it a bit lower on one or two cylinders? Motor runs like a sewing machine smooth as silk.