2006 df50....multiple "minor" issues

[beater whaler]

I have a 2006 df 50 on a whaler Montauk, admittedly it's modest power for a waterlogged '83 model hull, and I suppose I should mention its under wheeled as I can spool it up to wot and hit the rev limiter but the economy and general tractability is outstanding. I routinely make a round trip of 65 NM using on the order of 5-6 gallons in good weather. over the eight years that I have owned and maintained this motor the only issue I have had outside of routine maintenance was a neutral safety switch failure. although I seldom wait for the 100 hour oil change, and only use non-ethanol fuel with stabil and I change my fuel water separator/pre filter twice a year. recently I discovered that it appeared that the motor was "making"oil . of course I noticed it smelled of fuel and immediately changed the oil and filter, leaving the level two "x" marks shy of full by the stick with hopes of monitoring the rate at which I made oil over my longish commute. I was shocked to find that upon making one leg of my 65 mile trip to find that the stick showed full. my gut feeling was to check the low pressure diaphragm pump by pulling the two 10mm bolts holding it in place while leaving it connected to the fuel lines and pressurizing the system with a few vigorous squeezes of the primer bulb, thinking that it'll drip if the diaphragm is perforated and it didn't drip. I smell checked the actuator end of the pump also but the faint smell of fuel was already in the crank oil and as such it smelled faintly of fuel, but no drips under pressure. I then checked the thermostat after talking to my local guru and sure enough it was stuck, I changed it. my guru recommended that I shock treat the motor with Yamaha ring free and change the oil immediately following said treatment. using my two "x's" shy of topped method to somewhat quantify any fuel/crankoil turn over I have changed the oil and I am certainly eager to run the boat and see if the problem is rectified. any thoughts on the matter would certainly be appreciated. issue no. 2..... I have changed the water pump impeller a number of times over the years but recently ( while bringing it up to temp on the muffs to clear the remainder of my shock treatment from the pumps)I noticed that water is not only egressing the two sall holes at the top of the lower unit frond side, but also out of the port through which the shift rod passes. is this normal? issue no.3 occasionally after prolonged periods of running at 5200-5800 rpms(my typical cruise) when I drop back to idle it idles at 2000 rpms. this "fast"idle after running is intermittent and seldom but shifting back into gear can't be good on the gearcase dogs. anyone have thoughts on this?
thanks for any input.

[Moonlighter]

On the fuel in oil issue, is your motor efi?

If so, the most common cause seems to be the float level in the VST being incorrect, or the VST is contaminated and needle valve clogged. There is a hose running from the VST that for emissions reasons vents vapor into the crankcase, if the Float level is wrong or VST clogged up, raw fuel will then run into the crankcase. Solution is to clean out VST reset float level and needle valve. Easy to check if this is the problem - pull the vent tube out of the crankcase, run the engine and closely watch the vent tube for fuel dripping out. Obviously, be very careful doing this so fuel doesnt drip anywhere dangerous.

issue 2 - dont know.

issue 3 on efi models the idle speed is controlled by IAC valve, these can stick or eventually fail. You can remove then clean them, or replace. The part is made for Suzuki by Mitsubishi so google the part number, can get the Mitsubishi OeM part much cheaper than the Suzuki branded one. Try cleaning it first,

Your Suzuki mechanic should know the above possible causes for both your questions 1 and 2.

[beater whaler]

many thanks to you moonlighter. I cleaned the IAC valve out and haven't run the motor to check the VST float and needle valve status as yet, I will be doing that momentarily. before I uncover what is likely the root of the issue I will freely admit that after viewing the VST diagram I am a little concerned that I may run into trouble if I intuitively just begin disassemble and reassemble after cleaning. it looks like it'd be easier to get to with the intake manifold removed....and then there's the re-gasket issue.... I hate to be needy but a brief procedural or a likely parts list would be extremely helpful. my situation is this, my local mechanic (the only one I trust) is backed up for two months and my income depends on making a 30 plus mile run with the boat three times a week. I'm in a bit of a bind. If you could possibly give me a brief procedural I would feel better about cracking into the VST. my thoughts on the matter initially were if it weren't the obvious low pressure diaphragm failure it must be something in that hard to get to little silver box. also resetting the float level, how might I do this. thanks again

[beater whaler]

on closer inspection I couldn't find any lines exiting the VST that entered the crankcase at any location. the closest thing that I found to that was a small hose that ran from a "T" connector. off of the "T" ran a hose to the silencer box and the "in-line portion of the line ran through what I presume to be a valve of sorts under the engine to the front side and overboard. adjacent this tube was a second tube that functions as drain for the VST.....
I think I'm going to run it this week as I only have to make two trips, mindful of the oil level and hope my aggressive shock treatment and thermostat replacement may have done the trick.....
anyone that has taken the lid off the VST of a df50 with any suggestions would sure be of help....

[tommybe1]

haven't done it myself but manual says you need to remove the intake. gl

[beater whaler]

After the shock with ringfreeriand thermostat replacement and oil and filter change the oil making feature has been deleted. My ring free shock recipe was 6 ounces to 5 gallons of fresh fuel on a dry tank and a fresh water fuel separator. Ran the motor for about two hours lite it sit for an hour. And ran the tank nearly dry....in greater than 1000 hours of run time I haven't run any cleaner through the fuel system. The oil might have had ten hours on it prior to the shock treatment....it came out looking dirtier than the 100 plus hour oil. Twenty hours on fresh fuel and I can't begin to tell you how much better it rums.... I'd forgotten all about smooth idle......