2017 DF200 - Oil Cooler blocked?

[syspig]

Can y'all handle another "won't pee" post? I think I've done my homework here, but am out of ideas. I'm wondering if I have a blocked oil cooler.

This is a new to me boat, owned by a good friend who was pretty fanatical about maintenance. I'm dealing with a 2017 DF200. Upon firing it up today, I encountered no telltale stream - and started in with the basics. Ran a wire up the pee hole, a piece of weedeater line and 110PSI of compressed air. Engine is in a large trash can, water level is well above the plate above the intake screens. None of this got the pee stream going.

Upon taking off the lower cowl, I started tracing water lines. If I understand things correctly, it looks like things start on the port side, exiting the nipple in the pic below - labeled A. With the water line removed, engine running, this flows strong - so I'm assuming impeller is doing its job.


port-markup.jpg

A water line runs from A above to the starboard side, where two nipples - B and C in the photo below - reside below the oil filter. The water line connects from A to C, then another line runs from B to the pee tube.

starboard-markup.jpg

Based on posts here and elsewhere, I believe B and C are the out/in of an engine oil cooler? If so, shouldn't there be unobstructed flow between them? There is not - it's blocked solid, and no amount of compressed air/wire poking lets water or air pass through. If things should be flowing freely through these two nipples, this appears to be where the blockage is.

I'd sure appreciate any insight. Thanks!

[Solarman]

Could try 5-7 gals of vinegar (or other solution) to flush in the same tub, letting motor idle continuously until water gets too warm, then shut off. Let water/motor cool down, then repeat the process over and over (adding make-up warer & flush solution as needed) until it has run about 2-3 full hours total. Can also record temps around the motor with a temp gun to see if corrosion is causing problems (where it is hottest), and if it's clearing up? As corrosion clears temps and pee-stream should get better.

Good luck, post back on what you find out.

[Moonlighter]

Is it actually throwing any temp alarms? An engine that isnt getting enough water flow will throw a temp alarm (usually Temp gradient) within a few minutes.

Some engines need to have the leg fairly deeply submerged in the water to pump strongly, it sounds like you have it deep enough, but try it again with water at least 4-6” above the AV plate. AV plate = the large one above the prop.

Doesn't it seem unlikely that a fastidiously maintained 2017 year engine would have such a bad internal blockage that water doesn’t circulate through it at all?

[syspig]

Ran the motor for 30+ minutes w/vinegar solution, no change. Tried poking in both nipples with a stainless wire and the air gun again afterwards, still 100% blocked.

In a minor fit of frustration, I jammed a pick in the intake nipple - C in the image. Previously when I put anything in the nipple, it would go in about 1.5" and stop solid. I assumed the water jacket took a 90 degree turn, and I was hitting engine block internally. However, with a little more force and the very sharp pick it felt like it stuck a little - so I gently tapped it a bit more with a rubber mallet. I could feel the pick penetrating, and after a few more taps water started coming out. A decent pee stream remained for about 30 minutes more of idling.

I have some high concentrate vinegar (40%) on the way, I'll give things a prolonged flush when it arrives - but it looks like I'm out of the woods.

[Moonlighter]

Have you popped the sacrificial anodes out so you can get a look inside at the water passages? Thats going to tell you a fair bit about the extent of internal mineral buildup.

[syspig]

Have you popped the sacrificial anodes out so you can get a look inside at the water passages? Thats going to tell you a fair bit about the extent of internal mineral buildup.

Yes. I was told they likely needed replacing as it had been about a year.

With the exception of the bottom one, which appears to take the brunt of the corrosion - they all had more than 50% intact. There was the expected crusty remnants right inside the opening behind them, easily brushed out - but the passages behind them looked clean.

I have a service kit on the way, all will be replaced. I'm also planning on putting together an electric water pump/recirculation setup to flush through the fill port and will run that for several hours.

[artdf175]

just a follow up question- how much is the water pressure?
can you stop it with pinching it off?
how old is the water pump?
The reason I bring this up is if the water pump has not had an impeller kit installed in the last couple of years you may still have water flowing just not enough to keep all passages blown out and free of debris ...
Art

[syspig]

just a follow up question- how much is the water pressure?
can you stop it with pinching it off?
how old is the water pump?
The reason I bring this up is if the water pump has not had an impeller kit installed in the last couple of years you may still have water flowing just not enough to keep all passages blown out and free of debris ...
Art

Not sure on pinching it off, but the stream looked pretty healthy. Still, it's been almost two years since the impeller was replaced. I have a maintenance kit on the way.