YANMAR 110 HP 4JH4-HTE TURBO

[Lobo]

I had an interesting failure on my 110 Yanmar. Boat is 8+ years old, always in salt water, and just under 1,900 hours on the engine.

Oil in my bilge this morning, and only a quarter of an inch on my dipstick. Oil and filter had been changed 6 engine hours before. As there had been a lot of work on the engine the week before (injectors, water cooler, all consumables replaced, etc) I called mechanic.

He found a steel tube (5/8" diameter -- about 16" long) on the port side that allows oil to drain from the top of the engine into the sump. Secured to the rear of the motor with a flange and at the front end with a short hose to an outlet. Hose didn't have clamps as there is no pressure -- it's just a drain. The problem was that about 4 or 5 inches from the hose the tube had rusted through and oil was not returning to the sump, but to the bilge. The cure was simple once found: cut the tube short and replace the original 4" hose with a longer one (about 15") 5/8" (inside diameter) and add a couple of clamps. I have no idea why an oil tube can rust out -- but I've got the scrap metal in a ziplock to add to my collection of unusual boat stuff.

Dave
LOBO



I think I was lucky that I still had oil in the sump and found the problem before I started up the engine.

 

[Metric Rider]

Thanks fo sharing, I have the same engine and will be watching for this issue to arise in the future.

Claire
Lil Toot

 

[doke01]

I am not sure how similar the 125HP is to the 110HP but I believe the 125HP has something similar and there are clamps on my hose. I had rust show up on the pipe that came from a pinhole in the wet exhaust elbow that was shooting a stream of salt water at the pipe when running. Luckily it was discovered in time. Maybe you have something similar going on.

 

[Favunclerich]

Roam is also a 2008 R-25 with the Yanmar 110 HP 4JH4-HTE engine. She has 1830 hours and has been kept in a combination of fresh and salt water. After reading this post, I went down to inspect for corrosion on the turbocharger drain pipe described previously. It's pretty difficult to see when in the boat, but I did feel some corrosion just above where the hose connects to the pipe. My hose had clamps at each end. There was also a light film of oil at both the end where the pipe is bolted to the turbocharger and on the hose itself. My pipe seemed intact, but the hose and the seal at the turbo were probably at their end of life.

In the spirit of preventative maintenance, I decided to order a new pipe, turbo seal (orange o-ring),hose and clamps from marinedieselparts.com for about $225. Ouch, but probably better than taking a chance on dumping my oil into the bilge. The approach that the other owner's mechanic took is probably also acceptable.

I did the replacement in combination with an oil change, as I couldn't tell if the inlet on the side of the oil pan is above or below the oil level. The work was fairly straightforward, but awkward, with 4 attachment bolts and two hose clamps. There is a spacer behind the lower bolt, so I had to be careful not to drop it when the bolt was removed.

Here are links to a couple of pictures of the pipe;

http://odendahls.com/TurboDrainSeal.jpg

http://odendahls.com/TurboDrainPipeCorrosion.jpg

As you can see, the corrosion is not too bad. I was able to sand it off with some emery cloth and paint it with some cold galvanizing spray. I'm not sure why the other boat's pipe was so much worse. The corroded area is just forward of the sea water pump and under the mixing elbow. Perhaps there had been a leak.

I do think that the hose and seal should be replaced every 1000 hours or so as mine had started to weep oil. At that time, the pipe can be removed and inspected.

Thank you for the original post. Sharing this kind of information is one of the prime benefits of Tugnuts!

 

[doke01]

Favunclerich, your old pipe looks like brand new compared to mine but I am in salt water and did have that leak. The pipe does appear to be sound on my boat but I'll be keeping an eye on it. I had a good look at it since I just had the turbo rebuilt, for about $900. The turbo was leaking oil at the seals and a film of oil was visible on the intake prior to the intercooler. Replaced the starter at the end of last season and noticed it. No indicators when the engine was running or otherwise that the seals were failing.