Saturday, June 10, 2017

No Smoking

No Smoking - that's the goal

The latest saga in the maintenance of Eximius is to Stop the Engine Smoking - Kinda.

When we were over in Bimini, some sailing buddies noticed that we belched a lot of black goop out of our exhaust when we made a rapid change/ increase in engine RPM during the botched maneuver of getting the boat alongside the dock at Bimini Big Game Marina.

After speaking with several people that I have a lot of respect about their diesel engine knowledge and reading for hours on the C34 forum, I came to the conclusion that it was most likely the Injectors that needed servicing. So, plan was to remove - inspect - service/replace and install the Injectors.

Fortunately, there is a Kubota dealer just 10 minutes away from our house, I have had reason to go there in the past (there's a link to their website in my Links Page) and they are really helpful folks with half a century of expertise in the Kubota engines between just 3 of their employees.

A quick trip to the dealer and I had the new Injectors @ $67 each which was great as I had found them on the internet at $150 each. While there, I asked if they could give me a tutorial on changing out the injectors. Just so that you know what I'm talking about, here's a pic 
#3, & #2 Fuel Injectors (#1 is off the screen)

The engine is a Universal M25-XP 3 pot diesel, probably the original from 1987 and I'm guessing so are the Injectors.

The tutorial gave really clear instructions on how to do the change out and what to move as well as what to not move.
The 'Do not move' things are known as Delivery Valve Holders that are on top of the Injector Pump assembly. The fuel delivery tubes (you can see 3 in the pic) are connected to those Delivery Valve Holders (DVH) and to the top of the Injectors.

Armed with the new Injectors we went down to the boat to take care of business. Easy Peezy - really - just a couple of 'gotchas'




The instructions from the dealership was to disconnect the fuel delivery tubes from the Injectors and the DVH's without moving (rotating) the DVH's. Not so easy! The fuel deliver tubes have been in place for 30 years and have siezed to their securing nuts, so turning the nuts to release them also rotated the DVH's every so slightly, that shouldn't matter much! Oh Oh! 

Old Fuel Delivery Tubes with New Injectors
Worried that the tubes would fail if I tried to re-tighten them, it was back to the dealership and purchase 3 new tubes. Each are different. They are labeled for Cylinder #1, #2 & #3. #1 is the forward (nearest the bottom of the pic) tube.

Despite wedging the DVH's they turned. It didn't matter that some of the knowledgeable folks on the C34 forum pointed out that I should have just bent the tube rather than try to disconnect them from the DVH's - another Oh Oh!

Anyway, I tightened down on the DVH's and had no problems attaching the new Fuel Delivery Tubes to the DVH's and the new Injectors. Ten minutes and all of the fuel return tubes were back in place, the fuel stop valve opened and the Air filter all put back together. Time to start the engine. 
That didn't go well - the engine would not start, not even a hint of trying. It was rotating when the starter button was depressed, but despite turning over, it would not fire up. Time to re-inspect everything.


Found a leak. When the fuel pump was running, a visible leak appeared at the #3 DVH where it screwed into the Injector Pump housing. That's not good, that DVH is the thing the dealer said should not be moved. Too Late!

Checking the manual and talking (again) with the dealership, the problem is that movement in the DVH.s - Injection pump timing is almost certainly out of sync - and this is not something that Jon Doe can fix, requires special equipment. Options are to replace the Injector pump - $580 or get the old one rebuilt and re-timed $350ish. And, as one of the C34 forum guys pointed out, we know that the old unit fits, and a new unit may not fit - things have changed in the 30 years since the engine was first made. So we're going for the rebuild.

Back to reading the forum and the detailed tech notes from the past 30 years of C34 users that have this type of engine. At this point I'm pretty confident that I'll be able to remove the Fuel Injection Pump for service. There's a qualified service company just 20 minutes away from where we keep the boat and it's a name that I'm familiar with. To back up using them, I spoke with a Marine engine guy that has dealt with many of these types of diesel engines and confirms that they do a great job and are recommended by the Kubota dealership. That's good enough for me.

Plan is to take the Injection Pump out on Monday, photograph everything in the area near the pump (apparently there is a block number that has data about the injection timing for that particular engine) and will visit the Service company Monday before noon.

Stay tuned. 

See you on the water (once we get the engine running again)

Paul