My little fire damage 3870 project has turned into a W06Ti conversion

[Torski]

Some of you remember my posts from the fall 2019 when I bought a 1989 3870 with fire damage from poor maintenance and the stbd turbo caught on fire causing extensive damage. I restored the floor and rebuilt both turbo kits, then enjoyed it for a year before the stbd engine completely failed in Sept 2020.

I knew this would happen, especially to the STBD engine. That engine had mainly lumpy tar in the sump when I did the first oil change, and the centrifugal was filled with carbon sediment. I got an oil pressure warning after a long ride one time, so I knew I was on borrowed time. My company specializes in engine conversions, in Land Cruisers, so in my mind I kind of just kept her limping along knowing I wanted more power.

I hired Earl, the local Hino guru to help with the engine portion, who almost talked me in to just rebuilding that engine. I kept pushing something with more power and finally he agreed with me. We searched for engines over a few months and finally a set of W06Ti mains came up in California.

I tore up the floor, he tore down the engine. I pumped the bilge, and he turned the wrenches ;-)

I'll update the build as we progress, currently the stbd engine is ready to be pulled, and the port one will be torn down and prepped before we remove both mains in the coming month. My boat is at Dagmars, so if you see me working down there, feel free to come cheer me on ;-) But if you see Earl, leave him alone to work - he's expensive LOL

Cheers!

[Torski]

Here are some photos of where we began

[Pcpete]

I wondered why the boat was getting “lonesome”. I’ll be over with a case of root beer to tempt Earl and get in his way. 😏

[Torski]

The STBD engine is all torn down and ready to come out, tomorrow the port engine will be torn apart and ready to pull out. I'm hoping we can get the forks in there to pull both out of the main door

[Pcpete]

That’s a show I want to watch! Ever seen them unload a boat out of a container? The boat is in there on a 45 degree angle and they roll the container onto its side to slip the boat out. Quite a show.

[RDOIII]

As a thought in case you get stuck, saw a fellow that removed the engines from 38. He removed the ladder and cut the section of cabin from the area of the door to the engine room door. Made large area to reach in and pull the engines out. Once done placed the cut out back and used teak to trim the cut lines. I am not sure if he did any fiberglass from the inside or came up with some other reinforcement fix. But sure seemed like a real time and effort saver. Have fun and best of luck.

[randygh]

To me engine removal and new install seems like a big time job. I've never been in a 3870, but I assume the engines are amidship and the blocks will need to be lifted, suspended and removed through the cabin door. How will this be done? Thanks for sharing. Very interesting.

[Torski]

Well they're out! What a mess 32 years of poor maintenance can create! Both engines came out of the hatch cover in the salon and then out the main door. The skilled forklift drivers at Dagmars made light work of it and loaded them int the truck. The new engines are being gone through and will be ready to install in a few weeks.

In the meantime there's a crap ton of soot and smoke damage from the original fire to clean up. Then bilge paint after it's all sanitary down there. I'm excited to see what 310hp will do vs the old engines. They came out of a 4788 that was repowered in favor of the Cummins 8.2 liter.

[NorwegianDave]

Dagmars is the best. I used to keep my boat there on row W!

[randygh]

Holy Smokes, what a big job. Thanks for posting. Keep us informed, it's very interesting.

[smitty477]

Well they're out! What a mess 32 years of poor maintenance can create! Both engines came out of the hatch cover in the salon and then out the main door. The skilled forklift drivers at Dagmars made light work of it and loaded them int the truck. The new engines are being gone through and will be ready to install in a few weeks.

In the meantime there's a crap ton of soot and smoke damage from the original fire to clean up. Then bilge paint after it's all sanitary down there. I'm excited to see what 310hp will do vs the old engines. They came out of a 4788 that was repowered in favor of the Cummins 8.2 liter.

"They came out of a 4788 that was repowered in favor of the Cummins 8.2 liter."
Please tell more about how someone got these to fit in a 4788 and what trans and shafts did they fit out.

[MacPhid]

I'm curious if you are doing any drivetrain modifications. Will you need to increase the shaft size to accommodate the added horsepower? With the props in tunnels you are limited to the 20" diameter, what pitch will you try to run, or are you changing transmission ratios?
It's interesting that Earl pulls both engines from the starboard side. I know the floor is designed with the supports to be removed, did the bar and floor aft of the engine hatch come up?

James

[Pcpete]

James, the removable deck in the salon goes all the way to the bulkhead, so yes, the bar has to come out. It’s reasonably straightforward except for the 4 screws behind the “mirror” in the wine rack.

[Woodsea]

Torski
A lot of work but what a great opportunity to really spif up the engine space. It should help with future maintenance at least by making it more pleasant to work in but I also think a clean orderly mechanical space encourages inspections and maintenance. Please post pics.

[Torski]

"They came out of a 4788 that was repowered in favor of the Cummins 8.2 liter."
Please tell more about how someone got these to fit in a 4788 and what trans and shafts did they fit out.

I believe they ran into floor clearance issues. Fortunately I have their old engines so no going back now!

[Torski]

I'm curious if you are doing any drivetrain modifications. Will you need to increase the shaft size to accommodate the added horsepower? With the props in tunnels you are limited to the 20" diameter, what pitch will you try to run, or are you changing transmission ratios?
It's interesting that Earl pulls both engines from the starboard side. I know the floor is designed with the supports to be removed, did the bar and floor aft of the engine hatch come up?

James

I had a good friend do the calculations for me, and my hurth gearboxes are up to the task, and the prop shaft with those gearboxes and 310 horsepower needs to be 1.48" diameter. I'm right at the mechanical limit of both, so I'll leave them in for now.

I will leave the props as are for now and then figure out the best option after I get everything dialed in. The gear boxes are at Harbor Marine currently to be gone through, hopefully just seals and gaskets and no rebuild is required.

[MacPhid]

Torski,

It will be interesting to see what performance difference you see. I would think dramatically better acceleration, but with original gearing and props wouldn't your top speed at WOT be the same? (Assuming the 310 HP WOT is 3000) Your original engines had aftermarket turbo's though did they not? Were the props repitched for the added power then? Our WOT with the 175HP engines, 2.0:1 gearboxes and 20x21" props was 16.5 knots.
Looking forward to your first results!

James