Adding Turbo to Yanmar 4JH4AE

[amiklic1]

Hello,

I have Yanmar 4JH4AE engine, and I'm thinking of equiping it with turbo charger. As there is an original version turbocharged 875 HP Yanmar 4JH4 engine), I want to know is it worth, or is it impossible due to many complicated changes to be made when doing that.

or it's just add a turbo and give it a go ?

[sestina]

FFS why???

[Tellie]

A 875hp 4JH4? That's one heck of a turbo.

[fishwife]

You might investigate a trade in, especially if your engine has low hours and a full service history in your log. I assume the 875 was meant to be 87.5. If your engine is in a displacement boat, I can't see any advantage and lots of downside to increasing the hp available to you. It's not going to make the boat go (much) faster, that's for sure. To use any additional power, you'd probably need to re-size your propeller, possibly the shaft and you may not have sufficient clearance to spin a larger prop anyway. Fuel use would go up for little increase in speed, although you may be able to tow something more efficiently.

P.

[GordMay]

Yanmar JH4 Turbo Series Marine Diesel Engines
4JH4-TE (turbo) 75mhp @ 3200rpm
4JH4-HTE (intercooler-turbo) 110mhp @ 3200rpm
4JH3-DTE (hi-power intercooler turbo) 125mhp @ 3800rpm

[amiklic1]

In fact I meant 75 HP ( "(" is just above nr. 8 on my keyboard, so I haven't push "shift" before :-) )...

In fact the boat is not full-displacement but a mix which can use different engines.

I know that with 100 HP it goes 15 kt. at maximum and 12 of cruising speed.
I also know that with 150 HP (Steyer) it goes 21 kt. at max and 16 of cruising speed.

Also, when I was building a boat (I bought a kit version, only plastic, many pictures on: Photo Sharing by MyPhotoAlbum :: brodglampo's MyPhotoAlbum Gallery :: Glampo ).

Now I have 10,5 kts at max and 8 of crusing speed (that's with 100 liter of weater, 200 liter of diesel and full equipment plus almost 300kg of persons aboard).

Other problem is that my engine is rated 3000 rpm max, and TE version (75HP) is rated at 3200. What does it mean? Are that the same basic motors with some add-ons, or completely different cams, pistons etc.?

[Chief Engineer]

There are a lot of changes that need to be done for a turbo....the benfit isn't much....except to the fuel docks?

[never monday]

Originally Posted by amiklic1

Also, when I was building a boat (I bought a kit version, only plastic, many pictures on: Photo Sharing by MyPhotoAlbum :: brodglampo's MyPhotoAlbum Gallery :: Glampo ).

you could benefit from a larger engine.
Adding a turbo to your current 4JH isn't recommended. Too many things would have to be changed including the injection pump.
I'd have powered that boat with close to 200hp. Then I could comfortably cruise at a good speed (20kts) with less fuel burn. The JH, even turbo will require you to run high in the rev range, burning more fuel.