Removal of Yanmar 4jh3e from Hunter 420 Passage
- Thread starter Fgard
- Start date
If the engine is still in your boat, then probably not. 
Have you looked?
Have you looked?
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,252
Engine’s can be removed and replaced. I did it on my Cal 35 Cruiser. I think it migh be easier on your 420 Passage.
Before you start the process, there is a lot to consider. Most importanly what will you put into it’s place and will the new enigne fit the existing construction of the boat and hull. I detailed the experience removal and replacement in my boat here on the SBO Forum. It took me 18 months. It was easier to take the engine out than to install it and then hook up all the “systems” associated with the engine.
In my case I thouhgt I would put in a Beta to replace my 50 year old Perkins. When I looked at the cost of the engineering needed to install the Beta, I dicided that rebuilding my Perkins was significantly more practical both in cost and structurally.
Before you start the process, there is a lot to consider. Most importanly what will you put into it’s place and will the new enigne fit the existing construction of the boat and hull. I detailed the experience removal and replacement in my boat here on the SBO Forum. It took me 18 months. It was easier to take the engine out than to install it and then hook up all the “systems” associated with the engine.
In my case I thouhgt I would put in a Beta to replace my 50 year old Perkins. When I looked at the cost of the engineering needed to install the Beta, I dicided that rebuilding my Perkins was significantly more practical both in cost and structurally.
With a bit of planning, this can be done in about 3 weeks.
Measure, measure, re measure.
If you are going with a Beta, they can custom make drop in mounts for your existing setup.
Will the mounting beds have to be raised or lowered?
Is the angle of the shaft log appropriate for the new engine?
New coupler?
Will the new engine and gearbox require a new prop?
Can the shaft be reused? (Is the length correct for the new gearbox)
Might as well remove and realign the strut at this point....
Might as well put in a new shift seal
Might as well replace the fuel lines, what is the condition of the control cabels?
Where will the new control panel be mounted?
What alternator will you out on the new engine? How does that affect clearances?
Is the exhaust of the new engine on the same side as the old one?
Might as well replace the old Waterloock...
What's the age and condition of the exhaust, water intake hose and thru hull and anti siphon?
Roughly speaking, take the cost of the engine... you'll spend about the same as that on installation, parts, supplies, etc.....
You'll want to do this in a yard, not in the water... as the alignment and measurements can't be done in the water.
How many hours? They are really great engines....what's wrong with it?
Measure, measure, re measure.
If you are going with a Beta, they can custom make drop in mounts for your existing setup.
Will the mounting beds have to be raised or lowered?
Is the angle of the shaft log appropriate for the new engine?
New coupler?
Will the new engine and gearbox require a new prop?
Can the shaft be reused? (Is the length correct for the new gearbox)
Might as well remove and realign the strut at this point....
Might as well put in a new shift seal
Might as well replace the fuel lines, what is the condition of the control cabels?
Where will the new control panel be mounted?
What alternator will you out on the new engine? How does that affect clearances?
Is the exhaust of the new engine on the same side as the old one?
Might as well replace the old Waterloock...
What's the age and condition of the exhaust, water intake hose and thru hull and anti siphon?
Roughly speaking, take the cost of the engine... you'll spend about the same as that on installation, parts, supplies, etc.....
You'll want to do this in a yard, not in the water... as the alignment and measurements can't be done in the water.
How many hours? They are really great engines....what's wrong with it?
