repowering gas to deisel

[spool's out]

My partner and I have a 95 28CC with inboard mercs. We have been toying with the idea of a deisel repower. Has anyone ever done one like this if so I would appreciate some feedback. Thanks, Chuck

[backman]

diesel to diesel yes

I have done the diesel to diesel repower by Laytons Custom Boatworks who are next door to CC and effectively subcontract out Mac's work.

I love my new improved boat as a result of both the repower and complete new running gear along the way.

The price was fair; the workmanship excellent and 242 hours later I'm pleased with punch with the engine selection (thanks Mac), the new running gear design (thanks Mac and Keith) and the superb workmanship (thanks Carleton and Doug).

You should start the process by calling Mac and understanding the scope of the change and go from there.

[Capt B]

I'm in the final stages of repowering from a Volvo Diesel to a pair of Cummins 4 BTA's - did everything myself - so I would be happy to answer any questions you might have. I also repowered a 26' Shamrock from Gas to Diesel a few years ago. Some of the items you are going to have to consider:

You need a return line to the bottom of your fuel tanks

Check your shaft size - I'm not sure if Mac puts 1.5" in on the gas engines

Depending on how much of your shaft is exposed - you may need to lengthen or shorten your shaft lengths - Mac could give you the spec on that.

Then it is simply pulling the gas engines and installing the diesels - allignment is the same process and wiring is actually easier.

[spool's out]

Thanks

Thanks for the input guys.. backman do you have any performance stats with the new engines, cruise, top end, fuel burn, etc.

Capt B, the gas also have 1.5 shafts as a matter of fact several folks have commented on the shaft thickness. The shafts on the 28 are thicker than many of the 30+ ft boats around us in the yard. Mac doesn't mess around with the quality...

[Capt B]

Another item to consider is the raw water intakes. On the Vovlo 41's - they had 1.25" intakes - the Cummins requires 1.5" - so new intakes, strainers, etc.

[backman]

D4-260 data

full fuel, 3 guys, full fishing gear; 200# ice,tower and canvas. Air ~80+, water 70+

I'm getting 3540-3580 WOT weith 18 X 26 props in these conditions.

3050 RPM - 25-26 knots, 20 GPH
3150 RPM - 27-28 knots, 22 GPH

WOT - 3500+ - 33+ knots

I also saw ~ 30 knots at 3250-3300 RPM but I don't run offshore trips that high.

5 canyon runs so far this year.

# 1 - ~95 miles out and back @25-27 knots/3080 RPM, 7.5 hr's run, 5 hrs troll - 155 gallons

# 2 canyon overnight - 100 miles out, 80 back, 14 hr's trolling - 193 gallons

# 3 - forget

# 4 - ~90 miles out and back, 7.25 hr's run at 3150 27-28 knots, 8 hr's troll - 175 gallons

#5 - 95 miles out, 85 back - 6.5 hr's run @ 3150/27-28 knots, 8.5 hours troll - 165 gallons.

[spool's out]

Thanks for the input guys.. Alot to consider but those performance numbers are really appealing..