Repower Options

Robert C Cummins?
Just kidding

Yup .. I can relate. I drove a truck for 10 years. It was old when my employer bought it. Hauled all kinds of mechanical stuff around western Washington and occasionally eastern including a neucular waste compactor .. in three loads. I spent a lot of time w my foot all the way down on that 335 Cummins. Don't remember having any problems. My replacement driver drove it quite a few years more too. Don't remember the year but it was a GMC Astro 95. Experiences like that can bring about great faith.

manyboats said:

Donson,
Is the Perky a 4 or 6?

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It's a 4. I imagine it is the common rail successor to the 4-236. It seems to be out of production so getting parts to it might be problematic and also the reason no one has snapped it up. IMHO, the Cummins is definitely the better choice over the long run.

I picked up the Cummins 6B at the freight yard yesterday and it's in my shop. I gave it a good going over and pulled the rocker covers. It all looks clean and new as advertised. Paint has some nicks and scratches as expected from being kicked around the shop for 28 years. I wasn't expecting any paperwork, but it came with all the original documentation with the exception of the purchase invoice and owners manual. The folded mechanical drawing for installation will come in handy. It also came with a four page invoice/report from the St. Paul Branch of Cummins NPower. The owner took it there is 2003 for service. Evidently the owner forgot to plug the raw water outlet on the heat exchanger and rodent put some acorns in it. NPower changed out several seals, went through the heat exchanger, dyno'd it and ran it at various RPMs, load-no load for an hour and ten minutes. They provided all the bhp, torque, temps and pressures. Looks good.

I plan on changing all hoses, main seals and whatever else makes sense. Will have new shaft seals put in the transmission as well. I will wait for a shop manuals before jumping into it. Looks pretty good so far. I hope to swap the engines out in about three months.

Bob

That is a BW gear isn't it?

That was a good find.

Yes, a 10-18-010, 2.57:1.

It's getting exciting - please post lots of pics as things progress.

Hi all. Thought I'd do an update on this project. After much input from many regarding an good replacement engine for our 40' single Defever, I bought an old/new Cummins normally aspirated 115HP 6B5.9M with BW 72C 2.57:1 gear. It was built in 1987, but never installed.

I replaced all shaft seals on the engine and transmission, and many other gaskets to help ensure no leaks from dried or damaged seals. Rebuilt the injectors, used all silicone hoses, new coolant pump, replaced original 50 amp alternator with a new 150 amp unit and installed a Parker/Racor Closed Crankcase Ventilation system. The engine is ready for installation.

It is quite a time capsule. I am use to seeing grime when opening an engine that is 29 years old, but this one was squeaky clean. When I pulled the front cover, it not only looked new, the drive gears showed they were made in West Germany. The engine was built a couple of years before the Berlin Wall came down.

Anyways, I'm looking forward to pulling the old engine, upgrading the engine room and installing the Cummins. The boat is scheduled to be pulled on April 12th. The boatyard is lifting the old engine out and setting in the new one, but I will be doing all the plumbing, wiring, painting and whatever else is needed. Here's a picture of what engine looked like when I received it from the shipping company and how it looks today. Thanks to all who gave opinions and advise when I started gearing up for this project.

Great job. Should make a nice re-power if you don't mind a set of Commi-pinko drive gears keeping everything going down the pike.

BOOOOOIIIIING!!!! She's beautiful!!!!!

healhustler said:

Great job. Should make a nice re-power if you don't mind a set of Commi-pinko drive gears keeping everything going down the pike.

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OK, I'll bite. You are talking about the West German drive gears? In my mind, German steel and machining in the day was highly revered. The MB's, BMW's, Porsche's and so on came out of there. I don't think they were transported though Check Point Charlie. If there is anything to worry about, it is the original Sherwood raw water pump. I have read about their failures, but I'm not sure this pump is problematic like the ones on later, higher HP models.

remwines said:

I have read about their failures, but I'm not sure this pump is problematic like the ones on later, higher HP models.

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It probably is. I would go ahead and do all the updates on that engine while it is still on a pallet. That pump can be a bitch to get to in certain installations!!!

If you have an M71 Sherwood pump, it will do well for 700 hrs or so before needing seals or a rebuild. Fairly easy with a press. I carry a complete unit aboard to swap if needed.

This pump model is much better than the ones for the higher rated hp 6b models

the drive gears showed they were made in West Germany.

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"West Germany"......the good guys.

healhustler said:

Great job. Should make a nice re-power if you don't mind a set of Commi-pinko drive gears keeping everything going down the pike.

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Um, wasn`t East Germany the "commi/pinko" side, and West Germany( the gears indicated origin) the "democratic and free" side.

Baker said:

It probably is. I would go ahead and do all the updates on that engine while it is still on a pallet. That pump can be a bitch to get to in certain installations!!!

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Thanks Baker. The family and I were just down there in your backyard for Spring Break. Took in the Southwest International Boat Show, Houston Space Center....... Great area!


"bshanafelt If you have an M71 Sherwood pump, it will do well for 700 hrs or so before needing seals or a rebuild. Fairly easy with a press. I carry a complete unit aboard to swap if needed"

bshanafelt; That's what I was thinking. This is a M71 pump. One of the reasons for swapping engines is to get the boat ready for a cruise from SF Bay to Alaska next year. I don't have a spare pump, so I need get one. People on Boat Diesel recommend the Tony Athens/Seaboard Marine replacement. I will be installing a low water flow sensor to make sure I don't cook the engine.

I don't think Seaboard made a replacement for the M71 as it is not the troubled one like I have, the P1700 series. Just rebuild your existing pump and get a new one for a spare.

Get a temp alarm switch on three places: Exh manifold, cyl head, exhaust mixer. That covers you on the cooling system.

Ski in NC said:

I don't think Seaboard made a replacement for the M71 as it is not the troubled one like I have, the P1700 series. Just rebuild your existing pump and get a new one for a spare.

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Hi Ski. I noticed Seaboard is still selling the M71 Sherwood pumps. So you are probably right that Tony didn't design a replacement for that pump. I will just buy another one to keep on board and rebuild them as needed.

healhustler said:

Great job. Should make a nice re-power if you don't mind a set of Commi-pinko drive gears keeping everything going down the pike.

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I think you need to brush up on your Cold War geography.

BruceK said:

Um, wasn`t East Germany the "commi/pinko" side, and West Germany( the gears indicated origin) the "democratic and free" side.

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Of course it is, Bruce. You'd think I wouldn't have made such a mistake, having lived in both places, for God's sake!

Capt.Bill11 said:

I think you need to brush up on your Cold War geography.

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Must be the Dyslexia, Bill. well, maybe a little age.

" M71 Sherwood pump, it will do well for 700 hrs or so before needing seals or a rebuild."


only 700 hrs, then a boat unit to swap in a new pump! Got to be better than that. It was just yesterday that I got my boat, now I have more than 3000 extra hours on it. that means I would have had to replace my pump 4 times and would be watching the newest one carefully. Good thing I have the OEM stuff on my Volvos and not those short life suckers!

I've posted my experience with the M71 pump in other threads, but here it is again:

Just replaced after 3815 hours, new impellers every 750 hours, cam/backing plate at 1500 hours. I did not rebuild this unit as the shaft needed a new seal, and the housing was worn. But it still had some hours left in it.

My first pump went 3250 hours and was rebuilt for a drop-in spare.

bshanafelt said:

If you have an M71 Sherwood pump, it will do well for 700 hrs or so before needing seals or a rebuild. Fairly easy with a press. I carry a complete unit aboard to swap if needed.

This pump model is much better than the ones for the higher rated hp 6b models

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That is a pretty short life. My Jabscos are at 2000 hours with only routine impeller changes.

I'm with Baker, consider an upgrade to SBar Marine.

These pumps, regardless of brand, tend to live long if they are run often. When sitting, seals bind up and other things corrode, that's what shortens their life.

I got about 2500hrs and about 12yrs out of the original Sherwood P1730, but boat ran at least once a week. Tony Athens called me out as BS'ing, but it was true!!!

The ones that sit are the ones that are trouble. Except Jabsco's on Detroits. They knew how to make a pump!!

You want to get on Tony web site. It is loaded with great info. Well worth your time.

Good Goen!!!

Ski in NC said:

I got about 2500hrs and about 12yrs out of the original Sherwood P1730, but boat ran at least once a week. Tony Athens called me out as BS'ing, but it was true

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Yeah, I know what you mean. He does have some good articles for Cummins on the Seaboard Marine website.

Hi,
Donsan, you should have no trouble getting Perkins parts anywhere in the world for any of their engines. try parts4engines.com as they are OE suppliers for Perkins.
Remwines, did you by any chance 'race balance' the Cummins, I've done a couple and it makes a great job in a marine engine.
Well done, the engine looks really sweet.