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  Topic Review (Newest First)
02-21-2010 10:23 PM
bwindrope Though I have no interest in joining or fanning some of the arguments here, I would like to add a story about my experiences in a relevant situation:

When I was examining my current boat for purchase I noticed that the Universal 5432 diesel wasn't firing on the #1 cylinder. You could hold the injection line and clearly feel that it wasn't pulsing. The motor looked like it hadn't been cleaned or maintained, and the owner was clearly unaware of a good maintenance schedule. On the test run the boat would not come up to it's rated cruising RPM of 2200 and ran at a very cold 160 degrees for a fresh water cooled diesel. This raises serious concerns about the combustion of the engine and the carbon build up from running so cold.

As it was not my job to diagnose his diesel problems, but to buy the boat, I negotiated the price down a full $10,000 on the belief that I would have to replace the diesel. He had every reason in his mind to believe the diesel was in need of at least a major overhaul, if not replacement.

I suspected otherwise, but it wasn't my job to tell him. After purchasing the boat, I immediately pulled the injectors and took them to a great diesel repair shop where they told me they were in perfect condition mechanically and were simply gummed up with carbon and needed cleaning.

That solved the #1 cylinder problem. When I hauled the boat out, I saw that the prop was a 3 blade 16X12 and research told me that for my boat and that engine a 15X10 would be a better fit. Had the prop re-pitched and she reached hull speed easily in flat water at her rated cruising RPM of 2200.

I then replaced the thermostat with a 190 degree version and she ran at a steady 185 in our cold NW waters.

The outcome of all this? I have a 25 year old diesel in my boat that has 800 total hours and is in superbly good shape, uses .68 gallons an hour average over 100 hours, burns completely clean, uses no oil, and has no leaks. The previous owner thought it was trashed and needed rebuilt or replaced.

The cost of everything I did to put it into excellent shape? Something less than $250, and most of that was for the prop repitch. I've done many other preventative maintenance tasks since then, but nothing near a boat "unit".

If there is a point to this story, it is just that there are a great many variables with engines, and that it is entirely possible to salvage a seemingly dead diesel if the owner becomes aware of basic repair and maintenance.

I wish all of us luck with our motors...
02-19-2010 09:36 PM
chrisj13 I love the diesels, and would vote for rebuild. These things run forever, even under harsh conditions! Unless you are going to be thousands of miles from services, I like to repair things rather than replace. (Like to know the history, vs a brand new unknown item.)
02-19-2010 08:40 PM
Dumah Forgot to mention that the Leahman (108 HP) was originally built in 1964, and is still in service, pushing a 42' square chime trawler style hull @ 8.5 knots and burns .75 GPH. that rebuild cost us under $2000 including 2 power packs, truning the crank, and rebuilding the injector pump and replacing injectors with remans.
02-19-2010 08:04 PM
Dumah I own a 135HP mermaid (Ford) and have found that through American Diesel the parts to rebuild a Leahman cost us approximately $ 2000 plus my labour. As I was the engineer in question that cost was not an issue. I guess my point is that depending on your particular make and application, the age of the carcass does not matter if your block is sound. These particular engines are relatively unchanged over 40 years and internal parts can be obtained from virtually any industrial distributor. My vessel is a converted Cape Island that fished for over 20 years and the the engine I have has less than 300 hours on the first rebuild. The attraction for me for these engines is the interchange with agricultural applications (I had to replace two rods and they came from a 4 cylinder tractor engine) and the marine parts can be mixed from other conversions easily and readily. I will freely admit that this is not a "modern" engine, but have found that they are an excellent value and seems to be no end of parts availability. I realize that you wind sailors don't need a monster like mine but it might be worth thinking domestic when considering a repower. Hope this further muddies the waters, good fortune and pleasant sailing;
02-27-2008 12:39 PM
Valiente I and my bank account and my conscience would love to agree with you, R., really, I would. But the low-hours regimen and the annual winterizations (not a feature of Scotland so much, I think, even if there is frost on the loch occasionally) puts in too many variables for me to be comfortable with.

As I said, I believe that a rebuild in my situation will be primarily diagnostic...I may only require a ring job, new gaskets and rebuilt injectors to get microscopic amounts of crud out. But I've had the valve cover off, and there's the sort of corrosion you get from having a heated boat in cold water: condensation. Not to mention that there's been known backwashes of water into the block.

I could afford a new engine, but I like the simpler (read: heavy) technology of a 1980s diesel. That's why I'm rebuilding rather than replacing.

Thank you for your thoughts, however.
02-26-2008 04:56 PM
Rockter Guys...

All of your counter-arguments are dependent on the new, or re-built motor being reliable. That's quite an assumption. The old one is, so you'll disturb it, it may not come apart easily, and you may well break something when you do.

The old motor IS reliable, and that's the reason why you would wish to leave it alone. If it is NOT reliable, then talk of long distance risks with children, or whatever.

This cheque-book mantra that a 20 year old engine must be suspect will, by definition, add a new motor to your boat cost every 20 years. Yes, $12,000... that's $600 a year to you Sir. Cue $12 a week, to "avoid" trouble.

What works, leave it alone. Give it TLC, and leave it alone. It knows the game by 20 years... your boat, the loads, the prop, the environment, and how much oil it uses. You cast all of that to the four winds when you put a new one in there.... some even choose one with a turbo!!!!.... and you'd better hope it's as well-built as the last one.

02-26-2008 04:42 PM
Valiente I was joking, although I do wear a black fedora sailing at times.
02-26-2008 01:07 AM
sailingdog If you're talking about the steel boat, you'd basically be regretting'd be like a giant solar oven. Especially, once you got down to the caribbean.
Originally Posted by Valiente View Post
I should just paint the entire boat black, to acknowledge the fact...
02-25-2008 08:12 PM
Valiente I should just paint the entire boat black, to acknowledge the fact...
02-25-2008 02:02 PM
sailingdog And these are both good for adding points to your black box account.
Originally Posted by Valiente View Post
...I am a believer in prophylaxis. That's the habit of fixing things, insofar as possible, before they are broken....

And prudence, as part of a general awareness that things go wrong on the ocean, is, to me, the better part of seamanship.
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