Would you buy a boat with 275 hp Lehmans?

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Sevo

Veteran Member
Joined
Dec 18, 2018
Messages
41
Location
USA
Vessel Name
It’s About Time
Vessel Make
Ocean Alexander 450 Classico
We’ve found a listing on YW for a boat that checks all our boxes and, as best as can be told from the listing, looks to be in good shape. But it has 275 hp Lehmans, which, if I’m not mistaken, are turbo’ed and aftercooled. Also, I’ve read that the aftercoolers for that engine are just no longer available should one go out. If that’s true, I assume that if an aftercooler goes out you’re just SOL. So, is it prudent to buy a boat with that engine, or should I just keep looking? Also, what happens if the aftercooler goes out? Does that kill the engine, or does it continue to run, just at a lower power output?

David
 
It depends on the price.

Before you commit to a purchase price, get a quote for a repower with reman Cummins, if that works in your budget, roll the dice and use the boat as is to get the current life out of the Lehman’s with a scheduled repower on the horizon.
 
We have SP225s Lehmans. They are similar to the 275. I am not exactly sure what the differences are, but yes the aftercoolers are no longer available. If they were to go out according to Brian at American Diesel what I would have to do is just run a hose around the aftercooler and take it out of the loop. My 225 would then become a 180. If you are interested in the boat give Brian a call and confirm that it can be done with the 275s. 804-435-3107
 
I've seen aftercoolers removed from engines and turbo's too.

Different injectors and injection pump recalibration are usually required in addition to a cooler bypass tube when an aftercooler and/or turbo is removed.

Most diesels are available as natural, turbo and turbo + aftercooler so specs for the calibration should be available from the manufacturers.
 
I recently purchased a MT 43 with a set of SP275s. The aftercooler on one blew in a sea trail, while I was doing an engine survey. Pulled both (easily), and the owner had them repaired and tested at local cooling shop.

They can be made. I think Bomac has the caps. American Diesel has the stacks. Call Bowmac for a quote. Should be less than $2k. http://www.bomacmarine.com/ford-lehman-engines.html

From my understanding, the difference between the 225 and 275 is the added after cooler.

I can’t begin to tell you how wonderful and helpful Brian at AD has been. Call them before you buy the boat.

They’re solid motors, updated from the 120s, but they should NOT be redlined.

You can purchase long-blocks and the marineized items, or have them fabricated, cheaper than the $20k per engine (just the engine and installation) for a repower. The Cummins 6bta is a solid choice, but I’d only go that route when all other options are not available. Currently there are at least two in the east, and I think one in the upper northwest.
 
A new aftercooler can be made. Maybe less than factory prices. Any good radiator shop should be able to repair an aftercooler, But in Norfolk you should be able to find someone that specializes in marine exchangers, etc.
An aftercooler works by cooling and condensing the air. Without it, you'll have less power and less economy at higher speeds. If you do a sea trial, see how it performs at full throttle and then at 80% of throttle. The 80% is about where you'd run without the benefit of an aftercooler. You should be running at 80% or below anyway to extend the engine life.

 
I am not sure what the difference between a 225 and a 275 but my 225s have an aftercooler also.
 
Maybe the injectors are different... I don’t know, never asked.
 
Maybe the injectors are different... I don’t know, never asked.

The injectors are changed and injection pump recalibrated for the various ratings.
 
Would I buy a boat with a 275 hp F.L. Probably not. I hate turbos and after coolers, especially obsolete ones.

pete
 
You can bypass the aftercooler and then either under-prop it or keep your power setting down by hand. Turbo can stay, but the last 100hp is a no-go zone.

One risk of running them to failure is they can send sea water into the engine intake, not good. Sometimes they leak externally (messy but not fatal) but if they leak into the air side you have a real problem
 
Bought 2 intercoolers for reasonable dough a while ago. Long Island NY co. as I remember. I think many good marine fabricators are able but you need a decent sketch - not too tough
 
Thanks

Thanks to all for your insights. I tried to call American Diesel today to get Brian’s take on it, but couldn’t get through. I’ll keep trying, but at least it sounds like there are still some repair/replacement options.
David
 
All depends on how fast you want to cruise and how much you are willing to spend on the replacement.
 
Bought 2 intercoolers for reasonable dough a while ago. Long Island NY co. as I remember. I think many good marine fabricators are able but you need a decent sketch - not too tough

Could be Lenco if they are still in business. They used to make an aftermarket inter cooler for Perkins.
 
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