GPH ford lehman 225

[Gordon B]

Hi to all,
I've watched this forum for along time but this is my first post.
I'm sorry if this has been addressed elsewhere.
My wife and I are in the "looking" process for a liveaboard trawler to cruise the Florida coast (within a year). We are curious about GPH for twin ford lehman 60 elpt 4s 225 on a 37-38 foot trawler from the 1980's era. We would really like to go with a lot smaller engines but for some reason many of the smaller trawlers that we like have high horsepower engines.
So, I guess the question is if you go slow (7 or 8 knots) what can the expected GPH be.
We don't want to go fast, but can going slow damage the engines?

Thanks for all the help.
Gordon

 

[BobH]

We own a 38' Taiwan Tub with twin 225s. Haven't used it as much as we would like, it's currently for sale, but we have made several trips of about 30 nm. We have Floscan instruments and I did a spread sheet of mileage, speed and nmpg. We have done as good as 2.88 nmpg at 7 knots to as low as 1.45 nmpg at 7.3 knots. Big difference being wind and current. Last time out we did 1.57 nmpg at 8.4 knots going and 1.79 nmpg at 8 knots coming back. This is generally running at 1320 RPM. There is one trip at 3.49 nmpg at 5.6 knots. We had a boat following us in a dense fog and kept having to slow down to wait for them. The speeds are the average based on total time and distance.


Hope this helps,


Bob


(buy the boat and I'll throw in the spreadsheet)

 

[Nomad Willy]

Gordon,
Keep looking. Looking is fun. Enjoy it. There are some boats out there with small engines. And they work better than anything at their speed range. Full displacement boats are not very numerous but good for you in that they aren't more expensive. This despite the fact that many here complain about their fuel consumption. Just keep looking and don't depend on Yacht World boats. Others selling independently will usually have lower prices.

Be honest about your needs for power and low fuel consumption. For most people it's less (frequently far less) than they think or anticipate.

Good hunting and have a good time looking.

 

[Gordon B]

Thanks for the info. I see that higher horsepower doesn't necessarily mean high GPM if you take it easy.
This will help in the "boats that qualify" search.

Gordo

 

[bayview]

speed is the greatest factor in fuel use. Engine size is almost irrelevant. Keep the bow down flat and the wake at minimum for best economy and fastest economic speed. Slow down to 4-5 knots and fuel use will go down significantly.


Cruising FL fuel will be one of your lower expenses. Go buy a boat and don't obsess over fuel use that in boats is absurd anyway.

 

[Brier_John]

I know this is an old thread. But, when I search the inter webs for “Lehman sp225 gph” this is the page I get. So...

1987 President 37 aft cabin with a SINGLE SP 225, webasto hydronic heat and a 7.5kw generator.

Previous owner ran 8kts at 1800 to 2000. - 4gph
I run 7.5kts at 1500 to 1800 - 3.4gph.

These are based one 200+ hours cruising over 3 years in PNW waters from Olympia to Nanaimo. It includes generator run time and heat.

 

[OldDan1943]

Things that can effect GPH

Fixed items:
Hull design
Propeller design
HP of engine(s)

Variables at the time of the voyage:
Boat weight
Fuel and water loading
Wind and current
Speed
Generator (running or not)

I think that covers them all. Feel free to add to the list.

 

[Flyguy1967]

Those engines are not the same as the FL 120's. Take the advice from someone who just repowered from SP225s to Cummins because rebuilding the 225's would not make sense, and keep looking.

 

[Kayenne]

We just did an 8 hour trip in the Sacramento Delta (ie: tidal rivers).

With flat water and little wind we were averaging a tad over 3gph on each engine.

Ford Lehman 225 turbo's running at 2,000 rpm. We averaged over 9 knots of boat speed in our 29,000lb Ponderosa 47.

For what its worth.

Newb Out.

 

[socalrider]

We just did an 8 hour trip in the Sacramento Delta (ie: tidal rivers).

With flat water and little wind we were averaging a tad over 3gph on each engine.

Ford Lehman 225 turbo's running at 2,000 rpm. We averaged over 9 knots of boat speed in our 29,000lb Ponderosa 47.

For what its worth.

Newb Out.

Thanks for the data point! I suspect if you brought your speed down 11% to 8kts you'd probably be at 2gph/engine (33% less burn) fwiw. Don't know your waterline length, but 9kts is probably a bit faster than optimal - for fuel efficiency, of course. Time efficiency is another matter entirely

 

[PM]

Man, this is an old post, how did it get restarted?

No matter, but I have a question for the moderators. The OP said he has been watching the site for a long time but this was his first post, yet his avatar shows 97 posts. I have seen similar things in the past, just curious.

pete

 

[rslifkin]

Man, this is an old post, how did it get restarted?

No matter, but I have a question for the moderators. The OP said he has been watching the site for a long time but this was his first post, yet his avatar shows 97 posts. I have seen similar things in the past, just curious.

pete

The post count shows as of today when you're viewing the thread. So this may have been his first post and the other 96 came after.

 

[Brier_John]

Glad to see activity on the SP225, will run ours up the Inside passage in Spring 23

We are prepping for a round trip Everett to Glacier Bay in the Spring. Single engine SP225, 1987 President 37 double cabin. We are overpropped so will be working on that this winter. Installing a Floscan too. Logs now still show a burn rate of about 3.5GPH at 1700 and 7.75kts. I hope that taking an inch or more of pitch off the prop will put us at around 1900 - 2000 at that speed. Trying to figure out the best rpm and hull speed is for max economy without coking up is the goal. Plus, WOT max RPM today is 2350 which is too low.

 

[Gypsy Island]

Those engines are not the same as the FL 120's. Take the advice from someone who just repowered from SP225s to Cummins because rebuilding the 225's would not make sense, and keep looking.

I'm curious why it should not make sense to rebuild the SP225. I own two of them and was very happy to see there are cylinder liners available. That gives the oportunity to overhaul the engines without taking them out.

 

[Brier_John]

Not sure where to put this since I seem to be talking to myself here. But, here goes:

Lehman SP225 single in a 1987 President 37 Sundeck WLL about 34’

Prop is 25x17 (reduced 1” prior to trip) 4 blade

Inside passage from Everett to Glacier Bay and back (almost as we are still on our way home)

1,500 rpm average
6.8 to 7 knots
2.4gph (includes generator run time of about 1 hour per day average for water maker/charging on the hook)

 

[Cargile]

John (OP), I believe this post is 8 years old.

 

[Brier_John]

Yes. The convo was continuing through November of 22.

And, this thread is how I found Trawler Forum in Google, so I am updating with what I have.

I am underway right now heading South in the Strait of Georgia.

 

[Ubertech]

Relevancy of an eight year old original post.

I’m very thankful and happy to have found this thread as I am in the process of closing the purchase of a 1986 performance trawler with twin SP225s. The part that makes me happy is that the admin of this site allows these threads to continue because as stated above the information is just as relevant today as it was with the original post. My new boat will be based in San Francisco Bay. I plan to do quite a bit of testing, and when they release the new twin diesel version of flow scan, I will be installing them. Having spent most of my time on performance, sailboats and racing on San Francisco Bay, I think one of the big consumption factors is understanding tides and currents and trying to plan your trips accordingly. I don’t think a lot of folks follow their speed through the water as opposed to their speed over ground When calculating the miles per gallon factor.
Cheers~

 

[Comodave]

Welcome aboard. We had SP225s in our last boat a President 41. We cruised at about 9 knots and burned about 6 to 8 gph. They are great engines. The one issue is that the aftercoolers are no longer available. But if they go bad they can be bypassed easily and then you have a 180hp engine. Brian at American Diesel is the guru on these and has the parts you will need.