Are Gardner Diesel Engines really that good?

[T210DRVR]

Gardner Diesel engines have an almost cult like following suggesting they may be the best marine diesel engine ever produced. Is the engine really that great or is it simply the greatest engine of it’s era?

I’m looking at a modern trawler with an 8LXB engine.

 

[MurrayM]

Can't answer your question, but have to say they look to be designed by a sculptor at heart

 

[tiltrider1]

Different engines are designed to accomplish different things. The Gardner Diesel is great at longevity. Perfect for crossing oceans at slow speeds. Not what you want in a planning hull.

 

[Ken E.]

Gardner diesels certainly do have a cult-like reputation as a slow turning, low horsepower engine that has a very long service life. Comparing the reality of the engine to its folklore would be interesting....as in hearing comments from owners using them. Maybe some will chime in. I'd also like to hear more about Gardners, including parts availability.

 

[DavidM]

The Gardner engines were designed for longevity and low fuel consumption. They have lots of piston and bearing surface area for their horsepower and the block is heavy with strong head bolts, etc. Lubrication is good and cooling is more than adequate for the heat produced. All of this beef results in minimal wear and if maintained and operated right will last just about forever.

Modern, turbo charged, high output engines push all of these parameters so they don't last as long, but last long enough in recreational use.

David

 

[Art]

Gardner design sounds fool proof... great mass, good oiling/lubrication, good cooling, slow turning, not too much HP [but still good torque], much bearing and piston fully lubed surface area interface, good product materials. IMO, can't beat that combo.

In regard to gasoline engines for any vehicle... and, pretty much the same holds true for diesels... the less bulk weight, faster rpm, higher temps, less well lubed surface interface areas in attempt to turn out high HP spells sooner rather than later engine failure.

Rule of thumb for engines that may last well [if cared for and used wisely]: Top end HP number should not exceed 75% of cubic inch number. More lesser %age = More better... for probable engine durability!

 

[psneeld]

The marine engineers I know say "good".... but not deserving of the raving reviews the "dock talkers" give them.

 

[DavidM]

Rule of thumb for engines that may last well [if cared for and used wisely]: Top end HP number should not exceed 75% of cubic inch number. More lesser %age = More better... for probable engine durability!

Your rule of thumb really only holds true for engines that are run at that value. I recall many years ago Tony Athens installed a 5.3 liter (about 320 CI) Yanmar 370 in his brother's squid boat. The wot spec for that engine would be more than 1.0 * its CIs. That engine was used at 2,400 rpm mostly which is about 150 hp or about .5 * the CIs. He repowered it again (forget with what) at 13,000 hours and it was still going strong when it was pulled.

A Tony Athens rule of thumb is that you can generally run an engine at 30 hp per liter continuously for lots of hours, which is about what his brother did.

The point is a high output turbocharged engine might be rated for lots of hp per CI or per liter, but you don't have to run them that way. If you run them lighter they can last much longer.

David

 

[Simi 60]

They are an outstanding engine but easy parts availability and finding someone who actually knows them when required would be my concern especially in remote regions.

When our vessel was repowered a Gardner was looked into or at least compared but an 855 Cummins was chosen and for that I am glad
Parts for that are, in comparison, easy and cheap.

Saying that, if our vessel was Gardner powered I don't think I would be unhappy.

 

[Art]

Your rule of thumb really only holds true for engines that are run at that value. I recall many years ago Tony Athens installed a 5.3 liter (about 320 CI) Yanmar 370 in his brother's squid boat. The wot spec for that engine would be more than 1.0 * its CIs. That engine was used at 2,400 rpm mostly which is about 150 hp or about .5 * the CIs. He repowered it again (forget with what) at 13,000 hours and it was still going strong when it was pulled.

A Tony Athens rule of thumb is that you can generally run an engine at 30 hp per liter continuously for lots of hours, which is about what his brother did.

The point is a high output turbocharged engine might be rated for lots of hp per CI or per liter, but you don't have to run them that way. If you run them lighter they can last much longer.

David

True. Pretty much comes down to how kind one is to the engine being used. Any engine run too hard continuously fails quicker than if run at correct lower output.

 

[syjos]

The Ford Lehman 120 is 380 cu in or 6.2 liter.

Cruising hp is around 50 to 70.

30 hp/liter per Tony Athens is 180 hp!

Who's Tony Athens? I hear his name thrown about here on TF.

I trust advice from Steve D'Antonio or Nigel Caulder.

 

[T210DRVR]

They are an outstanding engine but easy parts availability and finding someone who actually knows them when required would be my concern especially in remote regions.

When our vessel was repowered a Gardner was looked into or at least compared but an 855 Cummins was chosen and for that I am glad
Parts for that are, in comparison, easy and cheap.

Saying that, if our vessel was Gardner powered I don't think I would be unhappy.

Thanks! I have a great deal of experience with Cummins 855’s in OTR trucking. I would happily have one of them. My first truck was a 290 HP 855 and it ran forever. The 400 HP variant was also a solid engine but you had to be a bit careful with them. We expected 25,000 to 30,000 hrs (measured in miles) between in frame overhaul.

 

[DavidM]

While I trust Steve D'Antonio for boat structural, general mechanical and electrical systems, I really trust Tony Athens for all things related to marine diesel engines, particularly 4-11 liter recreational and commercially used engines.

Tony owns Seaboard Marine a Cummins repower dealer in Oxnard, Ca; was the prime contributor to boatdiesel for many years and now has his own forum for marine diesels at sbmar.com. He really, really knows Cummins engines and his shop probably does more Cummins repowers than any other, but is no slouch at Yanmar, Cats and others.

90% of what I know about marine diesels came from reading Tony's writings. He is a rather unique guy- a hands on marine diesel mechanic with decades of practical experience, but also understands the theoretical side of marine diesels.

David

 

[Insequent]

Gardners have excellent BSFC, leading to their reputation for low fuel consumption. I think this is the key factor in their appeal. In modern engines, MAN gets about the same BSFC.

But other brands, eg for the Caterpillars that I recall seeing data for, the BSFC is 10-15% higher. I have no idea why - does the additional energy just get dissipated as heat?

 

[menzies]

How do they compare to John Deeres?

 

[Lou_tribal]

Does design come in play? I never saw any engine better looking than a Gardner.

L

 

[RT Firefly]

Greetings,
Mr. L_t. I think Mr. MM is correct. They were designed by an artist. No prettier engine that I've seen.

 

[Mischief Managed]

Gardners have excellent BSFC, leading to their reputation for low fuel consumption. I think this is the key factor in their appeal. In modern engines, MAN gets about the same BSFC.

But other brands, eg for the Caterpillars that I recall seeing data for, the BSFC is 10-15% higher. I have no idea why - does the additional energy just get dissipated as heat?

Probably a function of bore to stroke ratio. Gardner engines typically have a very long stroke which makes sense if big HP is not the goal on any of the versions of a particular engine family. CAT typically makes several versions of the same engine family from low HP to high HP so the bore to stroke ratio is a compromise to allow a spread of different HP options.

 

[Art]

Greetings,
Mr. L_t. I think Mr. MM is correct. They were designed by an artist. No prettier engine that I've seen.

Agreed!

 

[Art]

Does design come in play? I never saw any engine better looking than a Gardner.

L

Ditto

 

[Insequent]

How do they compare to John Deeres?

Well, I've done a bit of digging and the difference is less than I indicated above. A Gardner 8LXB uses about 200 - 205 g/kW/hr, essentially flat line across its rpm range. Some Gardner data is down at 190, as is some MAN data. The Cat example attached (pdf) ranges from 214 to 226. The JD data I found is similar to Cat.

A couple of things to note though: BSFC is determined at 100% load, not a condition where we operate our engines. For some engines it varies a lot with rpm. At other loads the fuel map varies a lot as well. Cummins no longer quotes figures in part because of these factors. People were trying to calculate fuel consumption for normal boat use and getting results that had no practical relevance.

Tony Athens article gives a nice overview:
https://www.sbmar.com/articles/fuel-and-horsepower/

My earlier comment was somewhat academic: how did Gardner do it for a mechanical engine? Why don't modern engines get those kinds of figures?

 

[Art]

Well, I've done a bit of digging and the difference is less than I indicated above. A Gardner 8LXB uses about 200 - 205 g/kW/hr, essentially flat line across its rpm range. Some Gardner data is down at 190, as is some MAN data. The Cat example attached (pdf) ranges from 214 to 226. The JD data I found is similar to Cat.

A couple of things to note though: BSFC is determined at 100% load, not a condition where we operate our engines. For some engines it varies a lot with rpm. At other loads the fuel map varies a lot as well. Cummins no longer quotes figures in part because of these factors. People were trying to calculate fuel consumption for normal boat use and getting results that had no practical relevance.

Tony Athens article gives a nice overview:
https://www.sbmar.com/articles/fuel-and-horsepower/

My earlier comment was somewhat academic: how did Gardner do it for a mechanical engine? Why don't modern engines get those kinds of figures?

I read the whole comment/article. Agree with it too. One item I was surprises at was hp gained per gal diesel fuel burned... 20 hp/gal/hr is quite a bit higher than calcs I've seen before. Your thoughts?? Thanks, Art

 

[Insequent]

I read the whole comment/article. Agree with it too. One item I was surprises at was hp gained per gal diesel fuel burned... 20 hp/gal/hr is quite a bit higher than calcs I've seen before. Your thoughts?? Thanks, Art

The 20 could be when an engine is running at optimum efficiency of rpm and load. In real life scenarios it probably comes back toward 18. eg modest load factors along a prop curve. Or even lower for slobbering mechanical engines which might best be left nameless at this point!

 

[menzies]

This thread reminded me of a question I asked last year and where I learned a lot (and forgot most of it until I just re-read it now).

http://www.trawlerforum.com/forums/s3/fuel-usage-curves-42857.html

 

[Lou_tribal]

How do they compare to John Deeres?

As an picture worth a thousand words...

John Deere:

https://www.deere.com/assets/images..._f13b7e02c23fb471304f803dc1a1acdd45bfdeaa.png

Gardner:

L

 

[menzies]

As an picture worth a thousand words...

John Deere:

https://www.deere.com/assets/images..._f13b7e02c23fb471304f803dc1a1acdd45bfdeaa.png

Gardner:


L

That's what I thought - I know which engine I would rather have on the water!

 

[RT Firefly]

Greetings,
Mr. L_t. I agree with your John Deere image but a Gardner would be more akin this IMO.

 

[menzies]

OK, back to the more "serious" conversation.

What did Northern Lights do to the JD to make them a Lugger, and is there any real difference between a JD 6068T and a Lugger 6068T?

Now don't be castigating me. I would really like to know.

 

[Sailor of Fortune]

Lugger always said their cooling system was superior.

 

[Insequent]

OK, back to the more "serious" conversation.

What did Northern Lights do to the JD to make them a Lugger, and is there any real difference between a JD 6068T and a Lugger 6068T?

Now don't be castigating me. I would really like to know.

According to some, Lugger did better marinisation of the tractor engine. eg better heat exchanger and oil coolers. When I re-powered at Port Townsend Luggers were not worth the additional cost over the JD 6068's. We did install aftermarket oil coolers and engine mounts.

My local dealer in Australia had a list of things he would do to the base engine from JD for marine installations, including things noted above but some other things as well. Due to JD giving exclusive rights to their stuff to one wholesale group in Australia, rather than cop an extra margin (and increase pricing to customers) he now sells Nanni John Deere. My 6068's were made in France anyway, so taking them down the road for Nanni to marinise is easy. My dealer says that Nanni have all the bases covered and he needs to do very little when he receives them to stick into boats.