Perkins Questions

Almost bought a 1979 Mainship 34 with a turbo charged Perkins 6 cylinder. Deal fell thru, then i just heard to stay away from the turbo Perkins but go with the naturally aspirited. Any thoughts, ides, on normal versus turbo for the engine platform??
Thanks in advance..........frank

My last boat, a 1977 42' Californian has twin Perkins T6.354(MGT) 185 horsepower engines (high output turbo version). My current boat, a 1981 42' Hardin Europa Trawler, has twin Perkins 6.354(M) engines (naturally aspirated, no turbo).

Having owned the platform with and without turbos, I am actually pretty indifferent. I certainly wouldn't avoid a boat because of the turbos. Not one bit. And, I don't regret having bought my current boat without them. Not at all.

On the plus side, on the rare occasion where I wanted to trade a whole lot more fuel consumption for a little more speed, the turbos could push my trawler hard enough to make an impressive bow wave and squeeze out another couple of knots. But, moderating that gain, it was a huge difference in fuel consumption for a relatively small gain in speed.

On the flip side, when I was in the salon above the engines versus up on the flybridge, I found the high pitch turbo whine to be a bit annoying. And, the turbos are an expensive part that, like anything else, has a lifetime. They are relatively easy to pull out and relatively cheap and fast to have rebuilt almost anywhere -- but eventually they'll need to be replaced, and they aren't cheap. I think something like $1100-$1500.
They also got crazy hot, which I didn't like. And, like any other part, not only is the part, itself, a potential source of failure, but so is the interface, e.g. the turbo-to-interface gasket can leak as can the interface-to-block gasket, the oil hoses, etc.

But, those down sides should be taken with a very, very heavy dose of moderation. The whine wasn't really that loud and no one else but me seemed to notice it. I am just well-known to be particularly sensitive to high pitches. The potential expense of the turbos is heavily moderated by the fact that they can last decades between rebuilds in recreational boating uses and can often be rebuilt multiple times before needing to be replaced. Compatible name-brand turbos, e.g. from Holset, are readily available, both new and rebuilt, so there is no problem replacing them. And, there are Chinese agricultural manufacturers that make them for Chinese tractors and are available via eBay and Alibaba, and some have reported that they cost $300-$400 and have lasted 1000+ hours and counting (I can't offer any personal experience on that one -- given that option, I decided to paid up for the Holset).

Also -- and I put this last because you really, really want to check this with someone smarter and who knows more than me -- my understanding is that, in the 6.354 series, the turbos make more horsepower, but do it at lower RPMs. As a result, depending upon the transmission gearing, the props can be bigger and have more pitch, resulting in a lower RPM cruise speed and less engine noise. (I think max horsepower is @ 2400rpm vs 2800rpm)

Having said that, I am still learning my new boat, don't know the prop pitch, and haven't exactly figured out the sweet spot, yet, so I can't compare. In practice, all I can say is that, my old boat WOT under load was about 2400 and cruise for me was 1900-2000 or so.

At any rate, I hope this helps!

-Greg

Fourboat said:

Almost bought a 1979 Mainship 34 with a turbo charged Perkins 6 cylinder. Deal fell thru, then i just heard to stay away from the turbo Perkins but go with the naturally aspirited. Any thoughts, ides, on normal versus turbo for the engine platform??
Thanks in advance..........frank

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Who did you "hear" this from? Possibly a reference to the Perkins engines with manicoolers. These engines need a good look by an experienced guy, if bad then price the offer lower to accommodate a new set of manicoolers.

GK pretty well summed it up otherwise.

My HT6-354 Perkins (T stands for turbo) had 20,000hrs on it when I rebuilt it.
Wish I'd never sold that boat. I'm sure it could have gone another 10,000 but I had the time so I rebuilt it due to a very, very slight slap in #6

The issue with the older turbocharged Perkins is the raw water cooled intercooler and exhaust manifold. They are both cast iron and do not last all that long in salt water.
You can eliminate the intercooler, but you still have to deal with the exhaust manifold.

I think all of the Perkins 6.354 series have the raw water cooled manifold. What I can say is that my current 6.354(M) does, as did my T 6.354 (MGT).

It does really seems like a silly idea to have hot raw water going through raw metal. I'm surprised they did it this way and no one has improved upon the design. But, there might be reasons w.r.t. cost or metallurgy that I just don't understand.

The thing I can say about the manifolds is that they do seem to last many years to decades in practice, they aren't super expensive, and they are readily available. I'd think they'd rot faster, but when I looked at boats -- many were original or had been replaced only many years earlier and were still working fine. And, in the boat in which I replaced them, they'd lasted 2000+ hours and nearly 40 years. Of course, I did also see boats where they'd rotted out and sure were making a mess!

On my old boat, with the T6.354(MGT) I replaced both manifolds. I think they were about $750.00 each and bolted right on. There is normally easy access to the top of the engine in a boat. No big deal.

As for the intercooler, it is only an issue on the T6.354 (MGT) version of the engine. The design on the 6.354(M) and T6.354(M) don't require the old "breadboxes". And, indeed, these are hugely expensive parts. They list at about $3,500. The good news is that they are readily available -- Orca makes them (maybe among others) and they sell through any number of distributors. The replacement also went in pretty smoothly, it was a good fit in all respects, but there was a lot of plumbing involved.

In my old boat with the T6.354(MGT) engines, I did spend, including mounting hardware and gaskets, about $13k on parts to replace the manifold, heat exchanger, intercooler, header tank, side plate, and oil/trans cooler. This was for two engines and included all the related details.

But, don't let that number scare you. It was the "replace everything associated with salt water, down to the bolts" number. In my case, it wasn't something that was a surprise. Nor was it something that I had to do. I could have replaced the side plates on the intercooler, boiled out the other coolers, and kicked the can down the road for a few more years or more. And, it wasn't a normal situation -- I bought a boat that had been a "slip live aboard" for a decade or so, where there was just enough idling of the engines to keep the salt water inside everything rotting it away. My goal for that boat was to buy a boat with good bones (and bad meat) with the intention of renewing everything and so I did. (I did pumps, injectors, exhaust pipes, fresh and raw water pumps, etc)

It turned out to be a great boat. I learned a TON. Among the thing I learned is that rehabbing a boat is a labor of love. Financially, I'd have been better off buying one in better condition and doing less. But, I learned a ton more about boats doing what I did, so I chalk it up to the high cost of an education.

One thing I learned is to really look at what is there. Some of the parts that came off were total wastage. Others were in need of maintenance but basically still good. Some, very oddly, were brand new. I already had the replacement heat exchanger, header tank, and manifold for the Perkins 4.107 based generator in an online shopping cart when I went to the boat to double check part numbers -- they turned out to be essentially brand new, even after disassembling the heat exchanger and scoping out the manifold and tank. Why? I dunno'. The generator didn't even run due to a controller problem. Perplexing. It must have died the day after the upgrade or something. The problem with the controller -- was one bad resistor.

For Perkins stuff you can get almost anything from the usual suspects:
-- S & W Diesel in Los Angeles [Call (310) 835-3155, they are old school]
-- TAD Diesel in Virginia [http://www.tadiesels.com/]
-- Foley Engines in Massachussets [https://www.foleyengines.com/]
-- www.Parts4Engines.com in Britian
-- www.mrcool.us [(866) 726-2665]

For diesel injectors and pumps, almost anyone can do them, but I do recommend the person who did mine and sells a bunch on eBay:
-- Diesel Injection Service in Wilmington, CA [Call Armando, (310) 200-9056]

No real difference in fuel burn, more power, same raw water cooled manifold and seem to hold up @ the same rate.

I have a 1979 mainship with a Perkins 165 and don't have anything to say or warn you about. A little extra high pitched noise with the turbo but I stay out of boost(under 1500rpms) while in the cabin to cut down noise.

gkesden said:

It does really seems like a silly idea to have hot raw water going through raw metal. I'm surprised they did it this way and no one has improved upon the design. But, there might be reasons w.r.t. cost or metallurgy that I just don't understand.

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By the late 90s Perkins Sabre's new marinization designs had gone to coolant cooled manifolds.

gkesden said:

It does really seems like a silly idea to have hot raw water going through raw metal. I'm surprised they did it this way and no one has improved upon the design. But, there might be reasons w.r.t. cost or metallurgy that I just don't understand.

The thing I can say about the manifolds is that they do seem to last many years to decades in practice, they aren't super expensive, and they are readily available. I'd think they'd rot faster, but when I looked at boats -- many were original or had been replaced only many years earlier and were still working fine. ]

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Mine is original and holding up.

They are expensive but I think thats more of a supply problem. If perkins still made enough/supported the old girl they'd be cheaper. It's also very simple and I also suspect when designed they didn't account for 50 years later supply problems.

A good practice could be a flush port with fresh water like with outboards but probably not needed.

In the late 90s when I still had the old T6.354 exhaust manifolds cost $2100 plus shipping from England IF they had any in stock.
I know of 7 boaters (all Mainshippers) who had their exhaust manifold fail.
In 4 cases they failed on the outside, the owners spotted the leak, and they got them repaired or replaced.
The other 3 lost their engine immediately (as in blown) as they failed internally and hydrolocked the engine.

I advise to keep an eye on your manifold.

Whoa guys ! many of you are talking of engines over 40 yrs old and expect forever without replacement parts. Try a Volvo and see how you get on 40 yrs later.
The company who made the original Perkins 6354 marinization parts are still in business and are called ejbowman.co.uk There's also a company called Parts4engines.com who make the OE parts for Perkins and if you need hands on guys then you need to talk to data@lancingmarine.co.uk.
Whatever you do, you cannot in all honesty say you don't have worldwide support from Perkins, a British designed and built product, don't settle for second best.

Perkins is Massey-Ferguson farm tractor, and all non-marine parts up to and including rebuilt engines are available from Agco dealers.
https://www.agcopartsandservice.com/

The manifold can be changed to fw cooled. The manifold is the last place the coolant passes thru before the heat exchanger.
If you need a new manifold:Online Catalog

As I mentioned in an earlier post the company who originally, and still do, supply Perkins with all types of manifolds, heat exchangers etc for marine and the military are called www.ejbowman.co.uk and being British they are happy to ship worldwide. I've found them very helpful and customer orientated over the years.

Irish Rambler,

I can also offer that when the prior owner rebuilt both of the engines in my boat in 2014/2015 he converted from separate heat-exchanger+header+manifold to a Bowman combination unit and it reportedly was straight-forward to install and seems to work well. I think he ordered it from TAD Diesel in Virginia (I'd have to look back at the receipts). But, the unit and whole kit was put together by exactly the folks you recommend -- I'm guessing TAD Diesel is just a US-local dealer.

gkesden.
I must admit that I like the Bowman system as its a simple direct fit will less extra plumbing. I've seen a few with separate systems and I prefer to keep it simple.

Highly recommend Marine Exhaust Systems of Alabama Marine Exhaust Systems of Alabama, Inc.

I purchased 2 exhaust manifolds for 6.354s from them for a fraction of lowest price anywhere else. The owner is a delight to deal with and (much to his wife's annoyance) reachable 365 days a year.

Rossland said:

Perkins is Massey-Ferguson farm tractor, and all non-marine parts up to and including rebuilt engines are available from Agco dealers.
https://www.agcopartsandservice.com/

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Yup, back in the day, I pulled a 6-354NA out of an 1105 Massey and stuck it in a little steel tug. Bought a water cooled manifold to do away with the dry stack and it worked super.

Lady Sue

1982, Mainship I

...goes into the water tomorrow. Cheesequake Creek off Raritan Bay. Our 28th year together. Her T63544 has 4000 hours. There is a point to every view expressed, good and less, but I did replace the Turbo for $1200 2 years ago. She gets a new impeller every year, and an oil change every 50 hours, needed or not. I usually clock a bit over 100 hours on her. My "personal motor" has 85 years on it and I expect the Perkins to outlast my sailing days.

If Mainship knew how to fiberglass the bridge (They didn't!) the boat would be indestructible...and Mainships of the '77-83 vintage are lovely to look at, aren't they?

Be glad to answer any questions: sue46jim@gmail.com.

Jim Ferry

All the original Bowman heat exchanger parts are available from ASAP -Supplies, and at very reasonable prices. I just bought the two different rubber end caps for $90 AUD, and that included shipping.

Whole re-worked heat exchangers and parts are available from Tad Diesels:

TAD for Perkins Diesel Heat Exchangers, Perkins Marine Heat Exchangers, Perkins Diesel Parts, Perkins Engine Parts

I have a normally aspirated 6.3544 in Sea Biscuit; 1,250rpm pushes her along at 7kn in flat water. The engine sounds amazing, and mine was a factory rebuild, purchased locally, and now has about 250 hours on it. I know it will outlast me.

We had a 42 Hershine /Jefferson for 12 years that we lived aboard in the San Francisco Bay and cruised both coasts with. It had Range 4 200 turbos in it. They were completely reliable and only required to be preventively maintained.
My real question is do you really want a Mainship? They are not trawlers and only suitable for lakes and rivers as well as the protected parts of the ICW.
They steer like a drunken sailor due to poor hull design and tiny rudders. They are outright dangerous in a following sea as they want to pitch poll.
I would expand my search to a real trawler if I was you.

Dealing with my T6.354 Perkins

The intercooler on my Apollo 32 with it's 1982 T6. 354 Perkins is cracked and I can't imagine bothering to replace it given that I rarely run the engine over 1,600 rpm. I did replace the cast iron exhaust manifold with a stainless steel unit from Marine exhaust Systems in Alabama and the turbo adapter and dry elbow and wet elbow with stainless steel from Atlantic diesel.


I simply did not want the uncertainty of the cast iron that one could never tell when it was going to fail, or replacing the manifold every 4 years as preventative measure.


With its age and over 4,000 hrs. the engine burns no appreciable oil and delivers fuel consumption of ~1 gallon/hr. @ 8 knots. I think it's a great, simple and reliable unit that will likely outlast my days with a boat.

Kit_L said:

All the original Bowman heat exchanger parts are available from ASAP -Supplies, and at very reasonable prices. I just bought the two different rubber end caps for $90 AUD, and that included shipping.

Whole re-worked heat exchangers and parts are available from Tad Diesels:

TAD for Perkins Diesel Heat Exchangers, Perkins Marine Heat Exchangers, Perkins Diesel Parts, Perkins Engine Parts

I have a normally aspirated 6.3544 in Sea Biscuit; 1,250rpm pushes her along at 7kn in flat water. The engine sounds amazing, and mine was a factory rebuild, purchased locally, and now has about 250 hours on it. I know it will outlast me.

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Thanks for the reply. Valuable info. Your boat is a beauty!
JJF

The Sally Ann said:

We had a 42 Hershine /Jefferson for 12 years that we lived aboard in the San Francisco Bay and cruised both coasts with. It had Range 4 200 turbos in it. They were completely reliable and only required to be preventively maintained.
My real question is do you really want a Mainship? They are not trawlers and only suitable for lakes and rivers as well as the protected parts of the ICW.
They steer like a drunken sailor due to poor hull design and tiny rudders. They are outright dangerous in a following sea as they want to pitch poll.
I would expand my search to a real trawler if I was you.

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As a Mainship owner, I agree with most of your observations: They are not blue sea trawlers, and the do not like following seas; however, they are excellent at what they were built for: comfort, economy, near shore coastal cruising--I've taken mine from NY harbor to Cape Cod, Miami, and points between. They handle rough water 4-5 foot seas, but depending on whether you are nosing into it or running ahead, you can get a good shoulder workout! I just love burning a gallon and a half diesel for hours on end at nine knots, don't you?
JJF

Tiffany said:

The intercooler on my Apollo 32 with it's 1982 T6. 354 Perkins is cracked and I can't imagine bothering to replace it given that I rarely run the engine over 1,600 rpm .

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If the crack allows water to migrate from the wet to the air side you could have an issue. Not sure how limiting to 1600 RPM would prevent this.

Many Perkins engines have bitten the dust due to salt water intrusion through a faulty after/inner cooler. But I don't know your manifold and cooler setup so may be off base.

sunchaser said:

If the crack allows water to migrate from the wet to the air side you could have an issue. Not sure how limiting to 1600 RPM would prevent this.

Many Perkins engines have bitten the dust due to salt water intrusion through a faulty after/inner cooler. But I don't know your manifold and cooler setup so may be off base.

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Sunchaser, The intercooler is not receiving raw water, so the charge air is not receiving that increased horsepower benefit, so also no wet to dry side problem. The setup was apparently changed by the [previous owner over the 20 year period of his ownership.


Once I push above 1600 the semi displacement hull is trying too hard to lift itself out of the water at 12 knots. Cheers, Doug

Not so

Fourboat said:

Almost bought a 1979 Mainship 34 with a turbo charged Perkins 6 cylinder. Deal fell thru, then i just heard to stay away from the turbo Perkins but go with the naturally aspirited. Any thoughts, ides, on normal versus turbo for the engine platform??
Thanks in advance..........frank

Click to expand...

Ran 2 6354T for 26 years - unbelieveably reliable-never a turbo prob! Kept oil and fuel real clean - not much else

Over the years we ran the Perkins P6's in agri machinery and the later 6354 and 4236's in both turbo and non turbo versions depending on their usage.
A turbo engine of any manufacturer is not happy running at slow speeds all day every day because they need to run under load and hot enough to be effective.
The secret of long turbo life is using the correct grade of oil for turbo engines and of course normal preventive maintenance.
When starting, don't start at a high throttle setting, as soon as it fires let the engine run at a fast tick-over for a few minutes then you can work it hard all day, when you wish to stop the engine let it idle for at least 5 minutes to allow the engine to cool slowly and relieve the thermal stresses around the turbo/cylinder head.
Just a little TLC and the engine will virtually outlive your use.
I've just sold a 40 year old boat with the original 4236 engine which never had the head off, it injectors and pump overhauled and 1 new water pump, oil pressure still high, starts first time.
I cruised it up the Western Isles of Scotland, around Irelands lakes, rivers and canals, over to England, around European canals and down to Spain and back so it was no harbour hogger. Brilliant engine and never let me down. Thank you Frank Perkins for a great engine.

lady sue said:

As a Mainship owner, I agree with most of your observations: They are not blue sea trawlers, and the do not like following seas; however, they are excellent at what they were built for: comfort, economy, near shore coastal cruising--I've taken mine from NY harbor to Cape Cod, Miami, and points between. They handle rough water 4-5 foot seas, but depending on whether you are nosing into it or running ahead, you can get a good shoulder workout! I just love burning a gallon and a half diesel for hours on end at nine knots, don't you?
JJF

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Autopilot baby!

As to the boat not being a bluewater setup.. My thoughts are that it falls down to the type of owner who buys them. A typical mainship is setup for comfort cruising/dock living.

Going from there the Mainship tends to dislike a following sea and with a full keel she'll rock and roll around. The boat will handle open water crossings just fine but i'm not sure the captain will.

My MK1 has the 160 perkins and they built them all the way up with 240hp. While I enjoy the 7 knot economy I do believe this boat performs better with higher hp as a planing style boat(around 15 knots). If you are able to run around 15 knots the following sea becomes mostly a head sea.

Keep in mind this is the same hull as the 35 henriques maine coaster which has an excellent reputation as a sportfish/downeast boat. The 35 henriques was either single or a twin engine hull with most being twin volvo 165's. Many people have upgraded HP and the most i've seen is a single cummins 425. The keel was slightly modified(shortened slightly) but in effect a mainship 34 below the waterline. Same issues in a following sea but a well regarded "canyon boat" for running ~100 miles offshore.

Here's a 35' Henriques hull showing the difference in the keel.

We hired a mechanic to come fix our Perkins 6.345m.. Well he took it apart and now we can’t get him to answer the phone. Does anyone have pictures, diagrams, or a link to manuals? Heck even a video of yours. We are mechanical but first diesel for us and I can’t find anything on this engine! Any help is greatly appreciated!