Can I Turbo a Stock Diesel?

[kmacdonald]

Originally Posted by Dockhead

Wow, there must be some story behind that. Thread drift, but I'm sure it will be interesting for all of us!

No wonder he switched form flying to sailing.

[darylat8750]

Originally Posted by a64pilot

I’ve had three, and they were properly maintained. One in a single engined aircraft. However I will agree that the big commercial engines are extremely reliable. I don’t think the big motors have a TBO?
I can’t think of any other engine failures other than racing engines that I have ever had, and I can only remember wearing out two engines.

My cousin runs big Cat engines on dredges and the budget is based on 20,000 hours between major overhauls. He expects some fuel injection service expenses before 20,000 hours but if it is more than injectors and possibly a fuel pump rebuild he gets cranky.

[Dockhead]

Originally Posted by darylat8750

My cousin runs big Cat engines on dredges and the budget is based on 20,000 hours between major overhauls. He expects some fuel injection service expenses before 20,000 hours but if it is more than injectors and possibly a fuel pump rebuild he gets cranky.

Are they turbocharged?

[newhaul]

Originally Posted by darylat8750

My cousin runs big Cat engines on dredges and the budget is based on 20,000 hours between major overhauls. He expects some fuel injection service expenses before 20,000 hours but if it is more than injectors and possibly a fuel pump rebuild he gets cranky.

that is roughly equal to a million road miles so there is something to be said for running at optimum engine output rpm for the life of the engine. Natural or turbo.

[ErikFinn]

Thread drift, no pun intended, you could just get an old quarter million mile Mercedes diesel engine, put a turbo in it and I reckon you'd have enough power..

Diesel Fury: The Black Smoke 300td Wagon - Speedhunters

Oh wait, what did they say about the hull speed again..?

[darylat8750]

Originally Posted by Dockhead

Are they turbocharged?

yes


I agree with A64 about turbine engines. I would rather fly behind 1 PT6 or JT8D than two of any piston engines.


On the subject of same engine family turboed and NA. My little tractor is sold with basically the same engine 60hp NA and 73 hp turboed. They look the same on the outside and the manifolding is easily exchanged but the compression ratio is slightly lower and the exhaust valves are sodium filled on the turboed engine. In my case I operate the tractor at 8800 feet elevation so naturally aspirated it is only making around 40HP. I put the turbo on it just to get back to the rated hp an didn't turn up the fuel flow at all. The increase in torque was very impressive.

[Cheechako]

Turbos are hard on engines, more problematic, and usually done to get more HP out of smaller, already designed engine. Why would you? A diesel mechanic once told me: "buy an engine (that fits your HP requirements) which is the lowest HP that manufacturer makes for that block design, for longevity and reliability"

[kmacdonald]

Originally Posted by Cheechako

Turbos are hard on engines, more problematic, and usually done to get more HP out of smaller, already designed engine. Why would you? A diesel mechanic once told me: "buy an engine (that fits your HP requirements) which is the lowest HP that manufacturer makes for that block design, for longevity and reliability"

I agree. That's how the manufacturers rate their engines also. For a given block, the lower HP versions are continuous duty or commercial and the higher HP versions are recreational use only. For our purposes, I think 50HP/liter displacement is the limit for reliability and longevity. Most small sailboat diesels are around 25HP/liter in NA versions only. I don't think I'd rule out a turbo engine for a larger sailboat but wouldn't want the added maintenance of after coolers.

[a64pilot]

Originally Posted by Dockhead

Wow, there must be some story behind that. Thread drift, but I'm sure it will be interesting for all of us!

This airplane, my design, an Experimental design at the time and had a Walter M701 turbine in it since the new GE H80 engine didn’t quite exist yet, they are nearly identical engines, except for the guts.
The Walter is a wimp compared to the GE so I would push the N1 speed to max continuous which was 101.5% and leave it there.
Anyway I had left Oshkosh from the big yearly fly in and just gone “feet dry” from the big lake, one of the Great Lakes, unsure which and had just come up Flight following with Center. (Chicago wouldn’t talk to me, too busy).
Engine went pop, ITT through 1000 and flames from the exhausts, Maydy, Mayday, etc., I was able to glide down to a little airport where I made a nice landing and even coasted off the runway to the taxiway, where a few minutes later, every emergency vehicle I think within 100 miles met me, and we looked at each other through a locked gate.
See since 911 all airports have to be secured, and none of the cops or Firemen had a key.
GE never would tell me what happened, but I’m certain the gas generator let go. We changed the engine design then too and the prop as the Avia prop that was on it at the time didn’t feather at engine failure, it was a double acting prop, which meant that it took oil pressure to feather. GE changed the design of the prop Governor and the airplane was certified with a Hartzell, which will feather at a loss of oil pressure

[a64pilot]

Originally Posted by kmacdonald

I agree. That's how the manufacturers rate their engines also. For a given block, the lower HP versions are continuous duty or commercial and the higher HP versions are recreational use only. For our purposes, I think 50HP/liter displacement is the limit for reliability and longevity. Most small sailboat diesels are around 25HP/liter in NA versions only. I don't think I'd rule out a turbo engine for a larger sailboat but wouldn't want the added maintenance of after coolers.

Agreed my 4JHE for example same block covers from my 44 HP to about 100 HP, only getting 44 means way less stress, and way ,longer life on average.
Your right about aftercoolers too, most call them intercoolers, but they are really aftercoolers.
What concerns me is they are often raw water cooled, let one wear out like a heat exchanger for example, and your engine is sucking raw water into it, which of course would be very, very bad.

[Dockhead]

Originally Posted by a64pilot

This airplane, my design, an Experimental design at the time and had a Walter M701 turbine in it since the new GE H80 engine didn’t quite exist yet, they are nearly identical engines, except for the guts.
The Walter is a wimp compared to the GE so I would push the N1 speed to max continuous which was 101.5% and leave it there.
Anyway I had left Oshkosh from the big yearly fly in and just gone “feet dry” from the big lake, one of the Great Lakes, unsure which and had just come up Flight following with Center. (Chicago wouldn’t talk to me, too busy).
Engine went pop, ITT through 1000 and flames from the exhausts, Maydy, Mayday, etc., I was able to glide down to a little airport where I made a nice landing and even coasted off the runway to the taxiway, where a few minutes later, every emergency vehicle I think within 100 miles met me, and we looked at each other through a locked gate.
See since 911 all airports have to be secured, and none of the cops or Firemen had a key. Attachment 162421
GE never would tell me what happened, but I’m certain the gas generator let go. We changed the engine design then too and the prop as the Avia prop that was on it at the time didn’t feather at engine failure, it was a double acting prop, which meant that it took oil pressure to feather. GE changed the design of the prop Governor and the airplane was certified with a Hartzell, which will feather at a loss of oil pressure

Great story!

[a64pilot]

Previous life, all better now

[Dockhead]

Originally Posted by a64pilot

Previous life, all better now

I don't know; looks like great fun to me.

I've dreamed about flying since early childhood, a dream which now looks like will have to wait for another life.

I did spend a lot of time in the right seats of a Pilatus PC-12 and a Raytheon Premier flying all over Eastern Europe, Russia, and Siberia on business. I wasn't allowed to touch the controls, though These planes belonged to one of our investors.

I actually bought my present boat with money I had saved up to buy a Citation with, which until the 2008 financial crisis I thought I could use in my business.

I lust secretly after a Diamond DA-42 with the diesel engines. Wow, what one could do with one of those. I like to read the Diamond technical manuals sometimes on long flights. But I don't have nearly enough time or money to even do the sailing I want, much less add another time consuming and expensive hobby, and I'm not going to give up sailing in order to fly, so it's just not in the cards

[a64pilot]

The Pilatus is a wonderful airplane, I’d rather have one than a King Air myself, and if I had that kind of money, it’s the airplane I’d want as it has great short field capability.
The Diamond Diesels are horrible airplanes in my opinion, slow and no useful load and two engines to fail, I’d much rather have a Cessna 210 myself, their only use to is get a twin engine rating, something I never did, cause I knew I’d likely never own a twin.

Best thing to do in my opinion is to set aside a couple of months to get your private in a C-152 or a C-172. Now the trick is to take is seriously and work at it to get it done, you have to fly three or more times a week.
Most people never finish, they fly every now and again and mostly rehash what they have forgotten to get back to a basic level but don’t progress, and eventually give up.
I had a rich Uncle pay for my ticket and of course it was my job to learn.
Most Civilians don’t take it seriously, it to them is recreation and not work, so they never finish. You need to consider it like a College course, go in knowing that it’s work, and sometimes it’s not always fun, it is rewarding though, just training if it’s good, may not always be entertaining.

Most of my Civilian flying so did myself was a little bush plane, a Maule.
This was it years ago camping at Sun-N-Fun

[Diesel Bill]

When I went to school for the Caterpillar 3208 series back in the late 1970's the engines were naturally aspirated and made somewhere around 200 H.P. They were used mostly in city tractors pulling 27 ft box trailers and school buses. They were a so-so engine for reliability and had some problems with the electronically controlled, hydraulically activated E.G.R. system. That's right, an exhaust gas recycle system on a diesel engine.
Now take these engines and add turbos, inter and after coolers and boost them to over 400-500 H.P. and you have a sport fisher or power yacht that can do 25-30 kts.
at W.O.T. They just don't hold together for long at this kind of output.

When I went to school for Detroit 71 series I got into an argument with the instructor over the parasitic loss of the Roots blower. He said they added power and I said they consumed power. As some one said a few pages ago the engines can't run with out the blower as every down stroke on a 2 cycle is a power stroke and Detroit 71- series uses the blower to scavenge and sweep the cylinders at the lower cylinder bores through the
ports which are pressurized by the blower pushing air into the air boxes.
The blower consumes approximately 25-30 H.P. to move the air required to run the engine. When Johnson and Towers started putting turbos on my beloved 6-71's and pumping 400-500 H.P. out the flywheels I knew they were selling high power at the cost of longevity and reliability.

When Dodge started putting the naturally aspirated 5.9 Cummin's engines in their pickup trucks they were so under powered that drivers pulling a trailer through Denver, Colorado didn't dare stop on the assent up the mountains, because the couldn't get moving again. Only after adding a turbo and then intercoolers did they become a desirable truck in the mountain states.
So yes, turbochargers do add considerable power but using any engine at full power output will shorten it's service life whether turbo or N.A.