Twin City Engine

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007001.jpg
one bit of really interesting news is that WMSTR has recently aquired the original engine that came off the trencher thanks to Mark Peterson it was built by Twin CityTractor Company so on the December 10 work weekend at Larson it was disassembled by a crew of faithful volunteers this shot shows Vern N. and Jim B. getting ready to lift off exhaust manifold

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007002.jpg
Jim B. Vern N. and Ryan U. dicuss removing the valve train from engine

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007003.jpg
Mark K. is diassembling the crowd engine for the Osgood steam shovel which might be coming to show at some time in the future
more to follow ran out of time tonite

[40avery]

Work weekends at Jim's are always fun and interesting. The Twin City motor is really going to add to the trencher as a display. I have always enjoyed the sound of the TC motors.

[M Kerkvliet]

I looked at that picture of me for aver a minute trying to figure out what I was reaching for! The "mouse catcher" did not show up well in the light I am in right now! Kelly, Gary and I really did work hard on that engine, but Louie snaps the picture when I am petting a cat!:biglaugh:

Oh well... Shows my softer side for the ladies...:D


Work weekends at Jim's are always fun and interesting.

Where were you????? I was looking forward to visiting with you!

[M Kerkvliet]

I thought I would throw this picture in, since Louie was so busy taking pictures he could not be in any of them! He did do a lot of work on the engine on Saturday too.

Here they are getting ready to lift off the last cylinder.

http://i155.photobucket.com/albums/s317/mbkerk/louieworkedtoo.jpg

Looks like Vern N, Louie L, Donald C (hiding), Ryan U, and Bob C.

Another picture just for fun...

In this picture Klinger is describing to Gary Muhl how a crowd engine works (in between bites of cold pizza) while Jim Stewart and Kelly Muhl listen on...:biglaugh:

http://i155.photobucket.com/albums/s317/mbkerk/klingerpizza.jpg

[40avery]

Where were you????? I was looking forward to visiting with you!

I did not know it was a work weekend up there or otherwise I probably would have been there!

[Lee]

Is the trencher drivetrain also Twin City? The engine looks the same as the 60-90.

[M Kerkvliet]

Is the trencher drivetrain also Twin City? The engine looks the same as the 60-90.

I don't know about the drive train, but I asked Mark Pedersen about the engine, and it is not quite the same as the 60-90. The 60-90 was a 7¼ X 9 and this one is a 7¾ X 9. To save you the math that is 2546 cubic inches displacement! 424.3 cubic inches per cylinder! Next time I see Mark, I'll ask him about the torque!

One cylinder of that engine = almost 7 of my Geo Metro engines! :eek: One cylinder would hold 1.8 gallons of water!

Correct me if I am wrong on the numbers Louie...

[Jerry Christiansen]

Hi Mark and all,

Your calculations look correct.

Now if we know the operating rpm, we can calculate the cubic feet of air needed each minute. Using the CFM of air and a reasonable fuel to air ratio, we can calculate the gallons per minute(or hour) of fuel the engine should use at full throtle.

Later,
Jerry Christiansen

[cjmlarson]

Hi Mark and all,

Your calculations look correct.

Now if we know the operating rpm, we can calculate the cubic feet of air needed each minute. Using the CFM of air and a reasonable fuel to air ratio, we can calculate the gallons per minute(or hour) of fuel the engine should use at full throtle.

Later,
Jerry Christiansen


I was told that it operates at 600rpm

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007007.jpg
this is what cylinder #3 looked like when we got the head off being that all the pistons were stuck in the cylinders after we got heads off we laid the engine on it's side pulled off the oil pan took off the rod caps to get cylinders off the block

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007008.jpg
here we have Kelly M. Vern N. and Ryan U. taking off rod caps

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007009.jpg
another shot of Vern N taking rod caps off they were a little frustating to get off because each cap had a cotter pin to lock the nut on

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007010.jpg
last jug out and on it's way over to the press to push the piston out of the cylinder

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007012.jpg
Jim B. running press Vern N. Gary M. getting ready to catch piston when it comes out Kelly M. waiting to take it away

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007014.jpg
piston assembly after being removed from cylinder

[louie]

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007011.jpg
Wimpy A. has already started repirs on the engine he is preheating the exhaust manifold to weld cracks in it

[louie]

Is the trencher drivetrain also Twin City? The engine looks the same as the 60-90.
the drive train is manufactured by the buckeye trencher company I have found a web site that has some of the original sales brochures for several of the trenchers that the company manufactured will see if i can get it posted here at a later date

[CaseyD]

This is a super-neat engine. Thanks for the story, info, and updates!

[M Kerkvliet]

You small block Chevy guys are pretty proud of you're 4 bolt mains... This bad boy has 4 bolt rods!

http://i173.photobucket.com/albums/w54/louie14steam/saturday12-10-2007014.jpg

Great thread Louie! Thanks!

[CaseyD]

Now if we know the operating rpm, we can calculate the cubic feet of air needed each minute. Using the CFM of air and a reasonable fuel to air ratio, we can calculate the gallons per minute(or hour) of fuel the engine should use at full throttle.

I was told that it operates at 600rpm

Could you use that information to estimate the PTO HP?

[Tom Cwach]

These are from a MM power units brochure dated 1938.

[Jerry Christiansen]

Cody,

Yes, the horsepower of an internal combustion can be calculated by knowing engine specifications similarly to how the PLAN formula can calculate the horsepower of a steam engine. In both cases the calculated horsepower is the ideal or theoretical power. The useable or brake horsepower of the engine will always be less than the theoretical.

The rustyiron.com website has the formula below that will approximate the horsepower of a gasoline engine:

Hp = (volume of cylinder in cubic inches X rpm) / 13400

If the engine is a two cycle, 10000 is used in place of 13400.

The volume of a 7.75 X 9 cylinder is 424.6 cubic inches and the engine is rated at 650hp. Substituting those numbers into the formula gives us:

Hp = ( 424.5 X 650) / 13400

Hp = 20.6Hp

The formula predicts for one cylinder so the answer has to be multiplied by 6 resulting in about 124Hp. According to the table in an earlier post, with 62 octane gasoline the engine should produce 162Hp. In this case the formula has about 23% error! This engine must be more efficient than what the formula is expecting.

Now that the horsepower is known, fuel consumption can be estimated. One horsepower is equivalent to 42.4 BTU/min and one gallon of gasoline is equivalent to 129000BTU (depending on what grade of gasoline).

162hp X 42.4 BTU/min X . . . .1 gallon . . X 60 min =
. . . . . . . . . . 1 Hp . . . . . . . . 129000BTU . . . 1 hr . . . (the dots just make the fractions line up)

3.2 gallons/hr

The calculation above assumes that all the energy in the gasoline is changed into useable work. If the engine was 25% efficient it would burn 4 times the 3.2 gallons or 12.8 gallons/hr.


Later,
Jerry Christiansen

[M Kerkvliet]

These are from a MM power units brochure dated 1938.

Great scans Tom! Thank you very much for contributing...

Jerry... I am betting on the 12+ GPH number! I don't know how one would compute the efficiency of the engine, but I bet a lot of the fuel is given up for heat? In other words, there is a certain amount of those BTU's that are being burned up just to make the mechanical parts of the engine move (friction) and that equals heat.

Am I thinking correctly?

[Jerry Christiansen]

Hi Mark,

You are thinking correctly that friction takes a share of the energy in the fuel. A large amount goes right out the exhaust pipe with the hot air that is expelled.

Efficiency can be figured out by using a Prony Brake or other type of dynomometer. If the power coming out of the engine is known and the rate of fuel consumption is known, then efficiency can be calculated.

Later,
Jerry Christiansen

[GKarels]

I had an instructor in diesel school that discussed a one third split for heat generated.

1/3 of heat was expelled out the cooling system.
1/3 expelled out of the exhaust
1/3 was converted into usable power.

I do not remember if the topic at the time was gas or diesel engines, because we had classes for both. But I remember it bringing to light just how inefficient an internal combustion engine is.

[Eric M.]

Cody,

Yes, the horsepower of an internal combustion can be calculated by knowing engine specifications similarly to how the PLAN formula can calculate the horsepower of a steam engine. In both cases the calculated horsepower is the ideal or theoretical power. The useable or brake horsepower of the engine will always be less than the theoretical.

The rustyiron.com website has the formula below that will approximate the horsepower of a gasoline engine:

Hp = (volume of cylinder in cubic inches X rpm) / 13400

If the engine is a two cycle, 10000 is used in place of 13400.

The volume of a 7.75 X 9 cylinder is 424.6 cubic inches and the engine is rated at 650hp. Substituting those numbers into the formula gives us:

Hp = ( 424.5 X 650) / 13400

Hp = 20.6Hp

The formula predicts for one cylinder so the answer has to be multiplied by 6 resulting in about 124Hp. According to the table in an earlier post, with 62 octane gasoline the engine should produce 162Hp. In this case the formula has about 23% error! This engine must be more efficient than what the formula is expecting.

Now that the horsepower is known, fuel consumption can be estimated. One horsepower is equivalent to 42.4 BTU/min and one gallon of gasoline is equivalent to 129000BTU (depending on what grade of gasoline).

162hp X 42.4 BTU/min X . . . .1 gallon . . X 60 min =
. . . . . . . . . . 1 Hp . . . . . . . . 129000BTU . . . 1 hr . . . (the dots just make the fractions line up)

3.2 gallons/hr

The calculation above assumes that all the energy in the gasoline is changed into useable work. If the engine was 25% efficient it would burn 4 times the 3.2 gallons or 12.8 gallons/hr.


Later,
Jerry Christiansen


The formula is dead wrong; let me prove.

There is an 80 Horsepower Western engine at the Vista show. It definitely can produce its rated horsepower, because Western tested their engines at the factory before they shipped them.
Stats:
80 Horsepower
14 1/4" bore
24" stroke
200 RPM

Now for the numbers

Hp = (volume of cylinder in cubic inches X rpm) / 13400

Substitute the appropriate numbers

80=(3825.6975 x 200)/13400
80=(765139.5)/13400
80=57.1
No, wrong, do not pass go, do not collect 200 dollars. And this is the calculated power for a slow-speed, single cylinder engine from 1924? I think we have a problem here.

The 1/3 split is likely for a Diesel. Even modern automobile engines are only 25-30 percent.

[Jerry Christiansen]

Eric,

Thanks for the input about the formula. Some people are pretty generous with the word "approximate". Your numbers show about 29% error and my example had 23% error. I think we need to find a better formula!

As long as this got bumped up, any progress with the enigne?

Later,
Jerry Christiansen

[40avery]

Check this out for adding efficiency!

http://en.wikipedia.org/wiki/Crower_six_stroke