Load versus no load fuel consumption test.

Klass 44,
That's an International truck engine ... as in International Harvester. Probably considerably better for a boat than the Chrysler Hemi.

It is a heavy duty engine. Consider it is from 1970 and still working good.


Here is an album with a few videos of it running right after the rebuild.

https://photos.google.com/share/AF1...?key=NVZlQTNmblNxOXJUd1JHT3dMUDRCR0EtQ2ZmeGxR

I found out the gas in the boat over the winter went stale, about 35 gallons is in one tank, other tank is empty.
I think I should plan on not leaving any gas in the boat when it will sit a long time.
I switched over to the boat tank from my portable fuel tank and engine started missing and could barely run throwing up lot of smokey exhaust. Fuel decay is one reason I hate E10 gasoline. Due to ethanol, gas decays rapidly compared to before E10. You have to keep dosing it with Stabil and I neglected that. I can likely dilute it and run it in the car.

I did an experiment with this rebuild. Rather than buy new pistons, I sprayed the skirts with KG Nano Gun Kote blue.
It is a high temp phenolic resin with moly lubrication and I built up the skirts to go from .006 - .007 to .003 clearance. Cheaper than buying new pistons and I wanted it tighter, did not want any piston slap. Only way to tell how it does long term is time.

If it works, maybe next time I will ceramic coat the piston tops. That reflects heat back into power and keep pistons running cooler. ALthough the improvement is likely minor, it may help with overheating or detonation.

"did not want any piston slap. did not want any piston slap."

The usual is to have a machine shop knurl the pistons.

Quite cheap.

FF said:

"did not want any piston slap. did not want any piston slap."

The usual is to have a machine shop knurl the pistons.

Quite cheap.

Click to expand...

Still it costs money, and I like to experiment.
Knurling also does not last, don't know how long, but that is what I read.

My other engine the pistons were knurled, the knurls were worn away.
Knurling makes a small surface area of ridges.

I was wondering if it was factory, since all the parts were standard sized and marked with IH factory numbers on the bearings.

From a few years earlier my port rebuild, that one got new pistons.
Although, now maybe I could have just Gun Koted them, instead of paying $400 for a set. The contour tops are usually much more than the other flat top IH design, likely because the engines are less common, less demand for parts.

https://photos.google.com/share/AF1...?key=MXFfUjIzY0NXd080dWVyeTNQX0V3a2J2bWk3cGRR

717,
Amazing ..
You've got 260hp, I've got 40 and we've got the same transmission.
What's that rectangular thing on the big end on the con-rod? Counter weight? Oil splasher? I'm suprised the pistons have shch a short skirt. It was vouge in the day though. Crankpin has large OD. I agree w you about the knurling. I've heard it gives better lubrication though but small bearing surface and in your case on a very short skirt.

They are velvet drive 72C with 2.57 to 1 gears.

The big blob is odd. It can be ground to aid in getting the engine balanced.
It may aid the piston putting the weight offsetting to one side, instead of drilling offset pins, really just guessing. Short skirts less frictional loss same with thinner rings. These skirts are large compared with many gas engines today, but compared to diesels they are small. THe IH 392 pistons have an embedded steel or cast iron ring in the crown to help keep the piston in proper dimension when running under load.

bayview said:

All the design changes in the world will not offset the fact that diesel fuel has a higher specific energy content than gasoline.

Click to expand...

Yes, but not that much difference.

1 gallon of gasoline = 120,476 Btu
1 gallon of diesel fuel = 137,381 Btu (distillate fuel with less than 15 parts per million sulfur content)

Click to expand...

I think it has to do with at low speeds diesels are very lean burn because of the nature of the combustion being a compression ignition verse gas spark ignition has to remain at 14 to 1 homogeneous charge or it will miss fire.

However, they are now working on direct injection of gasoline into the combustion chamber and experimenting with finding ways to do this lean burn at low power demand.

Diesels as power demands increase they do burn more and more fuel. Maybe someday gas motors will be much more efficient heat engines, closer to diesel, All engines waste lots of energy radiating heat. Engineers are seriously making big changes with engines efficiency and gasoline engines are getting most of the research since governments say diesels pollute too much and gasoline can burn cleaner easier.

http://www.hybridcars.com/will-america-avoid-europes-clean-diesel-problems/
http://www.scientificamerican.com/article/why-volkswagen-declared-defeat-in-diesel-cars/