1973 kenworth

Some cool old trucks.

 

As a 2 stroke owner and user.... not all 2 stroke Detroits have that feature. Many have no clue how to even reset it lol. But that feature sure saves you from being in a castiron shower!​

 

Or they drove one somewhere for a company that never worked on them never maintained them and barely serviced them.

My pop had an old trackloader with a 271 detroit. His buddy had the exact same machine.

One day his buddies' brother got onto my dad's machine and when he pulled the throttle back and ran it he said oh my God what the hell did you do to this? Our machine won't run like this it won't push like this how did you get this kind of power out of this engine? What the hell did you do to it? Our machine is dead compared to yours.

And my father asked him when the last time the rack was set on his machine when was the last time the injectors were changed when was the last time the blower was rebuilt when the last time the valves were set. When was the last time the engine was rebuilt?

Their answer to my father was we have never touched it. Why would we? Thee machine starts and runs great.

That's the difference between running a fleet truck that has never been touched or having your own that you take care of and service.

 

I've seen them and heard the two cycle Detroit's before, but have little experience with them. I'm fairly certain the first number and letter (8v-92, 6v-92) are the number of cylinders, but what about the last two numbers? Does it have to do with displacement?

I've heard stories of them running backwards and running away until they fly apart.

 

Yes displacement per cylinder. 53, 71, 92.
The 8V92TA in one of my transtars is 736 cubic inches.

 

I don't know what it is about the two stroke Detroit I don't think any engine has had to put up with this much BS mainly from people that don't know what they're talking about.

The stories that you should be hearing are the incredible engineering Feats that made that engine run I think from the 1930s right on until the 1980s and I think maybe even today they still make two strokes for the military.

We should be hearing stories about how the 2-stroke Detroit is an engineering Marvel that a little teeny tiny engine puts out as much power as a much larger engine.

They were so brilliant that they made it such that the 71 series are all the same.

If you need a piston for a 71 series that's the same Piston from a 271, 371,471 671, 871, 12-71 16-71. The parts all interchange, therefore they manufactured less parts making it cheaper and easier to maintain. That is also true of the 53 series and the 92 series.

Being a two-stroke, they are the fastest starting engine. Nothing is easier to start in the cold weather and nothing is faster to start in the warm weather either.

I have an old truck with a 671 in it that sat for 10 years. I put a battery in it and that engine did not move even 1/4 turn and fired off.

Some people can hate them some people can love them but they just have the reputation of being the most durable engine that can take the most punishment and just keep going even when it's not even running right.

They really are something incredible and unique and part of our history if you just understand them a little bit.

 

Hey I'm not a hater of them. I just haven't been around them much. Place where I worked right out of high school had an old Terex loader with a two cycle Detroit, and as you said, it was probably the easiest starting diesel in cold weather. I think that was a four cylinder. What was neat was once it was warm, if you mashed the throttle, you'd never see any smoke out of it. Makes me wonder if it was a cleaner burning engine than everything else from it's time.

I do know a guy had a 6v92 in a truck that had sat for some time. He decided to sell it, and after sitting for about two years, it fired right up. He left it run for a bit, and went inside for lunch. When he came back out he tells me it was sitting there running wild. He tried to shut it off, but it kept going. Filled the hollow around his house with smoke, and finally died about half an hour after he tried to shut it off. He left it sit and cool down, started it and it ran fine. And that truck is still running today, doing site work at a local quarry.

So, no, I'm not a hater. Actually quite fond of those engines. Just never been around them much

 

I didn't mean to imply that about you personally. I was just talking about generally the silly stories that people talk about regarding the two stroke diesel.

One person that doesn't really know tells another person and that person tells another and another and another and someone else until there are things that almost become like an urban legend with a grain of Truth in it.

Like the leaking. The legend is that the Detroit's are terrible leakers they leak everywhere horrible engine.

If your engine is tuned up and serviced right and running right, you don't get a whole lot of oil that comes out of the slobber tubes. But again that's about maintenance.

You can also put a catch kit to catch whatever comes out so nothing is on the ground.

If there's a cover that's leaking just like any other engine you put a new gasket on it. Isn't that amazing? No more leaks.

I've seen plenty of bone dry two strokes in my lifetime.

Not to be redundant, but these engines just run so well and run so long and just keep going and going and going and going that the guys that mechanic on the fleet trucks would never fix anything. Change oil and filters get it out of here. Oil leaks in the 70s really didn't mean much. Oil was cheap so nobody fixed it. And the fleet drivers blame the engine.

Maintenance is everything.

And if the engine is tuned properly and maintained you'd be surprised how clean they burn.

With all of the years that those two strokes were in production, and they powered everything from trucks and buses to military vehicles and heavy equipment and generators and on and on and on and on and on.

When you look at it that way, it really has to be one of the most successful engine designs ever of all time.

And it's difficult to get stuck with a two-stroke Detroit, Because unless you have true mechanical engine damage, each injector is its own pump.

So if you went out with 8 cylinders and you had a problem on one bring it home on 7. No Central injection pump like Mack or caterpillar to leave you on the side of the road.

Maybe that's why the military used so many of them.







If they are tuned up and operating properly, you'd be surprised how clean they burn.