Engine Overhaul Kama 554

[psj12]

I have rebuilt hundreds of diesels and only balanced the rods on one. This was a special case where the rod for that engine (foriegn) was unavailable and a rod from a different model, similar engine was modified to work. We sent it and samples of our existing good rods to a balance shop. When we got them back they didn't even weigh the same much less balance the sam end to end. I ended up doing it my self using a very accurate scale and I am proud to say that engine is still running.

 

[Bob Rooks]

Gentlemen, FYI, this is considered a medium speed engine because it's rated HP is over 600 r/m. Slow speed engines develop maximum HP between 50 and 600 r/m, such as the Sulzer RT-flex60C. And I agree that the balancing exercise is unnecessary because the inertia forces just aren't there with this engine, but it's fun to watch.

 

[MtnViewRanch]

While it may be fun to watch, so much of it simply is not needed. Hopefully we will have a reality check before Rob actually starts on the engine and he ends up doing what is needed and not a bunch of unneeded race engine stuff.

 

[Bob Rooks]

While it may be fun to watch, so much of it simply is not needed. Hopefully we will have a reality check before Rob actually starts on the engine and he ends up doing what is needed and not a bunch of unneeded race engine stuff.

I agree Brian. He could blueprint, port & polish, CC, and balance and it won't make a noticeable real-world difference on this engine. Rob is a very capable person, and I'd hate to see any expectations shattered. But if he really wants to do it, he should go for it, but realize that there will be no payback for the extra time spent.

 

[PAGUY]

Guys - Maybe Rob wants one of those tractors that are turbo charged with two smoke stacks on either side of the engine and the capability to bring the front end off the ground when he gives it the juice.

Think how fast he could get his projects done with a tractor like that the work done in half the time it normally takes him.

What say ye Rob? Are you up for high powered tractor that burns rubber?

 

[3RRL]

lol...
My goal is to have end up with a good running and very reliable engine.
I don't want to build a "race motor". I'm going to do most of the balancing just because I know the stock motor may not be set up close to what it really should be. I've seen this time and time again on my inexpensive Chinese tractor. You do "get what you paid for" and I'm aware of this. A lot of this is because I don't mind going through with some of these things just for my own satisfaction.
It can't hurt.

I'm still waiting for the new crank to arrive.
I also ordered a gram scale online so I presume it will arrive this week too? I will have to make up that balancing fixture though. I've decided to balance the weight of the pistons and cranks pretty much the way that first video showed. Although you guys are probably right that the results might be indiscernible or even unnecessary, at least I'll know it's been done.

I'll be tearing down the tractor more this week.
Hopefully, I should have some photos by the end of the week some to show the progress. My main goal this week is to at least have the engine out of the tractor and mounted to the new engine stand. It will be a lot easier access to removing the rest of the engine parts. If the scale arrives in time, I can build the fixture for it too.

 

[TBDonnelly]

Rob, The West Coast Nationals tractor pulling event taking place during the World Ag Expo is calling YOUR NAME!

splash ｻ West Coast Nationals

You have four weeks to pull it all together. You can do it!!

Don

 

[greg_g]

...I know the stock motor may not be set up close to what it really should be. I've seen this time and time again on my inexpensive Chinese tractor.

Operative word being tractor. But consider that the FeiDong 95 series engine is licensed from Isuzu. Chip pointed out quite some time ago how impressed he was with quality of the FD95 series components. He should know, they were in his parts room right alongside the YangDong parts. My feeling is that you may have reached the point of diminishing return here.

//greg//

 

[SPYDERLK]

Rob, until today I had missed those links in my visits to the thread. I thot you were referring to a PM or something.

Do not do it like the 1st link - the uTube one. That one is wrong. It is substantively different from the others in that it never weighs the big end. Those rods may weigh the same, but the big ends dont and theyre the most important to keep the same as you home in on an equal weight set. Since the small end only [[~]] reciprocates, its weight is of little importance and the only reason to take weight off there would be to adjust a heavy rod with light big end. The key is repetitive end to end weighings ending with big ends and total weights the same. ... The truth of this is borne out by the below excerpt from the last link [hiliting mine].

"The requirement for equal linear and angular acceleration of the connecting rods is met by the symmetrical movement the engine provides to the rods. If all rods have the same center-of-mass and that mass is of identical amount, then by Newton's Third Law, acceleration forces caused by translation motion will equal.
The requirement of identical moment of inertia (rotational inertia about an axis of rotation) means that the way the mass is distributed with respect to the axis of rotation is important. All rods need to have identical radius of gyration. This is achieved by having identical mass placed at the identical distances from the axis of rotation (piston end). "
larry

I've decided to balance the weight of the pistons and cranks [pretty much the way that first video showed]. Although you guys are probably right that the results might be indiscernible or even unnecessary, at least I'll know it's been done.

Not a very good way, but it will be easiest.. and almost definitely closer than they are now.
larry

 

[dcyrilc]

Rob, The West Coast Nationals tractor pulling event taking place during the World Ag Expo is calling YOUR NAME!

splash ｻ West Coast Nationals

You have four weeks to pull it all together. You can do it!!

Don

Thank you! I needed a good laugh tonight.

...and I'm still chuckling.