While we're talking about rings

[ScottyHOMeY]

Chief's thread below caught my eye, epecially the responses about the differences in the way different rings wear in and seat.

I put new Firecraters and sleeves in my '47 BN a few years back. I had to leave the project set for a couple years, but kept the plugs in but loose (to keep the meeses out) and every few weeks pulled the plugs and spun the engine with the hand crank to keep it free and (hopefully) rust-free. Every third or fourth time, I'd shoot some oil into each cylinder before spinning her.

Finally got her all back together, painted and running last year.

The rings were chromed but I couldn't tell you if they were steel or iron underneath. My concern is that she still runs quite smoky, and I'm guessin' it's because the rings haven't seated. I run her pretty regularly just to keep the battery up and the oil dry, but I can't say she's worked under a load yet -- apart from about twenty minutes of draggin' my friend's tractor around trying to free up my clutch that stuck (another story, but fine now). Apart from that little exercise, she only has about twenty hours on the rebuild, none of it doing more than moving her own weight.

Any thoughts? Have I got a problem or do I just need to get the old girl out and work her some?

 

[Gary in da UP]

Having a dynometer for break in would be a beautiful thing , woudn"t it !

 

[JT]

Scotty,
Sounds like you just need to take the old firl out and make her earn her keep. Rings will not seat in real fast running under no load. If it has chrome rings, that is even more important to run it under a decent load to break them in.
Jim

 

[ScottyHOMeY]

That's what I was thinkin'. I might be able to come up with somethin' between now and then, but I've got a neighbor makes a lot of hay that I'll be rakin' for next summer. Not a lot else for ag around here.

Any idea of whether you can run one too long with no load to where the rings just won't seat?

 

[ScottyHOMeY]

Yeah, it would! With the F&Rs on the rear though, I've got an idea I'd start her from the ground and let her do her thing.

I hate bumps! ;8^)

 

[big hunter]

If I'm not mistaken most all of the "big truck shops" after they do a rebuild do a chassis dyno-break in...

 

[JT]

Probably not, but it can glaze the cylinder with prolonged no load running on a fresh engine rebuild.... You might ask around and see if any neighbors have a PTO generator you can put on it with a light load for a while to break it in.

 

[Anonymous-0]

for engine break in put a bush hog on the back and back it into a water hole or pond. you can load it up just like a dyno.

Have done so many times

 

[ScottyHOMeY]

I hear ya.

While runnin' the old darlin' just to keep her runnin', I've been blockin' off the grill to heat her up quicker. Might look a little silly runnin' up the road with the funny pages coverin' the grill, but I'm accustomed to scorn and derision. ;8^)

In the meantime I keep lookin' for a load to put on her, just tryin' to avoid the glazing. If the smoke doesn't clear up after giving her a real workout, I'm thinkin' I'll need to pull the pistons and put another quick honing on the walls of the sleeves and start over????

 

[JDemaris]

I'll have to plead ignorance here as to what exactly the Firecraters are. Do they boost compression? When I worked for Deere, we installed quite a few high-compression pistons that Deere sold as "High Altitude." We also used M&W high-compression pistons. With either of them, smoking was always more of an issue if the cylinder walls were not perfect. That's the way it works with any boost in compression. The higher the CR, the less tolerance for wear.
We quit using them early 80s since rebuilt engines did not last as long with hard farm work and detonation with regular gas was one of the issues. It soon became a "non-issue" since most farmers went over to all diesel - except for light work like raking hay.

Back to break-in and new engines. If all the machine work is high-grade from the start - very little break-in is needed. From there, the more imperfections, the more break-in needed since the metal parts have to wear into each other until good sealing occurs. In some engines - that will never happen - especially if the cylinder-walls are tapered or scored - or the piston ring grooves are too wide.

With your engine - I don't know exactly what you did. If you did a good quality bore job - and the pistons are good - then there's no real time limit on the break in - ecxept . . .
When parts break-in properly, wear almost slows down to a stop and friction is at a minimum. We've had engines that, instead of breaking in, wound up scuffing the cylinder-walls because the cross-hatch hone-marks were worn off before a protective glaze was created. The cross-hatch is needed to give oil a place to sit.
You also might be burning oil through the valve guides - which would really show up when throttling down - rather than when powering up.
If we had it at our shop - we'd tell you to beat on it like you're mad at it and see if it improves. We found that to break-in tractors we just rebuilt that lacked PTOs and could not be loaded on the dyno - we'd take them for a long ride on a long steep hill - going up. This gives you the ability to control the break-in load at different loads and RPMs without overloading the engine. Lug it down in a high gear a bit, then downshift, take the load off, and throttle it up.
What I have witnessed on some fresh rebuilds that were not broken in properly - is scuffed and scored cylinder walls - and piston rings that "walked" around the pistons until all the gaps lined up.

 

[Anonymous-0]

In my situation, I would just disk a field, but in your situation, I like the suggestion below to borrow, rent, or buy a PTO generator. Hook up your house or water well. Run her a few hours, then let her rest, then run her about 8 hours. Some honest work like this would do wonders for your tractor. If you cant get PTO generator, then look into someone who has a dyno. Tom

 

[ScottyHOMeY]

Thanks.

The Firecraters are a high-compression piston.

As far as assembly goes, they come with pistons matched to sleeves, and I'm a bit of a nut about keeping such jobs clean from the git-go, and have no worries about that.

On the one hand, I'm thinkin' it's just a matter of not havin' worked her hard enough yet. On the other hand, I'm a little worried that I may have busted an oil ring whilst poppin' the clutch tryin' to break it free.

Other'n that, pretty as she may be, I'm more than willin' to work her to get her runnin' right.

 

[trucker40]

You probly need to work it.You dont say if you ground the valves or had new valve guides.The valves can make a motor smoke as bad as rings can.
If you dont think its valves it could be a broken ring,or rings on the piston wrong,gaps lined up.Lots of things.

 

[trucker40]

You might end up needing to do that.I think if you find a ring or 2 thats broken you wont need to hone it.Also they have marks on the rings that have to be up when you put them on the pistons.It could make it smoke maybe if they are on upsidedown or gaps lined up and not even have a broken ring.It takes a while to wear the hone marks off the cylinder walls.

 

[fixerupper]

I always thought M&W made high compression pistons they called Firecraters as a trademark name. Do you mean I've been wrong all this time? Jim

 

[chuck craig insocal]

back in the days when i was feeding race motors we would enter some "BON AMI " into the air intake [beyond the air cleaner] to hasten the rings to break-in my .02 30 cc

 

[Anonymous-0]

Yes this will seat the rings quickly, but the cost is about 1/2 of the ring/liner life.