Husky 357 Connecting Rod Bearing Condition

[Agrarian]

I am rebuilding a 357xp whose crankshaft bearings needed replacing. When checking over the connecting rod large end bearing, I see it has some "wobble". I am not talking about the freedom it has to move side to side on the bearing. I am talking about holding the large end centered on the bearing and moving the small end in a direction towards each end of the crankshaft.

It has about 0.090" of total travel at the extreme of the small end. Is that too much? I know that any radial slop is not allowed and this crank does not seem to have any. But how much wobble is ok?

There is one thread on here that talked about 2-3 degrees or as much as 5 degrees would be ok. I don't have the shaft in front of me but on a 3" rod, 0.1" of wobble would be about 2 degrees, on a 4" rod, it would be about 1.4 degrees. I'm guessing this rod is somewhere in that length range.

I checked the 3 Husky service manuals I have and they only talk about radial play.

Anyone know what is acceptable?

 

[sunfish]

I wouldn't worry about that little bit of wobble.

 

[Agrarian]

Happy to hear that but when do you worry?

 

[Ozhoo]

...when do you worry?

You don't worry about axial play, only radial play.

 

[blsnelling]

Even a brand new crank will have that kind of play. All you're concerned with is radial play.

 

[Agrarian]

You don't worry about axial play, only radial play.

But this is not axial play - axial play is the side to side play that a connecting rod has on the journal while it remains 90º to the bearing. This is holding the connecting rod anchored in the middle of the journal and wiggling the other (piston) end.

 

[Agrarian]

I dug up this info from a thread in 2009:

A tiny bit of side-to-side movement is ok, but anymore than about 2-3 degrees off center and you're looking at excessive slop. I've noticed that the bearing rollers wear on the ends first, so the side to side movement is the best indicator for me to tell about wear.

and this one:

No play up and down (radial)
OK to move side to side on rod
Lean- OK ( I talked to a tech that said something about 5 degrees)
Twist- not so good

I understand that this bearing is essentially floating and designed to allow for manufacturing and assembly tolerances by having axial and "wiggle" play. I picture this like the end gap on rings. Even new there is a gap and that is ok. But as it wears the gap grows until it is no longer servicable. I'm trying to understand when the crankshaft is no longer serviceable.

Am I getting concerned over nothing? Is it as simple as "If there is no radial play it is still good to use"?

 

[bmwpowere36m3]

I don't have the experience on these types of engines... but the play you're describing is a way we check for rod (big-end) play on car/motorcycle engines. All rods will have side-side play/clearance (slide). However if you hold the rod centered and rock the tip thats wear.

An example motorcycle spec is: 0.12" (rod is ~ 4.21" long).

 

[rmh3481]

Hold the crank in your left hand. Hold the rod in your right hand. Any up and down play is bad. Have you looked for a replacement crank yet?
Here is an aftermarket option that tends to hold up fairly well;
http://www.hlsproparts.com/Husqvarna-357-359-crankshaft-p/h35357.htm

 

[Agrarian]

Hold the crank in your left hand. Hold the rod in your right hand. Any up and down play is bad.

You are describing the test for radial play which I know is bad. I am asking about a different type of play.