Big end Rod Bearing Play

[94BULLITT]

How much side to side play is allowable in a big end rod bearing? I did not see a spec in a service manual. I'm working on a TS420.

 

[jmssaws]

Side to side is irrelevant.
Up and down is all that matters

 

[junkman]

If its over 1/4 inch maybe replace it .

 

[94BULLITT]

Ok, thanks.

I can't feel any up and down play. I guess the rod has to be centered on the bearing or it has what feels like excessive play.

 

[94BULLITT]

Now I need to figure out if it is worth fixing. I need a cylinder. The plating is chipping off of this one.

 

[Al Smith]

What you need to do is check how much tilt the crank bearing has .Case in point my neighbor had some Makita ( Dolmar ) his buddy strong armed the bar nuts and trashed the crankcase . I turned him on to Scott at Chainsawr where he got the cases and it came with the crank .I told him to use the old crank which had no tilt .He didn't, tossed a chunk of the bearing cage up through the transfers nicked the piston .I saved it ,new ring ,some creative work with a file on the ring land .Could have been very bad

Funny part of all that was he had bought a low hour Stihl 290 from a dealer.Nice shape but once I got the old Dolmar/Makita up and running it ran circles around that nice shiny Stihl and they were about the same displacement .

 

[Mark71gtx]

It is not uncommon for the plating to be worn on a concrete saw. I would throw a top end on it and put it back to work. Happens all the time around here with good results. If they would learn to keep the filter clean, they would last much longer...

 

[94BULLITT]

The air filter was really dirty on this saw.




After tapping it out


Swept up in a pile

 

[Mark71gtx]

That is how they all look when they come to me. I take it, rebuild it, they pay me, I tell them how to avoid doing it so often, they say okay, and the cycle repeats itself...

 

[94BULLITT]

This guy had 2 TS420s. I got the one going for him a while back and he did not want to mess with fixing this one. I ordered him 5 air filters for it. He also has a TS800. I hope he keeps the filter clean on it.

 

[Al Smith]

Concrete saws take a beating .

 

[Stihlkillstrees]

When my uncle worked for the railroad as a mechanic they blew up 3120k's constantly. The one day he watched them smoke 5 of them in a row.

 

[94BULLITT]

Concrete saws gotta be tough. I wonder what the average life of one is, 6 months, 12 months??????

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[Al Smith]

One of the two Makitas I got from Guido evidently was used to cut metal as well as concrete .That one I don't have running and suspect perhaps it's "powdered " up inside .Which could be clean up or at worse a rebuild .No matter I got the pair so reasonably I can afford the later . It's on the to do list which seems to be getting longer .

 

[Stihlkillstrees]

Concrete saws gotta be tough. I wonder what the average life of one is, 6 months, 12 months??????

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Cutting rail to to make repairs they measured it by cuts. If they lasted 10 cuts it was worth it.

 

[Al Smith]

I don't know about this rail deal .At one time I could torch cut rail close enough for a tie plate .With a cad weld I'm not sure how close it has to be .That's been a long long time ago,in a steel mill .Probably not an approved method on the main line .

 

[94BULLITT]

That is how they all look when they come to me. I take it, rebuild it, they pay me, I tell them how to avoid doing it so often, they say okay, and the cycle repeats itself...

What top end to you use?

 

[Mark71gtx]

I always let the customer choose. They almost always choose the Farmertec top ends. I have yet to see one fail other than from the same abuse that killed the OEM top end. They have never complained about the performance either.

 

[94BULLITT]

Thanks, I was thinking about putting a cheaper topend on it and keeping it.

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[T.Roller]

Typical looking filter. They are not supposed to be cleaned or removed until replacing it