SC252 Pillow Bearing Temperature

[Mark Schenkel]

Recently replaced the jackshaft pillow bearings on my SC252. On a 65 degree day they still get pretty hot. Not boiling hot (i.e. spit on them and you see sizzle), but would be difficult to keep my finger on it for extended period of 5-10 seconds. I find the jackshaft bearings get much hotter than the cutter bearings. Is this normal?

I have a large Vermeer 665A and these bearings don't get nearly as hot. Although the RPM are much lower.

 

[lone wolf]

Recently replaced the jackshaft pillow bearings on my SC252. On a 65 degree day they still get pretty hot. Not boiling hot (i.e. spit on them and you see sizzle), but would be difficult to keep my finger on it for extended period of 5-10 seconds. I find the jackshaft bearings get much hotter than the cutter bearings. Is this normal?

I have a large Vermeer 665A and these bearings don't get nearly as hot. Although the RPM are much lower.

And they wear out fast too.

 

[TheAMMIXman]

I don’t think mine get hot enough to sizzle spit but they definitely get very warm to the touch.

 

[lone wolf]

Recently replaced the jackshaft pillow bearings on my SC252. On a 65 degree day they still get pretty hot. Not boiling hot (i.e. spit on them and you see sizzle), but would be difficult to keep my finger on it for extended period of 5-10 seconds. I find the jackshaft bearings get much hotter than the cutter bearings. Is this normal?

I have a large Vermeer 665A and these bearings don't get nearly as hot. Although the RPM are much lower.

Mine did that too no matter what I did i tried aligning all the pulleys, I am sure those bearings are too small for that horsepower. I had more trouble with the bearings at the cutter wheel they used to break way too many times over the years. Keep all in alignment perfectly and dont over tension belts.

 

[iowagold]

what are you using for lube?
and is the hot during a long grind?
look in to good high temp lube.

and maybe an auto luber to help on getting good fresh lube in there...

what brand of bearings did you use ??
Timken?

 

[Mark Schenkel]

what are you using for lube?
and is the hot during a long grind?
look in to good high temp lube.

and maybe an auto luber to help on getting good fresh lube in there...

what brand of bearings did you use ??
Timken?

Sometimes I use a better quality marine/water proof grease. I am pretty good about keeping them greased.
It may be I have the belts too tight.

 

[cookies]

You really get what you pay for in a grease, just because its marine grease does not mean it is rated for bearings or worth a darn. After dealing with several folks trailers always having bearing failures I made them ALL switch to lucas red n tacky because its rated for wheel bearings, steering and suspension and needle bearings etc and very easy for them to pick out at the store without any mistakes and the bearing failures stopped. There are other versions of grease that work just as well but I find people will grab the cheapest version/brand every time to save 2-3 bucks per tube. Any bearing that is not very high quality you must wash them out and repack them even if they are sealed as I have found manufacturers are putting very low quality non moly grease in them or even clear petroleum jelly.

 

[lone wolf]

https://www.machinerylubrication.com/Read/28664/dangers-of-overgreasing-I think over greasing will make it overheat. I noticed that the bearings lasted longer when I stopped greasing them all the time.

 

[iowagold]

yes the lucas red rocks!
we also use the red in the oreilly brand.
both work well for us.
hit the zerks every 4 hours or so on high speed high load bearings..
or get an autolube unit and set to 15 min on low volume.

 

[NCgrinder]

Back in my racing days ,I kept track of tire temps with an infrared themometer. I use the same gun on my grinder bearings to track bearing operating temps. Most bearing mfrs will supply max operating temps. So what I do is measure before starting (to determine ambient temp )and after running awhile I measure again. Belt tension /misalignment both contribute greatly to failure. Too much belt tension is as bad as too little tension. Too much causes bearing heat and belt stretch , too little causes belt slippage & wear ,pulley wear,etc. I can also detect when a bearing is failing due to wear/fatigue.
These thermometers are relatively cheap ( $20-$60) and can save you money in the long run...
Of course ,spittin' on a hot bearing and watching it sizzle has it's merits...!!!
Stan