hitachi planer noises

I have searched the archives and cannot seem to find the answer. my hitachi planer is acting up and making loud screeching noises…what is wrong? how do I fix it?


…clean all the dust and put a bit of light oil, start the planer and let it get rpms, then stop and put a bit more drops of oil and start again,
alright, no more noise.

I guess that that tool really do not have those 500 shapes that MD says…

Your bearings are worn out. Don't run the tool again until they're replaced. If you cook the bearings seats the planer is done.

I have mine replaced as soon as I have any sign of wear.

dont forget the air compressor blow out

mebe you got a mongoose

stuck in the comutator!


Bearings.  It's plastic.  Don't melt it.  Buy 'em online or maybe Fiberglass Hawaii in Ventura.  Maybe the "Craft" in SLO.


how exactly do I go about replacing these once I get new ones?

Unless you have experience working on electric tools and have the proper bearing pullers, etc., it's best if you take it to a repair shop. Jim Phillips has posted some pretty detailed DIY instructions on here somewhere if you choose to go that route. Buy the best bearings you can get if you shape any number of boards.

Ive never done them on a Hitachi.  So maybe somebody  will chime in and give you the run down.  Take it apart and use a simple bearing puller like you can get at Oreiley's or Napa to pull the bearings.  You can't miss 'em when you remove the shaft..  One on each sjde of the cutter head.  You can tap the replacement bearings onto the shaft with a short length of pipe the right diameter.  Big enough to slide over the shaft, but small enough to fit the inner sleeve of the bearing.

A trick my mechanic taught me years ago is to use a socket wrench for tapping bearings into place. If you have a set of 1/2" drive sockets you should have one that’s the right size.

Is there a point, a certain number of boards perhaps, where one should change them out even if no obivious problems? or if it ain’t broke don’t fix it?

The stock bearings aren't worth a damn, they would need replacing pretty quickly. Any sound or rough feeling, or if the tool starts to bind up (slows down quickly when trigger released; not to be confused with a brand-new set of bearings which can be a little stiff for a couple of boards).

If you have the Clark-mod version, I believe they have a bearing upgrade in their package. When I was shaping PU, I would get at least 500 boards out of a set of good bearings. It's more about heat than anything else - when I would rough out batches I kept two tools at hand and alternated them to let one have 15-20 miniutes ''off'' to cool down. If you get the bearings really hot the lubricant will boil out of them. Don't ask me how I know this, lol.

been looking to order bearings online through fiberglass hawaii… looks as if there are many bearings in the planer, how do I tell which ones are screwed up and which ones are okay? what does a bad one look like? as you can tell, I have never done this before. wanna do it myself cause it was a 90 dollar refurbished unmodified hitachi and i don’t build lots of boards


…clean all the dust and put a bit of light oil, start the planer and let it get rpms, then stop and put a bit more drops of oil and start again, alright, no more noise.

I guess that that tool really do not have those 500 shapes that MD says…

I have a really good repair guy handy so I don't do anything past changing brushes and triggers on my tools. You should be able to tell a bad bearing by turning it, or looking for lube all blown out the sides. Since its a stock Hitachi, its likely that it had the stock crappy bearings. I use Milwaukee bearings now.

The ones that go first are on the blade drum, I think there's one or two more on the motor but don't quote me lol. I'm not an expert on tool repair but I am good at breaking them. Which is why I have 3 of the modified ones (and a Skil 100 museum piece I never use).

the easy way to cut your losses is, take off the belt, fire it up, does it still have the same noises ? Motor only, or no noise, cutter bearings. The bearing that goes most often is the brush side of the motor from the commutator heat

so I found the problem… it is the back bearing on the right side( behind the exhaust)

I lubed it up and the problem was solved for 2 min, then it started acting up again…mainly when I tilt the tool side to side it seems like. looks like there are some sparks back in there too. they are coming off of 2 prong like structures that rest on the spinning axel type thing in the motor. is this normal to have sparks here. what is this bearing called so I know what to order. thanks

Your brushes are sparking on the armature. When brushes get worn they sometimes lose solid contact and there’s a gap which makes the things ‘arc’, creating a spark. With some tools you can stretch the springs that the brushes are mounted on out a bit. This will improve the contact.

But, since you will take the thing apart anyway when installing new bearings you might as well put in new brushes. You will find two plastic inserts on the sides of the planer that look like screw heads. That’s where you get at the brushes.

okay thanks.

can I just try to find bearings at the hardware store that’ll fit the diameter, or do I need to order them specifically for the tool


Sure. Bring the old ones to make sure they match.