Miata: Stuck timing belt gear

So I hit a big snag in my timing belt/waterpump job tonight. I can't get the timing belt gear off the crankshaft so I can replace the seal behind it. Here's a picture so you know what I'm talking about:

It's a '94 so a long nose crank.

There isn't enough room between it and the oil pump for a regular puller and I already broke part of the edge off trying to pry it loose. Since I'll be buying a new one regardless that means the gear itself is expendable at this point. I just need it get it off.

Any idea's?

Jason

PB blaster and two long screwdrivers or prybars on either side.

If its expendable you could try working at it with a dremel until you can split it apart.

If you have a harmonic balancer puller that is small enough you could try tapping two bolts into the gear and forcing it off.

Heat cycles/Cold cycles

Lots of penetrating juice

Drill and tap two holes in the gear and use something like a steering wheel puller.

gjz30075 wrote: Drill and tap two holes in the gear and use something like a steering wheel puller.

Looks like Mazda did the holes already. Some kind of slide hammer hooked to those would be m suggestion.

Is the key part of the gear or is it a separate key and the keyway is machined into the gear?

The cam gear on my Ford 300 was stuck so tight a puller wouldn't budge it, it was a fibre gear and the puller was just breaking chunks off.

I drilled right a few holes from the key slot to the outer edge of the steel insert in the fibre gear and then cracked the insert with a cold chisel and pulled it off.

It worked for me, don't know about your situation though.

Shawn

I'd try lots and lots of heat, followed by a dousing in (nonchlorinated) brake cleaner to cool it off rapidly. Repeat that for a while, and try to pull it off with a slide hammer.

The two prybar method didn't work. Ended up chipping part of the edge of the gear off.

The two holes in it are so tiny I didn't think they were threaded but it appears they might be. I'd have to use an awful small slide hammer though. There isn't a whole lot of from between it and the A/C condendor (I've removed the radiator already)

What kind of heat are we talking about? I assume something better than a regular propane torch correct?

Are the holes thru? What's behind it? Maybe thread a couple of long bolts all the way through to press it off.

Just for giggles, see if a 6mm bolt will thread into those holes. From there, its a steering wheel puller job. As to heat, you want something concentrated and fast, like oxy-acetylene. The only thing thats gonna melt quickly is the seal, so... Persistence is the answer here. If its stuck you may wind up using a dremel to open it up.

Very common for the gear to stick to crank. HEAT oxy-acetylene the gear not the crank. get as cherry hot as you can they pry on both sides with screwdrivers or pry bars.then PM me and i'll sell you a new gear cheap

Used to remove ring gears from fly wheels by drilling a hole thru the face of the gear at the root of a tooth. Stick a cold chisel tween the teeth and smack with a BFH (big berkeleying hammer) and it should split. Works with ring gears, Ive never tried on a crank sprockett.

This is a similar to a persistant problem on the crank gea r on a Neon. Most guys use the chisel/ BFH/ crack in half method,

Ok, no luck with a puller. The threaded holes in the gear are really tiny (M4 bolts) so I couldn't keep the puller straight enough as I turned it before the bolts started to bend. Plus its hard to keep the crank from turning. I put the tranny in 5th but that didn't seem to help much.

I started cutting through it with my cheap HF rotary (Dremel like) tool. I made it about half way through before it overheated and died. I'm picking up another one today on my way home from work so hopfully i'll have it off this evening.

Ouch, that looks on there pretty good. I hate when stuff like that ruins a perfectly simple project. Smear some anti seize on the new one :-)