Could this be the problem?

Found this in the gearbox of my snowblower. Now I have to remove rusted in 1/4" roll pins- tried pb blaster, heat, kinetics. I understand that mechanics or machinists may use a hydraulic press?

Best way to remove roll pins is with a roll pin punch.

And, yeah, your gear looks broken.
http://www.brownells.com/gunsmith-t...-tools/punches/roll-pin-punches-prod5551.aspx

Tried that. It looks like removal is a common problem

A little JB Weld will set you right again.

Little stick'em, Little Vicks and you'll be right as rain.

the old rototillers used a brass bullgear also, I've seen many of those bust the teeth off and they were a b*tch to get off of the shaft.....
I'd use a little heat, then if you can, put the part of the shaft with the split ring in it over a socket large enough to punch the pin into it. you'll definately need a pin punch, or maybe you can find some steel rod that's the same diameter. But a pin punch will be better. I'd soak it good with a catalyst spray, then put a little heat to it before driving it out...

the gear is probably designed to be the weak link, now getting it apart to change it is another story. soaking, heat and pin punch as stated above. Mke sure it is a straight sided pin not tapered, which means it will only come out from one side, not likely but possible.

I'm replacing the whole gearbox, at a cost of $300. This was in my snowblower- I sucked up a big flat rock evenly with both augers, which jammed both sleeves against the auger drive shaft so that the shear pins didn't pop. The snowblower is 10 yrs old, but it's an Ariens and has never given me a lick of trouble- I think I'll get another 10 out of it with this fix.

The roll pins hold the impeller to the shaft connected to the gearbox. Not that they would see some harsh conditions clearing my 250' driveway in NH for 10 years, but there may be a tad bit of corrosion. If I can't do it in another couple of sessions with it- I'll bring it to a machinist.

I wish I could- they're pretty close to flush with the hole

I'd drill it out, but it's got a real hard temper and it's at a weird angle. That $83 for a new impeller dont look so bad right now, except for coming after $300 for the gearbox.

If you can get to it with a drill,l a carbide tipped masonry drill may work.
For frozen/rusted parts there is no substitute for the" blue flame wrench".

A little more info...a pic would help immensely.

I assume the pins sit above the surface of the shaft somewhat, at this time?

What heat source have you used so far?

Penetrants? Heating then cooling with a stream of penetrating oil?

Can you cut the pin flush with the shaft then file it flat?

Use the correct roll pin punch with an engineers hammer or a large (48 0nz. minimum) ball peen?

You could buy a solid carbide drill bit.

http://www1.mscdirect.com/eCommerce...l-Bits/Metalworking-Multipurpose-Drill-Bits/S

also what will help is when striking the roll pin with the punch, back up the shaft behind the pin with a large hammer so the blow is solid not bouncing. might take 2 people.

Grind the pin flush with the shaft. Use a taper punch to break it loose, then a pin punch to drive it through. BIG hammer if needed. I've never had one that I couldn't move.

Got the pins out, now working on the impeller

WINNER I'll personally vouch for roll pin punches as being the best way to get 'em out. That combined with a dead-blow ballpeen hammer and I've not had any roll pins I couldn't get out, yet. Big difference from going at it with a standard drift punch, also called a "pin punch" at times. Roll pin punches have balls on the ends.

Air hammers with the right tool in them can work wonders to. Mine hits about 3600 times faster than I can.

A good support jig and something sized appropriately to press the pin out via hydraulics would be a slam dunk last resort solution for me.

I use a taper punch to break them loose, than a pin punch. I have bent too many pin punches breaking seized pins loose.