MM if it troubles you that much just change the boss and blade carrier to a Rover type, but I can tell you if you are having trouble fitting the blade carrier on you do not have a hope in hell of getting the blade boss off a Briggs. I find it often takes up to 6 tons to get them off
23 mm isn't accurate enough , Norm mentioned a Tecumseh 7/8 boss would fit without the ears ,I'm sure there were images MM.
Yes I agree if I had 3 hands ,one to hold the crank from turning ,one to hold the blade plate into position and one hand to tighten the bolt then my rattle gun shouldn't be needed for routine maintenance.
I was like Norm and struggled to get the boss off without a lot of force but found a 3 leg puller even when it's not pulling perfectly straight will always remove the boss easier than 2 legs ( or 2 bolts )
I've removed at least 100 crank hubs with the 3 leg puller in the below images and lots hadn't been off in 50 years ,just using a 12 inch shifter to tighten the puller attached to the bearing plate and that doesn't pull perfectly straight because one leg pulls on the bearing remover bolt.
Haven't had a blade hub not come off , once the puller is on ,you tighten the puller bolt as much as you can with the 12 inch shifter and this alone won't budge the hub ,you need to put one side of the hub on a block of steel (train track ,I beam ,hammer head ,etc) and then use a brass drift on the hub and hit the drift with a big hammer then the hub will move and you tighten the puller again and use the hammer again until the hub just moves by tightening the puller bolt.
On old B&S motors that I was throwing out I would cut the crank shaft off with the boss and then use a press to remove the boss but I find it easier now to smash one side of the alloy off the bottom of the motor so I can get the brass drift on an angle to the boss and hit the boss off , you do get a small flat side on 3 positions on the boss by hitting it this way but no matter how rusted the boss is, it still comes off.
Disadvantages of removing the boss my way is if you hit the boss too hard some will crack on one side but this does make them much easier to remove but makes the boss useless , it's ok when it cracks if you're replacing the boss anyway.
Another disadvantage and I didn't think this was possible is I've completely stripped out the thread on my puller just using a 12 inch shifter but I expect the cheap puller is the problem as I found it thrown out at a scrap metal yard even though it looked brand new when I found it .If you spend more and buy something well made it usually lasts a lifetime .
I'm OK with pulling things apart, only times I've had problems is when some ditz has used red Loctite or similar, but a bit of heat fixes that.
Last time that happened I nearly flipped an old Toyota Corolla onto its roof trying to undo a front wheel hub nut with a length of steam pipe and a three foot breaker bar with a 1 inch drive socket.
As said the carrier is firmly mounted now and the rest of the mower will probably fail before the boss/carrier connection does.
If necessary there's the remains of a Toro in a shed which has a tapered end on the drive shaft which fits into a boss with sensibly designed bar locating tangs, might have a go at tapering the end of this Corvette shaft if I can't find an easy replacement for this two eared thing.
Hi Max, I have no idea how you can get some of them off with just a 3 jaw puller, a couple I have not been able to move even with the 6 ton jack pulling on them. One I distinctly remember id the GXV 160 I ended up putting on the split bodied Tornado, mate wanted it put on an Ariens but I couldn't move the boss so I suggested to him that I build the wide body one, which he loves
MM if you don't like the 2 ears on the boss just get a cutting disc and cut them off but cut both sides even, so the hub is still balanced and put a wet rag around the crank where the oil seal is so you don't melt the seal with sparks and excessive heat.
I've cut them off before but removed the boss to do so but you could cut the boss on the mower if you're careful.
You'd still want to tighten the crank nut up tight so the friction connection doesn't slip.
Norm ,if a hub is rusted on solid it just takes more force to try and move it free and this is how you can damage parts but if you apply a fair amount of force to the boss and then shock the rusted connection loose it will come loose 99 percent of the time.
The same sort of principle is used at mower shops to remove rusted on ride on mower back wheels but they use an air hammer to hit the centre of the axle.
If you have an old briggs that you are throwing out that the boss won't come off ,I don't even need to use a puller ,if I hit the boss in 3 spots it will always come off, because of the shocking of the rusted connection it takes less force to remove.
I bought an Ingersoll rand rattle gun over 20 years ago , it was only around $50 new ,never had a problem with it. I've also sold a fair few 2 Hp good air compressors for $15. each and thrown out at least 10 that could have easily been repaired, just because I had too many.
The Victa Corvette 700 became my favourite mower, easy to start, did a good cut, lots of power without needing maximum revs, very quiet, filled the catcher nicely, was able to idle slowly when removing and emptying catcher, great fuel economy, very comfortable to push and manoeuver.
Hit a rock and motor stopped instantly. No grinding type of noise, just stopped, big gouge into the rock. Wouldn't start again, compression OK, spark OK. Crankshaft not bent. Put some fuel down the spark plug hole, couldn't get a cough. Rope frayed with all the pulling, then broke so took off the covers and used a drill and socket to spin the motor but nada, nothing.
Appears the nut on the flywheel has never been touched, rather rusty. Could not budge the nut (don't have an impact driver) but plenty of big hammers, so couldn't take off the flywheel.
Suspect the flywheel key is sheared or flywheel slot damaged. Yes/no ?
Fortunately I still have 24 others, the grass has started to go beserk lately.
I agree they are a nice motor - due to massive time constraints I have been working under since august, I have only been using a masport SP with that same motor on it- except the IC cast iron sleeve. Havent even touched a 2 stroke or anything since then. Fires first or 2nd go, good on fuel and plenty of power so no complaints
Pull start is weak as though - looks like they made it a large puller presumably to make it easier to pull over - downside is there is more flex in the starter and more force on the parts if you give it a really decent pull
Thanks for your reply Tyler. The mower is sitting in the "morgue" along with a few others needing an autopsy before being either scrapped or put in the queue for repairs. Have been putting some oil on the stuck nut every now and then and have found what looks to be an identical flywheel nut from an old B&S defunct motor in case I have to resort to the angle grinder and cold chisel trick.
I find it interesting to ponder just why the DOV motor was so pleasant to use. Modifications and developments in OHV operation methodology have always been made with the aim of reducing/eliminating valve flutter or bounce at high rpm - think Ducati and their small desmodromic singles of the 1950s and 60s which developed a lot of HP from very few CCs, albeit fast but fragile.
Yet the Victa DOV just plods along slowly revwise with a very wide smooth powerband.
Anyway hopefully I'll be able to get that motor running again. Meanwhile I was given a Gardenline mower last week with a B&S Sprint 375 motor. Usually I wouldn't bother giving anything Gardenline a second look but this one has a really solid rustfree deck, only needed the air filter foam replaced and an oil change and it is flying, may even get an extra pair of blades added to the two blade carrier.
After putting a couple of drops of thin sewing machine oil on every few days for several weeks the flywheel nut unscrewed to reveal a sheared key. Hooray ! The keyway in the shaft is unharmed but the alloy flywheel keyway has been gouged wider a bit. I had some 4 mm keystock in the shed but the original key looks a tad bigger. Interestingly the original has a stamped B & S logo.
Being Saturday arvo and I'm out in the bush can't just wander down to a mower shop for a new B & S key so thinking might just use a bit of what's inhouse and some threadlock, but wondering if there's anything else I should be looking for when a motor hits something hard enough to shear a key. As mentioned everything else seems OK.
Put the new smaller key in, smeared some threadlock around, put the flywheel on and as the nut was being tightened noticed two cracks radiating out from the centre of the flywheel.
The flywheel (marked 53D) from an old Toro has exactly the same OD and I was happily getting ready to bodge up a starter arrangement but noted a big chunk flaked off one side of the slot in the crankshaft taper therefore will be scrapping this motor.
