# Crankshaft pulley stuck - Toro 724/H70 engine



## AnimalHungry (Jan 29, 2013)

I'm stripping down my Toro 724/Tecumseh H70 engine but I can't get the pulley off the crankshaft. The flywheel came off with a little persuasion, but this pulley on the other end is stuck hard. I've removed the two hex head screws from the pulley and soaked it in penetrating fluid but it just won't budge. Any ideas how I get this thing off?
Cheers
Simon


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## CarlB (Jan 2, 2011)

I would get a propane torch and heat it up good. If you cant get it to come off after you heat it you may want to try and tap it in a little just to break the rust free. If you have a puller you can use that but don't pull too hard or you may brake the pulley


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## woodtick007 (Apr 9, 2011)

AnimalHungry said:


> I'm stripping down my Toro 724/Tecumseh H70 engine but I can't get the pulley off the crankshaft. The flywheel came off with a little persuasion, but this pulley on the other end is stuck hard. I've removed the two hex head screws from the pulley and soaked it in penetrating fluid but it just won't budge. Any ideas how I get this thing off?
> Cheers
> Simon


You need to go to your parts store and rent or borrow a puller. Put your impact wrench on it and it will come off. Heat may help but by the time you heat the pulley hot enough you also have the crank and everything surrounding it very very hot. 
How old is your Tecumseh? 51 years old? Why are you tearing it down? Its my understanding that a Tecumseh is a 40-50 year running engine. I hope you didn't get a bad one.


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## AnimalHungry (Jan 29, 2013)

Thanks guys. I'm gonna buy a puller first and try knocking it on a bit more first, smoothing the exposed bit of the shaft off and then squeezing it off with some heat and the puller. Pretty sure that will work.

I was pounding it through a giant snow bank in my yard when the engine sputters and dies with a poof of dark smoke out of the exhaust. Then I noticed that there was a load of engine oil coming out of the valve cover. I tried to start it and all it would do is give me the dark exhaust smoke. It still has a spark, fuel is getting in there and the plug isn't oiled up, so I'm hoping that the piston and rings are in decent shape. 

So I suspect it's a valve issue, or even could be a slappy piston and tired rings, so I'm stripping it down to take a look. When I have it in pieces I'll lap the valves to get them seating nice, and depending how the cylinder and piston looks I may give it a rebore and new top end. I wouldn't have thought a rebore on these little engines would cost much. Anyhow, that's the plan for now. 

Thanks again for the pointers on the pulley removal!

Cheers
Simon


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## gsnod (Sep 2, 2013)

OK -- a similar issue with getting the Pulley off of my blown Tecumseh engine. The pulley does have two hex/allen keys through it that I can't break free. One assumes that once I get those out, I'll be able to pull the pulley off. Any suggestions on how to break the allen nuts free?

I've been using an allen wrench, but am actually twisting them....I simply can't get enough leverage on them. I wonder if they make a 3/8 inch allen head piece that I could put on a ratchet?


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## Kiss4aFrog (Nov 3, 2013)

Like this???
.


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## 43128 (Feb 14, 2014)

when i replaced the engine on my blower, i soaked the pulley in pb blaster overnight, and me and my friend Mr. Crowbar were able to get off in about 5 minutes by placing him behind the pulley and prying without damaging the crankcase, the pulley will be on their tightly but it will come off eventually


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## pcfithian (Mar 3, 2014)

Time for a Predator repower. See http://www.snowblowerforum.com/forum/toro-snowblowers/18921-predator-engine-toro-724-a.html


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## greatwhitebuffalo (Feb 11, 2014)

careful with those set screws. don't strip them or you'll be in a world of hurt. heat the pulley area where the set screw goes in with a torch, then turn them out while they are still hot. propane torch might work but preferably an oxy-acetylene torch and get them good and hot first before trying to turn them out. make sure the allen is fully seated in the set screw before turning it, and don't burn your hands on the hot pulley after heating it- good luck.


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## gsnod (Sep 2, 2013)

OK -- greatwhitebuffalo gets the win here. I took my friendly torch and heated up the pulley and the set screws started to turn...applied a bit more heat, and I could get them out. Then took my puller and worked to pull all the way off the shaft. Lesson learned.....put some grease on the shaft from now on, as it was very dry. But of course, this thing had been on there since 1988. 

Now all I need to do is either look for a replacement Tecumseh Engine, or put on a predator. The challenge with the predator is that the drive belt tensioner mounted right to the engine with two bolts....I doubt the predator has those bolt holes. That alone will probably force me to a Tecumseh HM80 replacement.


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## pcfithian (Mar 3, 2014)

The bolt holes on the Predator are an exact match for the belt tensioner bracket.

HF has a coupon sale for $99 on these engines now


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## RedOctobyr (Mar 2, 2014)

I also just had to drag a pulley hub off my machine (off the impeller shaft). Stripped out one of the setscrews, I had to drill that out, then use a gear-puller to drag the hub off, after heating it. 

I'm leaning towards coating everything with anti-seize, rather than grease, before re-assembly. 

I'm glad you got yours off! Good luck with the engine.


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## gsnod (Sep 2, 2013)

Thanks pcfithian and RedOctobyr -- yep, anti-seize is probably better for the shaft. 

Hmm....yea, I see a HM70 on Craigslist for $75, and I've put a new Predator on a different Toro already this season. It is nice how they line up exactly! 

I'll need to buy a sheave to go from a 3/4 shaft to my 1 inch shaft so I can use the same pulley. That's why I wanted to get the pulley off, so I can continue to use it on this toro. So, for $15 more, and $20 for a sheave, I'll be able to get this 1988 Toro back running.


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## AverageJoe (Feb 19, 2014)

RedOctobyr said:


> I'm leaning towards coating everything with anti-seize, rather than grease, before re-assembly.


I was thinking about doing this with the axles, etc......any draws backs in doing this? I know it's made for auto spark plugs going into aluminum heads
but still it provides lubrication. Not sure how long it would last on moving surfaces though?


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## RedOctobyr (Mar 2, 2014)

I wouldn't use it on an area where 2 metal things are actually moving/sliding on each other. 

As I understand it, it's only meant to keep things from rusting & locking together over time. Anti-seize is not meant as a lubricant for things that are actually moving when in-use. It's not a grease/oil. 

I wouldn't put where a shaft rides (rotates) against a bushing, for instance. Like between the auger shaft, and the bushings it rides on. There you have constant motion between the two. I'd use grease there, instead. 

But I'd be OK with using it between a shaft and the inner race of a bearing. In that scenario, they should be assembled, then the bearing race *should* remain stationary against the shaft. Any motion should only be within the bearing itself. 

So, to refine my earlier statement: I'm planning to anti-seize the outside of the shaft, and the inside of the hub that slides onto it, since they locked together. As well as putting it on the setscrews in the hub, and where the pulley bolts onto the hub (the pulley was also difficult to remove from the hub). 

I might put a little where the bearing sits on the shaft, but I'm not really worried about that area rusting up tight over time. I could also use grease there.


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## Kiss4aFrog (Nov 3, 2013)

+1 with RedOctobyr, it's labeled a lubricant but the stuff I've taken apart after a couple of years the anti-seize compound is usually dried out. I don't think you'd want to use it in place of grease with moving parts.


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## AverageJoe (Feb 19, 2014)

Thanks guys....always best to ask before doing!


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## HCBPH (Mar 8, 2011)

*Premounting treatment*

I used to use grease on the shafts before mounting pulleys. I've since started using antiseize compound, lubricates plus it helps prevent pieces from seizing together. Don't really know if it's so much better but it's worked out OK for me.


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