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OSU 09
09-09-2010, 05:23 PM
I bought a giant vac leaf loader this past spring that needed some work done. I was well aware that it was in need of some TLC and that the impellar needed replaced. But I got the loader, 2 backpack blowers and a push blower for $200 bucks so I wasn't complaining about it needing some work. Well after putting it off all summer, leaf season is almost here and I need to get this up and running. I want to take the impellar off and take it to a fab shop so they can make me a new one, but I can not get the darn thing off. Can anybody help me out? Its a model 1901-C. I will get some pics up when I get a chance.

dutch1
09-09-2010, 08:38 PM
I haven't worked on a Giant Vac in a while so you can take this with what it's worth. Remove the bolt that retains the impeller to the crankshaft then check for threads in the outer part of the impeller. If threads are present, obtain a bolt of that size and thread it into the impeller and against the crankshaft. This should push the impeller off the crankshaft. Apply plenty of penetrating oil. In addition, some heat may be necessary but precautions should be taken to heating the crankshaft to the point of damaging the crankshaft seal. If no threads are present, you may be able to substitute a bolt the same thread size as the retaining bolt, some what longer. Thread it as deeply as possible into the crankshaft then use an impact hammer on that bolt while at the same time applying pressure to the back side of the impeller. Otherwise a puller of some kind will be needed.

If you are having a fab shop build an impeller, make sure they are able to balance it for the roughly 3600 rpms it will turn. I have seen impellers that have been repaired and welded on that were not balanced properly which resulted in premature damage to the crankshaft bearing surface, not to mention shaking the crap out of the equipment.

Restrorob
09-09-2010, 09:23 PM
Remove the bolt that retains the impeller to the crankshaft then check for threads in the outer part of the impeller. If threads are present, obtain a bolt of that size and thread it into the impeller and against the crankshaft.


Dutch is right, I just want to add that you get a fully threaded bolt 4 or more inches long for jacking. Once the end of the bolt hits the end of the crankshaft the end mushrooms, Then you can't back it out of the impeller without damaging the impeller threads or breaking it off in the impeller.

With the longer bolt you can screw it through the impeller enough to cut the mushroom off the end and screw it back out.

Don't ask how I know this..... :dizzy:

CT18fireman
09-09-2010, 09:25 PM
Giant Vac has tons of impellers available and they aren't much money. They have two styles. One has a threaded nut welded to the end that will take a bolt and use it to "pull" the whole impeller off the shaft. Sometimes it works if it hasn't been sitting rusting for years.

The other style is an impeller with a hub that is seperate and bolts to the impeller. These hubs can be tapered or straight depending on engine model. The hub will be bolted to the impeller with three smaller bolts and to the crank with the large center bolt. Remove both. There should be some threaded holes in the hub. Use these and some bolts to pull the hub out.

Either way when you reassemble use some grease, I like the silver lithium stuff on everything, shaft, keyway, impeller hub etc. Then use a bit of blue loctite on the bolts.

OSU 09
09-10-2010, 08:39 AM
Giant Vac has tons of impellers available and they aren't much money. They have two styles. One has a threaded nut welded to the end that will take a bolt and use it to "pull" the whole impeller off the shaft. Sometimes it works if it hasn't been sitting rusting for years.

The other style is an impeller with a hub that is seperate and bolts to the impeller. These hubs can be tapered or straight depending on engine model. The hub will be bolted to the impeller with three smaller bolts and to the crank with the large center bolt. Remove both. There should be some threaded holes in the hub. Use these and some bolts to pull the hub out.

Either way when you reassemble use some grease, I like the silver lithium stuff on everything, shaft, keyway, impeller hub etc. Then use a bit of blue loctite on the bolts.

Really? Where can I find these impellars? I got a quote from the dealer and it was $600. Thats a bit much for something I only paid $200 for.

CT18fireman
09-10-2010, 08:55 AM
$200 is a great price for a used unit. Now spend the money to make ot productive and SAFE.

$600 is not much for an engineered piece. It's not just a chunk of steel welded together. It is designed, welded and balanced to be used as a vac impeller. Most local shops would probably not even risk making one. If you do find someone to make and correctly balance an impeller it will cost more then ordering one.

That's a lot of heavy steel spinning at 3500 rpm.

pugs
09-10-2010, 12:00 PM
Really? Where can I find these impellars? I got a quote from the dealer and it was $600. Thats a bit much for something I only paid $200 for.

Feel free to go cheap....I am glad I am 2 states away from the machine. Hopefully the shrapnel wont make it this far.

OSU 09
09-10-2010, 05:39 PM
I really hate how most people on this board jump all over people every chance they get. Everyone seems to be looking for an "I am mighter than you" fix. Anytime someone asks a question or has a comment it seems to be everyones response that the person is an idiot, doesn't know what they are doing and should just get out of the industry.

Nobody even bothers to think or ask what kind of professionals might I be getting a quote from to make the part. The one shop makes mulch mules, so I think they know a thing or 2 about high RPM applications. The other is a shop in my town that makes large leaf and debris vac systems for municipalities all accross the country, again I think they might have the know- how and skills to produce a high quality part.

But I guess since I asked the questions and I have less than 200 posts on this site, that must make me an idiot right?

OSU 09
09-10-2010, 06:42 PM
Btw, I am not trying to sound like a jerk or incredibly defensive. I have actually never had a problem on this site with people. I just know from reading peoples comments when someone asks a question that there is a lot of dissrespectfullness. I agree that there are many times people asking questions that if they are in the industry they should know the answers to. And there are many people doing this job that honestly just shouldn't be. But there is nothing we can do about that on an internet forum. So just try to show people some respect.