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Old Jul 17, 2012, 03:24 PM
Vango
Joined Jun 2009
18 Posts
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DLE 20 shaft removal (HELP)

So I was installing a new prop on my DLE 20 and tried removing it because it was too tight of a fit. Used a hammer to tap on the shaft while I held the prop (bad idea) to get it off. Ended up moving the shaft backwards 1 mm and jamming the shaft into the backplate. Motor frozen. So I am trying to remove everything to clean and see what needs to be replaced. I cant figure out how to remove the shaft
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Old Jul 17, 2012, 04:21 PM
Zor
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Ontario,Canada
Joined Feb 2007
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Quote:
Originally Posted by jasono979 View Post
So I was installing a new prop on my DLE 20 and tried removing it because it was too tight of a fit. Used a hammer to tap on the shaft while I held the prop (bad idea) to get it off. Ended up moving the shaft backwards 1 mm and jamming the shaft into the backplate. Motor frozen. So I am trying to remove everything to clean and see what needs to be replaced. I cant figure out how to remove the shaft
I do not know if the following may help you but I am trying to help.

First I am suprised that you were able to push the prop on without pushing the shaft backward if it is so tight.

In similar situation I was able to remove the prop using two screwdrivers opposite each other and prying out.

The shaft quite obviously comes out the rear end of the crankcase. You may not have to take it out. Prying the prop out may bring the shaft back to its position.

The exploded view of this engine shows a ring inside the back cover that limits the rearward motion of the shaft. It makes me think that the shaft runs on sleeve bearings.

That ring may have become indented with knocking backward on the shaft and has now locked the shaft from turning.

Suggest you remove the back cover and have a look.

To remove the shaft the connecting rod has to be removed from the chrankshaft pin. That means moving the connecting rod backward out of the pin. To do that I had to remove the cylinder so that the piston and connecting rod could move backward.

Then the shaft came out easily.

Try first to pull the prop out by prying or better yet use a small wheel puller.

With my luck someone posted while I was typing .

Good luck,

Zor
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Old Jul 17, 2012, 04:49 PM
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Joined Jul 2011
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What Zor said.

If that doesn't work.... A bigger hammer is needed: D

Ken
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Old Jul 17, 2012, 06:02 PM
Vango
Joined Jun 2009
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Ok thanks. So I wont hurt it by hammering out the shaft once the piston is out?
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Old Jul 17, 2012, 09:56 PM
Zor
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Originally Posted by jasono979 View Post
Ok thanks. So I wont hurt it by hammering out the shaft once the piston is out?
jasono979

I am writing not knowing your talents with this stuff.

A drop of penetrating oil at the prop hub and shaft may very well get that prop off with the two scewdrivers before removing the cylinder.

Do not use any hammer "metal on metal" .

Always use a small block of wood "pine, spruce or bass" on the engine part and hammer gently on the wood. In any case not harder than necessary to get that prop out.

A little bit at a time (each blow) as things are moving.
A bit of patience pays off.

If you hold the crankcase in a vise, tighten the vise on the engine mounting flanges with some thin wood in the vise jaws; do not tighten too much.
You would risk of breaking the engine flanges.

Zor
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Old Jul 18, 2012, 08:01 AM
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If all you did was slide the shaft back,remove the rear cover,and with a wood dowel as a drift,tap the shaft forward sharply,and see if it frees up.

I'd be surprised if the engine has sleeve bushings in it....most gassers have ball bearings,and it seems to me you've just knocked it back in the bearings.

I've had wood props slip on the shaft easily,and with high humidity,swell and grip the shaft tightly.

If you ever strike a shaft again,be sure the prop nut is threaded on,to be even with the end of the shaft,to protect the threads.

I have an aluminum "acorn"nut/spinner that I use on stubborn shafts....always protect those threads....
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Last edited by epoxyearl; Jul 18, 2012 at 08:09 AM. Reason: added 'after thought'
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Old Jul 18, 2012, 09:50 AM
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Quote:
Originally Posted by epoxyearl View Post
If all you did was slide the shaft back,remove the rear cover,and with a wood dowel as a drift,tap the shaft forward sharply,and see if it frees up.
This is the first thing I would try.
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Old Jul 18, 2012, 04:01 PM
Vango
Joined Jun 2009
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Thanks guys. I believe you have to heat the casing in order for the shaft to slide out. I am just going to try adding a gasket to the rear casing so that it will spin freely as it is.
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Old Jul 18, 2012, 06:17 PM
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You do need to tap the shaft forward as far as possible.....If the shaft is rearward ..005 or so,it may cause the piston to be cocked in the bore,and cause early wear out..freeing it up with a gasket isn't wise-there's something wrong somewhere...
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Old Jul 18, 2012, 06:43 PM
Vango
Joined Jun 2009
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True. But there is enough play on the connecting rod that it will be in the same position regardless. I have tried tapping it back in but unless I heat it up it wont go any farther.
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Old Jul 19, 2012, 01:32 PM
Zor
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Originally Posted by jasono979 View Post
True. But there is enough play on the connecting rod that it will be in the same position regardless. I have tried tapping it back in but unless I heat it up it wont go any farther.
Jason,

I have to assume that you have the manual in which there is a nice exploded view of the engine.

I also have to assume that the following may be helpful to you.

This engine has two ball bearings on the shaft and also needle bearing for the connecting rod.

Ball bearing installation and removal implies interference fits. That means that the inner race dia slips on the shaft with some interference (the shaft is a tiny bit larger dia than the hole of the inner race of the bearing.

Similarly the bore into which the outer raceway fits is a tiny bit smaller than the outer diameter of the outer raceway of the bearing.

The purpose of these interference fits is so that the inner raceway of the bearing turns with the shaft and the outer raceway stays fixed in the crankcase (does not turn).

It may help to use penetrating oil to assist the interference fit slipping out.

Also careful use of heat may help.

I suspect that you may not have to remove this crankshaft. All you may have to do is assure that the bearings are back in their proper location on the shaft and crankcase.

For whatever this may be helpful.

Zor

P.S.: If you do not have the manual you can download it. Just search DLE+20+manual.
I downloaded the manual.
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Last edited by Zor; Jul 19, 2012 at 04:01 PM. Reason: pupose changed to purpose. Also added that I downloaded the manual.
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Old Jul 19, 2012, 01:57 PM
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IF, big IF, you plan on doing a rebuild on the engine, meaning a new ring and bearings then heat is your friend. There are a couple ways to go about it that will give you even heat without the chance of warping the case. I use the oven at about 300 degrees or I often use a big pot of boiling water. Both ways work very well. Once a case is heated bearings can be easily removed and replaced. Removed when hot by slapping the case on a flat piece of wood or using a wood dowel as a drift punch. I have a number of tools made for bearing removal but these things woke very well. Bearing replacement, a hot case then a socket over the front of the race and a whack with a hammer. {on the socket!!} If a prop gets stuck on the Crank go buy yourself a battery wire puller from the auto parts store, it's just a small two prong gear puller. Then buy yourself a prop reamer, tower sells them in both metric and SAE.
Never take a hammer to your engine like that again!!
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Old Jul 23, 2012, 03:36 PM
Vango
Joined Jun 2009
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Thanks guys! I have learned a ton! I am new to working on gas engines and I have learned my lesson. (the hard way) So can I heat it up to slide the shaft back into the slide? Or will I need to buy new bearings? Thanks
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Old Jul 23, 2012, 03:43 PM
Vango
Joined Jun 2009
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Here are some pics of the bearings. I tried hammering the shaft back to its original position but I think its gonna require some heat...
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Old Jul 23, 2012, 11:52 PM
Vango
Joined Jun 2009
18 Posts
Quote:
Originally Posted by Zor View Post
Jason,

I have to assume that you have the manual in which there is a nice exploded view of the engine.

I also have to assume that the following may be helpful to you.

This engine has two ball bearings on the shaft and also needle bearing for the connecting rod.

Ball bearing installation and removal implies interference fits. That means that the inner race dia slips on the shaft with some interference (the shaft is a tiny bit larger dia than the hole of the inner race of the bearing.

Similarly the bore into which the outer raceway fits is a tiny bit smaller than the outer diameter of the outer raceway of the bearing.

The purpose of these interference fits is so that the inner raceway of the bearing turns with the shaft and the outer raceway stays fixed in the crankcase (does not turn).

It may help to use penetrating oil to assist the interference fit slipping out.

Also careful use of heat may help.

I suspect that you may not have to remove this crankshaft. All you may have to do is assure that the bearings are back in their proper location on the shaft and crankcase.

For whatever this may be helpful.

Zor

P.S.: If you do not have the manual you can download it. Just search DLE+20+manual.
I downloaded the manual.
Thanks for your input. You think I can heat up the bearings to slide the shaft back in place? Or do I need to replace them?
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