Need help with O&R 20A

[CNew 404]

Ok, I’m stumped... I’m trying to remove a 20A engine from an old chainsaw and I feel like I’ve removed everything that keeps the engine situated in the frame/tank case. I can’t get the engine to budge at all. It looks like it should just slide out but it doesn’t so much as wiggle even with some gentle persuasion taps on the shaft from the opposite side. What am I missing?

Edited January 4, 2020 by CNew
Typo

[Wallfish 698]

I've never taken one apart so can only offer guesses and suggestions.

I know there is a compression release but don't know how it's connected to the engine. You can see the tube or bar at the bottom of your last pic.

[CNew 404]

There is an oil seal on the shaft you pointed out. I haven’t removed it yet, didn’t want to damage it.  Looks like I’ll probably need to pry that seal out and see if there is some sort of bushing or something that is holding the engine in.

 

The pressure release thingy looks like it has room to clear the hole and housing without removing it first. There really isn’t any way to access it anyway without the engine being completely out.

 

Definitely puzzling...

[CNew 404]

Ok, figured it out. I was able to pull the oil seal (probably can’t reuse it now) and sure enough there was a clip holding the shaft next to the bearing. Also, Wallfish you were right, the pressure release valve does have to come off first. There’s just barely not enough room leaving it in. I finally got a 7/16 deep socket that fit the narrow hole in the housing. Piece of cake after that and removing the clip...

[JUST O&R 237]

I see you got it apart I have never taken one apart so you can tell me how. whem  I ready to do the one I have

Edited January 4, 2020 by JUST O&R

[CNew 404]

Absolutely, I learned a lot taking this one apart. Now I know sort of what to expect when I finally tackle my Ohlsson Rice Clinton K150 outboard.

[JUST O&R 237]

In the picture with the oil pump were the lines go in the tank is that a rubber grommet?

Edited January 5, 2020 by JUST O&R

[CNew 404]

Yes, it looks like both tubes have a rubber grommet as they enter the tank. I’m guessing they might be a similar style to the donut grommet for governor vane on the 13A and B engines but I would need to check a parts list to confirm.

[factory 487]

On 1/4/2020 at 6:56 PM, CNew said:

Ok, I’m stumped... I’m trying to remove a 20A engine from an old chainsaw and I feel like I’ve removed everything that keeps the engine situated in the frame/tank case. I can’t get the engine to budge at all. It looks like it should just slide out but it doesn’t so much as wiggle even with some gentle persuasion taps on the shaft from the opposite side. What am I missing?

 

You must have missed the service information for both the 20A engine and Challenger chainsaw I scanned & posted here  ;

 

Section 2 has the "Model 20A Maintenance Manual" and Section 3 has the "Orline Challenger Chain Saw manual".

 

Hope these help and yes a set of new crankcase seals & gaskets are required.

 

David

[factory 487]

On 1/4/2020 at 6:56 PM, CNew said:

but it doesn’t so much as wiggle even with some gentle persuasion taps on the shaft from the opposite side.

 

 

David

[factory 487]

I'm sure I've posted this service bulletin somewhere here before;

 

 

Don't say you weren't warned.

 

David

[CNew 404]

Thanks David!  Of course I remembered those posts after spending the afternoon messing with the engine. Next time I’ll know better and think to check here first!  That was just a dumb mistake on my part...

[factory 487]

Hopefully no damage done.

 

On 1/5/2020 at 2:22 PM, CNew said:

Yes, it looks like both tubes have a rubber grommet as they enter the tank. I’m guessing they might be a similar style to the donut grommet for governor vane on the 13A and B engines but I would need to check a parts list to confirm.

 

The manual does have a parts diagram, but doesn't give the part numbers, I will look to see if I have a separate parts list.

They did use a grommet for both the oil & fuel pickup, I hope it's a standard part they bought in, rather than a custom size.

 

David

[factory 487]

There is a "G&R engines" reed valve (400041) for the model 20A engine here, has make offer too;

https://www.ebay.com/itm/174180575687

The same seller also has a starter spring for the 13B/20A engines (200576) & a pack of screws (100027).

 

David

 

[CNew 404]

Thanks David, I saw a couple of those listings but not the spring.

[CNew 404]

On 2/15/2020 at 7:48 AM, factory said:

https://www.ebay.com/itm/174180575687

The same seller also has a starter spring for the 13B/20A engines (200576)

 

David,

   I’ve never seen the 200576 part number for a starter spring. I’ve seen 200005 for the 13B/20A. The inner coil of the spring looks different between the two part numbers. Was the 2000576 a special spring or a later part improvement?

[JUST O&R 237]

8 hours ago, CNew said:

   I’ve never seen the 200576 part number for a starter spring. I’ve seen 200005 for the 13B/20A. The inner coil of the spring looks different between the two part numbers. Was the 2000576 a special spring or a later part improvement?

I have 13 of the  200576 springs let me know if you need one.

[CNew 404]

Thanks JustO&R! I don’t need one at the moment, but it’s good to have confirmation on the part number.

[factory 487]

17 hours ago, CNew said:

I’ve never seen the 200576 part number for a starter spring. I’ve seen 200005 for the 13B/20A. The inner coil of the spring looks different between the two part numbers. Was the 200576 a special spring or a later part improvement?

 

You might not have seen it yet, but they changed most parts of this type of starter assembly in July 1973, I mentioned the redesign very briefly in the 13B recoil spring thread last year;

https://myoldmachine.com/topic/4816-ohlsson-rice-recoil-spring-for-13b-engine-starter-rebuild-guide-post-9/

Note some parts are not interchangeable such as the starter reel & the housing for that reel.

 

They could have kept inventory of both starter spring, but in business costs are reduced by removing similar/duplicated parts from the warehouse.

 

David

[CNew 404]

Found another photo of the 20A outboard. This one is a Montgomery Ward Sea King 1.5. Interesting thing is the one I have has references to both the Ward Sea King and the Clinton K150. 
https://johnpeckauctions.hibid.com/lot/100898669/montgomery-ward-1-5-hp-sea-king-outboard-boat/

https://www.gotoauction.com/sales/gallery/1332025