Lee 3 #1 Posted February 1, 2016 I am new to this site so I hope I am doing this post in the wright place. I have a Lancaster chain saw with a O & R SLA-20 ENGINE. I would like to know the size ring it takes. As near as I can measure it would be about a 1.5mm x 38mm. I only have a piece of the old ring so it is hard to tell the diameter. Share this post Link to post Share on other sites
Wallfish 697 #2 Posted February 1, 2016 Unfortunately I don't have much experience with those engines and only own one, which I have never taken apart. I'll search through my documentation to try and find a size but may only find a part #. I would suggest you send a PM to member Webhead.(Joe Weber) He's not as active on here as he used to be but he might have the rings.You can also contact him through eBay as he has quite a few items up for sale now under Ohlsson Rice. His name on there is amcweb 1 Lee reacted to this Share this post Link to post Share on other sites
Lee 3 #3 Posted February 2, 2016 Thanks I just ordered some rings from overseas .5 sets for $11.89 with free shipping.So I have little to lose if wrong size but I measured my piece of ring I found in engine for thickness and measured piston and bore so I think they will fit .May need to grind some to get wright end clearance . I will post results once I get them and install. Thanks 2 Wallfish and nigel reacted to this Share this post Link to post Share on other sites
factory 487 #4 Posted February 7, 2016 The O&R part no. for the rings used on the Model 20A engine is 200023. Don't forget to clean out the remains of the air filter, as they disintegrate just as well as the earlier engines. David 1 Lee reacted to this Share this post Link to post Share on other sites
factory 487 #5 Posted February 7, 2016 Here is a advert from 1973 found online that has two O&R powered Lancaster chainsaws, the 20SLA Automatic that Lee has and the 15SLA Mini Automatic that I have. Also attached are some pictures of my smaller Lancaster 15SLA Mini Automatic with the 13B engine. The air filter is different to the standard ones fitted to O&R's, also the instructions aren't quite right as the chain oiler is automatic. David 4 pmackellow, Lee, Stormin and 1 other reacted to this Share this post Link to post Share on other sites
Lee 3 #6 Posted February 11, 2016 The rings came today and this evening I went to the garage and fitted them to the bore.I need to glaze the cylinder then try to figure out which way the blind bore cylinder fastens to the lower case.Its been about 28 years since I took it apart so It will be interesting putting it back to gather .It is very cold here in PA and my garage takes a while to warm up in this weather. Share this post Link to post Share on other sites
Lee 3 #7 Posted February 11, 2016 The O&R part no. for the rings used on the Model 20A engine is 200023. Don't forget to clean out the remains of the air filter, as they disintegrate just as well as the earlier engines. David Thanks I will do that. Unfortunately I don't have much experience with those engines and only own one, which I have never taken apart. I'll search through my documentation to try and find a size but may only find a part #. I would suggest you send a PM to member Webhead.(Joe Weber) He's not as active on here as he used to be but he might have the rings.You can also contact him through eBay as he has quite a few items up for sale now under Ohlsson Rice. His name on there is amcweb Thanks for the information. Share this post Link to post Share on other sites
Lee 3 #8 Posted February 13, 2016 Thanks I just ordered some rings from overseas .5 sets for $11.89 with free shipping.So I have little to lose if wrong size but I measured my piece of ring I found in engine for thickness and measured piston and bore so I think they will fit .May need to grind some to get wright end clearance . I will post results once I get them and install. Thanks Installed the piston and rings into the blind bore.No easy task with out the proper ring compressor .Trying to figure out where everything goes and the order in which it must be put together has taken some time.Sure could use a parts diagram although I am getting there.not sure what the presets are for the carb but this would make it a lot easier . May be a while to I get back to it because of honey do lists! 1 nigel reacted to this Share this post Link to post Share on other sites
Wallfish 697 #9 Posted February 13, 2016 I'm assuming this is a 20A engine. Here is a diagram of what I have. Let me know if you would like a better copy with a parts list and I can email one to you. 2 Lee and pmackellow reacted to this Share this post Link to post Share on other sites
Webhead 95 #10 Posted February 14, 2016 If that is the correct engine, I have many rebuild parts for it on Ebay right now. i also have many parts that I do not have listed, including rings, decompression valve, starter parts, crankshaft and many others. Let me know if you are need of anything and I can discount them from the Ebay prices. Share this post Link to post Share on other sites
factory 487 #11 Posted February 15, 2016 (edited) Sure could use a parts diagram although I am getting there.not sure what the presets are for the carb but this would make it a lot easier . I have scanned the pages from the model 20A maintenance manual that cover the carb, hope it helps. Model 20A Maintenance of Carb.pdf David Edited February 15, 2016 by factory Share this post Link to post Share on other sites
Lee 3 #12 Posted February 21, 2016 (edited) I'm assuming this is a 20A engine. Here is a diagram of what I have. Let me know if you would like a better copy with a parts list and I can email one to you. Wow thank You , I put it together tonight and just came in from garage to see what the points get set at and seen you diagram and it appears I got everything together wright. Just need to set points which I currently have set at 14 but have not seen a setting for them yet.I did check for spark and it is getting a nice blue spark.To late to run it because my garage is about 20 feet from a neighbors bedroom that is just across the alley. Ill take you up on the email of the parts list at your convenience. Does it say what the points get set at and the setting for the mag to flywheel clearance. Edited February 21, 2016 by Lee Share this post Link to post Share on other sites
Lee 3 #13 Posted February 21, 2016 I have scanned the pages from the model 20A maintenance manual that cover the carb, hope it helps. Model 20A Maintenance of Carb.pdf David Thanks Dave it helped a lot and I will save it. Share this post Link to post Share on other sites
factory 487 #14 Posted February 21, 2016 (edited) Wow thank You , I put it together tonight and just came in from garage to see what the points get set at and seen you diagram and it appears I got everything together wright. Just need to set points which I currently have set at 14 but have not seen a setting for them yet.I did check for spark and it is getting a nice blue spark.To late to run it because my garage is about 20 feet from a neighbors bedroom that is just across the alley. Ill take you up on the email of the parts list at your convenience. Does it say what the points get set at and the setting for the mag to flywheel clearance. From the O&R 20A manual; Points gap is 0.015" to 0.018" Coil to flywheel gap is 0.010" Spark plug gap is 0.025" The ESA 1973 parts manual gives the spark plug gap as 0.030" David Edited February 21, 2016 by factory 1 Lee reacted to this Share this post Link to post Share on other sites
Lee 3 #15 Posted February 21, 2016 From the O&R 20A manual; Points gap is 0.015" to 0.018" Coil to flywheel gap is 0.010" Spark plug gap is 0.025" The ESA 1973 parts manual gives the spark plug gap as 0.030" David Dave Thank You for that Info. I will get back to it Monday or so. All of the members here have been so helpful I hope I can some day return the favor. Share this post Link to post Share on other sites
Wallfish 697 #16 Posted February 28, 2016 Lee, I need an email address to send those files if you still want them Share this post Link to post Share on other sites
Lee 3 #17 Posted February 29, 2016 (edited) On 2/28/2016 at 12:37 PM, Wallfish said: Lee, I need an email address to send those files if you still want them Edit by @factory : email address removed to help prevent spam, it's best to send contact information by personal message (PM). Edited June 20, 2019 by factory Share this post Link to post Share on other sites
Lee 3 #19 Posted March 17, 2016 I am really stumped.I have it together and it has good compression as well as blue spark that will jump over 1/2" but will not fire at all. I even tried gas in the exhaust with not even a pop. I pulled plug and it is getting gas. I put plug in Snow blower again to make sure it fires and it does. Put it back in chain saw and nothing.At this point I am considering selling parts on E__Y . Share this post Link to post Share on other sites
Stormin 4,458 #20 Posted March 17, 2016 I know nothing about these engines, but to me it sounds as if the timing is well out. Share this post Link to post Share on other sites
Wallfish 697 #21 Posted March 18, 2016 Agree with Stormin. Pull the flywheel and check that key. or Bad gas maybe? I'll get some good pics of those engine pages for you this weekend, Sorry about that, it slipped my mind 1 Lee reacted to this Share this post Link to post Share on other sites
S1g 579 #22 Posted March 18, 2016 I'm not overly familiar with these but are the crankcase seals good? If not then it will not draw fuel properly. 1 Lee reacted to this Share this post Link to post Share on other sites
Lee 3 #23 Posted March 21, 2016 Agree with Stormin. Pull the flywheel and check that key. or Bad gas maybe? I'll get some good pics of those engine pages for you this weekend, Sorry about that, it slipped my mind The key looks good no marks .The gas is only 2 weeks old and is ethanol free. I'm not overly familiar with these but are the crankcase seals good? If not then it will not draw fuel properly. It is getting gas and the seal are tight .Thanks for suggestion.I am really stumped.My oldest son is coming down this week end and wants to take it with him and see what he can do.He said it is now a challenge . He has his own automotive repair garage and is better at trouble shooting then me. Share this post Link to post Share on other sites
Lee 3 #24 Posted March 21, 2016 The key looks good no marks .The gas is only 2 weeks old and is ethanol free. It is getting gas and the seal are tight .Thanks for suggestion.I am really stumped.My oldest son is coming down this week end and wants to take it with him and see what he can do.He said it is now a challenge . He has his own automotive repair garage and is better at trouble shooting then me. The crank shaft does on TDC move quit a bit with out the piston moving.So I pulled the cylinder off of piston and checked for play at the crank and can not see any at all.So I pulled rod and piston and checked for play in the rod to piston (wrist pin) and it is tight also.The mag can not be move to change timing just in and out to flywheel to st the 10 thousands clearance which I set with a non magnetic feelers gauge with magnet at mag forks. I can't help thinking it has something to do with the rod and piston not moving at top or bottom of stroke causing the timing to be off. Share this post Link to post Share on other sites