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Old Feb 13, 2012, 02:42 PM
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hard starting OS 61SF ring


I have recently acquired an OS 61 SF ring, seems to be in good shape-however, it will not hand start and requires from 10 to 30 seconds with my sullivan starter. I can see fuel in the line, in fact will pull some up with a finger chocking the carb and hand flip. Glow plug is new and have changed-no difference. What are the chances of it not being broken in? I've bench run it approx. 20 minutes. Once it starts it has great power and excellent throttle response. Currently running Omega 10% with 12/8 wood prop.
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Old Feb 13, 2012, 03:26 PM
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Enough power to plug?


You might try removing the glow plug and checking the lit plug visually, it may not be getting enough power. This is why I like a power panel, you can vary the power to the plug (within reason) to suit the needs of the engine.
Old Feb 13, 2012, 10:04 PM
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I don't have a power panel, but will try a different glow connection. Thanks, I was wrong re: fuel brand-it is Sig 10%.
Old Feb 14, 2012, 09:50 AM
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What is the appearance of the engine? Does it show signs of being well used, like Castor discoloration on the engine/muffler? That can kinda gives you a sense of newness. I always suspect it is a well used engine and go from there.

It might need a new ring. Sounds like it needs a good internal coating of oil to build up compression to fire. Once running, there is sufficient oil to keep the compression up, temp expansion, etc. to sort of fill in the gaps so to speak.

You can get a new ring from Frank Bowmsn, the "ringmaster." Sort of inexpensive overhaul for an otherwise great engine. I have its little brother, the SF 46 and it runs a like a champion.
Old Feb 14, 2012, 11:56 AM
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The engine appears new, compression is good-prop bounces quite alot after a flip. It would not run 4 cycle at first, but seems better now-I've run it approx 20 minutes, attempting to 4 cycle with short 2 cycle runs intertwined. I appreciate the name of the ring man-that could come in handy in the future-does he have a web site? I had an 61 sf abc and it would start and run perfectly-until the chrome peeled and I couldn't get repair parts.
Thanks
Old Feb 15, 2012, 04:57 AM
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qtrsaw,

I'm thinking glow plug is too cold. An OS #8 or equivelant may be to cold try the OS #A-5 or the new designation
Old Feb 15, 2012, 07:18 AM
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I will try that, no hobby shops in rural MN, so will have to wait until my next Tower order. I have run at least a quart of fuel through it so far, and it seems to be improving-yesterday I got it started by hand. Another subject: I mentioned an ABC 61 SF with peeled chrome in the cyl. and wondered what the secret is to remove the cyl. liner?
Old Feb 15, 2012, 05:03 PM
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TigreJohn
Remove the head, backplate, muffler, and carb. Place in oven when wife not home at 250 to 300 degrees for about 20 minutes. Sacrifice a popsicle stick, split tongue depressor, or a toothbrush handle and stick it into the exhaust port. Rotate crankshaft and it should lift the liner far enough for you to pull it out while it is still hot.

Actually, if you have a peeled liner, stick anything you want into the exhaust port that the piston can push on.
Old Feb 15, 2012, 06:07 PM
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Thanks, really good advice-especially re:wife. I'll give it a try.
Old Feb 15, 2012, 08:06 PM
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Love the toothbrush handle suggestion. Now I know a "second life" use for my toothbrush.
Old Feb 15, 2012, 08:25 PM
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Easiest task first. Remove the glow plug, attach the driver and look at the plug. Is it glowing brightly or just dimmly?
Old Feb 16, 2012, 02:28 AM
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Quote:
Originally Posted by jjkupinski View Post
Remove the head, backplate, muffler, and carb. Place in oven when wife not home at 250 to 300 degrees for about 20 minutes. Sacrifice a popsicle stick, split tongue depressor, or a toothbrush handle and stick it into the exhaust port. Rotate crankshaft and it should lift the liner far enough for you to pull it out while it is still hot.

Actually, if you have a peeled liner, stick anything you want into the exhaust port that the piston can push on.
He said it was a ringed 61. Liner can't peel
Old Feb 16, 2012, 02:02 PM
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TigreJohn
He said he also had an ABC in post 5.
Old Feb 16, 2012, 06:04 PM
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I believe you are both correct. The engine in question is said to be ringed AND he has had an engine with an ABN cylinder that peeled. Not the same engine, I believe.
Old Feb 16, 2012, 06:54 PM
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Yes, two different engines. Finally, got this one to run quite well-took almost 2 quarts of fuel, but starts fairly well, idles and responds without hesitation-think it will be a great engine.
Thanks for all the help.


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