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Another update on the Simplicity.


eugenedrago

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I pulled the motor this morning. I checked the valves and their lash to be 10 and 21 thou on the intake and exhaust respectively. They are showing a little of out of tolerance but should come in a little once I lap them. I think I can rule out lash as my engine woes. I also put on a new coil so I should be able to rule out this as well. Condenser and new head gasket will go on after I figure out what is up with my rings and cylinder. I am still a little confused why I get such a range on the compression tests. 70 psi cold and 110 psi up to temp. When I pulled the head today the was a considerable amount of oil on top of the piston. More than just a "normal coating" and to the point where it "pooled" to one side when you tilted the motor a bit. That would explain some of the smoke issues for sure. Obviously I will ck the specs when I pull the piston. I am wondering if this is why my compression readings are so much higher when she is up to temp. If the cylinder is getting excess oil in there that could explain both the higher comp levels and possible the engine sickness I am experiencing after some run time. Are my rings that bad? Is there any possibility that the breather is not acting properly and I am getting excessive crank case pressure thus "pushing" oil up stairs? In any event I will find out more tomorrow. Thank you all again for your help and support on this. I look forward to any thoughts or criticism to help keep me focused. Gene.
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Anybody have thoughts on the possibility that the breather is not acting properly and I am getting excessive crank case pressure thus "pushing" oil up stairs? I just pulled the piston out and the rings are all free. Also does anybody now how to find or come up with the tolerances on the rings and cylinder? Thanks and good night all. Gene
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wow - you have threads all over the place. Had to go reading other threads to follow the story. I am not the expert mechanic, I am the 'armchair mechanic'. Having said that, I am wondering if the head is warped. You mentioned having to tighten head bolts, and you replaced gasket, etc. But I am wondering if a warped head would allow oil to sneak into the cylinder when things are hot. Possibly due to head leakage when hot, creating vacuuum to suck in oil. ? Any sign of oil spray on sides of head? There was a recent post by Al Eden. He mentioned this warp head idea and talked about sanding it on a smooth flat glass surface to offset slight warpage. The bolt areas are the points that get sanded off first. And the sanding leaves grooves for gasket seal to grip. That post was just a couple days ago - can't remember what thread it was in. Maybe someone else can. My shot in the dark. But many calls for valve clearance, condensor, and coil by several people. You gotta be getting close. I am very impressed with your slow methodical approach, and I know you are in process of following these suggestions. Also, a SUDDEN intro of oil into the comb chamber will kill a running engine at low rpm - I used to use trans fluid thru the carb on my old chevy, as an instant tuneup - and it had to be done at high rpm to prevent stalling. Keep at it. You, or we, will work it out. Just my thoughts. sm03 Nice tractor, saw the vid, welcome to the club. Peace.
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Thanks Graham, I did read that post on running the head across the glass with sand paper to see if the head was flat. I believe the head is true but will use this method and double ck. I am pretty sure that originally I never torqued the head bolts properly. Update: I also believe that my breather is working as it seems to let air out and not in. I ran a rubber hose up to it through the bottom of the block and was able to blow air through and when I drew drew back in she sealed. You can here it "popping" when you spin the fly wheel by hand when she is all together. So I think I can rule out excess pressure from the crank case causing the excess oil I found on top of the piston when I pulled the head. I am amazed that the rings and piston looked so good when I pulled them last night. I realize that looks mean nothing really here, but I thought with the amount of oil I saw on top of the piston I would have had a stuck ring or to or some serious scoring. A little at a time... Thank you all yet again!
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My top ring end gap is 69 thou and the bottom ring was 48 thou. I think this could explain the oil I saw "pooling" on top to the piston when I pulled the head yesterday. Gene.
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I am not certain about the gap on the rings, sounds a bit much, though. BUT, I will say, that since you now have the rings out of the bore and likely off the piston, there is no need at all to reuse them, rather buy a new set for installation. Check the bore at the top, down in the center of stroke, and at the bottom, then check your bore against original spec to see how bad the cylinder is worn. I haven't followed your posts, but started here with this one. You seem to be taking a shotgun approach to a situation, and should come across the initial problem as systematic as you seem to be approaching it. If the engine is a cast iron bore, new chrome rings might solve the whole problem. Many do not like chrome, but in cast, I would consider nothing else, as the chrome will not wear the cast as much as moly. Yes, chrome takes a bit longer to seat, and your oil use will continue somewhat for a while
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