Sooo, I spent a few hours re-arrainging stuff and putting a new shelf up in the shop, and then casually snuck up on the Pollinator motor to install a rod and piston... kinda like taking a kid in for a tontsillectomy... "Geez, youll get all the ice cream youve ever wanted..."
Washed the ring compressor and got that on, put some hose nips on the studs and shot the bastard home. It was just like somebody came over and did it for me!
Had the bearings scraped yesterday for a >75% contact (book calls for 50%)installed a piece of plastigage and snugged the cap down. Pulled it up and found .0008-.001" clearance. All the book says is a proper fit will allow you to tap the rod from side to side on the journal. The caps are getting dippers put on.
Now for the MAN question... is the .0008 too tight? BTW... this is #4 and had .045" shims in it. My numbers called for .030" and pulled out the .015, pretty close with .001" to spare. The alternative, if too tite is to pull the .030. install a .015 PLUS find and make an additional.016-.017
SURVEY SEZ.... ws
This is mid-way through the scraping
This is a typical cap contact area...
I don't think .0008 is too tight, especially in a scraped bearing where you haven't got 100% contact anyway. I find too tight to be when it drags.
Thanks Jerry! Im kinda used to precision bearings,(insert shells) with generally .0015 cleance. I guess I should just oil it up, snug it down and try to roll the crank a few turns... ws
I would add a shim to try to get .0015. .0008 is a bit tight and might gald the babbitt on startup.
Im gonna see if theres any combinations with the other rods to help improve that .0008 by .001 or so. Theres shims all over town on these rods... ws
Before the days of plastigage for checking, the rule of thumb was on scraped bearings that the con-rod would gently fall with the weight of the cast iron piston.
I think we have a winner Kerry! Im gonna pull that rod out today and bolt it up free standing and see what it feels like. Thats the way I blue fitted the bearings the other day. Totally able to get at everything including rolling the crank flange with my fingers... pics to follow.
I'll hafta use a little "juris prudence" as I have aluminum pistons on the "drop" test, but I would guess the feel can be felt (?)! Thanks! Sometimes we forget how things were done (or couldve been done) in days of old when Fritz the mechanic only had a lug wrench and a T-1917 band wrench!! LOL ws
End of round 1... pollinator 1, Willy 0.
Went out to turn the heat on and pulled the slug outa da jug, clamped the rod back on to the crank, and VOILA! LOCKED UP TIGHT. Cracked the nuts loose like one flat and shes' a hunkey dory. So now, what the plan is, is to put a feeler gage tip under each side and tighten for the feel again. I think the skinniest feelers I have here are about .0015. Anything less than that is a cellophane wrapper off of a pack of spuds. I can see where this is headed!!! ws
When I workd for an old Model T mechanic, he would fit the rods with the crank out of the engine. He would tighten them up fairly snug, then hit the rod/cap with a lead mallet. That would usually loosen them some. Then you can play around with the shims or use Bon/Ami or Timesaver to finish.
In the old days we didn't have plastigage. A bit of newspaper worked or if that was too much bother we just filed till everything was snug. There were those who felt about filing as they did about fertilizer, if a little bit was good a whole bunch was better. When it was overdone the car could not be cranked so it would have to be towed to get it started. This usually worked. However sometimes it didn't. Once I remember a car getting towed but when the driver, trying to start the engine, put it in gear the rear wheels just slid in the gravel. They tried again when they got to pavement. This time the tow car pulled the front axle out from under the car.
Another time a neighbor tightened his rod bearings, hooked a chain to the front of his car and talked another neighbor into towing him. As he was towing him the chain broke and the recoil caused the chain to smash into the rear of the towing car, breaking the rear window. There was a terrible argument. I left when the fist fight started.