Here is a subject that never ends. I am finally getting my 216 back together after getting the cracked block welded. It is the first time I have had the luxury of replacing a rope seal with the engine in a stand and the crankshaft completely loose. Still a problematic process. I have at this time only the crank in place. The main bearings are plastigaged to spec and the shaft has rotated nicely, until today. Now I have installed the rope seal according to the many instructions found around this site. Still when I torque down the four caps to, well, only 90 ft lbs so far, the shaft is impossible to rotate. If I take off the rear cap with half the seal it is still impossible to rotate. I can see the rope peeking out around the lower half of the bearing cap. I am sure it is sealing well, but I am not sure I want to keep going until I feel this is done right. So far the harmonic balancer is off, so I am trying to turn it by wrestling with the counterweights on the crank.
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe
The last time I installed a rope seal, I made a tool from an old 4" diameter piston machined down to 3 7/8" which is the size of the seal surface on a stovebolt crankshaft, and used it to roll and pack the seal rope into place. I believe there is a picture of me using the tool in John's article on the buildup of his 261 engine. I used a piece of broomstick through the wrist pin hole as a handle for the packing tool. Roll the seal firmly into the block and the bearing cap and shape it to the exact radius of the crankshaft. Use some oil or assembly lubricant on the crankshaft- - - -a dry seal creates a great deal of drag.
Wrap a piece of thick leather around the crankshaft snout to keep from scarring it, and use a large pair of pliers or a pipe wrench to help turn the crankshaft. The seal will increase the turning torque a considerable amount. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
It Sounds like a great idea, Jerry, but there aren't any old pistons lying around my shop. I do have pipe mandrels (basically a collection of steel pipes in many dimensions). I used the nearest to 3 7/8 to get a little extra press on forming the seal. The term "exact" doesn't apply to most of the work I do. There seems to be a lot more rope than there is groove. That is of course the point of a seal. It would seem I will need to lift the crankshaft again tomorrow and see if I can press the rope farther into the groove.
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe
I've seen similar tools turned from hard wood such as red oak or maple and a rubber mallet used to shape the seal. The main idea is to form the sealing surface of the rope close to the radius of the crankshaft before installing the crank. Obviously, the ends of the seal rope need to be trimmed off flush with the block and the bearing cap so nothing interferes with the mating of those two surfaces. I use a little non-hardening gasket sealer there to prevent a seep leak at the parting line. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
You can screw some bolts or studs into the flywheel mount holes and use a long bar to turn. Keep the bar as close to the crankshaft flange as possible to minimize the stress on the bolts. Probably will never do another Stovebolt engine but if I do I'll set my boring bar up as Jerry described to get rid of that %*#& rope.
I use the crank shaft to size the rope. With one piece of seal in the block, lower the crank in the block, use a rubber hammer to knock the crank down against the bearing. Pull the crank back out, carefully pull the rope out and add the second piece. Repeat the forming with rubber hammer, pull crank, trim seal. Add first piece of formed seal to cap, press it in place, trim, and assemble. The crank should have a pretty heavy break away torque, but once rotating, it shouldn't be that tight. You will need more the counter weights to spin crank. Use a bar between two flywheel bolts.
So the seal is in place, for better or worse. The upper half seemed pretty well pressed into the groove. The half seal in the cap not as good. I formed it over the crankshaft a bit like Joe describes, but I used clamps to press the cap into place, then removed the cap, reformed it, pressed again, the whole process quite a few times. The pictures show a bit. Using the two bolts and a crowbar I was able to keep the crank turning ok. It seems ok now. I can't imagine how I have done this two or three times lying on my back under the the beast with the crank in place. One remark, probably best in another thread, is how the heck does one keep metal shavings caused by the lockwashers from falling into the somewhat clean block while torquing and untorquing the caps during the plastigage process? I suppose the best would be to temporarily replace the lock washers with other washers during the process, but I have never heard anyone recommend this.
Karl
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe
Why are there lockwashers on the main bearing bolts in the first place? Maybe a hardened steel SAE flat washer might be OK, but it's the torque on the bolt, not a lock washer, that keeps main bearing, rod bearing, and head bolts tight. Split-type lock washers in particular have a nasty habit of spreading out under heavy torque, and allowing a bolt to loosen itself. Star-shaped washers create metal shavings that don't need to be in the crankcase. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
