All Small Six 200 6 rebuild steps

This relates to all small sixes
Well, I am not getting a smooth easy rotation. I took all the caps off and used just number 4 cap and when I tighten up to say 60 ft lbs the crank will not rotate easily. I have to use a 2 ft bar between two bolts on the flywheel end to rotate it. The only thing maybe is I am using that engine lube instead of engine oil. I have some 10-30 so maybe that will help, I will use that instead, I also used the plastigage, see pics. The green went to 0.025 mm and the red to 0.051 mm. The bearings are a federal mogul made in Mexico. I know these need to be tight, but jeez this is crazy and that rope, I can see why drag 200 went neoprene. Apparently what I need is Felpro BS30135 but they are out everywhere. This is just nuts. I don’t want to reassemble and install the whole engine and then see the starter freeze…right? That crank is too tight.
 

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Looks like you have .020 over size Main Bearings. What dose the Crankshaft Measure has it been cut down under size from stock?

Not the best dealing with MM but the one the with Red Plastic Gauge (PG) .051 is suppose to convert over to a 0.002008 that should be ok. the Green PG .025 = 0.0009843 this is on the tighter side but should still be within the Fords Min. spec. Still that's quite an range difference between the two of them. I would like to see more like a .0012 to .0015, and .002 to .0025 is closer to the Max for a stock type Street engine rebuild and hope for more consistency between them. Some times you can switch bearing half's to get them to match a little better. Do you have a way to measure each Crankshaft Main Through Size?
 
They were on the same number 4 rod bearing. I also have some blue plastic gage but did not use. I have a caliper. I will measure all seven tomorrow front to rear, you want inch or mm?
 
After all these Decades of working with US system I think pretty much automatically in Thousands and Hundreds of an inch but with a little effort I can Convert the MM over. Its funny the Only Metric's I got very used to were CC's.
 
Bubba: Front. 2.228 2.227 2.227 2.228 2.2224 2.226 2.224 rear

spec shows 2.2468. So unless the 0.020. On each bearing, then it would be 0.040 and too tight?

my torque wrench is perhaps inaccurate? Maybe I will take down to a local shop and they can check it?
 

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Just for fun I put the caps on #1. #4 #7 and tightened up to about 20 ft pound, just snug without crank,

measured #1 2.225. #4 2.226 and #7 2.222

what is your expert advise?
 

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Interesting by those measurements there is no reason that the crank doesn't turn very easy.

1. 003 clearance
4. 002 clearance
7. 002 clearance

I think you should also check the other Main measurements. You could also lay the crank in the Block and torque them down to spec for the #1, #4, and the #7 then test how the Crank turns. If ok then add another Main Cap and torque down and retest until you find out which one or more maybe causing the trouble. Now are these Main Caps the original one's to this engine block? And are they installed in the correct locations by number and with the Arrow pointing forward as "drag-200stang" had mentioned in his above post?
 
Interesting by those measurements there is no reason that the crank doesn't turn very easy.

1. 003 clearance
4. 002 clearance
7. 002 clearance

I think you should also check the other Main measurements. You could also lay the crank in the Block and torque them down to spec for the #1, #4, and the #7 then test how the Crank turns. If ok then add another Main Cap and torque down and retest until you find out which one or more maybe causing the trouble. Now are these Main Caps the original one's to this engine block? And are they installed in the correct locations by number and with the Arrow pointing forward as "drag-200stang" had mentioned in his above post?
As far as I know these are original. I think you misinterpret. Ie: the crank at front race measures 2.228”. The opening (picture) measures 2.225. So there is shortfall of .003”.
 
I'll say, ok so yes a Stock 200 Six Crankshaft Main Throw measures 2.2486! At 2.228 we are at a difference of .0206. So this crankshaft was turned under sized .020, and did they also supply the oversized bearings? With it being to tight by .003 then it can only be something like the wrong Main Bearing size was supplied to you or that they didn't get the Main Throw sizes quite right when they were grinding it under size and polishing it. So it looks like they either need to do some more polishing on it if the bearing are right or try another set of bearings.
 
Wme, yes I agree shows. 0.0206. When I remove the rope seal completely from block and secure crank with center cap I can spin easily by hand, so I think the parts are right, it is just that damn‘d rope seal Causing the frictionI have two choices basically.

I can wait on the Felpro 30135 neoprene to get in stock, or perhaps I can see if the 30136 can be trimmmed down to fit.

or I can assemble crank with pistons with things loose, and force that rope seal in as tight as I can, also attach timing gears and chain. Then torque it all down and cross my fingers the starter does not jam. Maybe test it on the bench.

opinions?
 
Interesting by those measurements there is no reason that the crank doesn't turn very easy.

1. 003 clearance
4. 002 clearance
7. 002 clearance

I think you should also check the other Main measurements. You could also lay the crank in the Block and torque them down to spec for the #1, #4, and the #7 then test how the Crank turns. If ok then add another Main Cap and torque down and retest until you find out which one or more maybe causing the trouble. Now are these Main Caps the original one's to this engine block? And are they installed in the correct locations by number and with the Arrow pointing forward as "drag-200stang" had mentioned in his above post?
Joe, what is the answer to the last question are we supposed to guess that you are following? you make it hard to help. Read what is posted all of it. Sorry for the rant:)
 
So there still might be some miscommunication on the main bearing measurements, if both half's of the Rope seal were removed and there was a .002 to .003 tighter measurement on the main bearings compared to the crankshaft's throws diameter it would be locked up tight when the caps are bolted down tight. If there was as I was thinking .002 to .003 of clearance on the Main bearings than the Crankshaft would spin easy with a just a flick of your hand. Also you did the Plastic Gauge Clearance Testing in your the above post and it shows that you do have some amount of Clearance that should work and you could alyways swap some of the bearing half's around from the looser one to the tightest ones.

On the Rope Seal install I also gave you the way to do it in with a few basic hand tools in the above post (see below) did you happen do it like that? If so when the Rear main Cap is installed and Torqued down to spec., it will be tight but still turn and it wont be to tight to harm the starter. Over time the Rope Rear Seal will compress and conform into the blocks and main caps rear Groves and will eventually loosen up some with use. It's ok a lot of people have some trouble the first time doing the Rope Seals they aren't that hard for me as I have been doing them since the early 1960's they were used in most older engines going back into the 1920's. Yes if I had my choice though I would always like to use the Neoprene Rear Main Seals. When they came out in the late 1960's early 1970's I would use them in every engine that they made them for since it's like an extra bonus of getting a little free Horsepower, but right now its a parts availability issue. Good luck. Edited

Installing a Rope Seal

"A rope Seal gets pressed / worked into the Short Block's Rear Main Seal Grove and the Rear Main Cap Grove snugly, I use a Large enough Diameter Socket that closely matches the Crankshafts Main Bearing Surface Diameter to push the Rope Seal snugly down into the grove by hand and than also tapping it in a little more with a Composite Dead Blow or a Brass Hammer to compress them well into the Grove. The Rope Seals are not rotated in the Grove (only the Neoprene type Seals are clocked in the groves note that these seals are now currently very hard to find). The Rope Seals are then cut down to about 1/32 to 1/16 of an inch above so they are no lower than flush with the Blocks Main Saddle Parting Line and the Rear Main Cap Parting Line after they have been tightly fitted into the Block and the Main Cap groves. Now after you have finished installing of the Rope Seals and the Main Cap is installed and Torqued down correctly then your ready for the rest of the Short Blocks Assembly." Edited
 
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Bubba, thanks and it does seem to spin easily without the rope seal at all, just the 7 caps. So I think the parts are right. Using motor oil seemed to help some above the assembly lube. That rope seal…..I think I am going give things a rest a month and maybe I can track down a neoprene type. Or, I may just try assembling it and trying the starter Before I put the engine in the car. At least a couple spins.
 
We yes I am using motor oil. Curiously on the rear part of crank at the mating point of the rope seal there are slight diagonal cuts, I assume these act to “throw” the oil back into the engine as it spins. I may try again if I get my patience up. Would be nice if there was a continuous loop neoprene type. Maybe I will design something.
 
The Felpro 30136 Rear Main Seal is made for use in the larger 250 Six & the 289, 302, 351's etc. V8's (and some others) and has a much larger Diameter. Yes these seals have been tried several times by some site members trying to trim them down to fit into a the 200 Six and it doesn't work out ending up in wasted money and time. If you are really wanting to go to a Neoprene Rear Main Seal than this might be the only way their is to go right now it's a much closer match to diameter size of the 170 / 200 Six Rear Main, good luck. https://fordsix.com/threads/rear-main-seal-search-problems-and-solutions-i-hope.83442/
 
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