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Discussion Starter #1
Ok so heres the deal, I'm in progress with rebuilding my engine. I have all of the pistons in place, the connecting rods torqued, and the engine wont budge when I try to turn the crank. I have lubed the connecting rods where they meet the crankshaft but it wont turn. :banghead

I didn't take the crankshaft out, so it should still be smooth. It turned before the rods were torqued.

Whats wrong? Any help is appreciated
 

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dosdovi said:
Ok so heres the deal, I'm in progress with rebuilding my engine. I have all of the pistons in place, the connecting rods torqued, and the engine wont budge when I try to turn the crank. I have lubed the connecting rods where they meet the crankshaft but it wont turn. :banghead

I didn't take the crankshaft out, so it should still be smooth. It turned before the rods were torqued.

Whats wrong? Any help is appreciated
remove the rods and pistons. reinstall them one at a time, rotating the crankcrshaft 1 rev for each one isntalled. if it stops you know which rod/piston caused it.
 

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Stuck like a MoFo
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You should have plasti gauged each rod/main cap when replacing the bearings so you know if they were within spec. YOu can't just go by one. Also like Zach said you should rotate the crank to make sure the crank isn't tighter in one spot then the other.

BTW if you want to go cheap on the bearings accoriing to Ford specs and my actual experiances you can mix bearing halves to get the proper clearences.

Forgot- are you using the proper tq for the rods, IIRc it was like 40-50ft lbs and around 70 for the mains on most but make sure you got the right spec
 

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Ex Navy Nuke
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What did you lube the bearings/journals with? If all you used was motor oil then it probably won't turn. Did you plastigage all the bearings before final assembly? You need to used engine assembly lube on all the bearings when putting it back together.
 

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Discussion Starter #5
Well I dont think that it is one single piston that is causing the problem. As I add pistons it gets progressively harder to rotate the crank. When they are torqued to 45 ft-lbs. I cannot rotate the crank at all.
 

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Discussion Starter #6
Ok so haha funny story. I found out that the bearings are for a 302. And I haven't had a 302 since last year, and summit couldn't have known that because I said 351... I guess Ill go get some from AZ
 

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Lick my balls
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Plastigauge (before you add any lubricant) is your friend.
 

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Steve83 said:
Why not just use tin foil? :twak
you mean you cant stack tinfoil behind bearings?
 

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RLKBOB said:
What did you lube the bearings/journals with? If all you used was motor oil then it probably won't turn. Did you plastigage all the bearings before final assembly? You need to used engine assembly lube on all the bearings when putting it back together.

Been rebuilding engines my whole life. Always used motor oil on the bearings. Always had the engines turn just fine. Never had a bearing failure after a rebuild. Why do you say you cant use motor oil? Most manuals tell you to lube the bearings with motor oil. Just curious as to why you say it wont turn when I have done it this way my whole life. ...
 

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dgmid61 said:
Been rebuilding engines my whole life. Always used motor oil on the bearings. Always had the engines turn just fine. Never had a bearing failure after a rebuild. Why do you say you cant use motor oil? Most manuals tell you to lube the bearings with motor oil. Just curious as to why you say it wont turn when I have done it this way my whole life. ...
Ive always used honey oil. you want something thick like mollasses so you know it is lubed up while you try starting it.
 

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Discussion Starter #11
Ok it wont turn now. It turned fine with the bearings being torqued but now that the head is on I got nothing. I'm just torqueing that nut beyond what I believed to be physically possible.

Is this normal or is it just because is so friggin cold outside? What should I do to remedy the situation?
 

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im gunna say break it apart again and measure your pistons, somthing is not right with them maybe too big or now that i think of it did you check you cylinder walls? i mean measure them when i say that
 

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what are you useing to turn it with?, remember by putting the head on you should now have compression, and will be harder to turn...and what nut are you talking about?
 

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So what ended being wrong that you were now able to turn the crank with the caps torqued down, when you couldn't before? You need to explain, step by step what it is you did to solve the problem and then describe what you did up until, and including how you installed your heads.
 

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Bolting on the heads shoudn't matter one bit unless you have the plugs installed. Then yes you will have compression.

FWIW I've always used straight 50W for the crank and rod bearings durring assembly unless I knew that it'll sit a while before I started it up. Only in that case would I use something thicker (like assembly lube).

On a side note you really need to check your bearing clearances with plastigauge, and your ring end gaps with a feeler gauge at the top, middle and bottom of each bore for each ring before they're installed on the pistons.

The whole rotating assembly should'nt take any more than 30ft/lbs (ballpark) on the crank to overcome the friction of all the assembled parts, and should rotate smoothly.

Hope this helps.

-Paul
 

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Holly Fook!! :shocked

I just reread your post where you said this:
I found out that the bearings are for a 302. And I haven't had a 302 since last year, and summit couldn't have known that because I said 351...
OK.... how the fook did you even get the crank on the mains.. or the rods on for that matter with bearings for a 302? :twak

Did having to litterally pry the damn things open raise any kind of flag that maybe something just wasn't right?

Dude... hate to say it but you just need to step away from the thing... do some reading... then maybe... just maybe try this all over again from the begining.


:doh0715:

edited to add that this is my 500th post! :rockon

I pwN teh interwebs! :chili:
 

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Dead Horse
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ValkariaKid said:
edited to add that this is my 500th post! :rockon
go create a new thread bragging about how many post you have
 

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Nah.... I'll just be a ho in this one because I'm too lazy.
:goodfinge
 

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waltman said:
Ive always used honey oil. you want something thick like mollasses so you know it is lubed up while you try starting it.
30w is what ford recomends in their book. But as long as you just get some motor oil on there you will be fine AS long as you prime the motor liek you are suppose to anyway.

Please prime your motor so your work is wasted.
 

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I use "assembly lube" the cherry syrup lookin stuff.
 
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