Need Help, Pistons binding.

M

MattK67

New Member

Jun 30, 2004

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Aug 17, 2005

#1

• Aug 17, 2005

• #1

I went back and locktited and torqued all of the nuts on my connecting rods last night and now I can't get the crank to turn. I had one of the rod bearings slip, so I straightened it back out and it seemed to fix the problem. I finished torqueing everything down and now the crank is stuck again. I went back through and took all of the rods off and checked the bearings one by one, retorqued them, and it's still seized up. Anyone have any idea what could be binding up?

 

krash kendall

Active Member

Nov 19, 2004

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Aldergrove, B.C. Canada

Aug 17, 2005

#2

• Aug 17, 2005

• #2

Did you assembly lube them, or are you trying to turn them dry?

 

G

grego37

New Member

May 12, 2004

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Fresno CA

Aug 17, 2005

#3

• Aug 17, 2005

• #3

Does the crank spin by hand in the block with all the main caps torqued down?

Nedd more info.
New rebuild?
block recently bored?
new pistons / rings?
Piston to cyl. wall clearance?
rod bearing clearance?
are you torqueing evenly in steps?

 

66P51GT

New Member

Nov 7, 2003

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Cerritos, CA

Aug 17, 2005

#4

• Aug 17, 2005

• #4

Did you use plasti-gauge on the rod bearings? If the clearances are too tight it will keep you from being able to rotate the assembly. Also, use plenty of lube on the bearing surfaces. I used Lucas oil on the pistons.

 

6

66bluepony

New Member

Nov 7, 2004

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Aug 17, 2005

#5

• Aug 17, 2005

• #5

No No

You should not use locktite on rod bolt or bearings. Any bearings damaged should be replaced not straigntened out. I would remove all the rods and clean them and the bearings. Use engine oil on the threads or your torque readings will be thrown off and you will never know the real torque value.

 

1

10secgoal

Active Member

Dec 1, 2003

2,801

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San Diego

Aug 17, 2005

#6

• Aug 17, 2005

• #6

66P51GT said:

Did you use plasti-gauge on the rod bearings? If the clearances are too tight it will keep you from being able to rotate the assembly.

Click to expand...

I would almost promise this is the problem.

 

brianj5600

Active Member

Sep 19, 2003

1,964

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39

Middle TN

Aug 17, 2005

#7

• Aug 17, 2005

• #7

Hey Matt, can you fix a dryer? I'm just down the road, maybe we can swap out some work. I might be able to get by and see what is up sometime soon, if you need it.

 

stanger53

New Member

Jun 24, 2005

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San Antonio, Texas

Aug 17, 2005

#8

• Aug 17, 2005

• #8

If the crank turns freely with the mains tightened down, the bearings are mounted correctly and are the correct size for the crank journals, then you probably have the rods on the crank backwards.
Rods only fit on a crank journal one way due to the offset and chamfer of the bearing. Sometimes a shop will install the pistons on the rods wrong. You install the pistons correctly but the rods are 180' off. Then when you tighten the rod bolts, the bearing jams into the fillet of the crank journal and binds.

 

dennis112

15 Year Member

May 15, 2005

1,561

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79

Amish Wonderland of Central PA.

Aug 18, 2005

#9

• Aug 18, 2005

• #9

Are the rod caps being installed in the proper direction?

Are the rod bearings from the same set? Check the rear of them--do they all have the same "size" stamped on them?

Was the crank reground and are the bearings correct for the regrind?

If all is OK then get some plastic guage and check the rod bearing clearance of each journal/rod. Do them one at a time . If in spec, move on to the next hole/rod.

 

SoCalCruising

Founding Member

Jul 25, 2000

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SoCal

Aug 18, 2005

#10

• Aug 18, 2005

• #10

Agree with Stanger53. Check that the large bearing champfer is facing the crank counterweight face on each crank throw. Been there, done that.

 

brianj5600

Active Member

Sep 19, 2003

1,964

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Middle TN

Aug 18, 2005

#11

• Aug 18, 2005

• #11

How about the thrust bearing, is it in #3 main?

 

1

10secgoal

Active Member

Dec 1, 2003

2,801

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San Diego

Aug 18, 2005

#12

• Aug 18, 2005

• #12

SoCalCruising said:

Been there, done that.

Click to expand...

Don't you just hate learning, and knowing stuff by experience ?

 

RFMustangGT

Member

Apr 4, 2005

294

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Knoxville,TN

Aug 19, 2005

#13

• Aug 19, 2005

• #13

I had mine bind up on me but it was from th eoil pump shaft getting stuck.

 

SoCalCruising

Founding Member

Jul 25, 2000

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47

SoCal

Aug 29, 2005

#14

• Aug 29, 2005

• #14

So, what was the problem?