Barely turns!!---Normal??

Not much info.

What about the 4th ? And how about the mains ?

Have you tried loosening all the caps slightly on all the rods and mains and see what that does ?

What has recently been done ? New rings maybe ? Has this monster been sitting for a long time ?
 
engine ran ok when I got it.---low compression 45 psi. eng sat for 40 years. no ridge in cyls---finish hone- new pistons and rings. did not touch mains. Is this normal ? may have to pull to start
 
Disconnect or merely loosen all caps, tighten one main at a time and rotate after each, continue on with rods until you find out where the drag is. If you find a tight journal, loosen and continue in case more than one is tight.
And of course it is possible that drag is upstairs and coming from ring or piston misfit.
 
Many times on an engine that has some use the rod journals may not be round anymore. This condition will give a false reading with plastigage. You may actually be tighter during part of the crank revolution. The same is true of the mains but I have not seen as much of a difference in main journal roundness as I have at the rod journals. Something to consider or check if you have not placed a micrometer on the journals. Solution...loosen them a bit.
Good Day!
 
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Are you turning over with the starter or by hand? I recently helped someone who had worked on his engine and trying to start, it would just barely turn. What I found was his timing was off and firing too soon. Cranking with the ignition off spun really well. We retimed and all OK.
 
Thanks for all the good advice. I think .001 is to tight and the journals are not round. I will go for .001-75 and should free up---will let you all know----
 
fourbangerbob said:
Thanks for all the good advice. I think .001 is to tight and the journals are not round. I will go for .001-75 and should free up---will let you all know----
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Hey Bob,
Why not go with what Herm said, i.e.- .0015 ? That IS what Ford set them at , if I remember correctly.

All good thoughts given here , and the info that you gave about NO ridge ring says a lot also. The mains may have been set just right and I would not disturb those , until you find that all else is OK !

I'm wondering...did you put NEW rope seals in block and pan ? If so, you will get a lot of resistance after either or both of these are installed..which , IMO, you can understand will happen. Or is your hard turning without these seals ?

For an example, I just put a short block together ....mains/rods at .0015. ALL turned well, until I installed new rope seals at front of crank...wow, what resistance then !!

Here is a 'tip' that I got from a race engine builder. after EVERY step of assembly , turn engine over by hand twice to see what if any problem exists. Works for me..
 
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Dave in MN said:
Many times on an engine that has some use the rod journals may not be round anymore. This condition will give a false reading with plastigage. You may actually be tighter during part of the crank revolution. The same is true of the mains but I have not seen as much of a difference in main journal roundness as I have at the rod journals. Something to consider or check if you have not placed a micrometer on the journals. Solution...loosen them a bit.
Good Day!
Click to expand...

This EXACTLY the case on my original red Sears engine which came with the car. After some more wear, I would set the crank up so that it just "bind" as it passed the tight spot - but a push with the hand would send it past.

This an engine which had acquired the classic "whuppa-whuppa" sound when idling. And rods about 3 thou egg shaped.

I guess I used the engine until it seemed like the whuppa whuppa was just a little too much. Traveling down the Mid-Cape Highway at 55 plus (3.54 rear) suddingly the whuppa-whuppa grew EXTREME. A step change in audibility. Not thrown a rod but alarming in it's contemplation.

I nursed it home not exceeding 35. A tear down revealed that I had lost one of the rod nuts and the rod cap was being held by only one side.

"Engiine done" I thought to myself.

I found the missing nut - AND the pieces of the cotter pin - in the bottom of the oil pan - of course.

Joe K
 
Joe K said:
Closer to 0.002 than 0.001.

(heh - 0.0175)

Joe K
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0.0175 would be 17 and one half thousandth. or a little over 1/64

.00175= 1 and 3/4 thousandths. Which is what Herm said.
The rule of thumb is .001 clearnce per inch. crank dia. crank is 1=1/2
so that would be .0015 min like Herm said.
 
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I was told this is a "Sears" engine!!! it was red!! I reshimmed #2 and got close to a .002 with the plasti ( at the bottom of the stroke)--tightened to 42 ft lbs---to tight!! All others loose.. AT WHAT CRANK POSITION SHOULD I ADJUST TO GET A TURNABLE CRANK?
 
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