Rebuilt engine hard to turn over, but then loosens up?

bertsmobile1

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  • / Rebuilt engine hard to turn over, but then loosens up?
By adding more sump gaskets
The gasket kit should have come with 3 different thicknesses gaskets
 

unioncreek

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  • / Rebuilt engine hard to turn over, but then loosens up?
By adding more sump gaskets
The gasket kit should have come with 3 different thicknesses gaskets
OK thats why there are extra gaskets.

I tried the Dykem and it didn't show anything. Torqued it down to 50 in-lbs, so I could still move it. Turned it about 1/8 of a revolution. I think maybe the crank is too smooth for transfer.

Bob
 

unioncreek

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  • / Rebuilt engine hard to turn over, but then loosens up?
Just one tiny spot, almost like an air bubble popped.
 

shadetree#1

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  • / Rebuilt engine hard to turn over, but then loosens up?
When the end play of the crank is excessive using the thin sump gasket which is usually .015 Briggs mentioned in some of their old service manuals to use a shim kit and shim the flywheel end of the crankshaft.
This is one of the reasons I measure the crank end play BEFORE removing the sump.
Shimming is not mentioned in any of their later service manuals that I have seen.
I make my own shims from shim stock.
One reason that Briggs recommended shimming the flywheel end of the crankshaft is probably? due to a engine's counterbalance clearance at the sump plate. (and on a vertical shaft engine the crankshaft shim being located at the flywheel end is not exposed to the rotating vertical weight of the flywheel/crank weight which reduces the wear factor on the shim)
I'm not saying that this is your issue but I would check such because if the crank has end play the rod is attempting to slide sides ways at the piston and crank.

I'm wondering:???
You indicated in one of your previous posts that you could seize the rod on the crank journal by just torqueing the rod cap, but it appears that now you are indicating the plasti gauge indicates it's ok and the rod does not seize when the cap is torqued to proper specs?????
If this is what you are indicating, WHAT CHANGED the symptoms????
 

Scrubcadet10

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  • / Rebuilt engine hard to turn over, but then loosens up?
When the end play of the crank is excessive using the thin sump gasket which is usually .015 Briggs mentioned in some of their old service manuals to use a shim kit and shim the flywheel end of the crankshaft.
This is one of the reasons I measure the crank end play BEFORE removing the sump.
Shimming is not mentioned in any of their later service manuals that I have seen.
I make my own shims from shim stock.
One reason that Briggs recommended shimming the flywheel end of the crankshaft is probably? due to a engine's counterbalance clearance at the sump plate. (and on a vertical shaft engine the crankshaft shim being located at the flywheel end is not exposed to the rotating vertical weight of the flywheel/crank weight which reduces the wear factor on the shim)
I'm not saying that this is your issue but I would check such because if the crank has end play the rod is attempting to slide sides ways at the piston and crank.

I'm wondering:???
You indicated in one of your previous posts that you could seize the rod on the crank journal by just torqueing the rod cap, but it appears that now you are indicating the plasti gauge indicates it's ok and the rod does not seize when the cap is torqued to proper specs?????
If this is what you are indicating, WHAT CHANGED the symptoms????
he had over torqued them originally
 

unioncreek

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  • / Rebuilt engine hard to turn over, but then loosens up?
They plastigage indicated clearance is 0.0015 on the #1 rod. Still of I torqued rod cap to even 50 in-lbs I can barely move it. At 100 in-lbs I can't move it.

Dykem didn't show any place where is was rubbing.

The new rod should arrive shortly and I go from there then.
 

unioncreek

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  • / Rebuilt engine hard to turn over, but then loosens up?
Received my new connecting rod today. Used the micrometer and snap gauge to check the diameter, it was right at 1.500. Checked it with plastigage and clearance was 0.002". Cleaned up the journal and connecting rod and assembled it on the crankshaft. Torqued it to 100 in-lbs and it turned nice and smooth. I have the engine assembled and will try and make time to install it on the mower and run it. I will keep you posted. That was a cheap enough repair, connecting rod costme $15.00 and $9.00 to ship. Took three days to get here.

Bob
 

Scrubcadet10

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  • / Rebuilt engine hard to turn over, but then loosens up?
good deal. hope it works out for you,
 

unioncreek

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  • / Rebuilt engine hard to turn over, but then loosens up?
Put my engine in my mower this morning. Cranked it for a bit to get the oil in the system. Put the sparkplug wires on and it fired right up. Started it five time throughout the day and it started every time. I'm sure it will start up tomorrow. I'm about a month away from lawn mowing.

How much oil does that engine hold. The manual says 2 quarts, I ended up putting 2 3/4 quarts inthat put it just slightly past the full line.

Bob
 
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