1520 engine question

Over the past few months I have been attempting to rebuild the engine in my 1520 that broke its crank. I took the block and head to a reputable machine shop to get the head rebuilt and check the flatness of the head and block. They also rebuilt the rods and checked the main bearing saddle to see if it needed line bored. I installed the sleeves using liquid soap per instructions. I used plastiguage to check main bearing clearance with the new crank. When I torqued the head on today things seemed to get squirrely. After torqueing the head down the right side of the head gasket seems loose. I can actually move it up and down a little with my finger. After I torqued it down I sat down a minute to let my back pain ease up a little. While sitting there a sharp metallic ping came from the engine. The young man helping me heard it also. After this I tried the torque wrench again and they all tightened a little more. I am pretty sure the gasket shouldn't feel loose like that. I feel lost and almost sick. This is not the first engine I have built but it is my fist deere. Any help/guidance is welcome.
 
Take the head off and check your gasket.
It might be setting on top of the cylinders
instead of down on the edge. (You might
have a 1020 gasket). That noise might have
been the top of the cylinder breaking.
 
Did you check the sleeve stand out height ? They are to be above the block by a certain amount (check book for specs.) and not below at all. Did you get the block counter bores cleaned out really good ? Did you ever figure out why the crank broke ?
 
Thanks guys. I never figured out the broken crank. That's why I had the block checked. I guess I will pull it back apart and start over.
 
Sir, As much as I hate to ask, Where did you place the top packing ring for the liner? I hope you did not have it under the top flange. I have seen this happen before and result breaking the block. I hope this is not the case but, with the head gasket loose it possible you had the packing ring under flange where it did not belong. DW
 
I don't think I did but anything is possible. It has been painfully slow getting time to work on it but I guess I will pull it apart and figure it out . Thanks for your input I don't have thin skin and am not impervious to mistakes. I truly appreciate any suggestions.
 
The others have posted what I would do and that is remove the head and look at the gasket and sleeve.

Now I will add that you need to check the sleeve height out of the block. How you do that is to slide the sleeve into the block WITHOUT the packing rings in the block. Then you measure how far the sleeve sticks above the head surface of the block. The sleeve needs to be .001-.004 above the top of the block. You should use some short bolts in some of the head bolt holes with larger washers to hold the sleeve tight against the block. If the sleeves are too high then remove the sleeve and make sure you have the block clean where block counter bore is. IF it is too low then check and see if your other sleeves are taller. Switch them around to get them all to a positive protrusion. I have gotten bad sleeves that where machined wrong.

To measure how high the sleeve is to the block you can do it several ways. 1) If you have a dial indicator with a magnetic mount you can use it to measure the protrusion. 2) Take a straight edge and hold it flat across the top of the sleeve and measure how far it is above the block with a feeler gauge.

As for the "PING" I would bet that you had a sleeve sticking out too far. Either from dirt or just not installed far enough. The "PING" could have been it just seating into the block counter bore. ( I hope this is true for you) The other things that can happen are that you broke a sleeve flange or worst case the counter bore in the block.


After you installed the sleeves did you clamp them down while you installed the pistons??? If you turned the motor over without the sleeves held down, with the pistons installed, the sleeves will move out of the block when the piston raises in the bore.

P.S. Check how the compression ring sets on top of the sleeve. I have had issues with after market kits not matching. Meaning the compression ring is smaller than the land on the sleeve. That will make the gasket be lose and can break the sleeve flange.
 
Thanks so much J D Seller! You have given me a method to check things that I didn't find in the books. I did not clamp the sleeves while installing pistons so that may be where I messed up. Hopefully I haven't ruined my block.
 

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