John Deere LA145 blowing white & blue smoke

rocky4

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Jul 16, 2014
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I'm working on a John Deere La145 riding mower, B&S 20 Hp, model 407777, Type 0146 B1, code 080923YG, That is blowing white and blue smoke. I have replaced the head gaskets, the valves oil seal and removed flywheel and cleaned the reed valve
( it had some oil in it.) The motor starts just fine and runs realy good but smokes. It did have a bent intake push rod on one
cylinder and the exhaust rocker arm had worked loose and the push rod had dropped down,( this cylinder was not working).
I replaced the intake push rod and made the adjustments on all valves.I did notice when I had the heads off, and engine setting
for a few hours, that there was oil seeping out into the cylinder. Both did this, dont know if that is normal or not.
I did a compresson test which showed 170 lbs on each cylinder. I'm to the point of thinking there is an oil ring problem.
I did replace the fuel pump which made no difference. I removed the tube from the reed valve to the air filter and just let it hang free, started the engine and some oil did come out. That is when I pulled the flywheel and cleaned the reed valve but oil is still comming out there.
Am I to the point of replacing valves or what?
Thanks for any help with this problem
 
D

Deleted member 97405

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My advice would be to do a leak-down test on each cylinder and see where the air is blowing out.
If there is any leakage, the leakdown test will reveal it.
Sometimes those heads will warp and not seal correctly between the cylinder wall and pushrod galley, even with new head gaskets.
Your crankcase will become pressurized and oil will push out past the rings and make is look like you have worn rings.
I have had to replace several heads because of that.
I am assuming you have made sure the oil level isn't overfull.
Hope this helps.
 

rocky4

Active Member
Joined
Jul 16, 2014
Threads
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My advice would be to do a leak-down test on each cylinder and see where the air is blowing out.
If there is any leakage, the leakdown test will reveal it.
Sometimes those heads will warp and not seal correctly between the cylinder wall and pushrod galley, even with new head gaskets.
Your crankcase will become pressurized and oil will push out past the rings and make is look like you have worn rings.
I have had to replace several heads because of that.
I am assuming you have made sure the oil level isn't overfull.
Hope this helps.

Thanks for replying.
The oil level is right on. Is there a way to check if heads are warped without a leak down test?
 
D

Deleted member 97405

Guest
Thanks for replying.
The oil level is right on. Is there a way to check if heads are warped without a leak down test?

Unfortunately, the only way to check the heads is to remove them and lay a straight-edge across them. If you can get access to a leakdown tester, that will eliminate you needing to pull the engine back apart, and it will give you peace of mind that the engine is fine internally. Good luck, and hope this helps.
 

rocky4

Active Member
Joined
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Thanks for replying. Replaced rings and solved the problem. Oil scraper on one cylinder was letting oil pass. All is good now.
Thanks for all the help
 
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