Help with 1982 Johnson 15 HP - water in bottom cylinder

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Well..in a perfect world.. remember to torque those center ones a little more. Use a torque wrench on the ones you can and duplicate it on the bottom ones with a regular wrench the best you can.

My 76 manual says 12-14 ft-lbs. I have heard 20 also but my 76 says 12-14. 20 sounds better...

You can use a box end wrench with a hanging fish weight scale for a torque wrench. For a 10" wrench..go 12 divided by 10 times the recommended torque.
 
I'll see what I can do with those bolts without removing the Power Head (which I do no know how to do...).


CMOS
 
I tightened up the head bolts as best as I could with no positive results.

I guess it's time for the Head to come off again . . . .


CMOS
 
Time to jump in here again.
It is time for you to pull the powerhead.
These heads do not warp by themselves. Nor do they warp due to any manufacturing defect. There is and never has been any need to stagger the torque of the fasteners to overcome any defect in the many many thousands of these engines produced and still running.
If warped, it was caused by heat.
If you have followed any of my threads on this engine you will know that it is a given that the grommets under the powerhead need to be changed.
Yours has all the tell tale signs of needing this done. Pulling the powerhead is a simple procedure. Fuel line, couple wires, shift linkage if yours is the old stye and around 6 fasteners. Once done you will laugh at how easy it is. Once off you can check the head and install a new gasket. Before pulling, I would check the compression and compare to any numbers you may have taken before.
Are you running in cold water with no thermostat? If so put the thermostat back in before you go this far.
 
Pappy said:
Time to jump in here again.
It is time for you to pull the powerhead.
These heads do not warp by themselves. Nor do they warp due to any manufacturing defect. There is and never has been any need to stagger the torque of the fasteners to overcome any defect in the many many thousands of these engines produced and still running.
If warped, it was caused by heat.
If you have followed any of my threads on this engine you will know that it is a given that the grommets under the powerhead need to be changed.
Yours has all the tell tale signs of needing this done. Pulling the powerhead is a simple procedure. Fuel line, couple wires, shift linkage if yours is the old stye and around 6 fasteners. Once done you will laugh at how easy it is. Once off you can check the head and install a new gasket. Before pulling, I would check the compression and compare to any numbers you may have taken before.
Are you running in cold water with no thermostat? If so put the thermostat back in before you go this far.

Thanks Pappy.

I have to admit I'm nervous about doing this myself, but right now it's a ~75 lb paper weight.

Are you referring to the "shift linkage" down where the lower unit connects?


CMOS
 
timsmcm said:
Do you have a factory service manual? If not get one.


I do indeed.

One thing I have noticed about the service manual - it states in many places to "remove" this or "replace" that, but doesn't detail HOW to do so.


CMOS
 
Sometimes economics dictate technical decisions. I was not insinuating there was anything wrong with the head or the settings that have been in use for many years. 4 fasteners is the norm in higher performance motors in that area instead of 2. Granted I have only mic'ed 4 of these head gaskets and all were thicker in the middle. As long as the job gets done I guess 2 are fine. I don't see the issue with optimizing though..

When you pull the head the problem will be evident. For me surface finish is important at the gaskets fire ring area on the head and block. I betcha the leak is at the block..its harder to get clean and flat so forth. When I had my motor apart I ran the head interface of the block over a surface plate with body paper to flatten this area.
 
First, to give you peace of mind.
Will be a bit more specific on powerhead removal.
There are 6 retaining bolts at the bottom that need to be removed.
Remove the air silencer and choke knob from the carburetor.
Remove the rewind starter. You will need a 3/8-16 nut handy. Unscrew the one bolt and be careful not to allow the spring to come out. Watch the lower cup.....
Tie a loop in the starter rope (pull some out). Once removed put the 3/8-16 nut on the bottom of the bolt to retain the starter assy.
Remove the 3 pan mount nuts. Remove the upper two washers (large and small).
Remove the fuel line from the fuel pump. Replace when the powerhead is off...freshen it up!
Remove any ground wiring from the stop switch and the black/yellow as well.
You will see the throttle gearing. This should come up by itself. Note the position for re-assembly. Clean and lube everything while you have the p'head off.
 
Thanks Pappy.

I've done a carb kit and rebuilt the recoil starter twice (this is what happens when I didn't follow the Service manual instructions...) so taking these things off are easy for me.

However - what are the "3 pan mount nuts"?


CMOS


Pappy said:
First, to give you peace of mind.
Will be a bit more specific on powerhead removal.
There are 6 retaining bolts at the bottom that need to be removed.
Remove the air silencer and choke knob from the carburetor.
Remove the rewind starter. You will need a 3/8-16 nut handy. Unscrew the one bolt and be careful not to allow the spring to come out. Watch the lower cup.....
Tie a loop in the starter rope (pull some out). Once removed put the 3/8-16 nut on the bottom of the bolt to retain the starter assy.
Remove the 3 pan mount nuts. Remove the upper two washers (large and small).
Remove the fuel line from the fuel pump. Replace when the powerhead is off...freshen it up!
Remove any ground wiring from the stop switch and the black/yellow as well.
You will see the throttle gearing. This should come up by itself. Note the position for re-assembly. Clean and lube everything while you have the p'head off.
 
If you remember from removing the starter........
Below the starter is the one forward pan mount. The powerhead actually supports the lower motor pan. You will see the forward one in this location. At the rear on either side are the other two.
There is a bushing that loves to fall out of the center of the rubber mount......be aware as Murphy will carry these to remote locations, never to be found again.
Nice thing about the way this engine was designed is that the pan can now be removed and thoroughly cleaned. The mid-section is now light and can be thoroughly cleaned, all the throttle linkage and gears can be removed, cleaned and lubricated, fuel lines replaced, etc.
When you get done you will have an engine that has now been properly serviced and will or should need nothing for quite a while.
 
Pappy,

"When you get done you will have an engine that has now been properly serviced and will or should need nothing for quite a while."


From your mouth to God's ears.


CMOS :mrgreen:
 

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