Leaking crank seal
- Thread starter ghost1
- Start date
This is turning into a head scratcher. I replaced sump/sleave and new seal. I filled it with oil and let it set all day and never leaked a drop. I started and let idle a minute and started leaking oil again from seal. I removed dipstick thinking crankcase pressure may be forcing oil out, dried shaft and still is dripping past rubber part of seal that surrounds crank even when not running. Not sure what else to check.
Last edited:
Yes you have a head scratcher.
I would start doing some measurements and also feel how snug the ID of the seals you are buying fit to the shaft. I was replacing seals sometime back and they were selling me the wrong ID seals. The friction fit was not even snug on the ID. the Od was ok.
On some eq I've purposely measured and selected seals that are thinner and install two where the seal housing allowing for such.
Make sure you are not damaging the lip on the seal when installing.
I use a o-ring pick and lube to make sure the lip don't get damaged.
I've noticed that some replacement seals now days DO NOT HAVE the lip spring inside the seal to assist in holding the lip tighter to the shaft. I keep heads up about such and can most generally save the spring from the old seal and install it into the new seal This is disgusting that they try to save few cents on a spring.
Does the crankshaft have a worn seal groove?
Maybe see if a stainless seal sleeve is available that will fit your crankshaft.
If so be sure to seal the inside of the sleeve. I've seen hot oil leak between the sleeve and the shaft if no gasket type silcon sealant used..
I would start doing some measurements and also feel how snug the ID of the seals you are buying fit to the shaft. I was replacing seals sometime back and they were selling me the wrong ID seals. The friction fit was not even snug on the ID. the Od was ok.
On some eq I've purposely measured and selected seals that are thinner and install two where the seal housing allowing for such.
Make sure you are not damaging the lip on the seal when installing.
I use a o-ring pick and lube to make sure the lip don't get damaged.
I've noticed that some replacement seals now days DO NOT HAVE the lip spring inside the seal to assist in holding the lip tighter to the shaft. I keep heads up about such and can most generally save the spring from the old seal and install it into the new seal This is disgusting that they try to save few cents on a spring.
Does the crankshaft have a worn seal groove?
Maybe see if a stainless seal sleeve is available that will fit your crankshaft.
If so be sure to seal the inside of the sleeve. I've seen hot oil leak between the sleeve and the shaft if no gasket type silcon sealant used..
Also I have seen that spring to get dislodged as the seal was installed. Then the seal works for a while and then start leaking.
I have personally roll a seal lip on a few of these myself; until, I learned to pay extra close attention during installs.
I have personally roll a seal lip on a few of these myself; until, I learned to pay extra close attention during installs.
Need the engine make, model, and spec numbers. Without that info it is only a guessing game as what seal was actually use to start with.
Agree:
That is why I suggested time to start measuring things.
He said he replaced the sump that has new sleeve bearing, so it's time to mic the crankshaft in the area where the seal lip is located. If the crankshaft has a seal wear ring on the crankshaft at the seal area and the crankshaft shaft has too much END PLAY can cause such.
This will require removing the engine and the sump, but NOW THAT YOU REALIZE it leaks with cold oil and the crankshaft not rotating, the issue should not be hard to find the problem.
Just an update. I had spark plugs out to make engine easier to spin and found one of the heads had two cracks on either side of spark plug hole so that slowed things down while I replaced head. After all the grief from crankshaft oil seal leak, I purchased recommended seal from a dealer that carries parts for Generac. The first and other seals were purchased from online market places to save a buck, (I know better). Anyway, when I installed OEM seal it felt like a better fit. Mowed for an hour yesterday and no leaks.