Small amount of grey matter in 20 hp lower unit.

[tommr]

I appolige in advance but I did not find an answer in the search.

I have a FD22E 20 hp Johnson outboard and I was changing the lower unit lube.
I pulled the bottom screw and top screw and the lube began to run out.
No free water.
I caught it in a glass jar so I could inspect it.
There was a bit of grey matter, not grainy when rubbed between my fingers.
I would estimate the amount of grey stuff to be about 1/2 teaspoon. The rest of the oil was normal green and there was no grit or gear teeth.

I assume that water is getting into the lower unit. The problem is I had the lower unit apart to replace the prop shaft so it could be any one of the seals. This was a few years ago and every year I replace the oil and I do not remember seeing much grey gunk before.

I am not rich but I do not wish to ruin the motor.

Is there any acceptiable amount of grey stuff or should I just take it apart and replace all the seals.

 

[david_r]

Re: Small amount of grey matter in 20 hp lower unit.

i would think if it were water it would have contaminated all the oil/grease.

was it right with the bottom plug?

did the plug have any on it?......any shavings or whatnot on the plug?

 

[tommr]

Re: Small amount of grey matter in 20 hp lower unit.

This stuff was right at the bottom. Kind of a whitish grey gooby glop. In fact the lube did not flow out until I removed the top plug. But as I said it did not seem to be a lot of stuff. Way less than 1/2 teaspoon.

If was not gritty, smelled bad and tasted worse.

Now that I remember, the original prop shaft was bent. I may have used seals that were new when I inspected the lower unit. It is quite possiable that the shaft seal is leaking.

I wonder if there is a safe way that I can pressure test it with out taking it to the shop. They get $75.00 per hour, fair but more than I can afford.
The shop tech told me that the pressure test is 3 psi for 10 minutes.

Too bad there is no way to adapt one of those coolant system testers to fit the lower unit drain hole.

 

[5150abf]

Re: Small amount of grey matter in 20 hp lower unit.

Change the lower oil and get new seals on the drain plugs then check it again after you use the motor for awhile, if it is milky again you have a seal leaking.

I fish every other week and before a trip I will just crack the bottom plug to check, if there is any water it usually seperates in a couple days and it will come out first.

 

[tommr]

Re: Small amount of grey matter in 20 hp lower unit.

I pulled the lower unit and pressurized it to 15lbs and put it under water.
I took the pump housing off and wiggled the drive shaft 6 ways to Sunday with no bubbles. Same with the shifter. I left it underwater for 6 hours with no loss of pressure.

I replaced the washers on the lube screws and I ran it in the tank with test prop with no apparent leaks.

Maybe it was a bad washer.

Thanks for the help.

 

[jadssh]

Re: Small amount of grey matter in 20 hp lower unit.

Hi All, I was reading this post and just changed my lower unit oil yesterday. I did not change the o-ring on both plugs. Where did you guy's find the o-rings to put on the plugs? Thanks John

 

[david_r]

Re: Small amount of grey matter in 20 hp lower unit.

you can get them here or at your local marine dealer....... i would get the bulk if i was you.

you may get lucky and they may not leak........ but i wouldnt chance it for very long

 

[jadssh]

Re: Small amount of grey matter in 20 hp lower unit.

Thanks for the reply. I will be buying spares on Monday. John

 

[davedepeau]

Re: Small amount of grey matter in 20 hp lower unit.

hey jadssh - i have the same motor, do you happen to know what year it is? thanks

Dave