Logo
FULL SITE MENU

Lower unit woes

R

roncag01

New member
"I had overheating problems wi

"I had overheating problems with an 85 Evinrude 90hp, believe bad water pump to be culprit. When I drained the lower unit oil to drop the lower unit, found it thick and grey.....water mixed in? Could bad water pump be to blame or further problem? Any advice welcome. Thanks."
 
"Your water pump should have n

"Your water pump should have no effect on your lower unit. You said it was thick and grey. With water in it, it should have a milky substance to it and if left for a day or two the water should seperate to the bottom.

If you do have water in there, it many times is just the sealing washers for your drain and vent screws. I would change them first (since it is the easiest) and monitor it closely to determine if water is entering some other way."
 
At 5000 rpm for the driveshaft

At 5000 rpm for the driveshaft the seals do wear out.Have the unit pressure tested or resealed.If maintenance " costs too much " you can not afford the repairs if gears and bearings fail.
 
"Doug, motor has been siting f

"Doug, motor has been siting for a week, when I pulled the bottom plug the oil was grey and thick, when I pulled the top plug, some oil leaked out and was black a much thinner consistancy.

ikia, is pressure testing something I can do?"
 
"Dark color is a lot more norm

"Dark color is a lot more normal than a white milky color. Usually I will remove the bottom drain plug before I remove the upper vent plug. When just the lower plug is out I can usually see if water is in there as it tends to flow out first. A week should have given you the seperation. If you still have the old oil, put it in a glass jar and let it sit (I always do this as well just to be sure). If water is in there it will seperate. If it doesn't then I doubt you have a leak.

I am not entirely sure that water is getting in there. I would change the washer on those two plugs (you should do this everytime anyways) and put in some new oil, and run her for an hour or two and then look at the oil again. Keep that up until you are satisfied that there is either water getting in or not. Keep in mind that right after a run is not the best time to check since any water will be really mixed up well with the oil and harder to detect. Let it sit a day or two, the longer the better before you check it.

A little water for an hour or so run time is not going to ruin the lower unit. It's only when more and more water gets in and therefore less and less oil is available to give you the lubrication, where gear wear starts to happen. The other problem with water getting in is if you let it freeze over the winter, you will have problems so make sure that oil is changed every year at the end of the season no matter what."
 
"I'm a Canadian from Ottaw

"I'm a Canadian from Ottawa, Ontario.

I will pretty much guarantee you that I am not your friend's dad, but I suppose to be sure you would have to send me a picture of his mother first.

Now we are getting way too off topic, so good luck with your motor and if water is getting in, let us know and I am sure we can help you there as well, although it is a lot more difficult if those main seals need to be replaced."
 
"What seals/gaskets should I h

"What seals/gaskets should I have on hand before dropping my lower unit? I will have a whole water pump rebuild kit, but should I change any gaskets for the lower unit?"
 
"I am not familiar enough with

"I am not familiar enough with your motor to advise you on what you need for a water pump repair.

If it were me, I would just do the water pump for now and keep a close eye on the lower unit oil for water intrusion. Alternatively you could have the lower unit pressure and vacuum tested if you want to be sure."
 
Back
Top