New to the site with a question about a 1996 90hp Force

[Tcapper]

Hi all, I just purchased boat with a 1996 Force 90HP. I bought it just in time to put it away for the winter. In my haste to move it out of the wife's parking spot in my shop, I forgot to change the bottom end oil. My question is, can I use Lucas 75w90 marine full synthetic oil in place of SAE90 conventional oil. I have found several conflicting statements before joining the forum about not using synthetic oil because of it's lubricating properties. I can't seem to find the answers in any of the other posts. My apologies for the long winded post. Thanks in advance.

 

[Nordin]

In my opinion that synthetic oil will be good enough.
Discussions about which LU oil or two stroke oil is best for your outboard can be a never ending story at internet forums.
Use the gear oil that fits your walet.
I use gear oils 75W90 or 80w90 that are for automotive gears.
The only different between automotive gear oils and marine gear oils that i have figured out is that the marine typ have additives that take care of water if intrusion and another thing is do not use EP typ gear oil for a longer time if the gear case has parts made from red metals. The EP typ of oil will affect the red metals.
Maybe I have start a fire with this answer in this forum.

 

[airshot]

Check the lube container, most will say if approved for marine use. I use the valvoline ( walmart brand) 75-140 full synthetic gear lube for many years with not one issue !! My label states approved for marine use etc. Being a full synthetic oil, the actual weight ( viscosity) is less important because syn lubes don't get thick and thin like dino oils..

 

[Tcapper]

Hey, thanks for the replies, back in the day ('92,'93), I owned a 125 HP U.S. Marine Force when I lived in the Grand Cayman Islands. Always flushed the motor and washed it down after every use due to salt water, zero issues with it. I used Quicksilver oil in the bottom end now I use synthetic in everything I own, just wanted to know if there was any detriment to putting in synthetic, as is I don't know what the previous owner used on this motor. Thanks again.

 

[The Force power]

I use gear oils 75W90 or 80w90 that are for automotive gears.
The only different between automotive gear oils and marine gear oils that i have figured out is that the marine typ have additives that take care of water if intrusion and another thing is do not use EP typ gear oil for a longer time if the gear case has parts made from red metals. The EP typ of oil will affect the red metals.
Maybe I have start a fire with this answer in this forum.

I'm with you on this
Also most automotive gear oil are not anti-foaming VS the marine LU oil

 

[jerryjerry05]

You can use about any oil you decide on.
As long as no water gets in? it should be ok.

 

[Tcapper]

Hey everybody, thanks for the replies. I think I'm gonna grab Merc oil today. Can't take the boat out anyways because of the snow here right now, but at least I can change the oil.

 

[topgun3690]

You can use about any oil you decide on.
As long as no water gets in? it should be ok.

Jerry summed it up pretty well here......if you have water getting in you got a problem that needs repaired......my manual calls for SAE90 so that's what i use, the Quicksilver 90W......and I like the pretty blue color! Lol.

 

[Tcapper]

HeHeHe. Won't be able to tell if there's water in there until I change the oil, but if the bottom end has been taken care of like the rest of the boat and motor, I'm golden. It's funny that the Quicksilver oil is actually more expensive than the Lucas synthetic, at least here anyways. Go figure.

 

[The Force power]

HeHeHe. Won't be able to tell if there's water in there until I change the oil,

IF.....the motor has not ran for a long time; the water mixed-in with the gear-oil WILL separate & sink to the bottom.
So its an easy check to see, Just a word of caution; IF there a high percentage of water in the gear-case it can/will freeze (depending on it's location)

 

[topgun3690]

HeHeHe. Won't be able to tell if there's water in there until I change the oil, but if the bottom end has been taken care of like the rest of the boat and motor, I'm golden. It's funny that the Quicksilver oil is actually more expensive than the Lucas synthetic, at least here anyways. Go figure.

Be sure to replace the Fill/Vent plug washers when changing the lube.

 

[jerryjerry05]

Jerry summed it up pretty well here......if you have water getting in you got a problem that needs repaired......my manual calls for SAE90 so that's what i use, the Quicksilver 90W......and I like the pretty blue color! Lol.

MMMM pretty blue OOOOH.
Saw it in a bunch of colors. 80-140 yellow, Wally World

Had a pair of 88/85hp Forces. They both weeped from the bottom drain plug, NOTHING I did stopped it??? So my lowers were changed at least 5-6 times a year(used the boat a lot)

 

[The Force power]

Be sure to replace the Fill/Vent plug washers when changing the lube. View attachment 391231

I have to in combination with Teflon around the tread, I guess I have same problem as jerry jerry

 

[Tcapper]

Boat was in the water in the summer. Guy needed to sell it before winter. Had some kind of mid life crisis or something and redid the entire boat. The boat was redone from stem to stern, all new flooring and interior converted to movable pedestal seats with bow casting deck , custom made trailer, newer Minn Kota foot controlled trolling motor, new Garmin down imaging fish finders, etc. etc. So he was pretty meticulous about the boat so I'm pretty sure the bottom end doesn't have any issues. As soon as my bottom end oil pump arrives, I'm gonna have at 'er.

 

[The Force power]

Boat was in the water in the summer. He was pretty meticulous about the boat so I'm pretty sure the bottom end doesn't have any issues. As soon as my bottom end oil pump arrives, I'm gonna have at 'er.

Things change over time & he may of overlooked /not been aware of it

 

[Tcapper]

Yup, it's gonna be checked and changed. Then 5 months of looking at it until spring when I can use it.. Man I hate Manitoba winters. LOL.

 

[racerone]

You live there because you like it there.

 

[Tcapper]

I guess I do, besides the occasional minus 40 temperatures. They do call Manitoba the land of 100,000 lakes tho. Lots of fish.

 

[topgun3690]

I have to in combination with Teflon around the tread, I guess I have same problem as jerry jerry

I use yellow teflon tape on my drain plug, it doesn't have a washer or seal, just threads.....

 

[The Force power]

I use yellow teflon tape on my drain plug, it doesn't have a washer or seal, just threads.....

I never seen yellow Teflon-tape for sale here, likely because pipe-dope is to be used here