Just got me a new 9.8 Tohatsu outboard and the owners man says use 10w30 or 10w40 with a chart for temps and so on, but i can only find 10w30 or 25w40 for outboards here localy. the temp cut off for 10w30 is about 86 deg and here in Tx thats about our low temp. Will the 25w40 be too thick even with this high heat? These little outboards are too pricey to gamble with using the wrong oil other than what the manual says.
New Tohatsu 9.8!
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I'd run the 10-30 without hesitation. As long as you keep the water pump impeller replaced every few years it really shouldn't matter much as the engine has an unlimited supply of stable-temperature water to use.
I'd be worried about starting with the 25w-40, but it really shouldn't be too hard to pull over a 9.8 no matter what oil you choose.
So I think you'd probably be OK either way.
I'd be worried about starting with the 25w-40, but it really shouldn't be too hard to pull over a 9.8 no matter what oil you choose.
So I think you'd probably be OK either way.
Is there something special about outboard motor oil or will standard 10w-40 work?
I don't know the answer to this.
I don't know the answer to this.
A 10w-40 rated for marine service should be more resistant to shearing and have more corrosion inhibitors than an off-the-shelf passenger car oil.
AMSOIL makes a 10w-40 marine oil that will do a fine job.
AMSOIL makes a 10w-40 marine oil that will do a fine job.
Originally Posted By: Rob_Roy
A 10w-40 rated for marine service should be more resistant to shearing and have more corrosion inhibitors than an off-the-shelf passenger car oil.
Agreed. FC-W is the designation for four stroke marine oils:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1271991
A 10w-40 rated for marine service should be more resistant to shearing and have more corrosion inhibitors than an off-the-shelf passenger car oil.
Agreed. FC-W is the designation for four stroke marine oils:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1271991
Just go to a an autoparts store and buy 10w40.
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
Originally Posted By: hattaresguy
Just go to a an autoparts store and buy 10w40.
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
Of course not, and it wasn't my intention to imply that AMSOIL was the only option...it was simply the first FC-W 10w-40 that I thought of. Everyone has different goals and preferences when it comes to choosing an engine oil, so pick whatever works for you.
Just go to a an autoparts store and buy 10w40.
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
Of course not, and it wasn't my intention to imply that AMSOIL was the only option...it was simply the first FC-W 10w-40 that I thought of. Everyone has different goals and preferences when it comes to choosing an engine oil, so pick whatever works for you.
Originally Posted By: hattaresguy
Just go to a an autoparts store and buy 10w40.
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
That's a good point, but at the very least it's important to note the differences between a passenger car 10-40 and a marine oil. A 10hp outboard new runs 1500~2000 dollars. I don't think an extra five bucks a year is a waste especially if this thing runs in salt or brackish water.
As to third world countries I'd be surprised if they run a lot of four stroke outboards.
Just go to a an autoparts store and buy 10w40.
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
That's a good point, but at the very least it's important to note the differences between a passenger car 10-40 and a marine oil. A 10hp outboard new runs 1500~2000 dollars. I don't think an extra five bucks a year is a waste especially if this thing runs in salt or brackish water.
As to third world countries I'd be surprised if they run a lot of four stroke outboards.
Having worked in the marine industry for quite a long time, the whole "boat" oil thing is over hyped. Most 4 stroke outboards I know of run on various types of 10w30 and I have not seen one pop yet.
Oil is oil, marine engines are very easy on it to.
The most important thing you can do to extend the life of a little outboard is to flush it after salt water use. Doing that will do a lot more good than what you put in the crankcase.
Oil is oil, marine engines are very easy on it to.
The most important thing you can do to extend the life of a little outboard is to flush it after salt water use. Doing that will do a lot more good than what you put in the crankcase.
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I may go with the QS Defy 10w40, Its labled as having more zddp.Or would it be best to just use PYB 10w40.
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Originally Posted By: bepperb
Originally Posted By: hattaresguy
Just go to a an autoparts store and buy 10w40.
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
That's a good point, but at the very least it's important to note the differences between a passenger car 10-40 and a marine oil. A 10hp outboard new runs 1500~2000 dollars. I don't think an extra five bucks a year is a waste especially if this thing runs in salt or brackish water.
As to third world countries I'd be surprised if they run a lot of four stroke outboards.
Your right on the cost,($1850 on line) but I am unable to find a 10w40 marine oil,only 25w40.
Originally Posted By: hattaresguy
Just go to a an autoparts store and buy 10w40.
10w40 is 10w40.
Their are thousands of those motors running around in third world countries, think they import Amsoil?
That's a good point, but at the very least it's important to note the differences between a passenger car 10-40 and a marine oil. A 10hp outboard new runs 1500~2000 dollars. I don't think an extra five bucks a year is a waste especially if this thing runs in salt or brackish water.
As to third world countries I'd be surprised if they run a lot of four stroke outboards.
Your right on the cost,($1850 on line) but I am unable to find a 10w40 marine oil,only 25w40.
Originally Posted By: Pablo
Amsoil WCF 10W-40
Amsoil AMO 10W-40
Amsoil XLO 10W-40
I'm up to 9 straight years of Amsoil 4-Stroke Marine (WCF) on my 140HP Suzuki. Love it.
Amsoil WCF 10W-40
Amsoil AMO 10W-40
Amsoil XLO 10W-40
I'm up to 9 straight years of Amsoil 4-Stroke Marine (WCF) on my 140HP Suzuki. Love it.
Originally Posted By: Pablo
Amsoil WCF 10W-40
Amsoil AMO 10W-40
Amsoil XLO 10W-40
Amsoil just isnt for me, but thanks anyway.
Amsoil WCF 10W-40
Amsoil AMO 10W-40
Amsoil XLO 10W-40
Amsoil just isnt for me, but thanks anyway.
Has any one ever used a motorcycle oil in an outboard? I looked at valvoline and there is a 10w40 that has all the correct API certs that are listed as approved oils in the OM.
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