I have a 4.3 merc cruiser fuel injected. do I have to run a marine type oil or can I use castrol edge I have laying around
does marine oil have to be used?
- Thread starter finalyzd
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At least in older motors they recommended straight weight oils. I ran 30 or 40 wt. That was a few years ago, might check your manual for choices.,,
Originally Posted By: finalyzd
I have a 4.3 merc cruiser fuel injected. do I have to run a marine type oil or can I use castrol edge I have laying around
Send me your edge, and I will give you my marine oil I accumulated on clearance when local marine stores went out of business.
But seriously, edge is light duty engine oil for cars (even though capable of extended drains) while marine/Heavy Duty oils have more anti-wear, anti-rust, and detergent additives and more capable for dirty and humid boat service.
Then there is the viscosity difference as mentioned above.
Read similar threads in this very forum.
I have a 4.3 merc cruiser fuel injected. do I have to run a marine type oil or can I use castrol edge I have laying around
Send me your edge, and I will give you my marine oil I accumulated on clearance when local marine stores went out of business.
But seriously, edge is light duty engine oil for cars (even though capable of extended drains) while marine/Heavy Duty oils have more anti-wear, anti-rust, and detergent additives and more capable for dirty and humid boat service.
Then there is the viscosity difference as mentioned above.
Read similar threads in this very forum.
I have always used Rotella 15w40 in my 1975 Mercruiser Blue Water 350HP 454ci(Kiekiefer) since a fresh total rebuild right after purchase in 1991. The +4000lb boat gets WOT runs regularly and many hours of 450rpm putt-putt. It uses no oil 1300 hrs after rebuild. The oil doesn't really get dirty and gets changed once a season or 150 to 250 hrs. Never a problem with the engine. I think I'm on my 6th or 7th starter though. Other unrelated issues. Merc recommends straight 30 or 40wt. I figure these HDEO's are pretty good and always have had the Rotella at my disposal.
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HDEO is what the commercial companies run in their boats in Gas and high speed diesels. The Castrol would be fine as it is a pretty stout oil .
its just at my shop were having a debate. I'm saying to use a hdeo or specific marine type oil. But everyones saying just put edge in or syntec. And I just don't think a regular pcmo would work
Well, that 4.3L is the same GM 4.3L that has been used in trucks and SUVs for years. I'm sure that the Edge would work, but it probably isn't recommended. If I had a boat, personally I'd use a heavier duty oil.
You'll be fine. I've used such a variety of oil in my 3.0LX that you would laugh or loath me. One thing to watch for is the oil pressure guage. See what the pressure is coming off of a WOT run. If it drops dangerously low, you might want to go to a stouter oil. Personally, I use Pennz. LL 15w40 because my boat sits a lot and I like the idea of having a good HDEO oil in ther as I may take it out once every 2-3 years. I'm just really busy right now. Plus, it's paid off and sits in an enclosed garage, so it's not hurting anything.
there is no reason what-so-ever to feel you must run quicksilver or any other "marine" oil, or oil filter for that matter. it could be a volvo but more than likely its a gm made engine. also no reason to run a straight weight nor a HDEO oil. if its gm made, just pretend your buying oil and filter for a s-10 w a 4.3 in it. Edge would be an excellent choice in my opinion, and i doubt your putting alot of hrs on it, i'd say edge and keep it in there all year.
I think you're fine with the Castrol Edge ... for a reasonable interval ... but I don't go so far as kcfx4. Marine oils are formulated similar to HDEOs to deal with fuel dilution and moisture contamination.
I would prefer one to a PCMO for use in a boat any day. The grey area comes when you are talking the really premium synthetics. Will they be able to handle the high-fuel, high moisture conditions? Probably, but ...
I would prefer one to a PCMO for use in a boat any day. The grey area comes when you are talking the really premium synthetics. Will they be able to handle the high-fuel, high moisture conditions? Probably, but ...
Who makes a fully synthetic marine oil? I'm going to have my first I/O here in a week and I'm trying to decide which oil to use.
Bror Jace, i answered accordingly to his question, he was asking about an extended synthetic (edge) not a conventional, he showed no signs to me that even if edge wasnt his choice that he would select a conventional. and indy fan, i believe you can find fully synthetic labeled as quicksilver.
There are some synthetic and synthetic blend marine oils out there ... Amsoil, Sierra, Quicksilver, etc ...
I just had a new 350 put in my boat last year by Michigan Motors. They are recommending 15w40 in all Marine engines so that is what I use. I just put in Rotella T 15-40 for the year. Prior to this, I have always used straight 30 weight. Edge probably wouldn't hurt it but remember, boats are always under a load when running other than idle, they work harder than a car engine IMO.
Originally Posted By: kcfx4
if its gm made, just pretend your buying oil and filter for a s-10 w a 4.3 in it.
When was the last time you ran a carberated S-10 at 4,000 RPMs for 1 hour straight and the engine temp never exceeded 150 degrees? Similar engine, but a completely different application with different demands on the engine and lubrication. Added to the low operating temperatures, these engine are also designed to run rich, which adds to the fuel dilution issue that you will never see in your S-10.
if its gm made, just pretend your buying oil and filter for a s-10 w a 4.3 in it.
When was the last time you ran a carberated S-10 at 4,000 RPMs for 1 hour straight and the engine temp never exceeded 150 degrees? Similar engine, but a completely different application with different demands on the engine and lubrication. Added to the low operating temperatures, these engine are also designed to run rich, which adds to the fuel dilution issue that you will never see in your S-10.
Originally Posted By: medic
Originally Posted By: kcfx4
if its gm made, just pretend your buying oil and filter for a s-10 w a 4.3 in it.
When was the last time you ran a carberated S-10 at 4,000 RPMs for 1 hour straight and the engine temp never exceeded 150 degrees? Similar engine, but a completely different application with different demands on the engine and lubrication. Added to the low operating temperatures, these engine are also designed to run rich, which adds to the fuel dilution issue that you will never see in your S-10.
prehaps true, but i have a 1990 rinker captiva 186, thats obviously 20 yrs old, i average right at 150hrs/yr on a 4.3l v6 gm made engine. it gets a yearly oil change in the spring, it gets an ace ph51a filter from a farm store for $2, and whatever is the cheapest 10w-30 syenthetic i can find, which this yr is Napa full syn that i bought last october for right at $3/quart.....so yes im sticking to my first post...and every year i get ppl w newer boats ask me how my old boat can look/run so well....i keep it in the garage, grease fittings, dump antifreeze down hoses in winter and change oil yearly...heck i put more time/effort into my lawn mower maintence ......oh and i do pull skiers
Originally Posted By: kcfx4
if its gm made, just pretend your buying oil and filter for a s-10 w a 4.3 in it.
When was the last time you ran a carberated S-10 at 4,000 RPMs for 1 hour straight and the engine temp never exceeded 150 degrees? Similar engine, but a completely different application with different demands on the engine and lubrication. Added to the low operating temperatures, these engine are also designed to run rich, which adds to the fuel dilution issue that you will never see in your S-10.
prehaps true, but i have a 1990 rinker captiva 186, thats obviously 20 yrs old, i average right at 150hrs/yr on a 4.3l v6 gm made engine. it gets a yearly oil change in the spring, it gets an ace ph51a filter from a farm store for $2, and whatever is the cheapest 10w-30 syenthetic i can find, which this yr is Napa full syn that i bought last october for right at $3/quart.....so yes im sticking to my first post...and every year i get ppl w newer boats ask me how my old boat can look/run so well....i keep it in the garage, grease fittings, dump antifreeze down hoses in winter and change oil yearly...heck i put more time/effort into my lawn mower maintence ......oh and i do pull skiers
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Originally Posted By: IndyFan
Who makes a fully synthetic marine oil? I'm going to have my first I/O here in a week and I'm trying to decide which oil to use.
Amsoil
Who makes a fully synthetic marine oil? I'm going to have my first I/O here in a week and I'm trying to decide which oil to use.
Amsoil
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