Amsoil in a 5.7 (~1000hours) or still use T5 ?

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Hello,
I have a Mercruiser 5.7 with around 1000hours in the heart, I always put Rotella T5 15w40, but now the API SM is over.

What do you think switching at 1000hours on full Synthetic AMSOIL 15w40 ? AM I gonna expect some leak problem ?
Should I keep going with T5 even without the API SM ?

thanks
 
My last UOA on my 4Runner with Rotella T4 10w30 in CK-4 spec looks pretty darn similar to the old SM spec. It's boxed and labeled as CJ-4 /SM but in the new bottle and confirmed by shell rep on here that the new bottle contains CK-4 despite the label stating CJ-4 SM. To me that says it would've also met the SM specs but the new labeling requirements force the removal of gas ratings unless the oil companies cut way down on Phosphorus and Zinc. I would continue to use the Rotella with confidence.
 
1000 hours is similar to 60000 miles in a car; several members have switched to synthetic at much higher mileage without issue so IMO you should be fine - and will probably see a cooler running engine and perhaps fuel savings.
 
As an aside with 1,000 hours I'd consider freshening up the top end on your 350. Valve job and new valve springs. They're really ugly when they break a valve spring and end up dropping a valve.
 
The lack of API Sx means nothing, other than the fact that it does not comply with a restriction. Just keep T5 in there.
 
Originally Posted By: JLTD
1000 hours is similar to 60000 miles in a car; several members have switched to synthetic at much higher mileage without issue so IMO you should be fine - and will probably see a cooler running engine and perhaps fuel savings.


I could only dream about driving 60K miles in thousand hours. I seriously doubt I'd see 25K miles in that much time.

Back OT- switching won't be a problem.
 
As others have mentioned, not having the SM spec is meaningless for the engine you’re using. I’d stay the course and keep using it. Switching is also fine, but I’d rather save my money on a motor with that many hours to pay for refreshing exhaust riser gaskets, water pump impellers, stern drive gaskets, and other things that are more likely to ruin your day than the brand of motor oil.

I run Delo 400 LE 15w-40 in my Nautique. Going to try and find a couple more oil changes of older stock, just so it continues to have a steady diet of the same thing it’s had for the last 3 oil changes. But that’s honestly #30 of the things I’m actually worried about with my old boat.
 
Originally Posted By: terminaldegree
Switching is also fine, but I’d rather save my money on a motor with that many hours to pay for refreshing exhaust riser gaskets, water pump impellers, stern drive gaskets, and other things that are more likely to ruin your day than the brand of motor oil.


Agreed.

It's probably time to do a THOROUGH inspection of the entire drive system.
 
Originally Posted By: Linctex
Originally Posted By: terminaldegree
Switching is also fine, but I’d rather save my money on a motor with that many hours to pay for refreshing exhaust riser gaskets, water pump impellers, stern drive gaskets, and other things that are more likely to ruin your day than the brand of motor oil.


Agreed.

It's probably time to do a THOROUGH inspection of the entire drive system.


If he's gone 1000 hours without doing that at least once a year, he's probably already on the cusp of apocalypse.

Unless you have a catalyzed 5.7 (doubt it), your engine isn't going to care that SM was dropped from the bottle.

Where the engine is concerned, skip the top-end job. A brand new crate engine + brass freeze plugs is less than $2000. When that top-end is done, kick the whole engine, rather than tighten the top, just to start having bottom issues.

When dealing with big blocks at $5,000+ for a crate, we bother with the top end (especially since big blocks love to get a hole ate through their heads). On a 5.7? We'll do it if someone is adamant, but pretty much nobody ever has been.

Amsoil in that engine? See above. Every oil change, throw your savings by using T5 into a jar marked "crate engine". Might be surprised how much of the job your jar will cover when the time comes.

Use some nice RA or WM dollar clearance filters, and jar that savings too.
 
Originally Posted By: JLTD
1000 hours is similar to 60000 miles in a car; several members have switched to synthetic at much higher mileage without issue so IMO you should be fine - and will probably see a cooler running engine and perhaps fuel savings.


Maybe if you floor it at every takeoff and run it at 3000RPM when cruising. Boat engines live a way harder life than a car engine. I'd say 1000 hours is closer to 120-150,000 miles.
 
Originally Posted By: Yannick
Hello,
I have a Mercruiser 5.7 with around 1000hours in the heart, I always put Rotella T5 15w40, but now the API SM is over.

What do you think switching at 1000hours on full Synthetic AMSOIL 15w40 ? AM I gonna expect some leak problem ?
Should I keep going with T5 even without the API SM ?

thanks


Just curious. Do they put cats on the inboards?
 
Originally Posted By: Snagglefoot
Originally Posted By: Yannick
Hello,
I have a Mercruiser 5.7 with around 1000hours in the heart, I always put Rotella T5 15w40, but now the API SM is over.

What do you think switching at 1000hours on full Synthetic AMSOIL 15w40 ? AM I gonna expect some leak problem ?
Should I keep going with T5 even without the API SM ?

thanks


Just curious. Do they put cats on the inboards?



They do on the most recent ones, and yes, they do use a special oil just for catalyzed engines.
 
Maybe if you floor it at every takeoff and run it at 3000RPM when cruising. Boat engines live a way harder life than a car engine. I'd say 1000 hours is closer to 120-150,000 miles.[/quote]

Just reading this interesting ski boat thread! I had a 351 in my first 1990 ski nautique. I used esso xd-30 synthetic as per the advise from people here. That was over a decade ago lol. In 2010 I bought a 2004 ski nautique with 250 hrs on the GM PCM EX330 Excalibur 350, it now has over 600 hrs.
It has only ever had t4 15-40 in it and it runs strong.

As far as use it probably gets run through the slalom course about a thousand times per year at 32mph which is about 3200rpm. When pulling a skier up on one ski we usually go full throttle for a couple of seconds before pulling back and letting the cruise control take over for the slalom course. So In response to the member above who was guessing at what boat hours look like in miles I would think that a slalom course tool like a nautique or Mastercraft is seeing some "harder" miles than not. I change my oil and transmission fluid once a year which is about 30 hrs. I am lucky to be in a group of skiers who all own their own inboards. Anyway happy skiing!
 
I understand the OP concern,
I doubt it would matter, if he wanted to stick to Rotella he can use the Conv T-4, Semi T-5 or Full Synthetic T-6 in the 15/40

Personally if I was him I would go with the Full Synthetic T- 6 15/40 and not think much more about it.

For me, I am pretty sure we are going to use Mystik JT8 15/50 but we live in a far warmer climate here then up north.
Its still possible I might go with something like the T6 15/50 or Super Tech 25/40 Marine oil from Walmart.
 
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Most people with pleasure boats are doing 50 to 100 hours a year. Change the oil at normal intervals and non synthetic 15W40 will be fine.

Most boat engine injest water rather than wearing out when they are scrapped.
 
Originally Posted by Donald
Most people with pleasure boats are doing 50 to 100 hours a year. Change the oil at normal intervals and non synthetic 15W40 will be fine.

Most boat engine injest water rather than wearing out when they are scrapped.


Super Tech or Quicksilver 25/40
or
Rotella Synthetic T6 15w40 (more or less it doesnt have to be conventional 15/40 if you want synthetic, you now have options in syn or conv. )
Personally I like conventional if your one to change on time.
 
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