I've recently installed two rebuilds in my fishing boat, 2-GM (Mercruiser) 454 Mk. IV engines. I put in a comp cam, marine specced cam, (still pretty mild, a torquer cam) and slightly heavier springs. Its been 200 hrs, and it should be past break-in. (No cat converters, obviously) I used amsoil 30 wt breakin for the first three fills, then Amsoil HD Diesel and Marine 15W-40 for the last one. So this will be its 5th oil change, Amsoil for these two 7-qt engines is a little more pricey than I need. What is suggested going forward?
OIl for marine engines
- Thread starter srfdude
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Unfortunately none of us PCMO geeks can answer your question. I don't want to be rude but post your question in this forum.
With your little more cam & valve springs it would be a good idea to pick an engine oil with about P1200 & Zn 1300.
In my experience I found that either old school 15W40 or an SAE 30 like Delo 400 kept the cams happy.
By nature, BBCs can be cam eaters. Smallish base circle, 1.72 rocker ratio, .843" lifters and their lifter bore indexing all over the map.
In my experience I found that either old school 15W40 or an SAE 30 like Delo 400 kept the cams happy.
By nature, BBCs can be cam eaters. Smallish base circle, 1.72 rocker ratio, .843" lifters and their lifter bore indexing all over the map.
I would use any of the major brand Chevron, Shell, Mobil etc HDEO oil and change often. The Amsoil you are using will do the job with out breaking a sweat so to say. This would be a great use of a UOA to see how the oil is holding up to see if the Amsoil is worth the cost in regards for the increases oil change interval.. 20w-50 work great in BBC. Why do people buy a boat then want to save money
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The two best days of owning a boat, is the day you buy it and the day you sell it. Every day inbetween a pita.
20w50? Yeah, but mention XW50 anything or SAE 40 and all the thinnies come crawling out of the wood work and from under the carpets.
Most of the new 15w40 CK-4s are P & Zn challenged.
I run VR1 20w-50 in my old Century but will probably switch to my 'go to' of M1 15w-50. Both great oils w/ requisite additive levels. I had an email chat w/ a Mobil tech rep who stated that the 15w-50 would be suitable for the older GM 350.
VR-1 would be my choice. If 20W-50 is too thick?..mix it 50-50 with the 10W-30 version to approximate a 15W-40.
Yep boat = Bring Out Another Thousand
Why would 20W-50 be too thick?
I don’t think it would be..just providing an option for those who think “thinner”..the OP was using 30wt and 15W-40.
Delvac Extreme 15w40 or 10w30
Cheap, Synthetic HDEO with 1400 ppm of ZDDP. 'Nuff said.
Cheap, Synthetic HDEO with 1400 ppm of ZDDP. 'Nuff said.
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Amsoil is cheaper than a seatow
Mobil1 15w50 is easy enough to source.
What does the oil temp and pressure gauges look like when running under load?
Mobil1 15w50 is easy enough to source.
What does the oil temp and pressure gauges look like when running under load?
Yep boat = Bring Out Another Thousand
It amazes me at the comments that the keyboard cowboys interject. Insignificant and an indication of envy. Go enjoy your hobbies. Or do you ride the couch and feel important with statements like those above?
Im open for answers to that question.
HDEO 15W40.
Are you getting Dealer/PC pricing?
AMSOIL 15w-40 is an excellent product. How many hours are you planning on running it?
Mercury 25w-40 syn. blend might be another one for you to consider.
Mercury 25w-40 syn. blend might be another one for you to consider.
I already have the "boat" t-shirt. We are just trying to inject a little humor into the discussion, so don't get your panties in a bunch.
Gunny from Full Metal Jacket would say; "Grow a pair".
VR1 20/50
I assume hydraulic roller cam?
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