I have been changing the oil in my 78 Lancer with SAE30W oil for years. I walked into a local Sandusky discount Marine store and asked for 30W oil. The gentleman stated that I will destroy my engine if I contiinue using straight 30W oil. His recommendation was synthetic 25W-40. The reason is the EPA has removed all zinc from motor oil which is necessary for flat tappet engines. It's also become difficult to find 30W oil. Where do I go from here? Any ideas?
Valvoline VR1 has 30W with all the goodies you want.
Your store cleark is right about the zinc, it takes abit of researching anymore to make sure the oil you want to use has enough. From what I’ve found you want at least 1,000ppm. If 30W has been working for you I’d continue using that weight, as long as it has the additives you need.
As far as running synthetic oil in old engines, I don’t think it hurts anything. I’ve been switching to synthetic on more and more of my motors, everything I find is that it performs better. My boat motors have been running on Mobile 1 for most of the last 15 years. I ran Rotella T in them for a year then switched back to mobile 1.
I winter store mine with Rotella T4 10W-30 (Zn 1200 ppm) to help with the cold start in the spring - plus it has a high TBN. I switch to the Valvoline VR1 30 wt (about 1500 ppm of Zn) for the hot summer months. Since I change the oil twice a year, I would never realize any benefit from synthetic.
Why do you change twice a year? The 10w30 will be sufficient in summer, the same thermostats are keeping the same engine temps spring or summer. The syn oil is good for many more hours than the dino oil which is good for probably >200 barring fuel dilution etc. I hope you are able to put those hours on the engines therefore need to reward the enjoyment.
Just a bad experience as a child on my dad's boat when an engine through a rod due to multi-viscosity oil break down. I only put about 50 hours a summer on it - but just change it for peace of mind.
Amsoil Diesel has a ton of zinc in it for our older engines. Before I pulled my boat out of the water long term I was Using Amsoil Diesel Full Synthetic 15w-40 on my 48 year old 307Q's and they purred. Never an oil leak either. While most of us never need the extended drain intervals of the Synthetic. It flows so much better than dino oil at startup (when an engine needs it critical points lubricated the most) and offers much better high temp protection in case something happens. But dino oil can work just as well. But my train of thought is if the engines are the heart of your boat and it's basically a big paperweight without them, why not use the absolute best fluid for them....
I was even using Amsoil Torque-Drive Synthetic fluid in my old Paragon P-31s without problems..
Yup.It's the one discussion that will never end. haha
Matt Cowles said:
This discussion has always been funny on any forum I’ve been a part of. They’re always the same...like trying to order one pizza for a party of 15 that includes two vegetarians, a pescatarian, and someone who is gluten free.
Rotella 30 is fine. If you run big dog 427's up your game to 40. And if you run Detroits with Allisons? Same..
I won't debate it. Years and years of Many hours and experience is all I need.
BTW I don't recommend changing from Dino to Syn for one reason. You may start having seals leak. Not guaranteed to happen by it has and I say why risk it? If you really want something to do go into your superdisk and Search "oil" That will keep you busy for a long time!