Single wt oil in Northern Lights Generator?

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Capt. Rodbone

Senior Member
Joined
Sep 6, 2020
Messages
177
Location
U.S.
Vessel Name
SV Stella Polaris MV Sea Turtle
Vessel Make
1978 VanDine Gaff rigged schooner, 1978 Grand Banks Classic Trawler
We’ve had our GB 42 trawler for three years. We just finished the Great Loop. Not the purpose of the post but guess I’ll share that we are going to sell her. We will look for a smaller trawler probably in the 27 to 32 range. Hadn’t planned to list it here. Hadn’t even thought of it until now but maybe I should. There has been quite a bit of interest just from people that follow “Loopers” and want to see our boat when we are ready to show in a week or two.
I hired out having oil and filters changed on both engines and the generators. I failed to tell the boatyard that the Northern Lights (4,600 hrs), uses Delo Multi-grade. He used Shell Rotella T -30 Wt which is what the twin Ford Lehman’s run. I provided the oil so when quantities left over didn’t add up that’s when I realized. I got out my manual and it clearly notes that either route is okay. I should point out the boat lives in the Southeast US, so the beneficial temperature range with multigrades isn’t a need here.
I haven’t run it yet although they of course ran it briefly. I actually like the simplicity of just one brand/wt. oil. I used both simply because prior owners did.
What thoughts do you folks have on this? I don’t anticipate issues, but want the support of you more experienced mechanical minded. It’s no real problem to switch it back to what it has been used to if that’s best.
 
Personally I won't use use straight weight oil in anything except old Detroits that have very specific oil needs. For just about any other engine there is absolutely no advantage to a straight weight oil over a quality multi grade of suitable weight. These aren't the multi grades of the 1960s, oil has come a long way.

That said, if a 30 weight oil is suitable for the engine in question and you're not starting it in overly cold conditions then I wouldn't expect it to hurt anything.
 
Don’t worry about it. I ran single weight oil in 2 different NL generators for 15 years(?). Periodic oil analysis never indicated any issues.
 
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Just remove it and install correct oil
 
The manual will tell you in a chart. The key is “ambient temperature “ for your cold start when you have been away for a few days with a cold engine room. Professional engineers put that there so you don’t have to guess.
 
I would not worry about it. As to listing the boat, I would list it here as well as AGLCA.
 
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