What Oil Should I Use?

[imported_boatin clan]

Does someone have the current spec for engine oil weight for a 1988 Mercruiser 4.3LX? We typically have several weeks above 100 in the summer and several weeks below freezing in the winter. I do not intend to use the boat over the winter.

Any help would be appreciated.

 

[bruceb58]

Re: What Oil Should I Use?

Here we go again!

 

[imported_boatin clan]

Re: What Oil Should I Use?

Hey bruceb58, you yourself say it best in your signature line. I suppose the threads aren't here for informational purposes and self-enrichment after all. Yep, here we go again!

 

[QC]

Re: What Oil Should I Use?

As I run for cover, this is from the current manual:

Crankcase Oil
To help obtain optimum engine performance and to provide maximum protection, we strongly recommend the
use of Quicksilver 4-Cycle 25W-40 Marine Engine Oil. This oil is a special blend of 25-weight and 40-weight oils
for marine engines. If not available, a good grade, straight weight, detergent automotive oil of correct viscosity,
with an API classification of SH,CF/CF-2, may be used.
In those areas where Quicksilver 4-Cycle 25W-40 Marine Engine Oil or a recommended straight weight oil are
not available, a multi-viscosity 20W-40 or, as a second but less preferable choice, 20W-50, with API service
ratings of SH, CF/CF-2 may be used.
IMPORTANT: The use of non-detergent oils, multi-viscosity oils (other than Quicksilver 25W-40 or a
good quality 20W-40 or 20W-50), synthetic oils, low quality oils or oils that contain solid additives are
specifically not recommended.

 

[imported_boatin clan]

Re: What Oil Should I Use?

Thanks QC for the info, you live in my old stompin' grounds - used to live in Chino before moving up to Apple Valley.

 

[Don S]

Re: What Oil Should I Use?

Hey QC, that's the OLD recommendation from 97, here's the new one. Someone actually posted a link that explained the new FC-W rating of oil, but I can't find it right now, maybe they will post it again, or try a google search.

 

[QC]

Re: What Oil Should I Use?

Thanks Don. Now I have that one. The one I posted came from the on-line 2001-2002 Merc Op guide at Boatfix for Carbed engines. I found this link to an FC-W (Four Cycle - Water) explanation:

FC-W

 

[imported_boatin clan]

Re: What Oil Should I Use?

Thank you Don S. and QC

 

[Scaaty]

Re: What Oil Should I Use?

Ya ever walk down a aisle at an auto parts store, and see rows and rows of (supposedly) different oils, and think that "Madison Ave" aint got a little too involved in this stuff?
Lifes getting a little, just a lttle, too damn over engineered and complicated.........

 

[QC]

Re: What Oil Should I Use?

Yep Scaaty, I do. I am generally not into conspiracy theories and I almost always support OEMs: their product, their design, their recommendations. I also think that the 25W40 was specifically blended to force us to use OEM. I don't believe it for a minute, yet what do I buy? You guessed it, Merc 25W40. The OEM side of my brain is stronger than the sceptic side of my brain . . . Oh well, besides, the black bottle with the Merc logo looks cooler 8)

 

[stevieray]

Re: What Oil Should I Use?

AMEN, brother. And we've been force-fed that crapola thru the mass media since we were just bald-faced boys. "Choices - we NEED more choices!"

 

[bruceb58]

Re: What Oil Should I Use?

OK...I can't help myself so here goes...

Gee...guess who started NMMA? Well..the name should give you a clue...National Marine Manufacturers assosciation. Since Mercury can't force you to use their oil...if they did, by law, they would have to provide it for free...they come up with this "organization" that "certifies" various products. Oil is one of those products.

It is basically a self serving organization aimed to sell their own products.

EDIT: One more thing...If you look at the NMMA FC-W approved oils you find AMSOIL. If that isn't a red flag, I don't know what is!

 

[tommays]

Re: What Oil Should I Use?

In reality the NMMA is working very hard to try and fix the mess that getting your boat serviced correctly has become


There trying to set service standards that would be more like a car dealer and Brunswick (mercury) is less than thrilled as it would start to require ALL there dealers to have qualfied service personal

And i have a 4.3 with 29000 hours at 2000 rpm over a 9 year time on it on plain old GTX changed twice a year

I think the 20 gallon oil tank helps

Tommays

 

[Don S]

Re: What Oil Should I Use?

The man asked a simple question.

"Does someone have the current spec for engine oil weight for a 1988 Mercruiser 4.3LX?"

Hate to tell you this guys, but the current Mercruiser spec for his Mercruiser is the one I posted.

All these other oil comments are personal opinions, (Unless taken from "A website" in which case they are using someone elses opinion) personal thoughts of someone else's concepts, and/or conspiracy theories, and just plain ole oil question paranoia.

Pick an oil you like and change it and the filter once a year and you will be fine.

I just tore an engine down this spring the guy used "What ever was on sale or the cheapest at Walmart"
He lost the engine to bad manifolds and salt water in the cylinders for 2 months.
The rod and main bearings looked like new, it was an 89 Mercruiser 350.

 

[bruceb58]

Re: What Oil Should I Use?

I agree with that.

Pick an oil you like and change it and the filter once a year and you will be fine.

As usual, the thread evolved from the original post.

Don...I am curious...what oil do you use in your boats?

 

[Don S]

Re: What Oil Should I Use?

Don...I am curious...what oil do you use in your boats?

My personal boat, I use 30W Delo 400 Until it's gone (That's another story) Then I will use the 25W40.

Customers boats, Merc 25W40 Non synthetic unless they want synthetic, then we use either the Merc or Volvo synthetic depending on what they have/want.

 

[POINTER94]

Re: What Oil Should I Use?

I have used a straight 30W for years. 3500 hrs. on the 302 without any major repair. It is also consistant with the Seloc Manual recommendation. I have always used dino oil and since the engines I work with are older I am concerned about making some dramatic change to synthetics. I do however use synthetics in the lower units. My mechanic, when I need him, says that the new synths can run up to a 50/50 mixture of oil to water while providing adequate lubrication. I have been very fortunate that my lower units have been just this side of perfect when it comes to seal leaks.

 

[beezee28]

Re: What Oil Should I Use?

I have a 3.0L mercruiser and I used sraight 30W oil as per the owner's manual. So far I have no problem using that category oil. Works fine for me.

 

[johnbo]

Re: What Oil Should I Use?

I use 30W Delo 400 Until it's gone (That's another story)

Don, I'm curious about the statement regarding the Delo. I'm using this as well, is there a concern about the oil, not being able to get the oil, or selling the boat?

Thanks,

johnbo

 

[edwardh1]

Re: What Oil Should I Use?

waldo mart sells the dino Merc quicksilver 25w 40 for $4 a quart.
What does the syn cost?