Atomic-4 Lubrication Questions...

Now, realize, I have an A-4 which does not have an oil filter in the loop (not that the filter kits I've read of will filter 100% of the oil flow) and I'm wondering...

Realize that I've done mechanical work on cars-- all right, so we're talking ancient air-cooled volkswagens-- and I've learned a LOT of my skills through the help of John Muir's "How to keep your Volkswagen Alive, Being a Manual of Step-By-Step Procedures for the Compleat Idiot", and there was some discussion about motor oil.

One of the points that was raised had to do with the "ancrient" oil distribution system of the VW engines that had *no* exterior spin-on oil filter (which you find on far more modern engines... and there's a retro-fit kit for the A-4, too) and the discussion of detergent-- and non-detergent-- oils.

In the "non-filtered" system found in the unenhanced A-4 engines (though there's so little HP I'm thinking the word "engine" may be exaggerating matters) wouldn't it be best to AVOID high detergent oils, to keep the grit from circulating?

(I know, it took me a surprising length of time to get to the point, didn't it?)

I almost wish someone had a nice wankel-based powerplant since their size is a lot smaller than an equivalent reciprocating engine...

Honestly, I'd just use a 30 wieght, as called for if my memory is intact, and change it at least once a season. If you do this and operate in normal conditions, I don't think you'll ever have an oil related failure (due to selection/type, that is).

Just my .02 as an A4 lover and prior A4 owner

A4 Lubrication...

Emerald said:

Honestly, I'd just use a 30 wieght, as called for if my memory is intact, and change it at least once a season. If you do this and operate in normal conditions, I don't think you'll ever have an oil related failure (due to selection/type, that is).

Click to expand...

Yes, I understand the SAE 30 -- though, realize, Florida's sailing season, at least on the west coast, is over 12 months long. (All right, so July and August are kind of unpleasant.)

But... Detergent? Non-Detergent?

John Muir said that switching from non-detergent to detergent oils was *bad* unless you tore the engine down and flushed out all of the oil passages, the point being that the detergent oil would suck up the grit and put it all into circulation.

To top that off, the synthetic oils have detergent properties that make regular detergent motor oil look like Oscar Madison even if they're slicker 'n snot.

Wouldn't use a synthetic in an A4. Realize that this is an engine that has roots back, way back, like 20's, and it is all marine, not an adaptation of a Willy etc. (common myth). So, in that sense, oil was basic, and there is a definate case for not breaking it all free if it is just nicely deposited and stable, so no, don't put a detergent in the unknown engine with unknown hours and a filtration system that is just a screen over the oil pump intake.

Substitute 12 months max if your season is longer

As for the power of the A-4. My A-4 will cause the prop to slip at full throttle with the two blade prop. Plenty of power. I figure over twenty of the original thirty horse herd are still alive.

On the A4 bulletin board at moyermarine.com (a treasure trove if you haven't already discovered it) I've gathered the following over the years:
(1) Synthetic oil is not good for Atomic Fours because it results in an extremely low oil pressure
(2) The reason Universal didn't recommend multiweight oil when they built the Atomic Four was because it didn't exist; 10W30 is fine
(3) Detergent vs. nondetergent: nonissue. Change the first detergent oil after a few hours of a hard run if it makes you feel better but it really doesn't matter.

I don't have any interest in debating oil weights, but my personal choice would be to use a 20-50 in the A4 if I went with a multi-weight oil. This is of course assuming summer temps, not cold weather. The reason I'd go 20-50 is just that older engines tend to have looser tolerances, and the heavier oils often maintain better oil pressure.

If you really want to go nuts on this, and have an oil pressure gauge, get a batch of each range say 10-30, straight 30, and 20-50, and start taking notes on what oil and ambient temperature and pressure you run during different points of the engine's operation. Note the pressure running cold right after start and then the pressure after fully warmed up. And remember, you can drive yourself nuts if you over analyze this stuff - just use a good quality oil of reasonable viscosity range and change it regularly

I love the A4

All,

Thirty weight oil and change it when it picks up color change. My topic that I tell all A4 users is drain your manifold after every use and check your exaust every season for build up that kills performance. I brought back my engine from the hell of sitting for seven years in a flooded boat. I am a huge A4 fan and feel it has more power than I will ever need. IMHO.

Good Sailing....