Rotella 15W40

[smosher]

Hi, I changed to the Rotella 15W40 After reading its praise on the forum.
Yesterday I moved my boat from its winter layup to the summer mooring. This
took about 2 hours and several bridges. The engine never sounded better. My sewing machine tic went away and the oil pressure stayed at 40 psi regardless of rpm even at idle after the 2 hour's.

Previous I was using straight 30W.

A big thumbs up for the Rotella

Steve

[Kelly]

Good news. Can you tell us what your performance was like with the previous oils you used?

[hanleyclifford]

A caution

After running the Rotella up and down the coast I can report the only downside is the high oil pressure at start up. Just give the engine a few extra minutes to heat up and drop the oil pressure below 45 psi before applying any big loads.

[smosher]

On the straight 30W, there would be the tappet tic at idle and after running the engine under power for an hour or so, the oil pressure at idle would drop to 20 psi.

Now with the Rotella, the tic is gone and after 2 hours running yesterday the oil pressure at idle was 35 psi. It did drop 5 psi from power to idle. I don't have a tach. I set the throttle to run the P30 5 1/2 - 6 kts.

The engine sounded happy :-), quieter. I ran it for about 60 minutes at power, then idle for 10 minutes waiting for the bridge to open, another 45 minutes, then idle for 20 minutes waiting for the 2nd bridge to open and then a 1/2 hr to the mooring, idle after that.

When I was waiting for the bridges to open I would sneak below to look at the gas pressure as I just converted to electronic fuel pump. I did notice that sometimes the needle would swing wildly at idle. Not sure what that means. I didn't have any problems, but I think I am running a little rich at idle as it will slightly stumble on power up. I didn't have this with the mechanical fp, but that pressure was at 4 psi, while the facet is at 5 psi

Steve

[hanleyclifford]

Wildly swinging pressure readings can be modulated by using a "snubber" available at McMaster-Carr.http://www.mcmaster.com/#pressure-ga...ubbers/=hsd5kb

[JOHN COOKSON]

I didn't have any problems, but I think I am running a little rich at idle as it will slightly stumble on power up. I didn't have this with the mechanical fp, but that pressure was at 4 psi, while the facet is at 5 psi
Steve

When I was a little rich on the idle on my A4 here's what I did to confirm it: After the engine was idling for awhile in neutral for rev it up and "unload" it before putting in gear. If this gets rid of the stumble it is a sure sign of a rich idle.
To confirm a lean idle use a little choke.
BTW a quarter turn on the needle adjustment is all it took to go from a to rich idle to a slightly lean idle.

TRUE GRIT

[CalebD]

Another +1 for Shell Rotella T oil.
When we bought our Tartan 27 about 10 years ago the PO instructed me to only use Rotella oil in the engine. I have stuck to his advice and used the straight 30W oil ever since and the engine seems to like it.
My next oil change will be using Rotella 15W 40 as the auto parts store did not have the 30W in stock.
The only time I used a cheaper non-Rotella oil was when we got water in the engine oil and I had to do 3 separate oil changes before refilling with the good stuff.
Having read the section in Nigel Caulder's "Boatowner's Mechanical & Electrical Manual" on engine oil I learned about the American Petroleum Institutes (API) decal that is on every quart of oil sold in the US. Most oils are intended for use in spark ignition engines and are designated with a 'SJ' or 'Sx' code. The higher the second letter the more sophisticated the additives. Rotella is rated good for both spark and compression ignition engines and there are only a handful of oils that can claim to be good for both gas and diesel engines.

[Crash]

I switched over a few months ago too and she sounded sooo schweet!

[Mo]

A couple of changes to A4 owner in my area
- 15W40 diesel oil
- RWC...by-valve and no t-stat.
- 50/50 mix of auto antifreeze for winterization.

I have about 10 of these babies that I regularly deal with. I personally push this and will help others out free of charge if they try and avoid problems.