will it do any harm using 5/30 oil in my A-4

[Shrek]

Hi Folks,

Just stopped by Costco today and picked up some 5/30 wt. oil.

Noticed on the survey results from a while back that nobody is using this oil.

I live in Vancouver, Canada and am wondering if it will do anything bad to my great running engine.

Just had some bluish exhaust smoke show up following the use of Seafoam and then MMO for the last few tankfuls of fuel, and now waiting to put in fresh straight fuel and do another oil change. I am hoping the smoke is coming from the crud loosened up by the additives. I have always had some blow-by fumes but this engine starts well and purrs along like a kitten so not thinking anything terminal yet. Possibly worn rings?

Anyway main question is re. this grade of oil.

Many thanks as always - Gordon Foster 1972 Columbia 30 with A-4

[JOHN COOKSON]

From what you described a wet and dry compression test would be good idea.
If the compression is OK you will have some baseline numbers going forward.

ex TRUE GRIT

[ndutton]

To chime in on your oil question, I don't think it's a big issue but keep an eye on your oil pressure. As for the exhaust smoke, there is a good chance it is a byproduct of the additives or at least they're contributing to it. I know with 1% MMO in my fuel I get a wisp of smoke that did not exist prior to using it as a fuel additive.

[joe_db]

I would not use that oil. 5w30 is too thin IMHO and modern car oil has too little zinc and too much anti-friction additives for an old engine. I use Rotella 15w40 oil intended for diesels with good results.

[Shrek]

Best oil to use ?

I heard from an owner that he uses 15/40 rotella and have Also heard that 40 weight oil can clog the oil passages. Can we use 40 weight oil safely in an A4 or should I stick to some other multi grade oil. Would it reduce blow by ?

[jcwright]

You may find this FAQ from Don Moyer helpful. The 'benefit' you are seeking (reduced blowby) differs from the one Don mentions (higher pressure reading), but, as often happens, there are tradeoffs to consider. -Jack

"We prefer straight 30 weight detergent oil in the Atomic 4, simply because the engines are usually used at a constant power setting, and mostly during the warm part of the year (which doesn’t really require a multi-viscosity oil). Later Universal owner’s manuals did list multi-viscosity oils as a suitable substitute to straight viscosity oils, but we can’t find where they ever recommended over a 10-30 weight.

"The downside to using heavier than recommended oil is that (while the pressure might be reassuringly high on the gauge in the cockpit), the head loss in oil pressure between the port where it enters each bearing in the center, to the outside of the bearing, is much greater as oil thickness increases. This means that the outer edges of each bearing (crankshaft and cam) is getting somewhat less than designed oil pressure. – Updated: May 26, 2004"

[Shrek]

Thanks for all the replies but.........

All I really wanted to know was - Can I put 5/30 wt oil in my A4 or should I take it back to the store.

I appreciate all the replies, but I got way more information than I asked for.

I remember hearing that too heavy an oil was bad for the engine and so I have decided to return it and pick up some Rotella 30 weight detergent oil as that seems to be the favourite. Perhaps someone could chime in with a simple yes or no to my latest idea.

Yes I will also be doing all the appropriate compression testing and yes I am almost out of the gas which had the MMO/Sea Foam added to it.

So I am hoping to see a reduction in the faintly blue smoke I have been experiencing.

Was down at the boat yesterday and after turning the fuel supply on and operating the manual primer on my mechanical fuel pump, she fires up immediately and purrs like a kitten and sounds nice and quiet.

She likes to consume oil and has blow-by and I wonder if I might have a stuck exhaust valve. One litre of oil about every 16 hours of running but purrs like a kitten !

Thanks again - Gordon

[ndutton]

My misunderstanding. I thought you already had 5/30 in the engine and it was temporary until the upcoming planned oil change. I did not intend to recommend a steady or prolonged diet of 5/30.

[Shrek]

Thanks for all the replies but.........

Thanks Neil,

Perhaps I was unclear in my original post so no apologies are necessary.

Now that Neil has posted again I am wondering IF it might be a good idea to keep the 5/30 wt. oil and use it to flush out all the crud that might have been loosened up by using the Sea Foam and MMO ? and then go with Rotella 0 / 30wt. as my permanent oil.

BTW Is there any harm in using the Rotella supplied for diesel engines or should I stick with regular Rotella?

I feel like a surgeon about to do a blood transfusion !

Sorry again for any confusion caused earlier.

Gordon

[ndutton]

If I were advising it would be to follow Don's protocol to the letter and avoid freelancing. Extract the old oil with the engine fully warmed up (contaminates in solution, thinner to extract) through the 3/4" NPT pipe plug low on the manifold side with the biggest bore tube your extractor has.

Note that a 12 point 3/4" socket fits the square head of the pipe plug perfectly.

[Shrek]

Thank you Neil

Do you think I can use the 5/30 wt. oil to do a flush before adding the final 30wt oil choice per Don's advice. Which brand do you use ?

Always trusted your knowledge - never gone wrong !

A million thanks !

Gordon. Richmond, BC, Canada.

[ndutton]

Do you think I can use the 5/30 wt. oil to do a flush before adding the final 30wt oil choice per Don's advice. Which brand do you use ?

I wouldn't but if someone digs up such a flush recommendation from MMI I'll defer. Shell Rotella is very popular on the forum (research the forum for the preferred viscosity). As for me, I use NAPA house brand straight 30 wt detergent oil.

Your earlier transfusion metaphor is noted. Oil is the life blood of your precious engine so I would approach these decisions accordingly (the reason for my caution about freelancing). As an indication of how important oil can be I offer my daily driver truck. It is a 2004 Chevy Silverado Z71, 5.3 Vortec engine. I bought it new and have minded the oil changes religiously.

As of the first of this year it has 480,000 miles on the original engine that has never been opened up. It runs like a sewing machine with quiet, smooth power, average 130 miles daily. Yep, oil matters that much.

[joe_db]

FYI - I have a remote oil filter with an oil pressure adjustment located on the filter.
It is a bit trickier to get the pressure set than the original adjuster on the engine. I tried a few different oils and Rotella 15w40 seems to work the best. Once the engine warms up the oil pressure gauge seems like it is welded to 40 from idle to full throttle. When I was out two weekends ago I was glad to not have straight 30 weight oil, that would have made the engine harder to start for sure.

[Dave Neptune]

Shrek, I would stick with the heavier oils as that is what the clearances in the A-4 were designed for. The newer engines using the thinner synthetics, have much tighter tolerances for clearance and require the thinner oil to get into the friction areas and do the oiling.

As far as flushing your fine. If you are flushing out water a tablespoon or two of dish soap in the oil will absorb the water into an emulsion for easier removal. Speeds things up a bit.
For cleaning out accumulated gunk on old engines I have often used a mix of 60% plus of diesel fuel. It really breaks the stuff that has been sitting in the galleys. I usually did this before a teardown though. Just don't put any big loads on the engine.

Dave Neptune

[romantic comedy]

My thinking is that oil packaged for a diesel has additives that are specific to the needs of a diesel. I would choose oil packaged for a gas engine. I wonder if the "high mileage" packaging is any different. I wonder about detergent.

As far as viscosity, I would think that multi viscosity or straight weight should be equivalent at operation temp for the same viscosity. I thought that was the way it was determined. They test the viscosity at operating temp....

Straight weight was recommended because there was no multi viscosity at the time.

The dual weights have a thinner viscosity for start up and the heavier for running at temp. I would think this would be ideal.

I use a multi viscosity but would be fine with a straight weight because I live in Florida. If I was sailing in the cold I would use a multi viscosity.