Moble 1 5W30 Synthetic in B&S Kool Bore Engine

[flatlandtacoma]

Originally Posted By: boraticus
Synthetic oil that is used as though it was mineral oil (short OCIs) is wasteful. Synthetic oil should be used for long enough durations to pay for it's additional cost.

Well I can't recommend extending the interval on an engine that has *no* oil filter. The reason for the frequent changes (e.g. 25 hours) is to get the dirt and [censored] out, not because the oil is worn out.

 

[boraticus]

Originally Posted By: flatlandtacoma
Originally Posted By: boraticus
Synthetic oil that is used as though it was mineral oil (short OCIs) is wasteful. Synthetic oil should be used for long enough durations to pay for it's additional cost.

Well I can't recommend extending the interval on an engine that has *no* oil filter. The reason for the frequent changes (e.g. 25 hours) is to get the dirt and [censored] out, not because the oil is worn out.


All the more reason to do short OCIs using mineral oil. Right? Why use a synthetic to do a mineral oil's job?

By the way, most OPE engines these days recommend 50 to 100 hr. OCIs under normal working conditions.

 

[kcfx4]

running a multi grade full syn can cause consumption of oil, but none the less its consumption of money, most well maintained engines will way outlast the machiene their mounted to (not true commerical)

 

[morrison250r]

Chrome plating on the cylinder. I should have know that. B&S used a aluminum cylinder with a plated piston right?

 

[boraticus]

Originally Posted By: morrison250r
Chrome plating on the cylinder. I should have know that. B&S used a aluminum cylinder with a plated piston right?


I have no idea if it's a plated piston. Construction information isn't easy to come by on these engines.

 

[edhackett]

Most likely not a plated piston. This inexpensive set-up usually is a aluminum piston in an aluminum bore. The block is usually a high silicon content alloy and the bore is "etched" with an acid or other treatment to remove a bit of aluminum, leaving a harder, high Si wear surface.

Ed

 

[boraticus]

I know that a few people were interested in this topic so I thought I'd give an update.

Over the last several weeks, I've burned about a tank and a half of fuel in the snow blower. I've been taking regular oil readings and ensured that the blower was parked in exactly the same place each time. So far, I haven't seen an appreciable drop in the oil level using the Castrol 5W30 High Mileage conventional oil.

However, despite these promising readings, I'm not totally convinced that the oil consumption issue is resolved. The blower has not seen the hours-on-end hard labour that it has in the past. Therefore, I'm thinking that the fairly light duty it's been experiencing may not be taxing the engine enough to put a serious demand on the oil.

We've been getting uncharacteristically frequent but light snowfall this season. Nuisance snow, more or less, so the blower hasn't been tested.

I need a dump of 12" or more of heavy wet snow to give the machine a good work out before I come to any firm conclusions.

When I do, I'll post my findings.

 

[flatlandtacoma]

Could you pull the spark plug and take a quick read?

 

[boraticus]

Originally Posted By: flatlandtacoma
Could you pull the spark plug and take a quick read?


Do you have any Idea how cold it is here? It's -31 with the wind chill. Freaking tools will be sticking to my hands.

But just for you, I'll warm up a ratchet, pull the plug and take a pic.

 

[boraticus]

Originally Posted By: flatlandtacoma
Could you pull the spark plug and take a quick read?


OK.... Thanks to my good old buddy flat-taco, I had to make a trip into town to get a couple new spark plugs. My normally flexible plastic engine cowling wasn't as flexible hence a broken spark plug. Just as well, I don't particularly like Champion plugs.

The business parts of the plug look good. I noticed a bit of oil fouling around the surface of the threaded portion but that could be residual deposits that were on the engine head. This plug had approx. 4-5 hours on it. In my view, not really enough to prove anything one way or the other.

As per your request, here's a pic of the plug:

 

[flatlandtacoma]

Oh man, no I didn't know how cold it was! Well, I don't care for Champions either, maybe I did you a favor?

Is that the original plug from page 1 you cleaned up before the season? It doesn't look too bad. I'm glad the new oil is working out for you!

 

[boraticus]

Originally Posted By: flatlandtacoma
Oh man, no I didn't know how cold it was! Well, I don't care for Champions either, maybe I did you a favor?

Is that the original plug from page 1 you cleaned up before the season? It doesn't look too bad. I'm glad the new oil is working out for you!


Same plug. Just cleaned and gapped it before I put it back in.

Actually, breaking the plug was a good thing. I lost my 3/8" universal joint and as we all know, a 6" extension won't bend much. So I picked up a new universal joint when I bought the plugs.

I bought a couple types of NGK plugs. A pair of BCPR5EGP with narrow platinum tips and one BKR5E with standard tip. I wanted to get at least one hotter plug but these were the hottest they had and I wasn't too keen on freezing my gems off trying to find a hotter plug.

I'm not sold on the idea that the new oil is working. Indicators look good but the machine hasn't seen the extremes that it has in the past. An hour or two moving deep, heavy wet snow will be the test.

So, the new plug is in and I'm waiting for snow. Preferably, lots of snow.

 

[hemitom]

Its to bad the plug broke, now we will never know if the plug was defective or not. I still think that plug was running to cool in that engine causing that oily fouled look. As i stated in a prior post i had a plug that looked identical to that one and it was running to cool in the engine, it was the correct heat range so why , i don't know, possibly defective plug?

 

[boraticus]

Originally Posted By: hemitom
Its to bad the plug broke, now we will never know if the plug was defective or not. I still think that plug was running to cool in that engine causing that oily fouled look. As i stated in a prior post i had a plug that looked identical to that one and it was running to cool in the engine, it was the correct heat range so why , i don't know, possibly defective plug?


Yeah, I hear what you're saying. However, if it does foul, as the old one did, we'll know we probably have an oil problem. If it doesn't, I could switch back to Mobil 1 on the next oil change to see what happens. If there's no fouling with the new plug and synthetic oil, we'll know it was the plug.

 

[hemitom]

Its an experiment in progress, keep us posted.

 

[deeter16317]

Originally Posted By: boraticus
I didn't say that it's burning oil. I said it's consuming oil. The engine is only three years old. It makes plenty of power and runs well. No smoke even on start up. Other than oil consumption, it's a great engine.




Hmmm, sounds like they didn't get the rings lined up correctly...I've seen that cause consumption, but not necessarily burning.

Even with synthetic, it should be through the "break in" period at 75 hours??

 

[boraticus]

Originally Posted By: deeter16317
Originally Posted By: boraticus
I didn't say that it's burning oil. I said it's consuming oil. The engine is only three years old. It makes plenty of power and runs well. No smoke even on start up. Other than oil consumption, it's a great engine.




Hmmm, sounds like they didn't get the rings lined up correctly...I've seen that cause consumption, but not necessarily burning.

Even with synthetic, it should be through the "break in" period at 75 hours??


Rings lined up correctly? I assume you mean the oil ring installed upside down? Could be. I'm not planning to pull it apart to find out though.


The engine is well past break in.

 

[deeter16317]

When the piston is assembled with rings, the rings are obviously not a continuous circle of metal, and have a split/seam or "gap" for assembly onto the piston...you typically have one or two compression rings and the oil control rings, all have the splits.

The splits are supposed to be alternated from side to side of the piston, so they don't line up...but sometimes they get lined up during assembly and that can cause oil consumption issues, similar to that you describe.

And although it seems like the rings would move around the piston, they typically stay where they are installed, or clocked, on the piston.

 

[boraticus]

Originally Posted By: deeter16317
When the piston is assembled with rings, the rings are obviously not a continuous circle of metal, and have a split/seam or "gap" for assembly onto the piston...you typically have one or two compression rings and the oil control rings, all have the splits.

The splits are supposed to be alternated from side to side of the piston, so they don't line up...but sometimes they get lined up during assembly and that can cause oil consumption issues, similar to that you describe.

And although it seems like the rings would move around the piston, they typically stay where they are installed, or clocked, on the piston.


Thanks for that. Could possibly be. As I said, there's no other signs that would indicate that the engine is burning the oil.

On a two cycle engine, there is a small pin in the rign groove with associated indentations on the ends of the ring to line up with the pin. That's to keep the pin from turning within the cylinder. You cannot get the piston in the cylinder if the the rings aren't perfectly fitted.

So, if I read you correctly, the overlapping ring joints are possibly aligned, thus allowing oil to bypass both the oil ring and compression ring? Sounds like a long shot but not impossible I guess.

 

[deeter16317]

Originally Posted By: boraticus

So, if I read you correctly, the overlapping ring joints are possibly aligned, thus allowing oil to bypass both the oil ring and compression ring? Sounds like a long shot but not impossible I guess.



Correct.

Its not a long shot, I've seen it first hand. My grandfather (an automobile mechanic his whole life) had a late 70s/early 80s John Deere garden tractor that used oil from the day he bought it new. I watched him pull the piston on this practically new tractor, show me that the rings splits were all aligned, flip-flop the ring splits to the correct pattern, and reassemble...that was all he did. The tractor quit using oil from that day onward.

As long as the consumption is manageable, I wouldn't worry about it. If the plug fowling becomes an issue, look for a different heat range to help burn off the contaminants.