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

[boraticus]

This morning, I did some maintenance on my Simplicity snow thrower with the B&S 305cc Kool Bore engine. This engine has had annual oil changes using nothing but Mobile 1 5W30 synthetic from new.

When I pulled the spark plug, I was surprised with the amount of carbon/oil residue that had built up on it. I admit, the plug had not been pulled and cleaned for three seasons. The machine always starts on the first pull, therefore there was no need to suspect that there may be an issue with the plug.

The reason I pulled the plug was due to another participant of this forum who had mentioned that Mobile 1 synthetic had caused a great deal of carbon/oil build up on the exhaust valve of his Kool Bore engine. I pulled the plug to see if there was any indication of same in my engine.

I have mentioned in a few posts that my B&S engine has been consuming oil at a rather high rate. There would be a noticeable drop in oil level after a couple hours of moderate use. This is the first and only OPE engine that I have run synthetic oil in. With the realization of oil loss and the other participants report of his experience, I had already decided to switch from synthetic back to conventional oil. Accordingly, I changed to conventional Castrol high mileage 5W30. I'll be keeping an eye on the oil level to see if the Castrol oil is more suitable for this type of engine.

I own and operate numerous two cycle engines. I have NEVER pulled a plug as dirty as this in any of them in decades of use.

Another point of interest was that the top of the piston was very clean. It's pretty much bare aluminum with no carbon build up and just a touch of brown discolouration toward the exhaust valve side. Here's a pic of the spark plug.

 

[bepperb]

Sounds like too cold a plug, if the piston tops are clean.

 

[Jim_Beverlin]

Interesting. I know that Generac which I believe uses the Vanguard series engines from B&S recommends Mobil 1 5W30. I use M1 5W30 in several B&S Inteks that I have along with an unknown series for a pressure washer w/o any issues. Also use M1 in several Tecumshes that power snow blowers. No issues to date. The plugs are clean on the Inteks.

 

[boraticus]

Originally Posted By: bepperb
Sounds like too cold a plug, if the piston tops are clean.



Do you think? It's the recommended plug.

Four strokes aren't like two cycle engines. Spark plug heat range in a four stroke engines isn't anywhere nearly as critical as in a two cycle engine.

Also, in my experience, I've never heard of a spark plug heat range variance causing excessive oil consumption.

 

[boraticus]

Originally Posted By: Jim_Beverlin
Interesting. I know that Generac which I believe uses the Vanguard series engines from B&S recommends Mobil 1 5W30. I use M1 5W30 in several B&S Inteks that I have along with an unknown series for a pressure washer w/o any issues. Also use M1 in several Tecumshes that power snow blowers. No issues to date. The plugs are clean on the Inteks.


Kool bore engines are different that the engines you've mentioned. If it weren't for the advice of the other poster who experienced problems with Mobile 1 synthetic and my engine's excessive oil consumption, I likely wouldn't have suspected a problem. The spark plug however, tells me that I'm probably better off to switch oil.

I'll report how the conventional oil works out after I put a few hours of work on it.

 

[addyguy]

If your engine burns a lot of oil, the plug will get deposits on it - it doesn't really matter if it is synthetic, PCMO, or HSDEO oil used - lots of oil burned equals lots of deposits!

...nice try blaming it on Mobil 1, though!

 

[boraticus]

Originally Posted By: addyguy
If your engine burns a lot of oil, the plug will get deposits on it - it doesn't really matter if it is synthetic, PCMO, or HSDEO oil used - lots of oil burned equals lots of deposits!

...nice try blaming it on Mobil 1, though!


As I had mentioned, I'm not the only person who has experienced negative effects possibly caused by using Mobile 1. It was the other participant who prompted me to be aware that there might be an issue.

I have no conclusive proof that it's Mobile 1 causing the problem. I will know more after putting some hours on the Castrol to see if the engine continues to consume oil. If it does, then it's probably the engine. If not, it's probably the oil.

I've got nothing to gain by bashing Mobile 1. However, if the oil isn't suitable for this type of engine, I think it's only fair to warn others of it's effects.

Stay tuned. We'll know in a month or so.

 

[lexus114]

Originally Posted By: boraticus
Originally Posted By: addyguy
If your engine burns a lot of oil, the plug will get deposits on it - it doesn't really matter if it is synthetic, PCMO, or HSDEO oil used - lots of oil burned equals lots of deposits!

...nice try blaming it on Mobil 1, though!


As I had mentioned, I'm not the only person who has experienced negative effects possibly caused by using Mobile 1. It was the other participant who prompted me to be aware that there might be an issue.

I have no conclusive proof that it's Mobile 1 causing the problem. I will know more after putting some hours on the Castrol to see if the engine continues to consume oil. If it does, then it's probably the engine. If not, it's probably the oil.

I've got nothing to gain by bashing Mobile 1. However, if the oil isn't suitable for this type of engine, I think it's only fair to warn others of it's effects.

Stay tuned. We'll know in a month or so.




Definitely let us know.

 

[tig1]

I have used M1 5-30 or 10-30 in my Honda mower for 20 years with no plug flowing at all. Also a friend is a certified Generic repair tech. and uses nothing but M1 5-30 in all his generators that he does PMs on, and there are many, with no plug flowing at all.

 

[Jim_Beverlin]

I am not familiar with the Kool Bore series so I Googled "Kool Bore series Briggs and Stratton" and it brought up information from an online source that I am familiar with "Jack's Small Engines". Turns out the Kool-Bore on their website was a 5.5 HP OHV Intek Kool-Bore which appears to be indentical to the engine that powers the primary centrifugal pump I use for watering. This motor is probably upwards to 7 years old and has run up to this year on 10W30 M1. I switched to 5W30 M1 since it was recommended for several other Inteks that I have. Using 5W30 M1 did not appear to be a problem but I will pull the plug and check over the weekend and advise back. I did not have to add any oil and the pump probably ran between 30 - 40 hrs this season. I will also check the manual that came with the pump and see if it references if it is a Kool-Bore engine.

 

[MrMeeks]

This engine is worn and requires a higher viscosity oil.
M1 5w-30 is also reported to shear down rapidly to a much thinner
vis.. Try 30wt or a 10w-40

 

[boraticus]

Originally Posted By: MrMeeks
This engine is worn and requires a higher viscosity oil.
M1 5w-30 is also reported to shear down rapidly to a much thinner
vis.. Try 30wt or a 10w-40


Which engine is worn?

If you're talking about this B&S Kool Bore engine, you're mistaken. It's only got three seasons on it at 20 to 25 hours max per season.

The engine is strong, reasonably quiet, easy to start, doesn't smoke and not hard on fuel. It's only fault is oil consumption.

I had two ten h.p. Tecumseh Snow King engines for ten years each on Craftsman snow throwers. These engines were relatively rough running compared to the B&S Kool Bore.

Neither of them were ever lubed with synthetic oil. They both were lubed with any decent quality 10W30 conventional. Neither of them used any oil whatsoever, all season long for the entire time I had them. They ran well and actually outlasted the machines they were on.

This B&S Kool Bore engine either doesn't like synthetic oil or, is simply hard on oil. That's why I've switched oil, to see how it does with conventional.

We'll just have to wait for the results.

 

[tig1]

Originally Posted By: MrMeeks
This engine is worn and requires a higher viscosity oil.
M1 5w-30 is also reported to shear down rapidly to a much thinner
vis.. Try 30wt or a 10w-40


How so.

 

[jdh]

some engines dont like some oils thats all it boils down to, my 22 hp kohler doesnt like kohler or valvoline 10-30 it is always low on the stick after 50 hours where the rotella 10-30 doesnt move from full.

 

[boraticus]

Originally Posted By: jdh
some engines dont like some oils thats all it boils down to, my 22 hp kohler doesnt like kohler or valvoline 10-30 it is always low on the stick after 50 hours where the rotella 10-30 doesnt move from full.


That's my suspicion as well.

Once we get some snow and I put a few hours on the Castrol 5W30, I'll check the oil level to see if the engine consumes it. It went through Mobil 1 at a rate of about half an oz. or a little more per hour.

 

[MolaKule]

Quote:
I did some maintenance on my Simplicity snow thrower with the B&S 305cc Kool Bore engine. This engine has had annual oil changes using nothing but Mobile 1 5W30 synthetic from new.



There's a remote possibility that the engine has never "run-in."

Run your conventional oil for a season and then switch back to synthetic.

Ater run-in, I find that Amsoil's Four Stroke or Mobil 1 5W30 High Mileage works well.

 

[boraticus]

Originally Posted By: MolaKule
Quote:
I did some maintenance on my Simplicity snow thrower with the B&S 305cc Kool Bore engine. This engine has had annual oil changes using nothing but Mobile 1 5W30 synthetic from new.



There's a remote possibility that the engine has never "run-in."

Run your conventional oil for a season and then switch back to synthetic.

Ater run-in, I find that Amsoil's Four Stroke or Mobil 1 5W30 High Mileage works well.



Now that you've brought that up, as per the manual's instructions, I changed the oil at the five hour mark. The oil fill for break in was a conventional 10W30 oil. Thereafter, it's been nothing but Mobil 1.

By the way, when I arrived at the retailer's to pick up the snow thrower, the serviceman was putting Mobil 1 into the engine. He said that the snow thrower had sat in storage for several months and they thought it best to change the oil. I advised the serviceman (a teenager) that synthetic oil shouldn't be used for break in. He advised me that the engines come with synthetic oil in them from the plant. When I got the machine home, I drained the synthetic and replaced it with conventional 10W30 . One would think that if synthetic oil was unsuitable for break in, it wouldn't come with synthetic oil in the engine. Either way, I have no experience with synthetic oil for breaking in engines but do with conventional. Accordingly, I'll continue to use regular oil for that purpose because I know it works.

I use conventional oil in all new engines for the initial 5 hour break in and normally run conventional oil in everything but the snow thrower. This is the first time I've used synthetic oil in an OPE engine. So far, not so good.

Before casting verdict on Mobil 1, I'll wait to see how the conventional oil performs.

 

[flatlandtacoma]

You say you don't see the smoke but I think you're burning the oil. Check the breather, valve guides, head gasket, etc. I doubt it was the Mobil 1's fault.

 

[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.

There is no breather on snow thrower engines. No air filter required due to winter environment conditions. Valve guides are fine otherwise, there would be smoke on start up. Head gasket is fine.

Only time will tell, but I suspect that this type of engine and Mobil 1 are not a good match. We'll see how the new oil does.

 

[flatlandtacoma]

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.


Okay, I know you don't believe you are burning oil, but please show this spark plug to someone you trust (obviously not me):

and ask them if you are burning oil? Hint: You are.

Most people would say you are burning oil, but I guess you can say you are "consuming" oil in the combustion chamber if you like.

Originally Posted By: boraticus
There is no breather on snow thrower engines.


There most certainly is, and when it gets plugged up or ceases to function, guess what happens? Pressure builds up in the crankcase, forcing oil past the rings or the valve guides into the combustion chamber where it is burned, "consumed"

, combusted, whatever.

Thats why I listed breather first, easy to check and a likely culprit. If the breather is fine, maybe you have a bad valve guide or rings. The only other possibility would be a blown head gasket that could build up more pressure than the breather could handle. That's the order I listed them in.

Thousands of people use Mobil 1 in snowblower engines with excellent results. This type of engine and Mobil 1 5w30 are a perfect match. Fix your engine.