Engine oil or additive propane fueled generator

[vatrader01]

Hello. New guy with questions. I have a 10HP Briggs engine powering a 5000 watt Gen-Pro generator. The engine is fueled by propane. I'm wondering if it would extend the life of the engine to use a particular engine oil or an additive to make up for the lack of lubrication that would come from a wet fuel like gasoline. We didn't cover top end lubrication on four stroke engines following a propane conversion in the public schools or the Universities I attended.

Any insights would be appreciated.

 

[kschachn]

Gasoline is not a lubricant and besides, what would it be lubricating if it were?

"Upper cylinder lubrication" as in a "UCL additive" is a joke, there's nothing in the "upper cylinder" that isn't already being lubricated by the oil.

Originally Posted By: vatrader01
Hello. New guy with questions. I have a 10HP Briggs engine powering a 5000 watt Gen-Pro generator. The engine is fueled by propane. I'm wondering if it would extend the life of the engine to use a particular engine oil or an additive to make up for the lack of lubrication that would come from a wet fuel like gasoline. We didn't cover top end lubrication on four stroke engines following a propane conversion in the public schools or the Universities I attended.

Any insights would be appreciated.

 

[Quest]

If your B&S engined generator is manufactured specifically for propane use, then by all means: use it like it should.

If your generator is done by means of aftermarket propane conversion (not by the engine manufacturer itself), then watch out for valve seat recession (esp. in exhaust side).

No such thing called an oil additive that would help ease valve seat recession. Afterall: oil and fuel (inside combustion chamber) don't meet inside the combustion chamber (if it does: you have oil burning problem).

Q.

 

[cat843]

I do believe that propane engines are harder than gas engines on the valves. But if its a backup that should not be an issue due to limited use.

Off the grid I would use diesel.

 

[kschachn]

OK, look at it this way. Even if you were dead set on the need for a UCL, what are you going to add it to? The propane? Because if you're adding it to the oil....

If you really think about your question it makes no sense. You're claiming that oil diluted with fuel is a better lubricant than oil without fuel

 

[CT8]

A propane fueled engine will out last the same engine running gasoline because it is a dry gas.

 

[CT8]

Originally Posted By: Quest
If your B&S engined generator is manufactured specifically for propane use, then by all means: use it like it should.

If your generator is done by means of aftermarket propane conversion (not by the engine manufacturer itself), then watch out for valve seat recession (esp. in exhaust side).

No such thing called an oil additive that would help ease valve seat recession. Afterall: oil and fuel (inside combustion chamber) don't meet inside the combustion chamber (if it does: you have oil burning problem).

Q.
With unleaded gasoline being used all these years hardened valve seats would seem to be mandatory.

 

[Quest]

Originally Posted By: CT8
With unleaded gasoline being used all these years hardened valve seats would seem to be mandatory. [/quote]

Not really: because of the higher temperature when running LPG or propane, even hardened (stellite) valve seats and/or valves used on unleaded engines will erode, oftentimes quicker than what you would like to believe in.

REcently: we've dealt with a Honda EU3000 series engine with propane conversion kit, where after around 2k hrs of run time, the exhaust valve eroded and in need of adjustments (in order to get it running).

Mind you though: these engines are for unleaded gasoline.

consider yourself warned (about valve erosion/valve seat recession when running propane).

Q.

 

[HerrStig]

Rotella T6. Easy winter starts, and does not thin quickly in summer heat.

 

[cat843]

Originally Posted By: Quest
Originally Posted By: CT8
With unleaded gasoline being used all these years hardened valve seats would seem to be mandatory.


Not really: because of the higher temperature when running LPG or propane, even hardened (stellite) valve seats and/or valves used on unleaded engines will erode, oftentimes quicker than what you would like to believe in.

REcently: we've dealt with a Honda EU3000 series engine with propane conversion kit, where after around 2k hrs of run time, the exhaust valve eroded and in need of adjustments (in order to get it running).

Mind you though: these engines are for unleaded gasoline.

consider yourself warned (about valve erosion/valve seat recession when running propane).

Q. [/quote]

Can the valves on small generator engines (20 HP) be machined?

 

[Quest]

Originally Posted By: cat843

Can the valves on small generator engines (20 HP) be machined?


depending on the design: sometimes, if valve seat in block type (flathead configuration), you may have to machine it on-block, or use manual hand valve seat grinding tool, or similar.

For those like ohv type, you can simply replace the head (already came with valve seats installed) and save.

Q.

 

[CT8]

Originally Posted By: cat843
Originally Posted By: Quest
Originally Posted By: CT8
With unleaded gasoline being used all these years hardened valve seats would seem to be mandatory.


Not really: because of the higher temperature when running LPG or propane, even hardened (stellite) valve seats and/or valves used on unleaded engines will erode, oftentimes quicker than what you would like to believe in.

REcently: we've dealt with a Honda EU3000 series engine with propane conversion kit, where after around 2k hrs of run time, the exhaust valve eroded and in need of adjustments (in order to get it running).

Mind you though: these engines are for unleaded gasoline.

consider yourself warned (about valve erosion/valve seat recession when running propane).

Q.


Can the valves on small generator engines (20 HP) be machined? [/quote]

 

[CT8]

Originally Posted By: Quest
Originally Posted By: CT8
With unleaded gasoline being used all these years hardened valve seats would seem to be mandatory.


Not really: because of the higher temperature when running LPG or propane, even hardened (stellite) valve seats and/or valves used on unleaded engines will erode, oftentimes quicker than what you would like to believe in.

REcently: we've dealt with a Honda EU3000 series engine with propane conversion kit, where after around 2k hrs of run time, the exhaust valve eroded and in need of adjustments (in order to get it running).

Mind you though: these engines are for unleaded gasoline.

consider yourself warned (about valve erosion/valve seat recession when running propane).

Q. [/quote]I worked on propane engines for 23 years. 2000 hours and the valve needing adjustment???

 

[vatrader01]

Originally Posted By: kschachn
OK, look at it this way. Even if you were dead set on the need for a UCL, what are you going to add it to? The propane? Because if you're adding it to the oil....

If you really think about your question it makes no sense. You're claiming that oil diluted with fuel is a better lubricant than oil without fuel

I'm not claiming anything. I am stating a concern about using a drier fuel and the premature wear using a drier fuel may cause. The wear may be inevitable. I may, by asking questions on a forum frequented by those that "know", learn that an additive might prolong the life of this investment. Or not.

 

[vatrader01]

Thanks for the responses and discussion. I called the manufacturer [Gillette Manufacturing] and asked if the engine was factory prepped for propane....it wasn't. I may have to accept that this engine has a 1000-1200 hour life span before rebuilding the top end.

I'll also disclose that I use a lot of Marvel Mystery Oil in my small engines. No empirical evidence it helps, however, for over 50 years, I've been around engines that were treated with MMO, and they seemed to last a long time. These engines were well maintained in all other respects, so it is hard to know what affect the MMO really has had....

I usually do my due diligence research before I leap at a purchase. I went with propane to offset the possibility of phase separation / carb contamination common from using today's gasoline / ethanol blends. I didn't consider the valve train wear from the drier fuel.

 

[kschachn]

Originally Posted By: vatrader01
I'm not claiming anything. I am stating a concern about using a drier fuel and the premature wear using a drier fuel may cause. The wear may be inevitable. I may, by asking questions on a forum frequented by those that "know", learn that an additive might prolong the life of this investment. Or not.


OK, you asked if there was an additive for the oil that would make up for the lubrication due to the fuel:

Quote:
I'm wondering if it would extend the life of the engine to use a particular engine oil or an additive to make up for the lack of lubrication that would come from a wet fuel like gasoline.


The fuel does not lubricate, the oil does. As a result there is no additive for the oil that would replace "fuel lubrication" since you would be adding it to the oil, not the fuel. It's a non-sequitur, if you had asked if there was something you could add to the propane that would be different.

The oil is still going to the places that the oil goes to, no more and no less.

 

[Oldmoparguy1]

Originally Posted By: Quest

With unleaded gasoline being used all these years hardened valve seats would seem to be mandatory.
Quote:


Not really: because of the higher temperature when running LPG or propane, even hardened (stellite) valve seats and/or valves used on unleaded engines will erode, oftentimes quicker than what you would like to believe in.
.
Q.


higher temperature with LPG or propane?? I don't see how. Combustion temperature is a function of compression ratio and BTU of the fuel. propane has lower heat content then gas and does burn cooler then gas.

I only have limited experience with dry gas engines, but I just don't buy it.

 

[Quest]

@moparguy:

Please read carefully RE: my posting. It's a propane conversion kit.

2ndly: as opposed to running regular unleaded gasoline (via carb), which typically runs "richer" (lower than 14.7:1) and "richer" mixture tends to run/burn a bit cooler, my suspicion is that comparatively speaking: these so-called "propane conversion kit" tends to run leaner/hotter than that of the gasoline/carb mixture. With that in mind: I would not be at all surprised of the high combustion/exhaust gas temp would have attributed to accelerated exhaust valve erosion (which we ended up having to re-adjust the valve clearance in order to get the issue resolved).

My preliminary conclusion that such conversion kit would have contribute to the exhaust valve erosion, given all other things being equal.

 

[kschachn]

Originally Posted By: vatrader01
I'm wondering if it would extend the life of the engine to use a particular engine oil or an additive to make up for the lack of lubrication that would come from a wet fuel like gasoline.

Originally Posted By: CT8
A propane fueled engine will out last the same engine running gasoline because it is a dry gas.


What do you guys mean by "wet" and "dry"? Both methane and gasoline are a gas at this point, it's not as if liquid gasoline is flowing through the valves into the combustion chamber.

 

[vatrader01]

Originally Posted By: kschachn
Originally Posted By: vatrader01
I'm not claiming anything. I am stating a concern about using a drier fuel and the premature wear using a drier fuel may cause. The wear may be inevitable. I may, by asking questions on a forum frequented by those that "know", learn that an additive might prolong the life of this investment. Or not.


OK, you asked if there was an additive for the oil that would make up for the lubrication due to the fuel:

Quote:
I'm wondering if it would extend the life of the engine to use a particular engine oil or an additive to make up for the lack of lubrication that would come from a wet fuel like gasoline.


The fuel does not lubricate, the oil does. As a result there is no additive for the oil that would replace "fuel lubrication" since you would be adding it to the oil, not the fuel. It's a non-sequitur, if you had asked if there was something you could add to the propane that would be different.

The oil is still going to the places that the oil goes to, no more and no less.


You forgot to ad "In My Opinion".