Which parts of what I said were opinion? I'm confused.
Engine oil or additive propane fueled generator
- Thread starter vatrader01
- Start date
- Status
Originally Posted By: 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.
I did read what you wrote, all of it. You just wrote a whole paragraph about lean and rich and such and it is all opinion and speculation. You don't know anymore about the issue then I do. Show me some documented facts.
In my opinion, I don't buy it.
@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.
I did read what you wrote, all of it. You just wrote a whole paragraph about lean and rich and such and it is all opinion and speculation. You don't know anymore about the issue then I do. Show me some documented facts.
In my opinion, I don't buy it.
Originally Posted By: Oldmoparguy1
Originally Posted By: 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.
I did read what you wrote, all of it. You just wrote a whole paragraph about lean and rich and such and it is all opinion and speculation. You don't know anymore about the issue then I do. Show me some documented facts.
In my opinion, I don't buy it.
Yes, I do not have documented facts.
In fact: I 've never said that this is a FACT. I'm offering my opinions on this.
Argue anyway you want. Afterall: Honda America/Honda Canada never offer any factory propane conversion kits, but aftermarket does. I only deal with propane converted honda generators once in a while, only those on food trucks reap in such high operational hours, and boy! do they need exhaust valve adjustments! On gasoline counterparts: the highest hour ones I've dealt with (EU3000i) clocked about 3.5k and exhaust valve clearances only tighten a thou or 2 and not to the point of backfiring.
I will never be able to take apart that propane converted honda generator until the engine is worn, which, maybe a few more thousands of hours away.
Q.
Originally Posted By: 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.
I did read what you wrote, all of it. You just wrote a whole paragraph about lean and rich and such and it is all opinion and speculation. You don't know anymore about the issue then I do. Show me some documented facts.
In my opinion, I don't buy it.
Yes, I do not have documented facts.
In fact: I 've never said that this is a FACT. I'm offering my opinions on this.
Argue anyway you want. Afterall: Honda America/Honda Canada never offer any factory propane conversion kits, but aftermarket does. I only deal with propane converted honda generators once in a while, only those on food trucks reap in such high operational hours, and boy! do they need exhaust valve adjustments! On gasoline counterparts: the highest hour ones I've dealt with (EU3000i) clocked about 3.5k and exhaust valve clearances only tighten a thou or 2 and not to the point of backfiring.
I will never be able to take apart that propane converted honda generator until the engine is worn, which, maybe a few more thousands of hours away.
Q.
OP, I'd say take a look into that exhaust clearance now. We GS500 riders tend to set the clearance at/above (a tiny bit) the factory recommended interval, and owners report minimal tightening of the valves compared to the already tight end of the factory spec.
Good luck!
Good luck!
http://cdn.powerequipment.honda.com/engines/pdf/manuals/31ZK6601.pdf
Read page 26. Honda does not allow "thin" oils unless the temperature is below freezing on the GX390. They require straight 30.
They also require 50 hour oil changes once broken in.
Read page 26. Honda does not allow "thin" oils unless the temperature is below freezing on the GX390. They require straight 30.
They also require 50 hour oil changes once broken in.
Counterintuitive is a word that crops up when comparing propane/methane fuels to gasoline. Rich/lean temps don't compare to gasoline, and is often backwards on engines running CH4/C3H8. Other words, to a point rich=higher EGTs, lean=lower EGTs. We get used to gasoline characteristics and apply it to other fuels. I don't know the exact mechanism with gaseous vapor fuels that causes EGTs to spike rich of stoich, but have seen it happen personally, and read about it happening to others. SOP on CH4/C3H8 is to set just lean of stoichiometric:
"Opposite of gasoline, set your load block toward the lean side under average load. Your engine is now safe, running clean, and will last longer than it ever could if running on gasoline. Also, there is no need to be extreme about the setting. For alternative fueled engines lean is cooler, cleaner, and most efficient. That’s why if you are camping and traveling and using your generator at different elevations, always reset the load block." (US Carburation)
The coolest illustration of this which I personally witnessed occurred on the dyno of a shop in Houston in the late '80s. Entex, a TX natural gas supplier, wanted to make a replica natural gas powered funny car to use for advertising...."THE POWER" of natural gas etc.
We get there, and know from the noise, something mean is in the cell. One of our party ran inside to check it out while the rest of us are checking/unloading our engines. A minute later he walks out and his eyes are wide, "Guys you gotta see this". Just inside to the right is a big window to the cell and there is this Hemi with a 12-71, and a custom natural gas injection hat on it with headers that are literally white hot. The IR through the glass made it uncomfortable to even face it. Before the next pull I put my sunglasses back on. After about 3 seconds into the pull the headers went incandescent. You could literally see the exhaust pulses, the cool spots, through the header tubes. When there was a miss, you could instantly tell just by looking at it. The pictures/videos of glowing F1 headers pale beside this.
According to one of the employees,it was the second time the engine was on the dyno. First time it melted the headers, and took out $400+ of thermocouples (EGTs). No mention was made of engine damage. Never did find out if those headers were some exotic titanium blend or Inconel.
"Opposite of gasoline, set your load block toward the lean side under average load. Your engine is now safe, running clean, and will last longer than it ever could if running on gasoline. Also, there is no need to be extreme about the setting. For alternative fueled engines lean is cooler, cleaner, and most efficient. That’s why if you are camping and traveling and using your generator at different elevations, always reset the load block." (US Carburation)
The coolest illustration of this which I personally witnessed occurred on the dyno of a shop in Houston in the late '80s. Entex, a TX natural gas supplier, wanted to make a replica natural gas powered funny car to use for advertising...."THE POWER" of natural gas etc.
We get there, and know from the noise, something mean is in the cell. One of our party ran inside to check it out while the rest of us are checking/unloading our engines. A minute later he walks out and his eyes are wide, "Guys you gotta see this". Just inside to the right is a big window to the cell and there is this Hemi with a 12-71, and a custom natural gas injection hat on it with headers that are literally white hot. The IR through the glass made it uncomfortable to even face it. Before the next pull I put my sunglasses back on. After about 3 seconds into the pull the headers went incandescent. You could literally see the exhaust pulses, the cool spots, through the header tubes. When there was a miss, you could instantly tell just by looking at it. The pictures/videos of glowing F1 headers pale beside this.
According to one of the employees,it was the second time the engine was on the dyno. First time it melted the headers, and took out $400+ of thermocouples (EGTs). No mention was made of engine damage. Never did find out if those headers were some exotic titanium blend or Inconel.
Cool story. Sunglasses to look at the exhaust manifold.
Originally Posted By: 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.
Yes....BUT methane enters as a gas in combustion chamber....when gasoline enters as gasoline AND after that sublimate into gas...and with that transformation cools a little combustion chamber...and because engine runs ritcher wit gasoline (14,7:1)...when unburnt gasoline enters into muffler...it sublimates again...and cools down exaust valves
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.
Yes....BUT methane enters as a gas in combustion chamber....when gasoline enters as gasoline AND after that sublimate into gas...and with that transformation cools a little combustion chamber...and because engine runs ritcher wit gasoline (14,7:1)...when unburnt gasoline enters into muffler...it sublimates again...and cools down exaust valves
I bought a used Winco propane generator. The engine had been replaced because of burned valves. They gave me the old engine in a box. The reason they sold it was that the generator head was broken. It's still a project in progress.
The people had used a backup generator as an off the grid generator and had put a lot of hours on it.
The people had used a backup generator as an off the grid generator and had put a lot of hours on it.
Last edited:
Originally Posted By: Kamele0N
Yes....BUT methane enters as a gas in combustion chamber....when gasoline enters as gasoline AND after that sublimate into gas...and with that transformation cools a little combustion chamber...and because engine runs ritcher wit gasoline (14,7:1)...when unburnt gasoline enters into muffler...it sublimates again...and cools down exaust valves
Well I think your terms are a little messed up, there is certainly no sublimation going on in an ICE. I think you mean atomization or vaporization instead. I agree that what passes through the valves with gasoline is on a molecular level droplets of gasoline as opposed to methane. But once it has burned, there's nothing different in the muffler, just carbon dioxide and water in both cases. And in a small engine the water from combustion does not condense as it does in an automobile, the muffler is way too hot. There shouldn't be unburned gasoline entering the muffler I wouldn't think.
I thought it was residual ash on the exhaust valves that kept them from burning? That's why oils formulated for natural gas engines have an ash content around 1%?
Yes....BUT methane enters as a gas in combustion chamber....when gasoline enters as gasoline AND after that sublimate into gas...and with that transformation cools a little combustion chamber...and because engine runs ritcher wit gasoline (14,7:1)...when unburnt gasoline enters into muffler...it sublimates again...and cools down exaust valves
Well I think your terms are a little messed up, there is certainly no sublimation going on in an ICE. I think you mean atomization or vaporization instead. I agree that what passes through the valves with gasoline is on a molecular level droplets of gasoline as opposed to methane. But once it has burned, there's nothing different in the muffler, just carbon dioxide and water in both cases. And in a small engine the water from combustion does not condense as it does in an automobile, the muffler is way too hot. There shouldn't be unburned gasoline entering the muffler I wouldn't think.
I thought it was residual ash on the exhaust valves that kept them from burning? That's why oils formulated for natural gas engines have an ash content around 1%?
Yes...vaporization...
And in muffler there is quite enough unubrnt fuel left...which after vaporization cools down combustion chamber/valves/piston...
Set chainsaw too lean and you will see what I meant...you will get scored piston...because piston will expand too much due excesive heat in combustion chamber...
And in muffler there is quite enough unubrnt fuel left...which after vaporization cools down combustion chamber/valves/piston...
Set chainsaw too lean and you will see what I meant...you will get scored piston...because piston will expand too much due excesive heat in combustion chamber...
Originally Posted By: kschachn
I thought it was residual ash on the exhaust valves that kept them from burning? That's why oils formulated for natural gas engines have an ash content around 1%?
I dont know why there is need for different oils for gas engines...
But for now...what I red is oposite of what you said...
Because gas engines are DI (direct injected)...valves doesent get cleaned by mixing fuel in the chamber...therfore it is vise to use low SAPS oils in gas engines...that there is less ash residue on valves...
But I want to know whole story about "special" oils for gas engines...
I thought it was residual ash on the exhaust valves that kept them from burning? That's why oils formulated for natural gas engines have an ash content around 1%?
I dont know why there is need for different oils for gas engines...
But for now...what I red is oposite of what you said...
Because gas engines are DI (direct injected)...valves doesent get cleaned by mixing fuel in the chamber...therfore it is vise to use low SAPS oils in gas engines...that there is less ash residue on valves...
But I want to know whole story about "special" oils for gas engines...
I have a kohler lightplant runninh lpg fuel and has since it left the factory 60+years ago. It has a drip style oiler installed to drip MMO in the intake. maybe that could be some food for thought.
harvey
harvey
I'd be more worried about the engine getting up to temp long enough to drive the moisture in the crank case out than I would about exhaust valve seat erosion. LPG makes a LOT of water vapor when it's burned and it will condense in the crank case.
- Status
