Standby Generator - Diesel or NG?

[RobJ]

I was refering in general to air cooled gasoline/LPG/LNG engines. Air cooled engines have always burnt more oil than comparable liquid cooled engines and this is perfectly normal.

Fair enought, I thought most were talking about diesels.

 

[RobJ]

Referring to air cooled diesels- Rob sez-

I have no question with a steady load the temp will stabilize. But- assuming there is no temperature controlled air flow system, it seems like there would be a wide variance in what that temp would be, in zero deg weather it would run much cooler than in 100 degree weather, correct?

Don't know how much difference it makes in the real world but I'd opt for liquid cooling if given the choice

Well you got me there, hehe all of my work was in the south. I know these engines run everythere including up north, in mines, etc. I can't even guess about this one.

Air cools have a plave I guess. we sold them in all sorts of apps. Everywhere you might find a LC diesel, we could put in an AC diesel. Not one ever freezed over!! There were cases of overheating, dirt, leaves in the fins, etc. No LC system meant less space for the install to.

Rob

 

[RavensRoost]

If noise is an issue or concern, a liquid cooled unit will be quieter (mechanical noise, not exhaust).

RavensRoost

 

[RobJ]

If noise is an issue or concern, a liquid cooled unit will be quieter (mechanical noise, not exhaust).

RavensRoost

Have you compared? Ya know a 2 cycle water cooled diesel makes more noise than all of them. Ever actually heard a 6-71? 4-71, 2-71, 1-71, 0-71?

Any engine you want quiet is going to be wrapped in a sealed house with insulated walls. And even then you still hear the exhaust over all.

But on a side note, a buddy got one of those extra silent mufflers for his ATV. I must say they do work great, couple times I asked if if was running when it was idling. I think they only keep it quiet from other hunters. A deer can still here those big mud tires running through leaves and over branches. I hear they are working on tire shoes.

 

[Highbeam]

In motorcycle races in the woods we get sound tested before the race with a meter. The events recognize that air cooled bikes are louder and inherently ringier by giving much higher allowed sound levels to air cooled bikes. Along the order of an air cooled bike is allowed to be 102DB vs. water cooled at 96.

My stealthy Honda is always around 87 and I frequently get the smart aleck tester telling me to start it up.... but I have personal issues with loud bikes so I like quiet.

All those cooling fins ringing and the lack of a nice insulating water jacket make them louder. Water cooled engines are less sloppy since clearances can be tighter in a controlled temperature environment. Means more HP per displacement and less blow by to consume oil.

For me though, I prefer the air cooled bikes since I tend to crash and those radiators stick out like a sore thumb. Plus the water cooled bikes have no cooling fans so while at the starting gates or at an obstacle in the field they have been known to puke coolant into the dirt.

 

[RonMar]

For me though, I prefer the air cooled bikes since I tend to crash and those radiators stick out like a sore thumb. Plus the water cooled bikes have no cooling fans so while at the starting gates or at an obstacle in the field they have been known to puke coolant into the dirt.

I added a manually switched 12V box fan strapped across the back side of my old RZ-350 radiator for just that reason. Stop and go traffic and slower backroad travel would overheat the beast. That little fan made a considerable difference in the peak temps under those slow riding conditions.

Hard to beat an air cooled 2 stroke for simplicity and crashworthyness, but you can sure get a lot more sustained power out of the water pumpers

 

[Skyco]

For me though, I prefer the air cooled bikes since I tend to crash and those radiators stick out like a sore thumb. Plus the water cooled bikes have no cooling fans so while at the starting gates or at an obstacle in the field they have been known to puke coolant into the dirt.

You ought to see the radiators on my KDX, both are pretty well bent into a concave shape, but surprisingly don't leak!

 

[Highbeam]

You ought to see the radiators on my KDX, both are pretty well bent into a concave shape, but surprisingly don't leak!

I would call that a "custom" feature to increase aerodynamics. I get a little flak at the events for my old school air cooled bike. But at 400cc and my light weight I have never been limited by bike. The dang thing weighs 300 lbs though, which is double what I weigh!

Sorry for the thread hijack. The relevance is that the engineers are able to create higher cylinder pressures, tighter valve stems, more efficiency, and more power, by controlling the engine temperature precisely through water cooling.

There is no doubt that the water cooled engine is a superior performer in most every way. However, there will always be a place for air cooled engines. Lighter weight, less expensive to make, fewer components to make or fail, and smaller overall size make air cooled engines more ideal for certain situations like portable generators, chainsaws, lawnmowers, and even clumsy old me on my motorcycle.

 

[kenmac]

I kinda wish my ATV was air cooled so, I wouldn,t have to clean the mud out of the radiator after each ride through the mud. I don't think there are too many air cooled ATV'S on the market as they have seemed to be mostly water cooled these days

 

[RobJ]

Along the order of an air cooled bike is allowed to be 102DB vs. water cooled at 96.

All those cooling fins ringing and the lack of a nice insulating water jacket make them louder. Water cooled engines are less sloppy since clearances can be tighter in a controlled temperature environment. Means more HP per displacement and less blow by to consume oil.

96 to 102, i'd say that's pretty close, even by your own admission. and I'm going to guess these are thumpers you are talking about. all you hear on those is the exhaust anyway. You hear the ehaust for a mile, certainly no actual internal engine noise very far away. And that's what we are really talking about, not exhaust noise. But I will admit you make a better case on a high revving motorcycle engine. Anyone who has had one has seen on some models rubber dampers in some of the fins. I've never seen those on a low revving diesel or gas engine.

And still the looser clearances, still wonder where you are getting those? and please, no automotive writers comments. some actual ring clearances, piston to head clearances, and piston to cylinder clearances. The bottom end is the same. And again with the running temps. Didn't I mention that the air diesels I worked on ran at or near a liquid temps. If anything they could run hotter if needed because there is no liquid to boil out. But they each have their places for sure.

And air cooled engines automatically have more blow by? Really? That would be controled by one thing...ring gap(ring and cylinder wear = more ring gap). So if a water cooled is .004 and an air cooled is .005 that's sloppy?