Lean burn question

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700

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If a cylinder is running cooler than another; say it is closer to the water pump and receiving the water from the exchangers first. Does this make it run leaner or fatter than the cylider with hotter coolant around it? or is it just air temp that has effect and the cooler water cylinder actually less suseptible to Lean burn?
 
u can leaner if its coold down first .... the more heat the more u need to run bigger jet to cool down the exhaust temperature
 
I would say that the first cylinder to receive to cool water would tend to run fatter than the other 2, WITH ALL OTHER THINGS EQUAL.
so in theory you could jet that cylinder leaner
 
That have nothing to do with the burning process, and the water will alvays be colder than the engine .. When you start a cold engine, the water is cold. the engine is heating up the water while its sirculating around in the engine untill the thermostat is opening and let the Sirculation go into the cooling system..

I know whats youre thinking, but that is nothing to think about ;) and nobody should try to answer it, because that wil only show that the persons knowledge is missing ;)
 
SRX500_129 said:
That have nothing to do with the burning process, and the water will alvays be colder than the engine .. When you start a cold engine, the water is cold. the engine is heating up the water while its sirculating around in the engine untill the thermostat is opening and let the Sirculation go into the cooling system..

I know whats youre thinking, but that is nothing to think about ;) and nobody should try to answer it, because that wil only show that the persons knowledge is missing ;)
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so funny ....... the warmer it will be the ritcher it will need to be to cool down the exhaust temp..till it start to detonate and then caboummmmm
 
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Sorry, didn't mean to start trouble here. Sounds like there may be some different ideas on this one so we might as well get some more input. Originally I was thinking the other way, had it in my head that the cooler water would act like cooler air temperature and lean out the cylinder but the more I thought about it that didn't make since. :ORC
so lets get some more input on this just for the fun of it; and play nice! :bash:
 
modsrx said:
so funny ....... the warmer it will be the ritcher it will need to be to cool down the exhaust temp..till it start to detonate and then caboummmmm
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okay so you say that the CHOKE should come on when the engine is hot, and not when its cold !? :)
 
If you have a heating problem, then you always should try to upgrade the coolingsytem and then solve the problem, and not think that you can use EGT to manage the problem.. Because is there a problem with it, then you should fix the problem, not try to think that the engine will survive with it! It would not do that..

Guys here in Norway think that EGT solves all kind of problems.. when the alarm goes off, then they sit down and drink coffie untill the engine is cold enough to drive more with.. thats not a good way of tuning a snowmobile..
 
SRX500_129 said:
If you have a heating problem, then you always should try to upgrade the coolingsytem and then solve the problem, and not think that you can use EGT to manage the problem.. Because is there a problem with it, then you should fix the problem, not try to think that the engine will survive with it! It would not do that..

Guys here in Norway think that EGT solves all kind of problems.. when the alarm goes off, then they sit down and drink coffie untill the engine is cold enough to drive more with.. thats not a good way of tuning a snowmobile..
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i agree egt will not fix problem ...but more effecicy the cooling is the better the motor will be on a long pull for heat burn problem....
 
..SNAKEBIT.. said:
I would say that the first cylinder to receive to cool water would tend to run fatter than the other 2, WITH ALL OTHER THINGS EQUAL.
so in theory you could jet that cylinder leaner
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so sorry master!
I thought we was just talking in general, and trying to answer his question
SO IN THEORY! not everything works in the real world
I dont think this guy could be jetting off his water temp?
but maybe he has a water temp sending unit on each cylinder?
 
u doesnt jet for the water temperature ...but more for air fuel ratio... but on a long pull heads create alots of heat so the better the cooling keep the cylinder at the same temp the better it will .... that why the cylinder who run hotter got bigger jet ...cooling cannot cool down cylinder equaly
 
700 said:
If a cylinder is running cooler than another; say it is closer to the water pump and receiving the water from the exchangers first. Does this make it run leaner or fatter than the cylider with hotter coolant around it? or is it just air temp that has effect and the cooler water cylinder actually less suseptible to Lean burn?
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Interesting Question, i thought about it alot and what i have come to is that the hotter cylinder would have to be jetted richer, My reason for thinking that is because fuel is also used to cool the piston(right?) So therefore if a cylinder is running hot the piston will also be running hot so it will need more fuel to cool it, That is what is my thoughts anyway,now on the other hand if an engine is running cool will you be able to jet leaner,i say yes, the piston is running cooler therefore not needing as much fuel to cool the piston. I dont know? i could be wrong,Now this is just an opinion,could be wrong could be right,so i dont need some A HOLE being mister know it all and knocking everybody down, to all their own.
 
crazykid said:
Interesting Question, i thought about it alot and what i have come to is that the hotter cylinder would have to be jetted richer, My reason for thinking that is because fuel is also used to cool the piston(right?) So therefore if a cylinder is running hot the piston will also be running hot so it will need more fuel to cool it, That is what is my thoughts anyway,now on the other hand if an engine is running cool will you be able to jet leaner,i say yes, the piston is running cooler therefore not needing as much fuel to cool the piston. I dont know? i could be wrong,Now this is just an opinion,could be wrong could be right,so i dont need some A HOLE being mister know it all and knocking everybody down, to all their own.
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you go it ;)!
 
modsrx said:
u doesnt jet for the water temperature ...but more for air fuel ratio... but on a long pull heads create alots of heat so the better the cooling keep the cylinder at the same temp the better it will .... that why the cylinder who run hotter got bigger jet ...cooling cannot cool down cylinder equaly
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I agree, the fatter jetting helps to cool the piston etc...
my Master comment was directed to SRX500

PS didnt Yamaha engineers set up sleds for this reason one cylinder needing fatter jetting because of heat? so on the Viper they lowered the compression witch in turn lowered the combustion temp? I guess I should stop before I show everyone what I dont know LOL
 
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SRX500_129 said:
That have nothing to do with the burning process, and the water will alvays be colder than the engine .. When you start a cold engine, the water is cold. the engine is heating up the water while its sirculating around in the engine untill the thermostat is opening and let the Sirculation go into the cooling system..

I know whats youre thinking, but that is nothing to think about ;) and nobody should try to answer it, because that wil only show that the persons knowledge is missing ;)
Click to expand...


Wow, sometimes it's best to keep your comments to yourself so as not to remove all dought.

I can't say as fact that Yamaha has staggered jetting for this reason, but other OEMs have.
 
snomofo said:
Wow, sometimes it's best to keep your comments to yourself so as not to remove all dought.

I can't say as fact that Yamaha has staggered jetting for this reason, but other OEMs have.
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okay so you're the expert here .. najs i follow you!
 
SRX500_129 said:
okay so you're the expert here .. najs i follow you!
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Nope, no expert. Just reponding to your high horse post.

If one cylinder is running a higher temperature than the other two due to higher coolant temps (i.e. last cylinder in the coolant flow to see coolant from the pump - all else being equal), which one will be first to reach the melting point?

Perhaps I didn't understand the original post and if so, I apologize. But I re-read it a couple times and still come to the same conclusion.
 
snomofo said:
Nope, no expert. Just reponding to your high horse post.

If one cylinder is running a higher temperature than the other two due to higher coolant temps (i.e. last cylinder in the coolant flow to see coolant from the pump - all else being equal), which one will be first to reach the melting point?

Perhaps I didn't understand the original post and if so, I apologize. But I re-read it a couple times and still come to the same conclusion.
Click to expand...

EDIT:

I rest my case :)
 
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