Other Anyone adjust seasonally ?

[Mark44]

More fuel = more power right? [/QUOTE]

Not at all.

If you can go up 4 jet sizes you have something horribly wrong in tuning and you need to tune with a tachometer.

Mark44

 

[WFO Speedracer]

i see you got the power back on before GODZILLA attacked.

Yep damn breaker,funny thing is there are two breakers in he box that are not hooked to anything,I need to get to rewiring this thing,whoever did this house did not know WTF they were doing,not that I do but yeah!

 

[WFO Speedracer]

He is correct about the thermostat and controlling temps,not sure about being to go up 4 jet sizes but in theory yes it is possible.Th Polaris watercraft engines used thermostats with a pressure relief valve,out of all the brands I worked on Polaris was less fiddely than the others regarding carb settings,cowinkedink,I think not.

 

[madscientist]

this opens a new can of worms for us to experiment with.

 

[WFO Speedracer]

Jetlyne made a head back in the day for the 650 engine that had a thermostat in it,the main claim besides more compression was consistant tuning or holding a tune.

 

[madscientist]

so by adjusting the cylinder temp it will compensate for having to adjust the carbs for different temps by maintaining a consistent operating temp.

great in theory but how does it adjust for atmospheric changes due to lower air temps?

 

[craven]

I am definitely not trying to sell anyone on this idea, because if I did then the engine rebuilders would go out of business lol. I have been running a thermostat in all of my yamaha's for about 8 years and have not seized an engine since.
You are correct that more fuel doesnt always mean more power, but pre thermostat my engines ran pretty good, I had the pistons showing a slight tan with wash marks at every intake port. I am not arguing if this is your way of tunning or not, it just shows a standard in my machines. Also 1 jet size either way made my boat run ok but less performance. Post thermostat jumped 4 jet sizes and still got the same color pattern on my pistons. 1 jet size either way made little changes. So it wasnt as finiky = less wrenching- more ridding.
Futher more what internal combustion engines have thermostats?
All of them. Your car runs for years , change in temp, change in elevation, little change in performance ( obviously before computers were used is what I am referring to) Jet skis are the only liquid cooled internal combustion engine that doesnt use a thermostat. I am not sure why that is.
Again you can form your own opinion, I am not here to debate tunning, performance, if it is right or wrong. It works for me and I like it.
By the way I also run BR7ES plugs too.
I learned these ideas from an old school engine builder for drag cars, it made sense so I used it. :nutkick:

 

[Rickster]

I am definitely not trying to sell anyone on this idea, because if I did then the engine rebuilders would go out of business lol. I have been running a thermostat in all of my yamaha's for about 8 years and have not seized an engine since.
You are correct that more fuel doesnt always mean more power, but pre thermostat my engines ran pretty good, I had the pistons showing a slight tan with wash marks at every intake port. I am not arguing if this is your way of tunning or not, it just shows a standard in my machines. Also 1 jet size either way made my boat run ok but less performance. Post thermostat jumped 4 jet sizes and still got the same color pattern on my pistons. 1 jet size either way made little changes. So it wasnt as finiky = less wrenching- more ridding.
Futher more what internal combustion engines have thermostats?
All of them. Your car runs for years , change in temp, change in elevation, little change in performance ( obviously before computers were used is what I am referring to) Jet skis are the only liquid cooled internal combustion engine that doesnt use a thermostat. I am not sure why that is.
Again you can form your own opinion, I am not here to debate tunning, performance, if it is right or wrong. It works for me and I like it.
By the way I also run BR7ES plugs too.
I learned these ideas from an old school engine builder for drag cars, it made sense so I used it. :nutkick:

Hmm... Post a pic of the thermostat that you use please...

 

[madscientist]

http://www.fastech-racing.com/product.php?productid=732&cat=176&page=1

ouch!!!!!!!!!!!!!!!!!!!!!!!!!!

http://bpi.ebasicpower.com/pc/SEASK3002/MISCFWC/Inline+Thermostat+Housing+Fresh+Water+Cooling

http://www.k-tuned.com/store/product_info.php?products_id=38

 

[WFO Speedracer]

I think I have one of the Polaris 650 thermostats here somewhere but even it is too big for a Kawi or YAMI engine.It will however work on my X2 since I have the massive cooling hoses that I was running on the Rotax engine hooked to it.:booty:

 

[750SX]

If you are running the same jetting in 80 degree weather with 80% humidity as you run in 40 degree weather with only 10% humidity your boat is not tuned worth a crap in the summertime. Controlling the cooling water temp is only one part of the equation. R.A.D can't be controlled, and that is what affects your air fuel ratio. I don't care what kind of carbs you're running. If you want to be on the edge and have the best performance possible, you need to be jetting down in the summer, and up in the winter.

I do like the thermostat idea. Seems like it would prevent cold seizures, and provide more consistent performance. Only problem I see with it is it's one more thing to get clogged.

 

[Matt_E]

If you are running the same jetting in 80 degree weather with 80% humidity as you run in 40 degree weather with only 10% humidity your boat is not tuned worth a crap in the summertime.

:wavey:
You're welcome try my boat. It performs identical in Summer and Winter. No tuning issues.

 

[750SX]

:wavey:
You're welcome try my boat. It performs identical in Summer and Winter. No tuning issues.

Thanks for the offer, but I don't ride jetworks garbage.


























Just messin. IMO your boat may run good in the summer, but it could be better if you leaned out a bit in the summer.

 

[Matt_E]

It's amazing how you can diagnose this from afar.

No offense, but I'll take the advise of the guy that built the engine over a random stranger on a message board known for its "eggsperts".

 

[750SX]

It's amazing how you can diagnose this from afar.

How can you say this? Maybe Washington has magical consistent air density?:dunno: I live in a climate that can vary from 20-100 degrees Fahrenheit. I ride in weather that is 45-100 degrees and have to adjust my jetting. I also adjust when making trips to lakes at different altitudes. Saying that you can run the same carburetor settings for all temperatures is very ignorant if you have any knowledge of air fuel ratio's and air density. Again, just the way I see it.

Yeah Matt, I agree. There are a lot of idiots on this board.

 

[WFO Speedracer]

How can you say this? Maybe Washington has magical consistent air density?:dunno: I live in a climate that can vary from 20-100 degrees Fahrenheit. I ride in weather that is 45-100 degrees and have to adjust my jetting. I also adjust when making trips to lakes at different altitudes. Saying that you can run the same carburetor settings for all temperatures is very ignorant if you have any knowledge of air fuel ratio's and air density. Again, just the way I see it.

Yeah Matt, I agree. There are a lot of idiots on this board.

The Blackjacks he are running on his boat are not as sensitive to altitude-air temperature changes as conventional carbs,just a word from one of the eggspurts.:stooges:

 

[craven]

Hmm... Post a pic of the thermostat that you use please...

Here is one I had on a previous engine, kinda dirty. It is a canister I made that had a regular car thermostat form Napa. I could easily take it apart to change it or unclog it. I did however put a 1/16 hole in the thermostat to prevent air lock. I also found it beneficial to put an inline filter for the water entering the engine.

Again... I am not arguing tunning and how each others machines run. This works for me, I like it, and that is what I found.
It always amuses me that people get so defencive to what they fear as being different. I wonder how the guy who invented Jet Skiing was treated at first... look at it now.

 

[Matt_E]

How can you say this? Maybe Washington has magical consistent air density?:dunno: I live in a climate that can vary from 20-100 degrees Fahrenheit. I ride in weather that is 45-100 degrees and have to adjust my jetting. I also adjust when making trips to lakes at different altitudes. Saying that you can run the same carburetor settings for all temperatures is very ignorant if you have any knowledge of air fuel ratio's and air density. Again, just the way I see it.

Yeah Matt, I agree. There are a lot of idiots on this board.

I do understand that....sorry for coming across as a bit rough.

As Terry stated, the carbs I run are not very sensitive to air density changes.
There is no performance difference (that I can tell) between the two temperature extremes.
Keep in mind that humidity here never goes high. It's low in the winter and in the summer.
I have had other setups that I have had to change jetting on. This current setup isn't one of them.

 

[madscientist]

Here is one I had on a previous engine, kinda dirty. It is a canister I made that had a regular car thermostat form Napa. I could easily take it apart to change it or unclog it. I did however put a 1/16 hole in the thermostat to prevent air lock. I also found it beneficial to put an inline filter for the water entering the engine.

Again... I am not arguing tunning and how each others machines run. This works for me, I like it, and that is what I found.
It always amuses me that people get so defencive to what they fear as being different. I wonder how the guy who invented Jet Skiing was treated at first... look at it now.

that set up looks like it will cool the cyl. evenly and looks like a pain in the but to get that hooked up to the 4 points. are there slip joints? i can see the benefit to the four point cooling. and a thermostat for the cold seizure issue. i might work on something.