Pre-Mix ??

[StIhL MaGnUm]

Ok so I was told to run a pre-mix of 32:1 in my 385xp so tell me if I'm correct to get 32:1 I add 6.4 fl.oz to 1.5 gallons of 93oct gas right?I got a bunch of these Husky 6 packs of 6.4oz bottles for 2.5gls,that I need to use up..What are the advantages to running 32:1 instead of 50:1 or 40:1???

Thanks Rob..

 

[bwalker]

32:1 is equal to 4oz per gallon. 1.5 gallons would need 6 oz of oil.

 

[bwalker]

32:1 is equal to 4oz per gallon. 1.5 gallons would need 6 oz of oil.

 

[StIhL MaGnUm]

Are there any special adjustments I will need to make to the saw when I switch to 32:1 over the original 50:1 ratio???

Thanks for any info..

Rob..

 

[treeclimber165]

Buy spare spark plugs to replace fouled ones in the field, and either remove the muffler spark screen or clean it regularly.

 

[StIhL MaGnUm]

Thanks for the tip I already got rid of the sparl screen and I always keep a few spare plugs around anyway's.I was just wondering if I would have to make more carb adjustment's??


Thanks Rob..

 

[rbtree]

I switched to 32:1 mix ratio last winter. I have had no plug fouling problems, excessive smoke, or carbon buildup in exhaust ports.

However, the added oil (which is lube, and doesn't burn) will result in slighter less fuel for the same air, so a slightly richer setting is needed on the carb.

 

[bwalker]

However, the added oil (which is lube, and doesn't burn)

RB, That is not a correct statement.The oil does indeed burn. Carb adjustment differances should be very slight when going from 50-32:1 and you should not foul plugs anymore often with more oil.

 

[StIhL MaGnUm]

Thanks for the help guy's I appreciate it

Rob..

 

[John in MA]

I just thought I'd add this tidbit. Old Seagull outboards that ran at 8:1 or 10:1 needed new main jet when you switched to 25:1.

 

[tony marks]

bewalker. is it your opinion that exstra oil in the mix wont cause fouled plugs ,possibly due to the oils being better quality now days ,or u just dont believe
more oil in the mix can cause plug fouling. just curious.

 

[rahtreelimbs]

Originally posted by rbtree
I switched to 32:1 mix ratio last winter. I have had no plug fouling problems, excessive smoke, or carbon buildup in exhaust ports.





Ditto. Rich

 

[bwalker]

bewalker. is it your opinion that exstra oil in the mix wont cause fouled plugs ,possibly due to the oils being better quality now days ,or u just dont believe

Tony, The deposits that lead to a fouled plug are caused by low plug nose temperature, not the amount of oil in the mix. Low plug temps are caused by jetting that is to rich(mostly on the low speed circuits). That being said todays oils do burn cleaner than the products of years past. Any iso egd oil will provide good service and minimal fouling when ran at 32:1 in a saw.

 

[don]

My saw won't run at 32:1 ratio

Listening to this site earlier I changed from 50:1 Stihl black label oil to 32:1 ratio and it just would not easily start. Gas octane around here is at 91. With the saw hot it will run 32:1 with no problem. Even with 50:1 I still get oil/unburnt fuel out the exhaust. If I used I higher oil mixture will the saw have longer life?

 

[treeclimber165]

Re: My saw won't run at 32:1 ratio

Originally posted by don
Listening to this site earlier I changed from 50:1 Stihl black label oil to 32:1 ratio and it just would not easily start. Gas octane around here is at 91. With the saw hot it will run 32:1 with no problem. Even with 50:1 I still get oil/unburnt fuel out the exhaust. If I used I higher oil mixture will the saw have longer life?

ummmmm.... a different ratio won't fix your carb adjustment. Sounds like your carb isn't properly set up.

 

[don]

Whst do you recommend treeclimber165

on an 066? carb adjustment

 

[treeclimber165]

Yes, carb adjustment.

(assuming all the other maintenance items have been addressed- air filter, fuel filter, fuel lines, no leaks, etc.)

 

[StIhL MaGnUm]

Well I guess 32:1 it will be from now on..Thanks for all the advice guy's I appreciate it..


Thanks Rob...

 

[tony marks]

guess some people just hard headed but ,the things run and last rite on, crank easy . if it aint broke ,dont fixit. 50-1 an 90 octane,for me . to each his own.
the difference in plugs causing fouled plugs ,i can understand though.
i always thot it was too much oil in the mix. well learned something new to add to my vast knowledge base

 

[mikey]

Mix ratio

Unless the engine is modified or used in a different manner(climate,rpm, load etc) or if you swtched oil types,than it was designed,why would you want to change what the manufacture recommends?If it siezed and you told the rep. that you changed the pre mix ratio,would he honor the warranty? More oil=more protection & power or more heat & fouled plugs?