PHP Warning: Use of undefined constant VBA_SCRIPT - assumed 'VBA_SCRIPT' (this will throw an Error in a future version of PHP) in ..../includes/functions_navigation.php(802) : eval()'d code on line 1 High octane fuel in Yamaha 2 stroke
I have had an issue with my spark plugs oiling up after along trolling session ,2 -3 hours . I have been told that using high octane fuel rather than regular unleaded .will help resolve this problem I have a 5 yr old 40 hp 2 stroke Yamaha
Is there any reason not to use 95 octane in my outboard
what oil are you using and are they wet or dry fouling ?
there is no reason not to use anything above what your manual says which should be 91ron, the manual will say ethanol is ok which is kinda true
the engine can run on it but its the boats storage system and infrequent use thats the problem
lower octane fuels burn hotter and faster which can only be a benefit for a engine with plug issues
I personally dont think its the fuel octane rating its more the oil your running, full synthetic is designed from my understanding to be used in engines that are running hard for long durations its a racing oil a lot of people tend to think because its a premium oil its better
Full synthetic oils in a premix outboard idling around would have a high rate of fouled plugs possibly even trolling
I wouldn't say that you have an issue so much as a normal old school two stroke. A quick squirt every so often to burn the oil off has been par for the course with all my two stroke engines.
I only use Yamylube .The outboard is oil injected so I cant control the oil fuel mix ., A friend has suggested that if I switch to high octane fuel I might need to use higher temperature spark plugs. Any comments on this ?
Forget the high octane business, it's not going to help your issue, your motor was never designed to use high octane, as mentioned, check thermostat to make sure motor is reaching proper operating temperature, and just give the motor a bit of a fast run every now and then.....or buy a 4 stroke.
Are u using a lot of oil? From what i have read the oil injection is variable at idle it should lean right out and at full throttle it oils at 100:1 or less
I dont feel that my oil usage is excessive ,the local Yamaha service tech told me the oil injection is not adjustable any thoughts on the high temp spark plugs?
Does the manufacturer allow hotter spark plugs to be ran in the engine? I have never been real tech savy in electronics
What do your plugs look like after you have been out idling or trolling for a day can u post pics if possible?
If your worried about going thru heaps of spark plugs u can heat a fouled spark plug with a blow torch untill the fouled end goes cherry red and they work again
Sent from my SM-G900I using Ausfish mobile app
I’ve had the same engine but was 10 years old when I got it
it was premixed and would foul plugs if I trolled for a few hours so I just gave it a squirt every hour and wouldn’t happen
But then the 30 hp 3 cylinder triple carb engines I had wouldn’t do it and could troll how ever ling you wanted
Is this a new thing it’s doing or always done it , yamalube is decent clean oil
NH, The old 2 stroke can be a cantankerous beast when used for trolling and it is really hard to work out the best way to go as every brand and even models within brands can be different.
Because a hotter Spark Plug has a longer insulator nose length, heat transference from the firing tip to the cooling system occurs at a slower rate. which in turn keeps the spark plug temperature high, allowing the plug to self clean and prevent fouling, or so the theory goes, so it's worth a try as they are relatively cheap, on the other hand I have had some success with Iridium Plugs but they are quite hexy and may/may not do it for you in which case you will have spent a fair bit of money only. This would be the last resort after trying a hotter plug.
As others have said give it a good squirt of power every now and then to clear it as much as possible. I used to do it when trolling up in the Daly but as I got older I found trolling starting to get a little tedious so no longer do it. Good luck on finding an outcome.
Posting Permissions
Reply With Quote