What oil?
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
What oil?
Hi Team.
I usually use ordinary mineral 20/50 motor oil for fuel mix for my 40+, this seems to work ok, makes the usually amount of smoke etc, but now I own a diesel camper. Any reason not to use diesel engine oil instead? Given that oil is pretty much...well...oil, I'd be interested in hearing the pros and cons. It's more expensive, but I dont use much and it would be one less thing to carry.
I usually use ordinary mineral 20/50 motor oil for fuel mix for my 40+, this seems to work ok, makes the usually amount of smoke etc, but now I own a diesel camper. Any reason not to use diesel engine oil instead? Given that oil is pretty much...well...oil, I'd be interested in hearing the pros and cons. It's more expensive, but I dont use much and it would be one less thing to carry.
Re: What oil?
I believe a straight 30 grade mineral oil could be used. I would think that most engine oils contain alot of additives. Diesel oils in particular have a lot of detergents to remove carbon and crap.
I guess it's your choice but your going outside the boundaries of what's specified.
I myself use a plain two stroke oil which is designed for the job. It maybe easy to use one oil for everything but it's also not hard to carry the right oil, in the scheme of things it's not that dear especially if you get extended engine life.
I guess it's your choice but your going outside the boundaries of what's specified.
I myself use a plain two stroke oil which is designed for the job. It maybe easy to use one oil for everything but it's also not hard to carry the right oil, in the scheme of things it's not that dear especially if you get extended engine life.

Cheers Rolf.
www.acmeengineering.com.au
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Re: What oil?
If you *TRUELY* want a blue cloud use Castrol R30!
(Caution, bearings should be cleaned and lubed with the new oil when changing either way between conventional oils and Castor oil based lubricants as they are not compatible. Castor oil based lubricants can cause rapid carbon buildup)
Otherwise, TCW3 two stroke oil is your best bet, otherwise straight 'pure dinosaur' SAE30 oil with MINIMAL ADDITIVES. i.e. an economy or 'classic' SINGLE GRADE oil is usable. I wouldn't use multigrade oil for diesels except as a 'Get me home' emergency mix.

Otherwise, TCW3 two stroke oil is your best bet, otherwise straight 'pure dinosaur' SAE30 oil with MINIMAL ADDITIVES. i.e. an economy or 'classic' SINGLE GRADE oil is usable. I wouldn't use multigrade oil for diesels except as a 'Get me home' emergency mix.
Re: What oil?
Multigrade oils are generally not recommended or considered suitable
use a straight non-detergent sae 30 oil if you must use an automotive oil and two stroke oil is not avaiable.
At one time ( pre TCW oils I guess) a 2 stroke motor-cycle oil such as Castrol TT was recommended.
But now use an outboard 2 stroke oil of TCW-3 specification. Quicksilver is a readily available brand.
If you also convert to 25:1 ( assuming the engine is of an age that can be converted) smoke will be a thing of the past.
use a straight non-detergent sae 30 oil if you must use an automotive oil and two stroke oil is not avaiable.
At one time ( pre TCW oils I guess) a 2 stroke motor-cycle oil such as Castrol TT was recommended.
But now use an outboard 2 stroke oil of TCW-3 specification. Quicksilver is a readily available brand.
If you also convert to 25:1 ( assuming the engine is of an age that can be converted) smoke will be a thing of the past.
- Charles uk
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Re: What oil?
Prior to the advent of TCW-3, 30 grade motor oil was the specified oil for Seagulls the old fashioned stuff not the super dooper, multigrade, synthetic, high detergent brew, some of the Kiwi racers swear by it, better performance they say.
Make it idiot proof and someone will make a better idiot.
Re: What oil?
My handbooks ( 1973 and 1974) say a light grade of engine oil suitable for two-strokes. They go on to recommend BP Energol two-stroke oil, Castrol TT, Duckhams two-stroke engine oil, Esso two-stroke 2T, Mobilmix TT, Texaco Motor oil 2T. Shell (2T) two-stroke and Fina YM two-stroke oil.Charles uk wrote:Prior to the advent of TCW-3, 30 grade motor oil was the specified oil for Seagulls the old fashioned stuff not the super dooper, multigrade, synthetic, high detergent brew, some of the Kiwi racers swear by it, better performance they say.
They say If these are unobtainable use a good quality SAE30 non detergent 'straight' mineral oil. Multiple viscosity lubricants such as SAE 20W-50 grade are not suitable
- Niander101
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Re: What oil?
"but now I own a diesel camper"
happy days ! so do i
vw T25...
Wonder what harm the engine oil in the mix would do?
make it coke up more perhaps?
happy days ! so do i
vw T25...

Wonder what harm the engine oil in the mix would do?
make it coke up more perhaps?
Re: What oil?
My camper is a wee bit bigger, I removed the really rusty Transit from underneath a commercial camper, mounted the box on a flatdeck Isuzu truck and filled in the gap left by the original cab with freezer panel for outstanding storage. The pram dinghy rides sideways across the back on a rack. Works well.
The detergent thing makes alot of sense, diesel engine oil will be full of the stuff. Two stroke oil is easy to get and the same price or cheaper as 30 weight, hardy worth the bother. I thought about converting to 25:1, but again, hardy worth the bother. Sadly I don't get to use it as much as I would like.
The detergent thing makes alot of sense, diesel engine oil will be full of the stuff. Two stroke oil is easy to get and the same price or cheaper as 30 weight, hardy worth the bother. I thought about converting to 25:1, but again, hardy worth the bother. Sadly I don't get to use it as much as I would like.
- Niander101
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Re: What oil?
Yes having a van is infinitely useful could fit about 50 seagulls into it 

Re: What oil?
I have been reading about piston seizure and holing in 2T motorcycle and scooter engines caused by ethanol in the fuel washing the bores of mineral based oil, the recommended cure seems to be a pure synthetic racing oil ! . My seagull is on 10to1 mineral oil so I doubt if it would be possible to have a problem but at 25to1 on the later motors who knows . Has anyone else had problems ? Perhaps a constant load /speed motor like an outboard the situation will not crop up ?
- Collector Inspector
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Re: What oil?
TCW3 Outboard at your preferred mix.
Castrol 4T is SAE30 basic oil at your preferred mix Old School if you wish.
Either/Or
Nothing else........period.
B
PS: "Perhaps a constant load /speed motor like an outboard the situation will not crop up ?"...........IS, where the problems Crop Up by the way?
Castrol 4T is SAE30 basic oil at your preferred mix Old School if you wish.
Either/Or
Nothing else........period.
B
PS: "Perhaps a constant load /speed motor like an outboard the situation will not crop up ?"...........IS, where the problems Crop Up by the way?
A chicken is one egg's way of becoming others
Re: What oil?
I notice that you are based in Australia , do they add ethanol to your fuel ? and what do you mean by constant speed/load being the problem ? I have only heard of motorcycle/scooter engines being affected not outboard motors.
- The Tinker
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Re: What oil?
If you use two stroke oil make sure it is outboard type as it burns at lower temperatures. Some two stroke oils need a higher temperature than a seagull runs at, so it burns.
Re: What oil?


- Collector Inspector
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Re: What oil?
Ah, good question that.philmel wrote:I notice that you are based in Australia , do they add ethanol to your fuel ? and what do you mean by constant speed/load being the problem ? I have only heard of motorcycle/scooter engines being affected not outboard motors.
Perth is on the west coast with local refinery. No ethanol added for local which is a good thing. Perth WA is THE most remote capital city in the world....which.....if you can afford living is really COOL! Way way away from anything etc.
The Eastern seaboard (Other states including the NT) have ethanol blended in. They have pump choice of course but E fuels are cheaper for them I think?
Anyway.................Perth has only the good stuff so far

A bit like Beer in that you only want to drink local product?
https://littlecreatures.com.au/
SO GOOD!
Cheers
B
A chicken is one egg's way of becoming others