Just purchased a 2 stroke outboard

That brought back memories, Darley Moor in the 70s, mate had a Yam TD2? twin, cutting edge, fecking things would seize at the drop of a hat. He decided to add a bit more oil, just in case, took him ages to work out that it was leaning the mixture and that was why he was putting holes in the top of his expensive pistons!
Stu
 
Just been told stored fuel fine for certainly 3 years... so what do I know. Something a marine engineer once told me, but perhaps he had just invested all his life savings in a petroleum company.

Also been advised for smaller 2 strokes accuracy less important. All I know is a few years back I slightly overdid it, by using the scale on the side of the oil bottle & on my 30year old 80hp Merc I left a blue vapour trail. Nice if I was one of the Red Arrows... not so good on a boat! /forums/images/graemlins/tongue.gif
 
[ QUOTE ]
I left a blue vapour trail

[/ QUOTE ] For a time I used straight sae30 oil in my Seagull on the tender, and that was before I converted it from 10:1 to 25:1.
30 years later you can still see a blue haze from Hardway up Portsmouth Harbour to the moorings!
 
Not at all, very tongue in cheek. I was interested to hear what you had to say about fuel life. I was given the impression that by adding 2 stroke oil the fuel then started degrading faster than without. But I have used fuel that has been stored in my speedboat (in a sealed and dark recess) that is certainly 6 months old and it has been absolutely fine..... so I bow to your greater knowledge.

The one bit of advice I was given with my two small 4-stroke outboards I have (Suzuki 6hp, and a Honda 2hp), is to drain the old fuel out the carb if leaving for a few weeks otherwise with these small carbs and jets the fuel can gum up and hinder starting. It is interesting that this task is seeming made very easy as both have quick screw release drains of the carbs so it is a 20 second job on both engines.
 
Gumming is a possibility with all modern gasolines as none are true gasoline as the old days. All are now blends. market pressures of profit margins etc. have pushed virgin fuels out.
The gum you refer to is based on Oxidation of the blend mix - and in a non-vapour sealed carb - this is likely.

In the trade - Oxidation Stability analysis is nicknamed "Gums" ! for obvious reasons as you can see now. A fuel has a specification for time it can resist forming gums when at a set temp and oxygen bubbled through it ( it's more involved than that - but you get the idea) - this speeds up the process to give us an idea of the stability of the gasoline blend for storage and use.
It is illegal now in EU and many countries to use certain Octane enhancers but it's not unknown for cargoes to get mixed or re-routed ... ending up in the supply chain. Some of these enhancers have to be kept cool, in the dark otherwise they drop out dark red sediments that are mistaken for gums.

Draining carbs on any motor is good idea if left for any significant period .. if engine can be run dry by shutting fuel tap - then that is often good enough. I know that some will comment that manufacturers don't advise doing this due to the leaning out of fuel intake ... but is it really that damaging ?

Manufacturers of engines whether petrol or diesel - tend to stray from the real fuel path and make statements about use of fuel ignoring that fuel industry has moved on a long way from the old days ...
 
[ QUOTE ]
The one bit of advice

[/ QUOTE ] Yes that is probably sound advice. There's a big difference between storing fuel in sealed containers and leaving a carb bowl full, most of which is going to evaporate and in the case of 2T mix leave the oil behind.

I always run my outboards dry by disconnecting the fuel supply or tuning off the tap, according to the outboard, and allowing them to idle until they stop. Little problem with 4 strokes as far as I can see, although briefly they will be running very lean. Problem with 2 strokes is that they are also running out of lubricant. I do not believe this is a problem with small engines because at idle they are well over lubricated anyway. The experts advise against it with larger engines with multiple carburetters. They say that the upper carbs run dry before the lower ones so that the upper cylinders are then being driven by the lower ones for a period with no lubrication.

On the other hand who drained the petrol from their car carbs in the days when cars had carbs if the car was to stand idle for a week or so.
 
Being quite new to this forum (and indeed any!) I find myself reading posts like this and being impressed by the wealth of knowledge we have available to each other for advice and help on topics we may not be up to speed on.

As an example I'm now feeling overly confident in the subject of modern fuels!! /forums/images/graemlins/confused.gif
 
My main business is Fuel Blending and Quantity / Quality determination for Oil Traders / Oil Company's.

We oversee a large %age of EU fuel ....

Gasoline we don't do so much of now as I dropped out of blending for African Markets with the quality issues. Diesel - actually proper name is Gasoil - we do 100's thousands of tons a month ! So we may have an idea of whats in it...

We blend from straight summer spec right through to Arctic grades.

We also cover lubricating and Fuel Oils .... Butanes and Propanes as well as Crudes.

That's not to say we don't get odd other grades and cargoes put to us for work.

We have expertise to cover Fertilizers, Grain, Coal, Peat, Scrap metals ferrous and non-ferrous, radioactivity checking, Petroleums, Chemicals and Gases ... in fact if it can be shipped - we can do it !

We've even done special order lab work for Forensics.

We were asked one time .... now this is straight up honest ! - a guy appeared at the lab door with a paper bag. He wanted his wifes knickers tested for 'other' material. Honest ! With straight face we accepted the work and proved that his wife had not .......... if you know what I mean. How ? Knickers were washed in solution and that was tested ...

Interesting life !! /forums/images/graemlins/wink.gif
 
Very interesting.... but somehow everyone else's job/occupation always seems to be more interesting than your own...(unless you are Dario Benuzzi, the chief Ferrari test driver) /forums/images/graemlins/smile.gif

Sorry, got off main topic and don't want to be thought of as high jacking a post.. signing out.
 
I could not find a super laboratory accurate connical measuring cone, so bought a babies feeding bottle with markings on the side from local pharmacy.

Works well enough for me.

And another vote for Quicksilver TCW3
 
When I had a Seawych with an outboard as the main engine I used to carry my ready use 2T oil in 100ml plastic bottles so that I always had a measured dose for a 5 litre can to hand.
 
[ QUOTE ]
When I had a Seawych with an outboard as the main engine I used to carry my ready use 2T oil in 100ml plastic bottles so that I always had a measured dose for a 5 litre can to hand.

[/ QUOTE ]

I know someone who used 35mm Photo film canisters for same reason. Volume though I don't know.
 
[ QUOTE ]
Volume though I don't know.

[/ QUOTE ] They probably vary a bit but the one before me is 30.0mm diameter and 50.0 mm deep. I'll leave the arithmetic to those who are good at such things.
 
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