Oil injected two strokes disconnect or not?

[beatle]

Just returned from the club and a disscussion took place amongst a group of friends as to whether you should or should not disconecct the oil injection systems on two stroke outboard motors. Some say you should disconnect it and just mix your own oil and others say to leave it as the engine manufacturer has made it.- Any reccomendations?-Beatle. ??? ??? ???

[blaze]

Hi Beatle
never had the need to worry before now, always had o/boards that had to premix, just purchased a late model myself and after some lenthy discussion with a really trusted outboard mechanic, i am going to run the motor as per specifacations. I am also a mechanic by trade of 25 years (try hard not to be)
cheers
blaze

[basserman]

well in have a injected 2st and haven't had a prob yet and no one has sugested for it to be removed! :)

[grinder]

The makers of outboards these days seem to have been at it for a while and in most cases seem to have got it right they would spend prob millions on r&d each year to get outboard motors to this point.
just think how much money they could have saved if they had of listened to some joker in the pub in my opinion if it is ment to have oil injection leave it alone and use it as it was first ment

Grinder

[Kerry]

If it ain't broke ... then don't fix it. If you don't want an oil injected motor then shouldn't buy one in the first place, just buy a straight premix version to start with.

In any case it usually doesn't hurt (depending on the make/type of injection) to run a little oil in the fuel in oil injected motors anyway as it can help lub things as some inject before the carb and some after.

Too much oil (within moderation) is not as big a problem as too little oil.

Cheers, Kerry.

[zoley]

Beatle.
Oil injection in modern 2 strokes have a lot less problems than
the older models. In the old days it was not uncommon for
owners to bypass injection and premix instead.
It is hard to forget the feeling you get when in the middle of
a bar crossing on a rageing run out tide,suddenly you hear
that dreaded buzzer sound and your motor will only give you
minimum revs. My theory after that event was if you have to
pour oil into a container anyway why not just pour straight
into the fuel tank and save a lot of money on the initial purchase and say goodbye to injection worries for good.
If you have a outboard mechanic that you really trust, ask
him what was the cause for the last 10 major repairs he did
on 2 strokes in the over 6 year old range. ( 60 hp and over)
cheers.

[Kerry]

.... If you have a outboard mechanic that you really trust, ask him what was the cause for the last 10 major repairs he did on 2 strokes in the over 6 year old range. ( 60 hp and over)

In recent times the cause of many major repairs appears to be most probably caused by bad/old fuel, which might look like an oil problem and the fuel companies would like everybody to think it's a oil issue but it ain't.

The best I've seen on one guys bench was 13 motors at ONE time, all makes, generally the 3 cyl/V4/V6's and all with the same problem, bad fuel.

Cheers, Kerry.

[coasty]

bad fuel is the biggest destroyer of motors. i dump whats left at the end of the day in the neighbors young blokes car. it doesnt affect the heap but he gets some free running.
oil injection is pretty good now days so i'd leave it alone. always a bad story. just ask greg joyes how wrong oil ruined his out board. stick to the specs and it will be right.

[littlejim]

When my motor servicer sold his business it really cheered me up when one of the guys working for the new bloke said he always 'ripped out' the oil injection. Told him to keep his hands off mine. To me the oil injection is a blessing compared to guessing how much petrol will be needed for a fill and then calculating 1:50 for the amount of oil to add and then pouring that into measures and then into the tank. Much easier to keep an oil tank filled up and just pull into garage and fill the petrol like for a car. My oil injection has worked OK so far for 13 years.

Wouldn't mind knowing what Kerry and the others mean by 'bad fuel' and what it does to motors. Some might remember what Shell and Caltex said to me when I asked them about it. They indicated that it would take about a year for the more volatile fractions to reduce to where it was a problem. This would take longer where the fuel was sealed in a tank, and where fresh fuel was being added the effect would would be minimised. I personally don't chuck any fuel away and don't know of any problems over a decade, but would still like to hear what could happen if it's factual rather than 'I reckon'.

[blaze]

I would also like to know how long before good fuel turns bad, this is the first under floor tank i have had, I have also never thrown fuel out, I also use boat at a minimun of once a fornight, thats very rare, normally more. The first tank of fuel I am putting through this merc is premix until I am confident in the injection.
I have been told the most frequent cause of o/boards is water, backing into a sea, etc
cheers
blaze

[Kerry]

.... Wouldn't mind knowing what Kerry and the others mean by 'bad fuel' and what it does to motors. Some might remember what Shell and Caltex said to me when I asked them about it. They indicated that it would take about a year for the more volatile fractions to reduce to where it was a problem. This would take longer where the fuel was sealed in a tank, and where fresh fuel was being added the effect would would be minimised. I personally don't chuck any fuel away and don't know of any problems over a decade, but would still like to hear what could happen if it's factual rather than 'I reckon'.

Littlejim, "bad fuel" generally equates to "old fuel" and many workshops started asking questions around the mid 90's when so many engines started failing with identical symptoms, such as holes in pistons. Fuel comnpanies obviously weren't in a real hurry to come clean and maybe some are still trying to play down the situation but these days most are prepared to acknowledge that old fuel is a problem and not just a "I reckon".

Probably as more moved to ULP as leaded was phased out the problem got worse and as I mentioned above at one workshop I frequent back in the late 90's there were 13 engines on the bench, all different makes but all with almost identical failures, holes in the tops of pistons. It really wan't all that difficult to see what the common link was and basically acknowledged by the individual owners.

It is fairly widely accepted that ULP can have a shelf life as low as 6 weeks and some even say 30 days and these times are certainly reduced for pre-mix fuel.

Actually in the U.S where EPA requires even lower engine emmisions the extra additives and experiences have made some recommend that the weekend fisherman who use their boat once a week take extra precautions and use fuel stabilizers but 7 days I don't think it's that bad here, not yet anyway.

Sealed tanks don't have has much problems but then how many boats, especially with under floor tanks are sealed.

Topping up with new fuel is one way of reducing the possibility of a problem but relative amounts must be taken into account to achieve any improved result. Even adding PULP is an option and gives things a bigger ummp.

But if my motors blow up due to old fuel and regardless of what any fuel company has stated, I'm the one who has to wear the bill, and until the fuel companies start wearing the bill then we just have to take all the precautions possible and simply not trust PR. # # #

Cheers, Kerry.

[littlejim]

Kerry,

what you say sounds quite reasonable. What impresses the punters is statements like 13 motors on the bench with burnt out pistons. But of course how do we know that old fuel burnt out the pistons? Could be the owner didn't mix the right ratio of oil in the petrol, his oil mixer wasn't working, or he hadn't used the thing for five(eg) years.

Personally I am prepared to take what Shell tell me is the life of their petrol (about 12 months) they'd be crazy to go telling fibs and they have to be more expert on the subject than the bloke with 13 donks with burnt out pistons, who knows all about fixing motors, isn't an expert on fuel technology, just has a 'gut' feeling about what has happened.

If you try to use a bit of common sense I would suggest that those who are chucking away fuell as soon as they come in from a trip are wasting dough, although if you put it in the car or lawnmower it is just a bit of extra work. if you are using your boat every month or few months I suspect you wont have a problem. If you only use it once a year or live in a tropical climate maybe it is worth doing something about it.

Just hate seeing newbies to boating being told stuff that equates to having to believe that fairies live in the bottom of the garden. I was a newbie a while back it is at times hard to tell the bull sh*t from the facts.

[basserman]

one thing i do know is some fule is better than other and more so where the fule is in rural or buget servos so when buying it got to a bigger servo or a place where you know the fule is good for me that means the caltex at port and i do know that some people have had trouble with thier motors 2st and 4st by useing bad fule i do how ever drain my tank and clean it once a year that way you get rid of the build up the old fule can leave behind

[Kerry]

Littlejim, NO it's not good when people (newbies) aren't aware of the facts but it's also no good just to sit back and let people think there are no fairies at the bottom of the garden ;D

If you've ever seen a series of motors that have failed for this reason then you would also see that it wasn't an oil failure problem of any sort as a oil failure leaves no oil anywhere and a lot more failures than simply denotation problems.

Sure oil companies would be crazy to start telling fibs but of course that didn't happen when diesels suddenly started failing did it ;). Took quite some time for the actual facts and the fact that some smart oil company had changed/modified the fuel and of course had simply forgotten :-X to tell anybody, until they were looking down the liability barrel.

I could go further into what happened with those donks and the people who took interest in those motors (and some other motors around the country side as well) but might destroy the fairy myth as well. Gut feeling really didn't come into this issue but personally people can believe what they like, that's their right, their motor, their cheque book, their decision.

However if one adopts some rather simple fuel management policys then any possible risk can be reduced, but some will take the risk and obviously some won't and believe that what fuel companies state is unquestionable. There is a choice.

Once the thought that keeping tanks full reduced the water problem but really water/condenstation is something that can be controlled/managed, now the concept is keep tanks empty, fill up before a trip and plan trips so that one generally doesn't have umteen litres of fuel left sitting in a tank with nowhere to go. It really isn't all that difficult to do.

Nobody has to go around chucking fuel away as soon they come home from a trip but the whole issue of fuel is something to be aware of and managed differently in an outboard environment compared to motor vehices.

Cheers, Kerry.

[NQCairns]

Gotta say I am with Kerry on this, it was amazing to sit and watch the low sulfur con-job uravel in the face of the oil/petrol companies. They were shafting a far far stronger consumer base than than us hand to mouth boaties, without finally the media blowing it in the face of our elected it would still be denied.

If my fuel is 2 weeks old then it gets a top up with pulp, if over 4 weeks then it gets used in a less tempremental engine than a 2st O/b (dont forget the fuel still in the fuel line).
I do all this not only because i think the fuel standards are inadequate on average from the fuel tanker sometimes but because my fuel comes from a hole in the ground before my fuel tank and I have been stung a few times before with poor fuel.

As easily as a doctor can diagnose a broken bone a mildly experienced mechanic can a fuel problem after the engine has broke.

An experienced one can do it just by looking at the piston tops before it breaks. A relitively cheap fuel test by a lab can then nail it.

Good luck to any trying to get compensation until enough people (thousands) all get the same problem at the same time. Best to look after yourself first, it's cheap insurance.nq

[dnej]

I have a Mariner workshop manual , and the manufacturers recommendation is 30 to 60 days tops. The problem is the gum deposits as well as the low octane. How can Shell say one thing , yet there be proof to the contrary
I know a guy who doesnt get out much, and is to the service mechanic 3 times a year with fuel gumming problems.
45 Days is my limit.
David
Ps you can actually smell the difference

Since I posted this, I phoned Shell,1300 134555, spoke to Chris.
He said no more than 60 days when you have oil in the fuel. The solvent in the two strike oil disappears over time, and the oil will not remain mixed in the fuel, and actually separates, forming a gum as I mentioned.

Unmixed fuel in a sealed, note sealed can is Ok for up to six months or more. Remember under floor tanks have breathers, and are not sealed

[littlejim]

Don't want to keep this one going for ever, so this is my last comment.

Kerry: "bad fuel equates to old fuel".

Did anyone check whether these owners had been buying fuel from cheaper places that 'cut' the fuel with thinners and kero etc, remeber the stink about that?
Had any of the donks been rebored? The greater capacity after the rebore means the donk will run leaner and hotter unless the jets are changed to compensate. Holes in pistons would normally mean it is running hot I would think. During our go karting learning phase we often ran it too lean, in that engine the plastic cage for the big end bearings used to melt. Same result engine stops.
Not quite sure that enough possibilities have been considered by kerry's mechanic to blame the problem on fuel that is over a month old.

Kerry: "widely accepted that ULP can have a shelf life as low as 6 weeks".
Accepted by Kerry and a number of boating people. Those I have spoken to, not all boaties, put it in there car/boat/lawnmower and assume it will be OK after they come back from holidays etc. Not quite as 'widely' as among Kerry's associates. Not accepted by Shell and Caltex who make the stuff. They thought that it would be OK for about a year.

Kerry: 'Diesels started failing".
I was only on about ULP, not diesel. In Kerry's favour, we did have the stuff up a while back with aviation fuel from the Mobil(I think) refinery. Don't know of any stuff up, like the diesel one, or the aviation fuel one, with ULP.

DNEJ:Gum formation problems with oil/fuel mixes. Agree. Any one who owned a Bantam Beeza, or other two stroke where you mixed the oil in, had to take this into account. In fact some of the oils you put in are a mix of several different types. I always give the oil a good shake, just in case the lighter ones haven't gone up to the top and the heavy ones down to the bottom. But here we were I thought talking about fuel without any oil mixed in.

Last statement before I shut up on the subject.
I realise Kerry is trying to prevent any of us suffering from severe angst from something he perceives as a problem. I just think that the problem isn't as severe as he does. This 'think' is based on not bothering to chuck away old fuel over the last 12 years with the boat, and over 40 years with the car. I buy the fuel from places with a good turnover who don't look as though they 'cut' their petrol.

Find I spend enough dough on the boat and the fishing gear without wanting to waste even more by doing unnecessary dumps of perfectly good fuel out of the boat tank.
Promise to shut up now on this topic. (Would never argue with Kerry about GPS's or double ended dipsticks.)

[Kerry]

Don't want to keep this one going for ever, so this is my last comment ....Promise to shut up now on this topic.

Yeah, probably best you do before you stumble. LJ shell man says 1 year (12 months), Dnej's shell man says 2 months so either we've actually got one shell man too many or LJ's PR bandwagon simply rolls on and on.

Six weeks is what some call a conservative safety margin considering some of the other variables.

But LJ it's your motor, it's your decision just like your opinions and you can do will all of them exactly what you please.

Cheers, Kerry.

[littlejim]

Kerry's personal way of arguing his point requires me to break my promise.

"LJs PR bandwagon rolls on."

I was in the Air Force all my career fixing fangs. Now I'm just an old retired fart who bought a boat. Got nothing to do with plugging fuel.
To me someone like Kerry who is advocating throwing away gallons of perfectly good fuel is more likely to be on the 'PR bandwagon' of a fuel company than someone advocating not to do it.
However, as I said, I suspect that both of us are trying to present a point of view based on our personal experience, hopefully without rancour, and those looking at it have to make their own decisions on what they are going to do themselves.

[NQCairns]

LJ whats a fang? cheers nq

[Kerry]

.... To me someone like Kerry who is advocating throwing away gallons of perfectly good fuel ....

Now where did I say that? that's not good fuel management.


is more likely to be on the #'PR bandwagon' of a fuel company than someone advocating not to do it. Now that is simply someone lost for an assumption. [smiley=thumbsdown.gif]



However, as I said, #I suspect that both of us are trying to present a point of view based on our personal experience, hopefully without rancour, and those looking at it have to make their own decisions on what they are going to do themselves.

Yes and that what it comes down to, the information for people to make their own decisions as at the end of the day, people have to wear their own decisions.

Lot of difference between 12 months and 2 months, isn't there ? and from the same source ?? somebody needs to correct something other wise that is simply confusing information.

Cheers, Kerry.

[dnej]

Well I am sticking to the manufacturers recommendation, and Shells advice about shelf life of mixed and unmixed fuel. There is to much evidence to ignore damage done in the past.
David