Bad Petrol from Petrol Stations - Yeah Right

Bigplumbs

Bigplumbs

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I have recently read a few posts where people have suggested that their boat engines have stopped/broken down or similar because of 'bad' Petrol from 'road' filling stations.

Does anyone actually believe this. I think it is one of those urban myths and does not happen. I feel other issues are blamed on 'that petrol'

Interested in the views that might follow
 
Mallorca has a poor reputation for petrol , speciacally water.

I have just had water in my Williams tank. Seals are good so pump seems the source.

The only difference on some marine engines is huge bhp per litre. A Willaims has more power per litre than a Porsche 911 and they don’t like bad fuel. I suspect big outboards are the same.

I would be surprised if a uk fast turn over fuel station has an issue.

I’m Mallorca the petrol sales will be small by comparison to diesel which may explain it. I guess it is the same in the uk but I have no real explanation as to why there should be water in it.
 
I am interested in keeping this thread going but haven't got a clue about the reality of 'bad' petrol.
In the rural depths some people used to avoid the outback garages for fear of water in the petrol (haha), now we virtually have none so they just moan about the price.
Logically I can only assume there are limited oil refineries that process petrol. I hope that is correct.
Do they make inferior stuff for bad payers perhaps? Surely it is more-or-less the same stuff?
Its not like making beer is it.
So I am trying to bump this thread with blitherage, thank you for your patience.
 
Supermarket petrol is usually good because, as jrudge says, their turnover is enormous so petrol is always fresh. Apart from cockups! The UK press reported two cases in September where Tesco managed to put diesel and then water into their petrol storage tanks which caused multiple vehicle breakdowns.

My ex had a campervan which didn't get used over winter and she used to keep the tank almost empty during this time because she was told by a mate of hers who works in the fuel supply industry that petrol 'goes off' over time, whatever that means.
 
Petrol does go off over a long period, but whether it goes off enough to affect the way your engine runs depends on the engine. I've got a Suzuki 6hp outboard that won't run on petrol that is 6 months old, but the same petrol works fine in the hire car ;-)

Back to the op, I've had some bad petrol from a UK petrol station, in our car, it required new injectors,fuel filters and fuel lines to put right the damage that was caused, we took the garage to the small claims court (and won) for the damage they caused. In our case this was contaminated petrol, contaminated with water and all sorts of sludge . But that's just one incident out if thousands of fill ups for me, so just one of those things rather than evidence of a wider problem with petrol stations in general.
 
I have read on many car forums how buying 98ron super unleaded is pointless as petrol stations do not sell that much and it degrades.I'm sure Firefly624? of this parish doesn't have this problem as his station supplies Mclaren lol. (and would have a better view of this thread.) :D
 
You dont get bad Diesel, In December I bought a Land Rover Defender which had been stood for 9 years and after fitting a battery it started third turn of the key, 10 months later its still running on the original diesel, (only used it around the farm)
And a dumper I put into storage 12 years ago started and ran well after fitting a new battery.
My next boat will be a Diesel.
 
Sometimes in cars particularly high powered cars that spec 98 Ron if you happen to fill up with 95 once or twice consecutively the Check Engine Light - CEL comes on .
A refill even top up 1/2 full with 98 is usually enough for the CEL to go out spontaneously.
Modern Ferrari’s are notorious and indeed I,ll go further they seem to like shell 98 which Ferrari recommends.
You do notice a difference. So that debunks the “ its all from the same refinery “ myth .

I filled up the W12 600 Hp Bentley last week south of Turin at a autosrada filling station all they had was 95 , I’d filled up with 95 previously in Antibes and within a hour decending ( mostly on the brakes so a lot of closed throttle= overfueling ?? ) the St Bernadino pass the CEL came on .

Once in the valley I 1/2 filled it ,in an attempt to dilute the duff 95 with Swiss 98 ready available btw ,and before leaving the forcourt the CEL went out .
It could have been duff Italian 95 ? Or just the fact it does not like 95 Dunno ? Handbook says 98 .

So I would have thought any high powered OB like Verado 350 ,s would be equally sensitive to fuel quality.
 
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Portofino said:
Sometimes in cars particularly high powered cars that spec 98 Ron if you happen to fill up with 95 once or twice consecutively the Check Engine Light - CEL comes on .
A refill even top up 1/2 full with 98 is usually enough for the CEL to go out spontaneously.
Modern Ferrari’s are notorious and indeed I,ll go further they seem to like shell 98 which Ferrari recommends.
You do notice a difference. So that debunks the “ its all from the same refinery “ myth .



I filled up the W12 600 Hp Bentley last week south of Turin at a autosrada filling station all they had was 95 , I’d filled up with 95 previously in Antibes and within a hour decending ( mostly on the brakes so a lot of closed throttle= overfueling ?? ) the St Bernadino pass the CEL came on .

Once in the valley I 1/2 filled it ,in an attempt to dilute the duff 95 with Swiss 98 ready available btw ,and before leaving the forcourt the CEL went out .
It could have been duff Italian 95 ? Or just the fact it does not like 95 Dunno ? Handbook says 98 .

So I would have thought any high powered OB like Verado 350 ,s would be equally sensitive to fuel quality.
Click to expand...

I am glad I only have a Ford mondeo, a Vauxhall vectra and 20 year old outboards.......... So I don't have those problems :)
 
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Lon nan Gruagach said:
Eww, i wish I hadnt read that.
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But that does not mirror reality. The BP Article that is

I know many are going to doubt the following but I own over 40 things with Petrol engines and obviously the fuel is old in many of them. I have never drained any of them. I do indeed top them up with fresh petrol and all generally start ok like Mikes car did.

The items I have with petrol engines are:

Outboards on boats 6 Nr
Petrol Inboards on boats 1 Nr
Jetski 1 No
Petrol Cars 2 Nr
Lawn Mowers 4 Nr
Chain Saws and brush cutters etc 5 Nr
Generator 1 Nr
RC Model Planes with Petrol Engines 20 +
Whoops I forgot Motorbikes 3 Nr
 
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JerryC said:
Take it easy Bigp, you'll be getting the boat owners who also own planes on next, telling us how aviation fuel ages with time.
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They wont beat me. I have over 220 Planes including Jets, Helicopters, War Planes and more besides. Mind you they are all Radio Control :)
 
According to that doc, the RON value of goes up with age so older petrol will be less prone to detonation.

A modern engine won't care if the fuel is slightly more dense either because the ECU and O2 sensor closed loop will just see more unburnt fuel and inject less the balance things out.

If you're running old school carbs this won't be the case tho.
 
Jim@sea said:
You dont get bad Diesel, In December I bought a Land Rover Defender which had been stood for 9 years and after fitting a battery it started third turn of the key, 10 months later its still running on the original diesel, (only used it around the farm)
And a dumper I put into storage 12 years ago started and ran well after fitting a new battery.
My next boat will be a Diesel.
Click to expand...

Aren't there many instances of water in marine diesel fuel tanks causing problems ? Never affected me so far thankfully, but in running petrol engined cars ( plus boats) for 42 years I have never had a single problem caused by "bad" petrol either. Even a lawnmower unused for 5 years but with the old fuel in it started second pull of the cord.

The D4 in my current boat sounds awfully "agricultural" compared to the V8 petrols I had from 2001 to 2015.

I'm thinking along the lines of getting a 300 or 350 hp petrol outboard next
 
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