Carb cleaner petrol additive anyone??

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sparkie

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Hi all, just restarted the Tohatsu after the winter layoff, as usual the pilot jet had fouled up over the winter, and despite soaking in thinners and poking with a bit of fuse wire it's still not brill. Fortunately I always carry a new spare......

Anyway, it struck me that the best solution would be to prevent the problem occurring in the first place. Has anyone ever sourced and used an additive to prevent the gumming problems that unleaded "petrol" seems to cause these days??

Sparkie
 
Is it 4 or 2 stroke? If 2 stroke the best thing is to turn off the fuel after running and allow to run itself dry. This stops the 2 stroke oil gumming up the jets.
 
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Hi, it's a four stoke. I always run dry when leaving it for the winter, but it still gums up, and will also do it even when in regular(ish) use. Many people are experiencing the same problem I believe.

Cheers

Sparkie
 
sparkie said:
Hi all, just restarted the Tohatsu after the winter layoff, as usual the pilot jet had fouled up over the winter, and despite soaking in thinners and poking with a bit of fuse wire it's still not brill. Fortunately I always carry a new spare......

Anyway, it struck me that the best solution would be to prevent the problem occurring in the first place. Has anyone ever sourced and used an additive to prevent the gumming problems that unleaded "petrol" seems to cause these days??

Sparkie
Click to expand...

When I worked in a lab manyyears ago we did some work on carb cleaners while working on motorised horticultural spraying machines.
We found white spirit was just as effective and readily dissolved the gum residues - worth a try. You could also try a shot of Redex in the fuel?
 
Use a 'fogging' spray? Sprayed into air intake I believe until engine stalls.

Never used them myself, so only mentioning for you to investigate or others to comment upon.
 
Most people fail to realize that running an engine dry does not clear the petrol out of the carb. The float bowl will still be nearly full and if left there it will gum up the jets.
To clear that you have to drain the carb by undoing the small screw at the base of the float bowl, if it has one, or by inverting the engine to drain it by literally pouring the petrol out of the carb.
Be carefull inverting the engine that any retained water does not run back up the exhaust into the cylinder(s). Pull the engine over a few times to clear it.
 
SAMYL said:
Most people fail to realize that running an engine dry does not clear the petrol out of the carb. The float bowl will still be nearly full and if left there it will gum up the jets.
To clear that you have to drain the carb by undoing the small screw at the base of the float bowl, if it has one, or by inverting the engine to drain it by literally pouring the petrol out of the carb.
Be carefull inverting the engine that any retained water does not run back up the exhaust into the cylinder(s). Pull the engine over a few times to clear it.
Click to expand...

Yes I've often thought that might be the case, and explains why it still gums up over the winter. I have a drain screw but a bit difficult to do when on the boat and leaving just for a few weeks.

Cheers

Sparkie
 
My father who ,despite having fought WWll as a fitter at RAF St Athan, had little mechanical skill and absolutely no marine ones but he knew some theory and swore by Redex.
He toyed around with boats in the 1950's and bought a new Johnson 10hp. Several of his friends had them and complained about the carburetters gumming up. Father's did not because befiore shutting down for the Winter he squirted Redex into the carb intake. He lost interest in boats and the Johnson stood in the corner of his shed .
About 10 or 11 years later I found it. Put it up on a fence.Filled the tank and pulled the string...second pull and it roared into life.
That convinced me that on this matter the Old Boy knew what he was talking about....try Redex.
 
Thanks Croc, yes others have suggested that, and I did use it many years ago in motorbikes. It's certainly readily available and cheap enough so I think at the moment it's looking like the first thing to try.

Cheers

Sparkie
 
Be very carful inverting 4-stroke engines or even storing them on their side; the lubrication oil can flow into the combustion chamber.

Individual engies vary, but for this reason there should be a recommended stowage position in the handbook, which is unlikely to include 180 degrees !

If oil does flow into the chamber , and the engine is turned over with the starter chord, a hydraulic lock and /or expensive damage like bent con-rods can result.

I'd suggest most carb's are usually very easy to remove, which would be a safer and more thorough method of draining if there isn't a drain plug.
 
I use Briggs and Stratton's petrol additive if leaving my lawn mower, chainsaw, strimmer, hover mower, and outboard out of use for more than a few weeks. All the machine's start first time after many months out of use and have done for years. The additive is available at any lawnmower service centre. I've heard some say that the additive is bad for engines, but I've never had a problem and my local lawn mower man swears by the stuff. Hope this helps.
 
Wit a load a rubbish I just read !!!
if you run the carb dry , it only takes the fuel from the float bowl , so uses it all up and the carb is run dry!, anything you spray down the carb will not go near the float bowl, or main jet , and stop it gumming up. were did all this mince come from.
 
CLP said:
I use Briggs and Stratton's petrol additive if leaving my lawn mower, chainsaw, strimmer, hover mower, and outboard out of use for more than a few weeks. All the machine's start first time after many months out of use and have done for years. The additive is available at any lawnmower service centre. I've heard some say that the additive is bad for engines, but I've never had a problem and my local lawn mower man swears by the stuff. Hope this helps.
Click to expand...

Thanks for that- yes, never thought about lawn mowers. I've never heard of this additive, so I'll make a point of finding out. Actually my mower (also B & S engine) starts a lot more reliably than the Tohatsu- I've often wondered why this should be so. Also strangely I've never had a problem with jets etc in the mower, despite using any old stale fuel/left over 2stroke etc- maybe the Yanks are just better at this sort of thing than the Japanese.......

Cheers

Sparkie
 
sparkie said:
.... Also strangely I've never had a problem with jets etc in the mower, despite using any old stale fuel/left over 2stroke etc- maybe the Yanks are just better at this sort of thing than the Japanese.......
Click to expand...

Me neither. My small strimmer is also brilliant, pretty sure that will be Chinese.

On the subject of outboards, the worst gummed up carb I got was due to leaving it in a baking hot car boot for a few weeks, beware.
 
sparkie said:
Anyway, it struck me that the best solution would be to prevent the problem occurring in the first place. Has anyone ever sourced and used an additive to prevent the gumming problems that unleaded "petrol" seems to cause these days??

Sparkie
Click to expand...

Best way is to run the engine dry before storing and to empty the tank completely. As for cleaning jets, use carb cleaner. Works better than thinners.

I doubt that anything will stop the lighter contents of petrol flashing off during storage leaving the varnishes behind but I have not tried the additives.
 
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