Petrol waxing.

Gramaisc

Forum O. G.
I've got a bit of an issue with wax deposits in the float bowl of a petrol mower. Twice this year it's blocked the main jet and left it only able to run with the choke on. I cleared it out again today and got about a pea-sized amount of wax out of it.

I suppose that most vehicles are injection these days and wouldn't have much trouble from a little bit of soft wax, but small gravity-fed carburettors are another matter.

Any ideas?
 

Gramaisc

Forum O. G.
Mmm, I opened the reserve mower, just out of interest, and found the float bowl with even more wax in it.


It bears a strong resemblance to the stuff that I'm still getting out of my ear after the worst cold in recorded history...
 

Laurie61

Well-Known Forumite
Perhaps try the higher grade petrol, the type with detergents in to keep engine internals clean. The amount used in a lawn mower would not cost a lot more to use than standard petrol.
 

Gramaisc

Forum O. G.
Perhaps try the higher grade petrol, the type with detergents in to keep engine internals clean. The amount used in a lawn mower would not cost a lot more to use than standard petrol.
It may come to that, but the sheer quantity of the deposits is quite bizarre. It only seems to occur in the float bowls - everything else is totally clear. It's as though there's some sort of reaction with the cast alloy there. There's a visible fuel filter before the float and there's none in there. Most of the rest of the fuel system is plastic or rubber.

Now that I know what's going on, it's not the end of the world and the dismantling of the carbs is easy enough when you finally find all the tricks...

They are Kawasaki motors and use bugger all, it will be a while before the current supply dwindles.
 

Gramaisc

Forum O. G.
Ran one of the mowers successfully, without any further trouble so far - maybe just one more cut this year now.

DSC_0937.JPG


We'll see what they're like after the winter.
 

Gramaisc

Forum O. G.
The waxing issue continues - it's just stopped on me now for the first time this year, I think (maybe the second) - cleared again and running OK once more.

The engines that it occurs in are identical Kawasaki devices - there is also a smaller Honda engine that uses the same fuel and doesn't display the problem at all.

It seems to be some sort of reaction that occurs in the float bowl.
 

Studio Tan

Well-Known Forumite
Just a thought but are there any parts of the fuel system that are synthetic (float bowl, pipework etc) that are decomposing / being attacked by the fuel? Are the engines run dry at the end of the seaon so no stale fuel left in?
 

Gramaisc

Forum O. G.
The float bowls are a Mazak-type alloy, with brass jets, etc - the floats are plastic, but seem quite sound and their surfaces are still smooth - the tank is plastic, with (I presume) a synthetic rubber hose, but they are 'before' a clear filter bowl, which gets no wax in - it all does seem to form in the float bowl and adhere to the alloy parts. Eventually, a bit dislodges and blocks the jet.

I might still have a little jar of Pet-Seal somewhere, I might coat the bowl inner surfaces - maybe just one and see what happens.

As for draining it, it still happens when being used weekly after it's been thoroughly cleaned.
 

Studio Tan

Well-Known Forumite
Mystifying ! Could it be a build up of ‘varnish’ upstream from the carburettor in the fuel tank itself. I saw something on the web about someone having similar problems with an outboard motor and describing ‘waxy’ deposits clogging the fuel tank.

Is it worth trying a petrol additive ?
 

Gramaisc

Forum O. G.
Mystifying ! Could it be a build up of ‘varnish’ upstream from the carburettor in the fuel tank itself. I saw something on the web about someone having similar problems with an outboard motor and describing ‘waxy’ deposits clogging the fuel tank.

Is it worth trying a petrol additive ?
If it's happening in the tank, then I would expect to find some in the mesh filter where the fuel tap is - and that is clear...

A look inside the tank shows nothing, either.
 

Studio Tan

Well-Known Forumite
Looks like 'Petsealing' is the only option left !
Or could the Kawasaki Tech. Dept. offer any advice?
If you do use Petseal I'd be interested to know the outcome.
 

Gramaisc

Forum O. G.
Looks like 'Petsealing' is the only option left !
Or could the Kawasaki Tech. Dept. offer any advice?
If you do use Petseal I'd be interested to know the outcome.
I have used it before, with reasonable success, on a rust-holed petrol tank. Two goes were necessary for that as I remember, but this would just be a surface coating, not filling any actual leakage points.

I just have to find it now - if it is still there...


It could just be the actual fuel that is in use, I suppose, the stuff that is in there now will be run dry, then the next batch will be from a different garage chain (possibly of a different origin). Years ago, when I had a 'proper job', we had a corrosion issue with an aircraft hydraulic fluid. Originally, it all came from a German refinery and was OK for twenty years, then they started producing it, to the same specification, from a UK refinery. Although they both were allegedly to exactly the same specifications, the UK stuff was rubbish, you could actually feel the difference with your fingers and a nail hanging in a jar of it would be rusty within a week. Under duress, they agreed to supply us with stuff from Germany, but they never really accepted the truth of what was going on. We carried on with the high-tech 'nail in a coffee jar' test, just in case...
 

Cue

Well-Known Forumite
I admire your persistence

I would have given up and picked up a battery mower by now.
 

Cue

Well-Known Forumite
You need to take care. They can be quite heavy, so you could easily put your back out.

I'm not sure if we're just not talking about the same thing or you're making a joke I don't understand the reference of - with you I can never be sure.
 

proactive

Enjoying a drop of red.
I'm not sure if we're just not talking about the same thing or you're making a joke I don't understand the reference of - with you I can never be sure.
I assure you I was being 100% serious.

I suppose if the battery is flat it might be a little lighter to pick up.
 

Gramaisc

Forum O. G.
As pointed out here, I used a rechargeable mower over fifty years ago, however, the modern ones seem to be mostly rotary jobs or cylinders that are more suited to the modern-day English size of garden.

Webb-Battery-Mower-IMGWebb010.jpg


I believe that it was one of these Webbs that I used back then.


The possibility of electrifying the current Punches may come along in the future, I suppose.

574051e64d225e56159bc02c


It would just be a matter of sourcing a suitable motor/battery combination and mounting it onto the end of the drive-shaft.
 
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