Clogged carbs / can i give it wellie to clear it?

rustybouy

rustybouy

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Hi all, quick Q, if my outboard carbouretta ( i think thats how you spell it) is clogged up,which i believe it is, is the only way to rectify this to take it apart and clean it? Im not keen on tackling the job and wondered if just by running the engine i would be able to clear the gunked up nozzles. i can get the engine running,however i really need to open up the throttle to do this which is tricky because i need to keep the gear from engaging, the throttle has a start position of about a quarter turn which is not enough to get her started,to get the throttle to open more i need to be in gear, it's tricky :rolleyes: I've tried altering the idle mix etc,I've got the right plugs, im sure i can get the gear linkage disconnected so i can run high revs without being in gear, I've sprayed cleaner in aswell, what do you think ? will the carb clear if i run it on and off for a few days or weeks giving it a good blast?

Thanks

Pete
 
I would take the carburetor apart and spray the jets through with WD40, using the little pipe supplied with the tin. I've done it with loads of bike carbs. If you really don't fancy dismantling it, STP carb cleaner is worth a try. I've never used the STP carb cleaner, but their fuel injector cleaner works a treat.
 
rustybouy said:
Hi all, quick Q, if my outboard carbouretta ( i think thats how you spell it) is clogged up,which i believe it is, is the only way to rectify this to take it apart and clean it? Im not keen on tackling the job and wondered if just by running the engine i would be able to clear the gunked up nozzles. i can get the engine running,however i really need to open up the throttle to do this which is tricky because i need to keep the gear from engaging, the throttle has a start position of about a quarter turn which is not enough to get her started,to get the throttle to open more i need to be in gear, it's tricky :rolleyes: I've tried altering the idle mix etc,I've got the right plugs, im sure i can get the gear linkage disconnected so i can run high revs without being in gear, I've sprayed cleaner in aswell, what do you think ? will the carb clear if i run it on and off for a few days or weeks giving it a good blast?

Thanks

Pete
Click to expand...

Very unlikely to clear on its own.

Spraying carb cleaner in via the air intake just wont get to the parts it needs to to do any good. Maybe worth adding some of the STP or similar stuff to the fuel
Ultimately I expect you will have to take it to bits and clean the jets and all the passage ways. Soaking the jets etc in carb cleaner might then help. Blow everything through with compressed air if you can. I like to poke a soft copper wire through jets to clean them. Soft copper 'cos it wont damage them.

You are sure its blocked jets that are the cause of your problem .... it will run partially choked ?

BTW the English spelling is carburettor
 
elton said:
I would take the carburetor apart and spray the jets through with WD40, using the little pipe supplied with the tin. I've done it with loads of bike carbs. If you really don't fancy dismantling it, STP carb cleaner is worth a try. I've never used the STP carb cleaner, but their fuel injector cleaner works a treat.
Click to expand...

Unfortunatly they will need to be cleaned. running wont do it even with cleaner in fuel. the problem is the idle jets get blocked by gunk or a varnish buid up as fuel in carb evaporates.
A liberal use of a spray carb cleaner may help for a while. you probabaly find moter won't idle. float also sticks.
Most have carb kits avalable from manufaturer.
probabaly a couple of hours of mechanics time to clean and service at begining of season may cost about 150 to 200.
 
I kinda thought that would be the case,bugger.

I'm ok with big stuff, i don't like fiddly parts!, if i take off this carb there's a chance i'll end up taking all the bits to someone to re-assemble the thing,springs flying everywhere, i think i'll bite the bullet and give it a go, the engine only cost £240 quid, so if it all goes wrong i'm not losing that much, i don't want it lying in bits taking up room in the garage if i cant fix it, nothing ventured....

thanks lads

Pete
 
British spelling is carburetter not the yank version which is carburettor
you didn't say which engine.
You will need to take it off and use compressed air to clean the jets do not poke any thing through the jets or you risk damage. I use spray gun cleaning thinners to clean carburetters before stripping, the spray stuff is pretty weak.

On the odd occasion when I've sold a new carburetter the internal parts can have corrosion re the zinc and copper / brass acting like a battery, it does this because of condensation. This normally clears once petrol comes into contact with it. There is always the chance your's might
whose to say

cheers
Mick
 
No - the carb is at the suck end not the blow end so you wont get enough pressure to clear the gunge. Go to your local motor factors and get a can of carb cleaner which is a solvent good at shifting varnishes and gums. Alternatively try your local big mower place - they have small engines with small carbs and easily blocked jets so they often have ultrasonic cleaning machines.
 
Take the carb off and soak the whole thing in pot of cellulose thinners making sure it penetrates everywhere and leave for a day or two. Use airline to blow dry then repeat the process again. The gum will have dissolved by then. A 5ltr can of cellulose thinners from your local motorfactor is cheap and usefull for many cleaning jobs.

Put about 5% cellulose thinners into the petrol for the first half tank full too, that will clear any gum or glazing on the cylinder walls and piston rings.
 
If you are not confident about this job, remove and take to a motor cycle repair shop and ask for it to be stripped and cleaned
 
mtb said:
British spelling is carburetter not the yank version which is carburettor

Mick
Click to expand...

According to the OED carburettor is the UK English spelling . Carburetter is an alternative UK spelling. Carburetor, carbureter and carburator are US spellings

BTW did you know that you can access the OED and other Oxford reference books, including the Oxford Companion to Ships and the Sea, by using your library card number. ( I also found SWMBO's railcard number worked )
 
SAMYL said:
Take the carb off and soak the whole thing in pot of cellulose thinners making sure it penetrates everywhere and leave for a day or two. Use airline to blow dry then repeat the process again. The gum will have dissolved by then. A 5ltr can of cellulose thinners from your local motorfactor is cheap and usefull for many cleaning jobs.

Put about 5% cellulose thinners into the petrol for the first half tank full too, that will clear any gum or glazing on the cylinder walls and piston rings.
Click to expand...

WHOA! We have not been told what carb this is .. Some have plastic parts.. Dunking the whole thing in cellulose thinners might reduce it to a worthless sticky mess
 
Many small carbs have internal galleries which you cannot get to however much stripping down you do. Not boaty but essentially the same, I had trouble with a carb on a Honda mower, I removed it and took it to a place that repairs same plus outboard engines. They have an ultrasonic (I think) machine/tank which breaks down all the foreign bodies hidden away that you cannot get to. So based on the fact you are not happy doing a strip down, plus the possibility of disappointment with the result, I would join others in suggesting a lawn mower/motorcycle/outboard specialist to do the cleaning.
 
Yes - use carb cleaner, made for the job and quite cheap. And dont bother with a motorcycle shop - most bikes have been fuel injuection for yoears but in any case the carbs they use are for much bigger engines, have much bigger jets and can be much more easily cleaned. Try mower shops as suggested - their engines are the same size as small out boards.
 
that sounds like a plan pampas, its a 7.5 1986 mercury outboard, i did download a maintenance manual for it but it's not very detailed,not for a job like this anyway, i'll enquire about the price of someone else doing it, i dont have compressed air available to blow through even if i did take it apart, im torn really

should've bought a 4 stroke newish engine,i need to lift this one on and off myself though and needed the 2 stroke for its weight

i could claim it on my insurance if anyone would like to steal it?? :)


joking.

Pete
 
rustybouy said:
that sounds like a plan pampas, its a 7.5 1986 mercury outboard, i did download a maintenance manual for it but it's not very detailed,not for a job like this anyway, i'll enquire about the price of someone else doing it, i dont have compressed air available to blow through even if i did take it apart, im torn really

should've bought a 4 stroke newish engine,i need to lift this one on and off myself though and needed the 2 stroke for its weight

i could claim it on my insurance if anyone would like to steal it?? :)


joking.

Pete
Click to expand...

The owners manual should be available for download from the download centre at Brunswick marine http://download.brunswick-marine.com/download/main;jsessionid=105vjo07c1lcd?type=corp but I do not think there will be any info on stripping and cleaning the carb

You may find a more useful manual at http://boatinfo.no/lib/library.html but I cannot see a 7.5 hp mentioned but you may find the same carb on a 6 hp or 8hp

exploded parts diagrams at http://www.boats.net/parts/search/Merc2/Mercury/7.5/parts.html may be useful


Take care when dismantling to note how it all went together. Work where you cannot lose small parts if you drop them.. In a tray if possible. Check each bit for little joint washers O rings etc as you go.
 
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VicS said:
According to the OED carburettor is the UK English spelling . Carburetter is an alternative UK spelling. Carburetor, carbureter and carburator are US spellings

BTW did you know that you can access the OED and other Oxford reference books, including the Oxford Companion to Ships and the Sea, by using your library card number. ( I also found SWMBO's railcard number worked )
Click to expand...

British companys that made carburetters all use the correct english spelling zenith solex stromber SU all of course use the correct term.
I at times have to use the american version re ebay but that does not make it right
I deal in vintage and classic carburetters for a living I dont read it off the net !
mick
 
VicS said:
WHOA! We have not been told what carb this is .. Some have plastic parts.. Dunking the whole thing in cellulose thinners might reduce it to a worthless sticky mess
Click to expand...

Fair point. Perhaps better to strip plastic bits off first.

But it does work very well though.
 
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