How easy is it to refurb carbs?
Discussion
Over the winter I'm thinking of buying this book...
... and a refurb kit...
... and having a bash at stripping, cleaning and replacing all the bits inside my carbs. Then replacing any of the bearings, linkages that look worn etc.
Before the MOT at the start of the spring I intend to get the Cambelt done and have a rolling road tune so even if I upset them, they should be in good condition for an expert to set them up.
Is it pretty straight forward, or is this going to end in disaster??
... and a refurb kit...
... and having a bash at stripping, cleaning and replacing all the bits inside my carbs. Then replacing any of the bearings, linkages that look worn etc.
Before the MOT at the start of the spring I intend to get the Cambelt done and have a rolling road tune so even if I upset them, they should be in good condition for an expert to set them up.
Is it pretty straight forward, or is this going to end in disaster??
A cheap ultrasonic cleaner from Aldi or similar will be a boon. I bought 4 of them for £15 each when they last had them in stock for cleaning fuel injectors and other small parts. They will rip off any deposits of carbon or scale without damaging the underlying metal. Clean the good bits, replace anything with wear and it's not a very complicated job.
I think the last two people are being a bit disingenuous.
Carbs are very difficult things to deal with. They are after all doing the same job as an engine management system, but with mechanicals.
Of the number I have stripped, clean and replaced, about half were no problem. Of the half left, half did not work when back on the car and had to be taken apart to find out why. This requires quite a lot of individual testing, and setting up before they were performing again, and the rest went through the entire process of on/off/on/off, but setting them up was always a compromise, and was never very satified that they were performing properly, although they did perfomr adequately.
Don't approach this with the idea that carbs are easy, and don't beleive anyone who tells you they've never had a problem. After all when carbs were mainstream, it was always the most senior mechanic in a garage who's job was to fiddle with them, and someone good on carbs was probably the highest paid mechanic on the racetrack.
Carbs are very difficult things to deal with. They are after all doing the same job as an engine management system, but with mechanicals.
Of the number I have stripped, clean and replaced, about half were no problem. Of the half left, half did not work when back on the car and had to be taken apart to find out why. This requires quite a lot of individual testing, and setting up before they were performing again, and the rest went through the entire process of on/off/on/off, but setting them up was always a compromise, and was never very satified that they were performing properly, although they did perfomr adequately.
Don't approach this with the idea that carbs are easy, and don't beleive anyone who tells you they've never had a problem. After all when carbs were mainstream, it was always the most senior mechanic in a garage who's job was to fiddle with them, and someone good on carbs was probably the highest paid mechanic on the racetrack.
julian64 said:
I think the last two people are being a bit disingenuous.
Carbs are very difficult things to deal with.
For the hard of thinking maybe. For anyone with the basic mechanical skills required to assemble Ikea furniture they are not a problem. Have you ever considered your issues with rebuilding them properly doesn't lie in the carbs themselves?Carbs are very difficult things to deal with.
Carbs are EASY!
Clean them carefully. Only small bits of debris can block a jet entirely.
Setting the carbs up again seems to be the hardest bit, as most people (including "carb specialists") don't know what the screws do or why they are turning them. But essentially you want to adjust each idle screw until each cylinder is doing as much work as it can, but also an equal amount to all the other cylinders.
Taking off each plug lead should cause an equal rev drop.
Avoid the temptation to fiddle with the air bypass, as these are set at the factory and rarely (never) need to be adjusted. Fix the problems with worn spindles and butterflies rather than trying to compensate by ruining the factory calibration.
Clean them carefully. Only small bits of debris can block a jet entirely.
Setting the carbs up again seems to be the hardest bit, as most people (including "carb specialists") don't know what the screws do or why they are turning them. But essentially you want to adjust each idle screw until each cylinder is doing as much work as it can, but also an equal amount to all the other cylinders.
Taking off each plug lead should cause an equal rev drop.
Avoid the temptation to fiddle with the air bypass, as these are set at the factory and rarely (never) need to be adjusted. Fix the problems with worn spindles and butterflies rather than trying to compensate by ruining the factory calibration.
I've found a number of ultrasonic/vapour blasting places that seem reasonably priced, and the carbs look pretty good after.
The car will be SORN, so I have plenty of time to get it right.
So here's a question - do most components screw home, or does everything require adjustment?
I'm good with the idle mixture screws and balancing the carbs but have never done anything with Jets/Emulsion tubes etc...
Look out for a thread in a months time asking what went wrong.
The car will be SORN, so I have plenty of time to get it right.
So here's a question - do most components screw home, or does everything require adjustment?
I'm good with the idle mixture screws and balancing the carbs but have never done anything with Jets/Emulsion tubes etc...
Look out for a thread in a months time asking what went wrong.
Edited by Glade on Friday 16th September 13:34
If I could give you any advice before the 'Its easy' team come back to question my interlect again. I would say record carefully the current working positions of all the jets. Although there will be a setup proceedure, it is always useful to know if the problem lies with the setup or the mechanics of the carb. So a quick check with the old positions to see if you have a working system first.
Never feel tempted to clean the holes on any of the jets with anything other than the bath, and an air supply, lastly your best tests would involve air pressurising the carb on a flat bench with the top sealed to make sure no air can bypass the carb in any way.
Never feel tempted to clean the holes on any of the jets with anything other than the bath, and an air supply, lastly your best tests would involve air pressurising the carb on a flat bench with the top sealed to make sure no air can bypass the carb in any way.
I've just refurbished four DRLA48 Dellotos on my Tuscan Racer. The trickiest part was setting the float levels. Instructions to do this are on the Eurocarb website. Just be ultra methodical, clean, and don't get any bits mixed up. Also be careful when removing the pump jets as they incorporate little springs which have a habit of twanging out. A couple of tins of carb cleaner and a compressed air supply is very useful but be careful with the carb cleaner its a bit dodgy.
Did all mine in one day on the dining room table. Obviously I made sure the wife wasn't home at the time
Did all mine in one day on the dining room table. Obviously I made sure the wife wasn't home at the time
Mr Subtle said:
And dont be tempted to poke pins etc thru the jets, itll enlarge them and theyll meter incorrectly.
That's a load of nonsense too. Try machining metal with the side of a smooth hard object like a pin. You'll be there a good long while without much happening. Now a file, or a drill bit, anything with cutting edges ought to do the trick but wire, pins or anything else without cutting edges won't make a blind bit of difference to the size of the hole through a jet. Whoever started this stupid old wives tale probably did it for a bet to see how many of the hard of thinking would repeat it and I guess they won the bet.Pumaracing said:
That's a load of nonsense too. Try machining metal with the side of a smooth hard object like a pin. You'll be there a good long while without much happening. Now a file, or a drill bit, anything with cutting edges ought to do the trick but wire, pins or anything else without cutting edges won't make a blind bit of difference to the size of the hole through a jet. Whoever started this stupid old wives tale probably did it for a bet to see how many of the hard of thinking would repeat it and I guess they won the bet.
Talked yourself out of another sale there id say.....what a pleasant man.Well they do say I'm a pheasant plucker. There's a simple rule on here. If you don't want to get slapped down then don't post rubbish you've heard in the pub and not bothered to think about to decide if it's true or not. If you think you can enlarge a carb jet with a pin then I'll make you a simple bet. You get locked up in a dungeon with a brass carb jet and a steel pin. The pin is sized so it fits right through the jet so you can't just hammer it in and swage the jet out. You have to enlarge the jet to the next size up which is 0.05mm bigger being the common size increment for Weber and Dellorto jets and the smallest increase which would actually show a difference on a dyno test.
When you've done that you get food and water. If you can't you die of dehydration assuming you have fat reserves capable of sustaining your life longer than you can live without water. There are certainly strategies you could use. You could make an abrasive slurry from blood from your raw and bleeding fingers and dust from the floor and use that to coat the pin and use it as a lap. Eventually it might remove some brass. If you succeed before you die I pay you 50p. I think I can afford that.
When you've done that you get food and water. If you can't you die of dehydration assuming you have fat reserves capable of sustaining your life longer than you can live without water. There are certainly strategies you could use. You could make an abrasive slurry from blood from your raw and bleeding fingers and dust from the floor and use that to coat the pin and use it as a lap. Eventually it might remove some brass. If you succeed before you die I pay you 50p. I think I can afford that.
Pumaracing said:
Well they do say I'm a pheasant plucker. There's a simple rule on here. If you don't want to get slapped down then don't post rubbish you've heard in the pub and not bothered to think about to decide if it's true or not. If you think you can enlarge a carb jet with a pin then I'll make you a simple bet. You get locked up in a dungeon with a brass carb jet and a steel pin. The pin is sized so it fits right through the jet so you can't just hammer it in and swage the jet out. You have to enlarge the jet to the next size up which is 0.05mm bigger being the common size increment for Weber and Dellorto jets and the smallest increase which would actually show a difference on a dyno test.
When you've done that you get food and water. If you can't you die of dehydration assuming you have fat reserves capable of sustaining your life longer than you can live without water. There are certainly strategies you could use. You could make an abrasive slurry from blood from your raw and bleeding fingers and dust from the floor and use that to coat the pin and use it as a lap. Eventually it might remove some brass. If you succeed before you die I pay you 50p. I think I can afford that.
Manners cost nothing my friend, youve absolutely no excuse for acting like a pig unless you want people to treat you like one.When you've done that you get food and water. If you can't you die of dehydration assuming you have fat reserves capable of sustaining your life longer than you can live without water. There are certainly strategies you could use. You could make an abrasive slurry from blood from your raw and bleeding fingers and dust from the floor and use that to coat the pin and use it as a lap. Eventually it might remove some brass. If you succeed before you die I pay you 50p. I think I can afford that.
As for "slapping" people down, why? No need to be a prick about it, if someones wrong then theres plenty of ways to do it without resorting to being a gold plated peenarse, unless you just enjoy the conflict you create.
To the O/p dont stick pins into jets, they can get stuck, they can score the edges, the can enlarge the jets.
weber carbs service/overhaul manual -isbn 1850100616 page 24, para 14.
"Note Never use wire to clean a jet"
Dear god... I ordered the book after a few Ciders last night - about 18.15.
It's just been delivered, even though I took their standard delivery service!!!
Kudos to the ebay seller - Cheapest price on ebay too - I can highly recommend these guys if anyone is after the book.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&am...
Speedy Hen http://myworld.ebay.co.uk/speedyhenuk/?_trksid=p43...
Time to start destroying my carbs!
It's just been delivered, even though I took their standard delivery service!!!
Kudos to the ebay seller - Cheapest price on ebay too - I can highly recommend these guys if anyone is after the book.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&am...
Speedy Hen http://myworld.ebay.co.uk/speedyhenuk/?_trksid=p43...
Time to start destroying my carbs!
Glade said:
Dear god... I ordered the book after a few Ciders last night - about 18.15.
It's just been delivered, even though I took their standard delivery service!!!
Kudos to the ebay seller - Cheapest price on ebay too - I can highly recommend these guys if anyone is after the book.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&am...
Speedy Hen http://myworld.ebay.co.uk/speedyhenuk/?_trksid=p43...
Time to start destroying my carbs!
Good service indeed! It's just been delivered, even though I took their standard delivery service!!!
Kudos to the ebay seller - Cheapest price on ebay too - I can highly recommend these guys if anyone is after the book.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&am...
Speedy Hen http://myworld.ebay.co.uk/speedyhenuk/?_trksid=p43...
Time to start destroying my carbs!
Answered the phone/email in a timely manner and sent your items out without even insulting you.
Some could learn from that.
Mr Subtle said:
Manners cost nothing my friend, youve absolutely no excuse for acting like a pig unless you want people to treat you like one.
As for "slapping" people down, why? No need to be a prick about it, if someones wrong then theres plenty of ways to do it without resorting to being a gold plated peenarse, unless you just enjoy the conflict you create.
To the O/p dont stick pins into jets, they can get stuck, they can score the edges, the can enlarge the jets.
weber carbs service/overhaul manual -isbn 1850100616 page 24, para 14.
"Note Never use wire to clean a jet"
The same manual probably says wear ear, eye and hand protection before starting work as petrol will kill you, or to wear a tin foil hat in case your mobile melts your brain. It'll tell you to not do all the things you HAVE to do to do any work. So ignore the book - you CANNOT damage jets with a pin, wire or anything like that. I suppose you COULD get a pin stuck, but you'd have to be a world class moron to manage that. Scoring the edges will not make any measurable difference to the metering of the fuel, and even if did it might actually improve it.As for "slapping" people down, why? No need to be a prick about it, if someones wrong then theres plenty of ways to do it without resorting to being a gold plated peenarse, unless you just enjoy the conflict you create.
To the O/p dont stick pins into jets, they can get stuck, they can score the edges, the can enlarge the jets.
weber carbs service/overhaul manual -isbn 1850100616 page 24, para 14.
"Note Never use wire to clean a jet"
There are some people that deserve being treated politely. Then there are people who don't engage brain before repeating what a mate told them.
Mr Subtle said:
Manners cost nothing my friend, youve absolutely no excuse for acting like a pig unless you want people to treat you like one.
As for "slapping" people down, why? No need to be a prick about it, if someones wrong then theres plenty of ways to do it without resorting to being a gold plated peenarse, unless you just enjoy the conflict you create.
To the O/p dont stick pins into jets, they can get stuck, they can score the edges, the can enlarge the jets.
weber carbs service/overhaul manual -isbn 1850100616 page 24, para 14.
"Note Never use wire to clean a jet"
So did you take the bet? My money is on pumaracing for this one...As for "slapping" people down, why? No need to be a prick about it, if someones wrong then theres plenty of ways to do it without resorting to being a gold plated peenarse, unless you just enjoy the conflict you create.
To the O/p dont stick pins into jets, they can get stuck, they can score the edges, the can enlarge the jets.
weber carbs service/overhaul manual -isbn 1850100616 page 24, para 14.
"Note Never use wire to clean a jet"
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