Hello!
Today I rang an engine servicers and asked if they would look at my engine (i want it balanced and timed). they do work on vws.
The guy said that its not worth tuning original solex carbs because they are always worn out.
is this necessarily true?
He wasnt trying to sell me better ones!
Carb question
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greenfyregirl
- Posts: 302
- Joined: 10th April 2006 - 12:01pm
- Location: cheltenham
I suppose if you knew nothing about them and couldn't be bothered to learn, then that could be your opinion 
They do wear, but it's by no means always the case and even if they are I wouldn't just throw them on the junk heap (if you do then send them my way
).
What happens is that the steel throttle spindles can wear the bores in the softer alloy throttle bodies to the point where air gets sucked in and effects the running (too much air in the mixture).
To fob you off without even looking at them probably indicates more that they can't be bothered, than anything based on fact or experiance.
To tell for yourself, try and move the throttle spindles up and down. They are the spindles that go through the from left to right at the very bottom of the carb (the one at the top is conneceted to the choke flap).
If you can see some movement down there, then they are probably worn.
The good news is that the bodies can be easily removed from the carbs, and it's a straight forward job to get them drilled out and bushed. I've had mine done and also the spindles faced, and now they are better than new and will last longer as the bushes are self lubricating
40 DRLA's are way over the top for a stock engine, and I can't understand why they would suggest you go that route - unless they have a set on the shelf
They'll set you back an arm and a leg to buy, and even choked right down so they'll run you'll get shocking fuel economy with little or no performance gain on their own. There's a bunch of other reasons why they would be unsuitable as well, and they are only really an option if you are looking to build a high performance engine, and only then after you've spent large amounts of money in other areas.
I'd have recommend a Weber 34 ICT kit, but only after looking into repairing what you have first.
Engine balancing requires a complete strip down of the engine, it would be something to look at if you were thinking of a complete rebuild.
Mike.
They do wear, but it's by no means always the case and even if they are I wouldn't just throw them on the junk heap (if you do then send them my way
).What happens is that the steel throttle spindles can wear the bores in the softer alloy throttle bodies to the point where air gets sucked in and effects the running (too much air in the mixture).
To fob you off without even looking at them probably indicates more that they can't be bothered, than anything based on fact or experiance.
To tell for yourself, try and move the throttle spindles up and down. They are the spindles that go through the from left to right at the very bottom of the carb (the one at the top is conneceted to the choke flap).
If you can see some movement down there, then they are probably worn.
The good news is that the bodies can be easily removed from the carbs, and it's a straight forward job to get them drilled out and bushed. I've had mine done and also the spindles faced, and now they are better than new and will last longer as the bushes are self lubricating
40 DRLA's are way over the top for a stock engine, and I can't understand why they would suggest you go that route - unless they have a set on the shelf
They'll set you back an arm and a leg to buy, and even choked right down so they'll run you'll get shocking fuel economy with little or no performance gain on their own. There's a bunch of other reasons why they would be unsuitable as well, and they are only really an option if you are looking to build a high performance engine, and only then after you've spent large amounts of money in other areas.
I'd have recommend a Weber 34 ICT kit, but only after looking into repairing what you have first.
Engine balancing requires a complete strip down of the engine, it would be something to look at if you were thinking of a complete rebuild.
Mike.
Probably carbs balanced rather than engine.
Fully agree - don't go down the 'performance carb' route.
They probably could do with just a decent clean out and readjustment, which is not that hard to do. There is a guy who rebuilds them (assuming he still does them) - Laurie something I think (sorry to be so helpful!).
The Haynes manual is quite good to explain how to do it. Get a can of carb cleaner and have a go! Carb overhaul kits that have some of the bits are not that cheap - probably about £15 per carb. Don't change the needle valve unless it is actually faulty; your old one is probably better than the replacement.
Make sure there are no air leaks in the manifold joints - one of mine was loose at the head and definitely didn't seal well.
On the carbs the two choke pull-down diaphragms needed some awkward repairing with new diaphragms - replacements are hard to find, but I used diaphragms from spare Type 2 carb kits.
Those were the only problems I found. While the throttle butterfly bushes must have some wear, they balanced OK.
For balancing, a 'carbalancer' from Gunson (e-Bay second-hand?) is a great help. If you can get a gas tester for CO levels, that's handy too, but there is a technique to get that close to correct.
Fully agree - don't go down the 'performance carb' route.
They probably could do with just a decent clean out and readjustment, which is not that hard to do. There is a guy who rebuilds them (assuming he still does them) - Laurie something I think (sorry to be so helpful!).
The Haynes manual is quite good to explain how to do it. Get a can of carb cleaner and have a go! Carb overhaul kits that have some of the bits are not that cheap - probably about £15 per carb. Don't change the needle valve unless it is actually faulty; your old one is probably better than the replacement.
Make sure there are no air leaks in the manifold joints - one of mine was loose at the head and definitely didn't seal well.
On the carbs the two choke pull-down diaphragms needed some awkward repairing with new diaphragms - replacements are hard to find, but I used diaphragms from spare Type 2 carb kits.
Those were the only problems I found. While the throttle butterfly bushes must have some wear, they balanced OK.
For balancing, a 'carbalancer' from Gunson (e-Bay second-hand?) is a great help. If you can get a gas tester for CO levels, that's handy too, but there is a technique to get that close to correct.
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purplepeter
- Posts: 2339
- Joined: 8th August 2006 - 4:41pm
- Location: Bath, Avon
As Dave said..Follow the instructions in the Haynes Manual
I found its easier to do the initial settings off the car,despite the fact that they say it can be done in situ,it gives you an op to clean the plugs,and get a better view of rubber hoses on the balance pipe at the same time!
Just follow the instructions,& dont be tempted to miss a stage(voice of experience!)
Dont be afraid of it!-once youve sussed it its easy..youll know if you've stuffed it up as it'll feel 'orrible,but when you get it right its lovely
Halfords sell the gunsons carbalancer for about £12,and youll need some kind of additional adaptor tube to clear the top of the carbs
The Gasure re-bushing seems to be ok,but there were a couple of minor problems afterwards..needed to fit stronger return springs,and there can be probs with the throttle sticking when engine gets hot!
There is incidentally an old mechanics solution to worn spindles..a gentle drop of oil,followed by automotive silicon in a bead round the spindle..silicon helps seal it,& oil prevents the silicon from sticking..works a treat on fraser nash's & cooper-bristols!
I found its easier to do the initial settings off the car,despite the fact that they say it can be done in situ,it gives you an op to clean the plugs,and get a better view of rubber hoses on the balance pipe at the same time!
Just follow the instructions,& dont be tempted to miss a stage(voice of experience!)
Dont be afraid of it!-once youve sussed it its easy..youll know if you've stuffed it up as it'll feel 'orrible,but when you get it right its lovely
Halfords sell the gunsons carbalancer for about £12,and youll need some kind of additional adaptor tube to clear the top of the carbs
The Gasure re-bushing seems to be ok,but there were a couple of minor problems afterwards..needed to fit stronger return springs,and there can be probs with the throttle sticking when engine gets hot!
There is incidentally an old mechanics solution to worn spindles..a gentle drop of oil,followed by automotive silicon in a bead round the spindle..silicon helps seal it,& oil prevents the silicon from sticking..works a treat on fraser nash's & cooper-bristols!
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greenfyregirl
- Posts: 302
- Joined: 10th April 2006 - 12:01pm
- Location: cheltenham
