solex carb/adjustments? - Page 2

Crazy Harry · 09-09-2007

Tomking,

I'm still going through all the post in the forum. I had to print them and am half through the stack of paper! I agree that the screwdriver slot is not the problem, that photo was more to show the jet's size marking. My concern with the idle air jet is the deformed holes on the barrel, I'm sure they're supposed to be round and not squashed like the photo. The little hole in the end looks OK and the area of the barrel holes is probably larger than the real orifice. I believe it still seats properly. I put some ink on the sealing surface, reinstalled and then removed the jet, all ink was gone. Prior to the rebuild I could get the engine to run quite smoothly by playing with the position of this jet, even though this is not a legitimate adjustment.

BQS4,

If you can 'part' with the leaf spring that holds the float hinge and the idle air jet, size g47.5 that would be great

. Let me know what I owe you! I've sent a PM with my address.

All suggestions and help are more than welcome! Thanks,

Harold.

BQS4 · 09-09-2007

Ok;
Are these what you're looking for? Also as you can see, the "jet" has been badly damaged when you compare it to the one I have here.

Crazy Harry · 09-09-2007

Gene,

That's exactly what I'm looking for

! Hope I didn't keep you up too late tonight

!

I hope they solve my troubles.

Thanks,

Harold.

BQS4 · 09-09-2007

Nah, I keep an almost complete inventory in the back of my Sportwagon, ask anyone who has seen my Wagon at Carlisle!

Just kidding, It may be a day or so before I can get by the Post Office, as we're up to our ears in work, but, hang on, help's on the way!!

Crazy Harry · 09-09-2007

That's great Gene, I can wait knowing help is on its way! Thanks again,

Harold.

gr_diver · 09-10-2007

With so much deformation on the idle jet I would be concerned about the condition of the threads where the jet gets screwed in. I think it would be easier to strip the threads than bend the jet that much. The carb's body is a soft alloy, so check that the threads are in good condition

The damaged idle jet is a sure cause for headache! Those bent holes are the metering holes for the air, that gets in from a tiny hole at the air-horn. The fuel enters the jet from the tiny hole at the small end. So the idle/progression mixture is not properly aerated.

But I don't think it is related to the interminent dripping of fuel from the primary main jet, unless...

...Unless the dripping that you describe happens with the engine idling high (as you describe you have to set it now). If the replacement jet solves the high idle (I bet it will), and then the dripping continues verify that the diaphragm in the power valve is in good condition. They tend to get hard and jam the piston in the open position...

Crazy Harry · 09-10-2007

gr_driver: The dripping is at high idle and seems to be at constant driving speed as well. It was at low idle before the rebuild as well. I did notice that backing out the idle jet (I guess it let some more air in around the threads) cleared the problem. Hopefully the "new" jet will settle the idle.

Could the dripping also be from the inlet valve since the float hinge isn't held down properly? Without the leaf spring, the pivot may move and not close the valve properly I'm guessing

!

As I mentioned, I rebuilt the carb so the power valve diaphragm is new, that shouldn't be part of the problem now.

The threads for the idle jet in the carb look good. The brass on the barrel of the jet is very thin so that's why the metering holes have deformed before doing damage to the carb's aluminum body.

BQS4 has sent me a "new" jet and the hold down clip for the float hinge. I'll let everyone know how the repair goes when I get the parts.

The idle mixture needle screw is very difficult to get at in the GT and the water choke hoses just happen to be in the way (and warm) too

! And with the o-ring on the shaft it's difficult to turn. I'll have to invest in a flexible screwdriver this week!

Harold.

gr_diver · 09-10-2007

If it was due to the missing leaf spring, it would more probably drip in both barrels, as the float chamber would be flooding. So it must be the high idle, and thus, it MIGHT be normal, since you are getting into the main jet's effective range. Changing the damaged parts will be the definite answer to than...

Also, to fight the "difficult to turn" idle screws, get a silicone lubricant spray. Bottom in both screws (GENTLY), counting turns from what you have them set at, and then remove them. Spray the o-rings and the holes with the lubricant, re-insert the screws in, bottom them in, and count backwards the number of turns you previously counted, to get them where they were... This will keep them soft and easy to adjust...

And to make the idle adjustment correct, you must verify that the primary throttle valve is set so that you will get a specific amount of vacuum at the ported vacuum nipple. If you haven't set it this way, please do a search in the forum, as it has been covered in the past...

Keep us posted!

Crazy Harry · 09-10-2007

I saw some posts about the throttle stop screw. You adjust to 6" water I believe. But what conditions? Does idle speed matter, should the engine be warm, can the air filter cover be removed for that step, etc.? I have a factory service manual as well, I'll re-read the carb setup section, but I believe that step is after the basic idle set up?

Thanks,

Harold.

gr_diver · 09-11-2007

It indeed is set for 6" water vacuum...

The whole procedure is this:

You set the carb's screws to their initial settings. You start the engine, let it fast-idle until it is fully warmed up (20-25mins minimum, in order to get the oil up to temp).

Then you let it slow idle (verify that the throttle stop screw is in contact with it's "stop"), disconnect the vacuum hose that goes to the distributor, and connect a good vacuum gauge to the carb's nipple. Set the throttle valve screw to achieve 6" vacuum, and forget it until the next re-build. This screw is there only to control the transition from the idle circuit to the progression circuit (in fact, to control how much of the progression hole will be uncovered at idle), and it is not to aid in adjusting the engine's idle speed.

Then briefly adjust the idle speed using the air-speed and mixture screws around 800-850rpms, (below 950, so that the mechanical advance does not come into play). Now check your dwell/timing settings, and if they are correct, proceed to adjust the idle speed from the carb. The manual states to set for a best-running idle 50rpms more than the desired rpms, and then reduce it to the desired rpms with the mixture screw, to achieve proper emissions.

That's all about it!!! Sounds complicated but it is easy! And it is the only way to achieve a stable idle, and a good transition.

I hope these were of help!

Antonis

Crazy Harry · 09-11-2007

Antonis,

Thanks for all the tips. I think I've got it now, seems relatively easy like you said. I let you know how it goes!

Harold.

Crazy Harry · 09-20-2007

Thanks to Gene I now have a leaf spring holding the float hinge and a good idle jet. The parts were installed and the dripping is gone. I still haven't got the idle quite were its supposed to be, but there was an improvement from before. I guess I'll have to spend some more time on it!

Harold.

OriginalOpelGTOwner · 07-30-2008

I have a 1971 Opel GT manual with a solex carb. I want to check the basic idle adjustment. I understand the initial idle fuel mixture adjustment setting is 2 1/2 turns and the idle air adjustment initial setting is 2 turns. Is this correct?

The factory setting on the idle fuel mixture needle valve is 4 turns and I have the idle air needle valve at 3 times. My idle was alway 1000 rpm but it has become irratic and now goes anywhere from stall to 850 rpm at this setting. Any rpm above idle is smooth, no hesitation, no missing with no loss of power.

I have read all the posts and this is my current engine status:

Compression cold/dry: 130 psi all 4 cylinders
Dwell: 50 degrees
Timing: O degrees TDC
Vacuum: 18 in Hg at 850 rpm and steady.

Voltages, electrical and fuel components tested good. Brake booster works and no vacuum leaks. All other vacuum hoses new. Checked carbuetor float and needle valve both OK. No carbuetor warpage. All jets and passageways clean.

I have noticed the my gas sometimes boils and starts to drip into the carbuetor at the venturas. Comes and goes.

I am actually starting to suspect the quality of the last tank of gasoline. I am down to 1/4 of a tank so will know when I fill it up in the next couple of days.

Your thoughts are welcome. I know get a weber. I will if all else fails but I am sure I can get this solex to idle properly again. Has always been a stable carbuetor until now.

pecje · 07-30-2008

Originally Posted by OriginalOpelGTOwner

I have noticed the my gas sometimes boils and starts to drip into the carbuetor at the venturas. Comes and goes.

Had the same problem with my Solex carb.
It was caused by a leaking Float needle valve. A very small chip of metal (from my chromed fuel-line) had boken off and from time to time blocked the needle valve, causing it to leak.
I cleaned the Float needle valve and since then I haven't had problems anymore.
It's also recommended to place an inline fuel filter to prevent foreign material out of the petrol to block the Float needle valve and the jets.

Good luck in trying to find the cause of your problems.

Best regards Patrick

Crazy Harry · 07-30-2008

Originally Posted by OriginalOpelGTOwner

I have read all the posts and this is my current engine status:

Compression cold/dry: 130 psi all 4 cylinders
Dwell: 50 degrees
Timing: O degrees TDC
Vacuum: 18 in Hg at 850 rpm and steady.

Isn't the 18" Hg too high a vacuum? I thought the vacuum was to be set to 6 inches water according to the manual. Someone correct me if I'm wrong since I'm still having trouble keeping my engine running after a Solex rebuild and trying to set to 6" water.

Harold.

RallyBob · 07-31-2008

Originally Posted by Crazy Harry

Isn't the 18" Hg too high a vacuum? I thought the vacuum was to be set to 6 inches water according to the manual. Someone correct me if I'm wrong since I'm still having trouble keeping my engine running after a Solex rebuild and trying to set to 6" water.

Harold.

18-22 inches of vacuum is normal manifold vacuum for an Opel. I'm not sure what the 6" of water number is relevant to, nor from where it's measured as I have purposely avoided Solexes whenever possible for half my life!

tomking · 07-31-2008

Originally Posted by Crazy Harry

Isn't the 18" Hg too high a vacuum? I thought the vacuum was to be set to 6 inches water according to the manual. Someone correct me if I'm wrong since I'm still having trouble keeping my engine running after a Solex rebuild and trying to set to 6" water.

Harold.

The 6 inches of water column is the vacuum level at the dizzy port on a Solex at idle.

tekenaar · 07-31-2008

Originally Posted by tomking

Originally Posted by Crazy Harry

Isn't the 18" Hg too high a vacuum? I thought the vacuum was to be set to 6 inches water according to the manual. Someone correct me if I'm wrong since I'm still having trouble keeping my engine running after a Solex rebuild and trying to set to 6" water (H2O).

Harold.

The 6 inches of water column is the vacuum level at the dizzy port on a Solex at idle.

. . . apples and oranges too, I'm afraid . . . Hg (Mercury) and H2O (Water) . . .

Crazy Harry · 08-01-2008

Originally Posted by tekenaar

. . . apples and oranges too, I'm afraid . . . Hg (Mercury) and H2O (Water) . . .

Not really apples and oranges, but they are different fruit that measure pressure/vacuum:

1" Hg (mercury) = 13.59" water

I guess we should be more specific as to where this vacuum is being measured!

Harold.

gemacmanus · 09-12-2009

Originally Posted by tekenaar

Your problem may indeed be a vacuum leak of some sort, but I'd check the setting of the choke when the engine is cold FIRST!

While engine is cold, step on throttle ONE time to 'set' choke . . . DO NOT START engine! Remove snorkel on top of carburetor and check condition of choke blade in primary (outer barrel). If closed (correct), push on lower edge of choke blade with your finger, it should have some spring tension.

If choke blade is open, adjust choke per manual.

I recently had a conversation with a retired foreign car mechanic (old English and German cars) Have similar problems w my GT. He said it sounds like a vacuum problem, possibly with advance/retard diaphram on the distributor. Old rubber becomes cracked or torn. Can't adjust to different low rpms. Didn't say how to fix. Gary1

tekenaar · 09-13-2009

Originally Posted by gemacmanus

Originally Posted by tekenaar

Your problem may indeed be a vacuum leak of some sort, but I'd check the setting of the choke when the engine is cold FIRST!

While engine is cold, step on throttle ONE time to 'set' choke . . . DO NOT START engine! Remove snorkel on top of carburetor and check condition of choke blade in primary (outer barrel). If closed (correct), push on lower edge of choke blade with your finger, it should have some spring tension.

If choke blade is open, adjust choke per manual.

I recently had a conversation with a retired foreign car mechanic (old English and German cars) Have similar problems w my GT. He said it sounds like a vacuum problem, possibly with advance/retard diaphram on the distributor. Old rubber becomes cracked or torn. Can't adjust to different low rpms. Didn't say how to fix. Gary1

. . . disconnect vacuum line(s) from dizzy vacuum advance/retard canister and use hand vacuum pump to verify leakage at either side there. If either retard or advance diaphragm is leaking, nothing to do except replace the vacuum canister(s)!

opelgtroma1970 · 3 Weeks Ago

hello
my solex carb don't have"C - idle air (speed) adjustment"
I can use a normal bolt?
I can use a jet?
thanks.

opelgtroma1970 · 3 Weeks Ago

my solex

BQS4 · 3 Weeks Ago

Originally Posted by opelgtroma1970

hello
my solex carb don't have"C - idle air (speed) adjustment"
I can use a normal bolt?
I can use a jet?
thanks.

Can you post a picture of what is missing off your solex?

opelgtroma1970 · 3 Weeks Ago

my solex

09-09-2007	#26 (permalink)
Crazy Harry Opeler Join Date: Jan 2007 Location: Oakville, Ontario, Canada Posts: 94 Real Name: Harold Provided Answers: 1	Solex Idle Air Jet Tomking, I'm still going through all the post in the forum. I had to print them and am half through the stack of paper! I agree that the screwdriver slot is not the problem, that photo was more to show the jet's size marking. My concern with the idle air jet is the deformed holes on the barrel, I'm sure they're supposed to be round and not squashed like the photo. The little hole in the end looks OK and the area of the barrel holes is probably larger than the real orifice. I believe it still seats properly. I put some ink on the sealing surface, reinstalled and then removed the jet, all ink was gone. Prior to the rebuild I could get the engine to run quite smoothly by playing with the position of this jet, even though this is not a legitimate adjustment. BQS4, If you can 'part' with the leaf spring that holds the float hinge and the idle air jet, size g47.5 that would be great . Let me know what I owe you! I've sent a PM with my address. All suggestions and help are more than welcome! Thanks, Harold.

09-09-2007	#28 (permalink)
Crazy Harry Opeler Join Date: Jan 2007 Location: Oakville, Ontario, Canada Posts: 94 Real Name: Harold Provided Answers: 1	Those are the parts! Gene, That's exactly what I'm looking for! Hope I didn't keep you up too late tonight! I hope they solve my troubles. Thanks, Harold.

09-09-2007	#29 (permalink)
BQS4 Southern Red Neck Join Date: Mar 2002 Location: Snellville, GA Posts: 6,028 Real Name: Gene Provided Answers: 12	Nah, I keep an almost complete inventory in the back of my Sportwagon, ask anyone who has seen my Wagon at Carlisle! Just kidding, It may be a day or so before I can get by the Post Office, as we're up to our ears in work, but, hang on, help's on the way!! __________________ "Yes, I do have a rifle rack in my Sportwagon"

09-10-2007	#31 (permalink)
gr_diver Senior Contributor Join Date: Feb 2005 Location: Greece Posts: 540	With so much deformation on the idle jet I would be concerned about the condition of the threads where the jet gets screwed in. I think it would be easier to strip the threads than bend the jet that much. The carb's body is a soft alloy, so check that the threads are in good condition The damaged idle jet is a sure cause for headache! Those bent holes are the metering holes for the air, that gets in from a tiny hole at the air-horn. The fuel enters the jet from the tiny hole at the small end. So the idle/progression mixture is not properly aerated. But I don't think it is related to the interminent dripping of fuel from the primary main jet, unless... ...Unless the dripping that you describe happens with the engine idling high (as you describe you have to set it now). If the replacement jet solves the high idle (I bet it will), and then the dripping continues verify that the diaphragm in the power valve is in good condition. They tend to get hard and jam the piston in the open position... __________________ '78 Opel Ascona B 1.6SR ______________R.I.P.____________

09-10-2007	#33 (permalink)
gr_diver Senior Contributor Join Date: Feb 2005 Location: Greece Posts: 540	If it was due to the missing leaf spring, it would more probably drip in both barrels, as the float chamber would be flooding. So it must be the high idle, and thus, it MIGHT be normal, since you are getting into the main jet's effective range. Changing the damaged parts will be the definite answer to than... Also, to fight the "difficult to turn" idle screws, get a silicone lubricant spray. Bottom in both screws (GENTLY), counting turns from what you have them set at, and then remove them. Spray the o-rings and the holes with the lubricant, re-insert the screws in, bottom them in, and count backwards the number of turns you previously counted, to get them where they were... This will keep them soft and easy to adjust... And to make the idle adjustment correct, you must verify that the primary throttle valve is set so that you will get a specific amount of vacuum at the ported vacuum nipple. If you haven't set it this way, please do a search in the forum, as it has been covered in the past... Keep us posted! __________________ '78 Opel Ascona B 1.6SR ______________R.I.P.____________

09-09-2007	#30 (permalink)
Crazy Harry Opeler Join Date: Jan 2007 Location: Oakville, Ontario, Canada Posts: 94 Real Name: Harold Provided Answers: 1	That's great Gene, I can wait knowing help is on its way! Thanks again, Harold.

09-10-2007	#32 (permalink)
Crazy Harry Opeler Join Date: Jan 2007 Location: Oakville, Ontario, Canada Posts: 94 Real Name: Harold Provided Answers: 1	gr_driver: The dripping is at high idle and seems to be at constant driving speed as well. It was at low idle before the rebuild as well. I did notice that backing out the idle jet (I guess it let some more air in around the threads) cleared the problem. Hopefully the "new" jet will settle the idle. Could the dripping also be from the inlet valve since the float hinge isn't held down properly? Without the leaf spring, the pivot may move and not close the valve properly I'm guessing ! As I mentioned, I rebuilt the carb so the power valve diaphragm is new, that shouldn't be part of the problem now. The threads for the idle jet in the carb look good. The brass on the barrel of the jet is very thin so that's why the metering holes have deformed before doing damage to the carb's aluminum body. BQS4 has sent me a "new" jet and the hold down clip for the float hinge. I'll let everyone know how the repair goes when I get the parts. The idle mixture needle screw is very difficult to get at in the GT and the water choke hoses just happen to be in the way (and warm) too ! And with the o-ring on the shaft it's difficult to turn. I'll have to invest in a flexible screwdriver this week! Harold.

09-10-2007	#34 (permalink)
Crazy Harry Opeler Join Date: Jan 2007 Location: Oakville, Ontario, Canada Posts: 94 Real Name: Harold Provided Answers: 1	I saw some posts about the throttle stop screw. You adjust to 6" water I believe. But what conditions? Does idle speed matter, should the engine be warm, can the air filter cover be removed for that step, etc.? I have a factory service manual as well, I'll re-read the carb setup section, but I believe that step is after the basic idle set up? Thanks, Harold. Last edited by Crazy Harry; 09-10-2007 at 07:20 PM.

09-11-2007	#35 (permalink)
gr_diver Senior Contributor Join Date: Feb 2005 Location: Greece Posts: 540	It indeed is set for 6" water vacuum... The whole procedure is this: You set the carb's screws to their initial settings. You start the engine, let it fast-idle until it is fully warmed up (20-25mins minimum, in order to get the oil up to temp). Then you let it slow idle (verify that the throttle stop screw is in contact with it's "stop"), disconnect the vacuum hose that goes to the distributor, and connect a good vacuum gauge to the carb's nipple. Set the throttle valve screw to achieve 6" vacuum, and forget it until the next re-build. This screw is there only to control the transition from the idle circuit to the progression circuit (in fact, to control how much of the progression hole will be uncovered at idle), and it is not to aid in adjusting the engine's idle speed. Then briefly adjust the idle speed using the air-speed and mixture screws around 800-850rpms, (below 950, so that the mechanical advance does not come into play). Now check your dwell/timing settings, and if they are correct, proceed to adjust the idle speed from the carb. The manual states to set for a best-running idle 50rpms more than the desired rpms, and then reduce it to the desired rpms with the mixture screw, to achieve proper emissions. That's all about it!!! Sounds complicated but it is easy! And it is the only way to achieve a stable idle, and a good transition. I hope these were of help! Antonis __________________ '78 Opel Ascona B 1.6SR ______________R.I.P.____________

09-11-2007	#36 (permalink)
Crazy Harry Opeler Join Date: Jan 2007 Location: Oakville, Ontario, Canada Posts: 94 Real Name: Harold Provided Answers: 1	Antonis, Thanks for all the tips. I think I've got it now, seems relatively easy like you said. I let you know how it goes! Harold.

09-20-2007	#37 (permalink)
Crazy Harry Opeler Join Date: Jan 2007 Location: Oakville, Ontario, Canada Posts: 94 Real Name: Harold Provided Answers: 1	Still Tweaking! Thanks to Gene I now have a leaf spring holding the float hinge and a good idle jet. The parts were installed and the dripping is gone. I still haven't got the idle quite were its supposed to be, but there was an improvement from before. I guess I'll have to spend some more time on it! Harold.

07-30-2008	#38 (permalink)
OriginalOpelGTOwner Opeler Join Date: Apr 2006 Location: Michigan Posts: 137 Provided Answers: 2	I have a 1971 Opel GT manual with a solex carb. I want to check the basic idle adjustment. I understand the initial idle fuel mixture adjustment setting is 2 1/2 turns and the idle air adjustment initial setting is 2 turns. Is this correct? The factory setting on the idle fuel mixture needle valve is 4 turns and I have the idle air needle valve at 3 times. My idle was alway 1000 rpm but it has become irratic and now goes anywhere from stall to 850 rpm at this setting. Any rpm above idle is smooth, no hesitation, no missing with no loss of power. I have read all the posts and this is my current engine status: Compression cold/dry: 130 psi all 4 cylinders Dwell: 50 degrees Timing: O degrees TDC Vacuum: 18 in Hg at 850 rpm and steady. Voltages, electrical and fuel components tested good. Brake booster works and no vacuum leaks. All other vacuum hoses new. Checked carbuetor float and needle valve both OK. No carbuetor warpage. All jets and passageways clean. I have noticed the my gas sometimes boils and starts to drip into the carbuetor at the venturas. Comes and goes. I am actually starting to suspect the quality of the last tank of gasoline. I am down to 1/4 of a tank so will know when I fill it up in the next couple of days. Your thoughts are welcome. I know get a weber. I will if all else fails but I am sure I can get this solex to idle properly again. Has always been a stable carbuetor until now.

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