Solex rebuild

[jrohr]

I am preparing to pull and rebuild the solex off of my 71 GT and want to make sure I have all the parts to rebuild and put back on. I know, throw it out and install a Weber, which is the future plan, but for now, the Solex will have to do. Besides the rebuild kit, is there anything else I would need to purchase for this project? What about a mounting gasket? Does it come with the kit from OGTS? Anything else that should be considered? Thanks in advance for the information.

[yellaopelgt]

One thing that I found very useful to have when rebuilding carbs is found at most parts stores. A gallon of carb cleaner that has its own basket inside the can. Just set the parts in and dip. But be careful not to lose any small parts in the solution, as its NASTY stuff and the smell is awful!!! Took a few days to get the smell off my hands but really did an excellent job of cleaning. Cant remember the name brand off the top of my head but just ask for it and they will know what you need.Its been so long since I messed with a solex but check into the thicker spacer at OGTS. And put the heat shield on if you still have it.
HTH
Joe

[gr_diver]

The rebuild kit I used for the solex also included a gasket to use right below the carburetor. But since you will take it off, you might as well replace all the gaskets of the "manifold-gasket-heatshield-gasket-spacer-gasket-carburetor" assembly... It will be frustrating to reinstall the carb and have one of these gaskets fail...

And remember, do not tighten the carb-to-manifold nuts very much, or it might warp and get damaged. I usually go 3/4 of a turn beyond finger tight... And that has always been enough...

[tekenaar]

Originally Posted by gr_diver The rebuild kit I used for the solex also included a gasket to use right below the carburetor. But since you will take it off, you might as well replace all the gaskets of the "manifold-gasket-heatshield-gasket-spacer-gasket-carburetor" assembly... It will be frustrating to reinstall the carb and have one of these gaskets fail... And remember, do not tighten! the carb-to-manifold nuts TOO much, or it might warp and get damaged. I usually go 3/4 of a turn beyond finger tight... And that has always been enough...

Overtightening is the biggest Solex problem!

[RallyBob]

Originally Posted by tekenaar Overtightening is the biggest Solex problem!

However, I've seen more warped baseplates on Solex's and Webers from leaving one fastener too loose...namely the forward bolt near the valve cover. If the rest are tightened normally and one bolt is loose, the base warps. The issue of course is access to tightening that bolt, so a 90* offset-bent wrench is really a necessity here to do the job right. Weber wrench tip.

[briarrose]

I'm just the book keeper and info gatherer here, but the solex kit was 21 dollars with shipping from Opel GT source. The can of carburetor cleaner was 24.75 from autozone plus the 12.51 for short wrenches on sale at the freight company. We were quoted 250 by a local auto repair shop to get it to idle right. Was that a fair price? We went for the repair it ourselves plan and hope it turns out ok instead of spending the 250.

[Sparky73]

Could anyone post a picture of the gasket that fits directly underneath of the Solex Carb. Someone else posted their kit came with that gasket.. but the one I ordered from OGTS does not appear to have one with it.

Did I forget to order something? I ordered the kit, along with the thin and thick gaskets that are placed above and below the heat shield.

[Sparky73]

Is this the gasket that goes directly beneath the carb?

Also.. how many gaskets should there be? Carb, then Heat Shield, then Intake.. or am I missing something?

LOL Sorry.. my whole Carb and Intake setup was all custom so I have no idea how it should be stock.

[opel kid]

the "thick gasket" on mine is sitting from the carb to the heat shield,i think another thin gasket goes under the heat shield to intake so 2 gaskets total?
but i have a weber not a solex should be the same set up.

[Crazy Harry]

Sparky,

From the top down: Carb, thick gasket, heat shield, thin gasket, manifold.

Harold.

[Gary Sullivan]

I bought a 69 GT new with the Solex. We made several changes to it and neither I nor the dealer could get it to run well. I changed over to Webers and haven't had issues. What do you have to do to the Solex's so they don't run poorly? After I would come off the highway, the car would be "out of breath" for 5 minutes or so. Around town driving after highway driving was routinely lousy. Plus, in its first version we also still had that primitive EGR system as well. That also came out.
Are some of you running the Solex's and liking them?
Gary

[Sparky73]

Originally Posted by Gary Sullivan I bought a 69 GT new with the Solex. We made several changes to it and neither I nor the dealer could get it to run well. I changed over to Webers and haven't had issues. What do you have to do to the Solex's so they don't run poorly? After I would come off the highway, the car would be "out of breath" for 5 minutes or so. Around town driving after highway driving was routinely lousy. Plus, in its first version we also still had that primitive EGR system as well. That also came out. Are some of you running the Solex's and liking them? Gary

I have not heard of one person "recommending" a Solex, especially over a Weber 32/36. On my mom's old GT, my dad swore they never had a single problem with the original Solex, but I find that hard to believe after reading everything else others say. They are just extremely hard to fine tune properly, and come OUT of tune quite often..

[roundl]

I bit the bullet a few months ago and bought a new Weber. I had (still have) a rebuilt Weber but rather than wrestle with it I decided on a new one. It was the best think i did for my '71 Kadett. The install was easy and I'm amazed at how strong the motor sounds. I picked up a Pertronix electronic ignition and Flamethrower coil yesterday and plan to install them over Thanksgiving.

Anyone have any experience tossing a little Kadett around on the snowy winter roads of New England? I see a lot of Croatian dudes having fun with them over there on Youtube. It's light, but with the right snow tires and weight over the rear axle it should be a blast!

[tekenaar]

Originally Posted by Gary Sullivan I bought a 69 GT new with the Solex. We made several changes to it and neither I nor the dealer could get it to run well. I changed over to Webers and haven't had issues. What do you have to do to the Solex's so they don't run poorly? After I would come off the highway, the car would be "out of breath" for 5 minutes or so. Around town driving after highway driving was routinely lousy. Plus, in its first version we also still had that primitive EGR system as well. That also came out. Are some of you running the Solexes and liking them? Gary Originally Posted by Sparky73 I have not heard of one person "recommending" a Solex, especially over a Weber 32/36. On my mom's old GT, my dad swore they never had a single problem with the original Solex, but I find that hard to believe after reading everything else others say. They are just extremely hard to fine tune properly, and come OUT of tune quite often..

'69 GT, mechanical secondary Solex and air pump (AIR, NOT EGR - exhaust gas recirculation!), correct?

. . . about your car being "out of breath", that was most likely a fuel delivery problem of some sort - tank fuel sock, kinked fuel line, fuel pump, fuel filter, sticking fuel bowl needle/seat valve, float maladjusted . . . or maladjusted ignition timing. Not to belabor the point too much, but "no fix" is just a "poor mechanic's" result, IMO!

That said, if you changed "only" the carb and it had "no issues", then it pretty much eliminated everything except the underlined possibilities and "blame the carb, not the mechanic" mentality! And, since I don't believe that this was a "warped carb base" problem, there remains only one thing at which to point one's finger . . . if so inclined.

To answer your question and Sparky73's "majority" answer to it, I can only say that I've NEVER replaced a Solex on any of my Opels (since '76) because it didn't function as designed . . . correctly!

And again, I bought my '69 Kadett LS 1.9 A/T in Seattle about 4.5 years ago and drove the car back to Texas solo, points and all! The PO had had the Solex replaced with a Weber 32/36 e-choke, un-connected and "adjusted" open all the time, because her "mechanic" couldn't fix the Solex. Lucky for me, she had kept the original carb and air cleaner.

At the end of my trip back from Seattle, I found that the Solex still had its metal P/N tag attached to the float bowl . . . i.e. never even opened up to investigate its "problem!" I restored the car back to original . . . replaced the Weber with the original Solex.

What was wrong with the Solex? A/T Opels came with a vacuum-secondary Solex and after some preliminary checks for vacuum and gas leaks, I found it hard to adjust the idle speed with consistent results. Never had this problem before with Solex carbs, but that was with GT Solexes . . . mechanical secondaries!

Disassembled the secondary vacuum assembly and discovered a tear in the diaphragm . . . by far the most common problem in "vacuum" Solexes, BTW! Replaced it from a discarded donor Solex . . . for free, adjusted to factory specs and have not touched it since . . . ~4 years and running now!

To Sparky73 I would only add, don't be so quick to accept your peers' advice as "Gospel!" . . . and listen to your Dad!

[hallgeir]

I have to agree with Otto. Back in -79 I had an Ascona 1.6 S with a Solex with vacuum secondary, and after a rebuild (yes, it had a tear in the diaphragm) and adjusting, it worked very well for as long as I had the car.
I now have a GT with a Solex I got from Otto, and it runs perfect. Absolutely no problems at all.

[2 Fast 4 U]

I've only had Solex carbs on all of my Opels never had any problems!!!

[Anonymous D]

(There should be a disclaimer here: Information expressed on this board, particularly on technical issues, represents the OPINION of the poster,
and not necessarily objective fact).

FACT:
Solexes were so notoriously poor-running, that the state of California back in 1986 declared them a "gross polluter."

FACT:
Even GM/Opel knew this. Consider the voluminous size, of the "Technical Service Bulletins" that were devoted in the early 1970's to Solex tuning and repairs. (Hint: It wasn't just the diaphragm, that these addressed).

EXPERIENCE:
The Weber 32/36, in most cases, is a bolt-on repair. On the other hand, once a Solex starts to run poorly, either it needs a major rebuild (often including, machining the base plate flat) or at the least, replacement (not just "adjustment") of the internal float (which gets saturated and then "sinks" in the float bowl). You have to search for this float, as they are not manufactured new anymore (and are not in available rebuild kits).

It's true, that some individuals have had good experiences with the Solex. However, once a Solex goes "bad", it becomes an impractical hassle (and an ongoing expense) to try to make one run to factory specs again. (Heat warpage, common in warm climates, affects the internal air-correction circuits. This may not be a problem in Northern Europe, but it is in the SouthWest).

If you consider that your time and effort is worth money, then bite the bullet and solve that problem with a Weber.

[oldopelguy]

While we're at it, then:

Fact: A properly tuned Opel with a 1.9 and a Solex will achieve higher fuel economy than a properly tuned Opel with a Weber.

Fact: A Solex will work properly with the Opel mechanical fuel pump and most aftermarket electric fuel pumps, where a Weber almost always needs a fuel pressure regulator to function properly.

Fact: A Solex will install and properly retain all year-specific emissions controls, making it always legal in every state. Weber carbs come in emissions and non-emissions models and even the emissions ones do not always hook up properly and are not universally legal. It is up to the buyer to determine if the model carb purchased is correct.

There are lots of opinions out there on the Solex. Truth is that if the carb has managed to make it to now, 35 years later, un-molested and un-damaged, than it can probably be rebuilt and will most likely work excellently. Unfortunately, most of them have not made it thus far un-molested and un-damaged, and unless you have a lot of experience with them and some special tools you may not be able to tell if it's salvagable by just looking it over.

So, for the bulk of owners out there, especially the new-to-Opels owners, any $ spent working on the original Solex is probably wasted $ and they would be better off buying a Weber. Not just any Weber, though, make sure you get one appropriate for the rules where you live, and recognize that the expense for the install is likely to also include another $50-75 worth of additional support parts, including air filter and fuel pressure regulator. You will not be saving any $ by buying a weber, but you will most likely be wasting less $ than repairing a Solex in the long run.

[hallgeir]

Originally Posted by Anonymous D (There should be a disclaimer here: Information expressed on this board, particularly on technical issues, represents the OPINION of the poster, and not necessarily objective fact).

Well, this is NOT my opinion. This is FACT:

Originally Posted by hallgeir I have to agree with Otto. Back in -79 I had an Ascona 1.6 S with a Solex with vacuum secondary, and after a rebuild (yes, it had a tear in the diaphragm) and adjusting, it worked very well for as long as I had the car. I now have a GT with a Solex I got from Otto, and it runs perfect. Absolutely no problems at all.

Yes, my first Solex was poor-running until I rebuilt it (the whole thing, not only the diaphragm).
The second one (from Otto), has just been adjusted, and it runs great.

[GTJIM]

Solei are excellent carbs ... as long as they have not been "messed" with and are used on essentially stock motors. Otherwise, Opel, BMW, VW, Audi, Mercedes, et al would not have used them for so long on their quality cars!

The problems occur when: 1) someone 'fixes' them - inexpertly.... 2) the motor is changed from standard configuration - necessitating changes in the fuel metering. 3) They get old and warped/worn

Webers are designed to be far more easily 'tunable' - and can still be bought NEW

[Anonymous D]

If "Solei" are "excellent," then why did GM/Opel find it necessary to issue Technical Service Bulletins:

68-T-06,
69-T-01,
69-T-07,
70-I-13,
70-I-19,
70-I-33,
70-T-04,
70-T-06,
71-I-22,
71-T-04,
71-T-13,
72-T-01,
72-T-01a,
72-T-01b,
72-T-03,
72-T-04,
72-T-05,
74-T-02,
74-T-03,
and 74-T-04,

Which address diagnosis and repair of faulty Opel fuel system operation?

[GTJIM]

Originally Posted by Anonymous D If "Solei" are "excellent," then why did GM/Opel find it necessary to issue Technical Service Bulletins:?

American 'mechanics' kept messing with them - Someone had to try and let them know how to fix them!

[tekenaar]

Originally Posted by Anonymous D (There should be a disclaimer here: Information expressed on this board, particularly on technical issues, represents the OPINION of the poster, and not necessarily objective fact). FACT: Solexes were so notoriously poor-running, that the state of California back in 1986 declared them a "gross polluter." FACT: Even GM/Opel knew this. Consider the voluminous size, of the "Technical Service Bulletins" that were devoted in the early 1970's to Solex tuning and repairs. (Hint: It wasn't just the diaphragm, that these addressed). EXPERIENCE: The Weber 32/36, in most cases, is a bolt-on repair. On the other hand, once a Solex starts to run poorly, either it needs a major rebuild (often including, machining the base plate flat) or at the least, replacement (not just "adjustment") of the internal float (which gets saturated and then "sinks" in the float bowl). You have to search for this float, as they are not manufactured new anymore (and are not in available rebuild kits). It's true, that some individuals have had good experiences with the Solex. However, once a Solex goes "bad", it becomes an impractical hassle (and an ongoing expense) to try to make one run to factory specs again. (Heat warpage, common in warm climates, affects the internal air-correction circuits. This may not be a problem in Northern Europe, but it is in the SouthWest). If you consider that your time and effort is worth money, then bite the bullet and solve that problem with a Weber.

It's a little difficult to determine from your post's tone if that little "admonition" at the beginning is meant for just the rest of us or includes you too?! I do believe that this is already the generally understood and accepted practice here, IMO . . . most certainly by me . . .

[West Coast GT]

Solex? Weber? How the hell would I know which is better? But here's what I've noticed;

1. The Solex is one hell of a lot easier to remove and reinstall than the Weber.
2. The Weber's primary and secondary bores are significantly larger than the Solex.

I'll stick to the Solex until I decide the extra "oomph" is worth the hassle of swapping out the carb, and worth the additional cost.

[Sparky73]

So I was wrong about the Solex. I guess opinions go both ways! The majority of people would recommend a Weber over a Solex.. better?

Back to the original topic here though.. tomorrow I am putting everything back together, and have never really seen (in person) how the original Manifold/Heat Shield/Solex go together. I (now) know the thick gasket goes between the Carb and the Heat Shield, and the thin between the Heat Shield and the the Manifold.. BUT how is the heat shield placed? I can't for the life of me, figure out how its placed on the manifold. I seem to have it upside down, or reversed.. or something!

Also.. are there studs for the intake manifold like there are for the exhaust to head pipe? On the top of the intake, where it bolts to the Carb.. there are threaded holes.. yet the holes in the carb are not threaded. Picture below:

Also.. I added some arrows with numbers.. pointing to 3 threaded holes, and a valve. What are these for, and is the valve supposed to be pointing straight up or which way?