Solex carb question

[72skylark]

72 manta, 1.9 liter. stock carb

At idle it drips fuel from the main jet pretty good, give it a little gas and it drips alot more. it seems to like to idle at 1200 RPM's, and has okay power, but doesn't really get going till 4k. It also backfired once when I shut it off. (it isn't driven about 1 or 2 times a week)

I checked the power valve (or whatever it's called on a solex carb). Everything checked out ok.
So I'm thinking maybe the float is two high. The car has been sitting for a while since I got it a few months ago. Or posibally the needle valve isn't closing 100%..
Anyone know any other possible problems?

Can the float setting be made externally, or do I have to take it apart to adjust it?
Also if I have to take it apart, which I might anyway for a rebuild, where can I get a rebuild kit for this carb?

Thanks much,
-Nick

[1972ACGT]

I think the best fix for your Solex is to replace it with a Weber.

[mjustice]

I agree....The only thing they're good for is an interesting paperweight! (and not even that interesting at that!)

Do youself a favor and junk the solex....you'll be VERY happy you did!

[Gary]

Nick, One old mechanics trick was to remove the air cleaner, rev the engine up to ~3,000rpm and put your hand over the carb to block the air flow for a second then pull your hand away. This creates a high vacuum in the upper carb body and can clean out blocked jets that can cause problems.

If that doesn't work, remove the top of the carb and look for crap in bottom of the fuel bowl. Then check the condition of the float and the needle and seat. There could be something on the needle valve that stops it from closing off the fuel flow.

For ultimate reliability, the 32/36 Weber is the way to go.

[72skylark]

I'd love to replace it with a weber see, I really would, but I've got 2 other cars that are getting a little more financial attention. Right now the opel is just a tinker-toy, ya know? Just get it running good, slowly fix it up, and when the other toys are finsihed give it some more attention.
If I can get a rebuild kit for the solex, I'd be happy. I'd hate to pull off the top without a rebuild kit, and rip the gasket... then I'd be in a bind...

[TGSI Racing]

You can get Solex kits and... not takeing the carb off without rebuilding it is a bad idea... but taking the solex off and not "pitching it" would be an even worse idea. You may go to a lot of pain and aggrivation and a rebuild kit and the thing still wouldn't work well.

Do some searching (ebay ? or maybe someone on this site can help you out) for a used 32/36 Weber and then buy a rebuild kit for it.

The best use I have ever found was at an Opel Club picknic a few years ago... the "Solex Putt" event.

[19693SGTEOPEL]

SOLEX = JUNK trash it. get side drafts pain to tune though. Stick with WEBER you can not go wrong!!!!!

[72skylark]

$150+ for weber swap vs $14.95 for solex rebuild kit..... hmmm decisions, decisions, decisions....
I had them look up a carb rebuild kit at autozone a while ago... nothing was listed... in fact they pulled up the complete list of things they have for my opel, and it had like 3 things in it. But now they have alot of things listed. Even have a master cylinder list for $40.....
anyway they have the carb kit, so I'm gonna invest $15 and 2 hours and rebuild the solex.

everyone says the solexes are junk, but why are they junk? Any actual reason besides everyone complains about them? is there any actual design flaw with them?

[RallyBob]

Yes, they are flawed. Once they leak, they will leak again, even with a rebuild kit. It may take a while (or not), but the problem will resurface. The castings tend to warp, that is one of the major flaws. In general, it's not even worth the time to work on one, even for the perceived cost savings.

Bob

[kwilford]

Bob, I, and about 4/5 of the Opel Community are in agreement on this one. While there are a few die-hards (notably Katheryn McCoy, who has "Crazy" in her nickname), virtually EVERYONE who has done the swap says it is the best (place price here: $50, $100, even $300!) they spent on their Opel.

My GT had a Solex when I first bought it in 1978. I bought and installed a rebuild kit, and then did everything but do Voodoo (apologies to Thom) to try to make it work. I was finally told by a dealer mechanic that there are internal check-balls that fail, and are NOT repairable. He was probably giving his time-tried excuse why he couldn't get them to work either, and convinced many an Opel owner to fork out BIG bucks for a new Solex. I have never had that specific fact checked, but within the first moment of installing a Weber, it ran 500% better.

That was a 32/36 DFM, which is NOT the optimum Weber model, but it is about to be replaced by a 32/36 DGAV. I bought it on ebay for $51, and the rebuild kit cost about $100. They often show up and sell for between $50 and $125, depending on condition. John Warga just bought one in a "buy it now" bid for $75, and it was like new. So just be a little persistent. Or visit one of the Weber aftermarket places, such as OpelGT Source, or http://www.piercemanifolds.com/ or http://www.racetep.com/weber.html to pay the big bucks and get a new one.

Now, by all means, pay the $15 (if is that cheap) and get the rebuild kit. And install it, and carefully set up your Solex according to the factory manual, paying special attention to the butterfly setting (USE A MANOMETER TO SET THE THROTTLE PLATE!) and then adjust the mixture and idle air-speed screw. If it works, great, you are only out $15 and a couple of hours. But if it doesn't work (and the audience says it won't), get a Weber.

JM2CW

[tekenaar]

Want less maintenance problems and more performance, though mileage will suffer, from your carb? Get a Weber . . . ANY Weber, at least that is the consensus in this forum. ANYTHING that decreases periodic maintenance on a car is a BIG PLUS to me, so in general, I would agree with what's being said here. But to tell the WHOLE story, let's discuss for a moment why this is so.

With few exceptions, most German car manufacturers, including Audi, BMW, Mercedes and VW, used Solex carbs before everyone began using Bosch FI systems. Each Solex carb type was designed and tuned for a specific engine's operational requirements, displacement, operating range, emissions and economy among design considerations. That's what you get with a "stock" carburetor . . . compromise!

By contrast, Weber carbs are by and large "stock" only on some, primarily Italian, "exotic" cars, which are by definition "low volume". So Weber's basic design specification had to place a much higher premium on adaptability to a range of engine operational requirements, ie same basic carb used on many different engines, or they wouldn't be price competitive in the aftermarket.

But that's only part of it. In the days our "bread and butter" engines were designed, GM, and therefore Opel, loved exhaust heated carburetor plenums in their "non-crossflow" head, in-line engines and even all their domestic V-8s. That's great for "cold-start" fuel atomization but is detrimental to performance once engine is up to operating temperature because you can't shut it off.

This wasn't a problem in domestic usage as most of the carburetors used had cast iron throttle plates, not prone to warpage no matter how "ham-fisted" back-yard mechanics were bolting these back onto manifolds. Opels used not only aluminum manifolds, but also carburetors with aluminum trottle plate bases, our Solex.

I don't have to tell anyone here that aluminum is much less forgiving of fastener torque variations than cast iron. Couple that with a heated plenum directly below the carb and it's easy to see a potential cause of warpage, much more likely here than on our "Detroit Iron" of yesteryear.

One of the biggest problems I've found with Solexes is that the tiny "air corrector" jets (round brass circular plates with tiny hole in center) in the carb throats tend to plug up with the least amount of dirt buildup. When they do, the mixture is no longer emulsified (aerated), carb will run rich, engine becomes sluggish and mileage suffers. Webers' are not located directly in the throats, so do not suffer from this problem.

OK, said my piece and I feel better. BTW, I currently own two "stock" Opels with Solexes and don't intend on changing either. Matter of fact, I converted my '69 Kadett back from PO's Weber to the original Solex and air cleaner, wasn't just tossed, thank God.