Just Can't Get It

[Opeler2]

O.K i've spent the whole 3 day weekend trying to get the 73 opel GT running. Recently rebuilt engine, New distributor, Rebuilt solex carb, header, all new fuel lines, every thing in the engine compartment is either replaced or new/rebuilt including the gas tank. Heres the problem timing is set and correct car lacks power stumbles at idle when i do get it idleing good, no power when the idle is rough car has more power but still sluggish. The carb and the engine was rebuilt by the previous owner and intially the timing was 180 out. Any experienced New England Opelers want to come take a look you guys could probably diagnose it in an hour.

[nobody]

I think I'd start with a dwell angle check and then a vacuum check.

[opelwasp]

it may also be the boat anchor of a solex. notorious for running like crap, even after a rebuild.

[69grngt]

You said that the timing was off by 180 degrees - I assume that the distributor was improperly installed - after correcting did you remember to moRogerve the spark plug wiring to the corrected firing order?

[Opeler2]

Thanks for the responses.
I forgot in the original post that I installed a pertronix ignitor instead of points.
Yes spark plug wires are all correct I will check vacuum asap but I,ve redone and rechecked all vacuum lines and connections probably 5 times now.

[RallyBob]

Do you have a vacuum gauge to actually check the vacuum level? A stock engine should pull 20-22 inches at idle speed (800-900 rpms).

Solex's are notoriously bad for internal leaks. Bill Daley is one of the very few who can get a Solex to run perfectly (I've driven all his cars with Solex's), and they start like EFI, idle smoothly, and accelerate with no hesitations.

BUT, even Bill states that for approximately every 10 Solex 'cores' he gets, only 1-2 are useable because the baseplate warps. Once it warps internally, nothing lines up, and vacuum leaks abound (even if the bottom is milled flat).

I had one Manta with a perfect Solex, and I left it 'as is' since it had excellent response. But I promised myself that the day it stumbled I would toss it away and put a Weber on it. It ran perfectly for 6 days, and after that the car stalled going through an intersection and I almost got hit by another car. That was it! Never had another problem once I went Weber.

So I'm not saying Solex's can't work okay, I'm just saying that properly running Solex's are a rare breed.

Bob

[netandtim]

Aloha,
If you replaced the fuel lines you may want to check for a pinch. I did that on a motorcycle once and it can be done under the hood of an Opel too. also see if the fuel pump is giving good pressure. I'm not sure what psi should be but i would guess about 7 to 10. the hillbilly way of checking is to take the line lose at the carb and put it into a bucket and have your friend turn on the ignition, you should get a nice squirt that is followed by more than a trickle. also pull the plugs to read them. black is to much fuel brown is nice and, someone help me here , white is to lean (i think its white?) but coco or dark brown is best. also take # 1 plug wire lose and hold it near the block/head WITH INSULATED PLIERS (otherwise, OUCH! ) and have a friend try to start it. you should see a nice white spark, if not you could have a weak coil. and the guys were right about the carb. there is a reason webber is so popular. wish you luck
tim

[BDD]

Just a note:
I didn't like my Solex that I had on my 1970 GT but I do notice that the Arnoldt Bristol speedster, an excellent and no doubt fast car for it's day used Solex carburetors and a BMW engine.

[RallyBob]

Originally Posted by netandtim I'm not sure what psi should be but i would guess about 7 to 10.

That would be a wee bit too high (but perfect for a Holley). You want to see 2.5 to 3.5 psi for a Solex or Weber. A Weber in particular will not run well with over 4.5 psi, it will flood.

[guyopel]

When I was servicing Opels at the dealer where I worked I had a 55 gal. drum full of solex carbs to rob parts from to try & keep a solex running.
I always tried to get owners to change to the weber carbs. HTH

[saxybiker]

We recently had a similar problem with Opie. Shortly after we brought him from Florida, we swapped in a high compression engine from a 69 parts car we had. We replaced the distributor with a brand new one (right out of the box). I could get it to idle fine, but it had absolutely no power. After talking to some of our Opel buddies, most thought it was a timing problem.

We found out that the distributor was for a 75 fuel enjected engine, so the curve was wrong if I were to try to use the usual timing method. Old Opel Guy suggested we try starting it off 32 degrees advanced and see what happens. BOY WHAT A DIFFERENCE! The car has some other issues that I'm working through, but lack of power isn't one of them!

Something to consider as you're trouble shooting. Find out what year your new distributor is supposed to be curved for. Maybe you can even try the famous "Otto method" for tuning if you don't have a timing light with an advance on it.

Best of luck!

Allen Gage

[RallyBob]

Originally Posted by richrosenberger Any experienced New England Opelers want to come take a look you guys could probably diagnose it in an hour.

Is the car driveable yet? Or on the other hand, what town are you located in?

Bob

[Opeler2]

rallybob

The car is not driveable yet it would take quite some time to get to Conneticut. The car is located in Mendon Massachusetts about an hour from Hartford my avatar is actually a picture of the car I bought it from a guy in Danbury.

[Opeler2]

The Dist. came from Rock auto as a rebuild.

[Opeler2]

The only thing I have not isolated to determine if its a vacuum problem is the brake booster. I don't know why I overlooked it but I have a feeling thats where the problem is.

[Gary]

Originally Posted by richrosenberger The only thing I have not isolated to determine if its a vacuum problem is the brake booster. I don't know why I overlooked it but I have a feeling thats where the problem is.

Easy enough to check... plug the hose connection or use a vise grip to *gently* clamp the hose.

[Opeler2]

well it was not the brake booster and the vacuum reading was good at idle 20 and steady. Anybody want to buy a half dozen solex carbs!!!!!!!!!!

[Opeler2]

well as it turns out the secondary butterfly was not opening at all so I robbed a diaphram off one of the other carbs in my bucket of spares and behold a normal running engine also explains the vacuum situation. I also got rid of the header as it leaked at every exhaust port and nothing could be done to fix it. I guess with this type of intake/exhaust manifold setup the header flange has to perfect in order for it to seal properly. I'll have to see what can be done to fix it.