Opel GT Forum banner

1 - 20 of 46 Posts

·
Registered
Joined
·
197 Posts
Discussion Starter · #1 · (Edited)
New Weber Installed..Questions

OK, UPS shows my new Weber to be delivered today! Can't wait to get home. Anything special I should think of, or need to buy? Is it as easy as unbolting the old carb, and bolting in the new?..then the normal adjustments of course.

Also, do I have to hookup the electric choke now, or can it wait? I remembered a post which says to hook it up to the wire going to the horn.
 

·
Member
Joined
·
328 Posts
weber carb

You will need the ball nut from the slowex carb, will you be opening up the intake?? Also a good idea to reuse the heat shield, it is there for a reason.
 

·
Member
Joined
·
1,219 Posts
Make sure you use new gaskets to avoid vacuum leaks, don't overtighten the base bolts, and recheck for tightness in a week or two.
 

·
Registered
Joined
·
197 Posts
Discussion Starter · #4 ·
I wasn't planning on opening the intake. I would hope that the conversion kit comes with new gaskets.....I guess I'll find out.
 

·
Opel Tinkerer and Rescuer
Joined
·
7,517 Posts
One MAJORLY unmentioned thing...

Remove the studs from the intake and get shorter studs. Memory fails me as to how short. But about 1/2"-3/4" shorter than the old ones. Trust me you will save a lot of time and get a better seal to the intake.

Charles
 

·
OPEL-LESS!!!
Joined
·
2,116 Posts
charles is right, the studs are too long, they dont have enough thread to hold the carb down tight enough, so get shorter studs as he suggested, or if your cheap like me, just find some old bolts with the right threads and bolt it down, gives a cleaner look.
 

·
Member
Joined
·
1,287 Posts
Weber Carb

Hey I'm getting my new weber in a week or so. Threads say to get shorter bolts, Where can I get them. I noticed I'm missing one of the bolts to begin with.
 

·
Registered
Joined
·
197 Posts
Discussion Starter · #8 ·
OK..finally got the carb installed at 10pm....so I've only had a little time to play with it, but these are the issues I've noticed. Only way it will start is if I pour a little gas down the carb. Then it'll fire and keep running IF you hold your foot on the gas and keep the rpms above 1500. If you let it go below that, it'll stall and it won't start back up until I dump a little more gas in it. I got the idle screw to open the butterflies so it would at least idle around 1500 or so, so I could get out of the car and mess with it. Even at 1500 it ran rough. When you floored it, it seemed to run fine. No hesitation or missing. So I played with the idle mixture screw. To tell you the truth, there was almost no difference if the screw was all the way in or out..except when I got it out alot it just stalled. That's when I cleaned up and came in the house, so that's all I've done to troubleshoot until tomorrow. Any ideas on what to check?

Other issues...I've seen mixed opinions on the heat shield. I left it off, because it looked like it blocked a little of the bigger throat, and I didn't want to cut the hole bigger. Has anyone had a problem with this heat shield removed. Also, the gas inlet points straight to the valve cover, so it is almost in the way of the heater hose coming from the thermostat. Can I get a brass elbow to take the place of the straight fitting? I got the electric choke model, cuz I didn't want to mess with the additional hassle of running water lines, when I took my solex off, it already had water lines going to that choke..guess I should've looked prior to buying.

Anyway, time for dinner and bed..any help would be appreciated.

Thanks,
 

·
Super Moderator
Joined
·
9,751 Posts
weber

bozkm;
As for the fuel inlet, you can unscrew the one on there, unscrew the cap on the opposite side and swap them. That way the inlet nipple is pointed away from the valve cover. This is one of the nice things about a weber. As for the hard starting and such, I'd make sure all your timing marks are aligned correctly. My sister's GT ran great, when she first got it, then switching to a weber, I found it used to have the A.I.R. pump and the PO didn't seal up the nozzles correctly and had to advance the timing to compensate for the extra air. So after correctly plugging all the leaks, and adjusting, the car ran well enough to scare the sh*t out of her. :D :D
 

·
Member
Joined
·
1,219 Posts
Which Weber did you buy? I had similar issues with a 32/36 on a GT and had to experiment with different idle jet sizes. There should be a significant change in the idle with no more than +/- 1/2 turn on the idle jet. Also make sure that you don't open the throttle stop screw more than 3 turns. If you do, the effect of idle mixture is minimal. When the valve timing is correct, the carb is jetted correctly, the timing & dwell are right, and there are no vacuum leaks, the settings should be

Idle stop screw - 1 to 3 turns (make sure the fast idle is not on)
Idle mixture screw - 2 turns +/- 1/2 turn

Weber 32/36 carbs often come with a size 50 idle mixture jet. Mine needed a 55 to get 950 RPM with the above settings.
 

·
Opel Tinkerer and Rescuer
Joined
·
7,517 Posts
One word.. Vacuum Leak.

Look for all the fittings and make sure ones not unplugged. Especially the one on the manifold behind the carb between the carb and the head.

What I have done to get a good seal is this combination:

1 - 1/8" Thick "fluffy" Paper Gasket
1b - Indian Head Shellac or Aircraft assembly glue (both at local auto stores)
2 - 1/4" Thick Felpro gasket with the nylon washers (Pinto gasket)
2b - Indian Head Shellac or Aircraft assembly glue (both at local auto stores)
3 - 1/8" Thick "fluffy" Paper Gasket

Those that only use the thin gaskets don't have enough material to get a good seal if you should have a slighty unsquare Weber bottom or intake face.

The thick Ford gasket, has those nylon washers that can keep you from tightening good enough for a perfect seal.

Using the three in combination give you a real tight seal and enough material to lock down the nuts and never have to worry again.

As for Jareds choice of using Bolts, thats not a bad option, but if you get them too long (but not so long you don't notice they are bottoming out). You can think you have everything tight and have leaks, so error on the side of being a little short. Its vital to use washers and lock washers. Also they also tend to back out more often than the studs/nut combination. So be sure to check thier tightness every so often and you may want to use a little low strength lock-tite.
 

·
Registered
Joined
·
197 Posts
Discussion Starter · #12 ·
I bought the 32/36 from top end performance. I didn't use any assembly glue when I put it together, I just put the gasket it came with on the manifold, then the spacer, the other gasket, carb. I will go by the auto store on the way home and try to reseal the carb. I don't recall seeing that vacuum hose your talking about, but I'll look.

I know I'll have to play with the jets, because I'm at 6000ft elevation, but the guys at Top End said it should run fine out of the box, I'd just loose a little power. Can the jets be changed while the carb is on, or do you have to remove the whole carb to change jets. I read somewhere, that I should probably try a smaller main jet.

Thanks,
 

·
Member
Joined
·
1,219 Posts
The idle jet can be changed while it's on the car; however, I would do that last. Check the dwell and timing first. Remember to remove the vacuum advance and retard hoses when adjusting the timing. It might seem obvious, but make sure you are using the right dwell scale on the meter. If it only has an 8 cylinder scale, double the number. Dwell should be 50 degrees +/- 2. Set the dwell first and then the timing as the dwell will affect timing. You shouldn't need to seal the gaskets on the carb, in fact some members of this site believe strongly that using a sealer is the wrong thing to do. If you still can't get an acceptable idle without opening the throttle up over 3 turns and the idle mixture over 2-1/2 turns, check for vacuum leaks. Temporarily plug the hose to the brake booster & automatic transmission, and check for vacuum leaks at the intake to head and exhaust manifold interfaces. If all this fails to get a proper idle speed you should check the valve timing. This only requires removing the valve cover. If you do need to rejet the idle, you only need to change the jet on the primary side of the Carb. The one that faces the passenger side fender.
 

·
Registered
Joined
·
197 Posts
Discussion Starter · #14 ·
OK, I feel like an idiot..but what is dwell?? I have timed many vehicles before with a timing light, but I have never adjusted or heard of "dwell".

This weber seems to be more pain than maybe it was worth. The car ran fine with the Solex, with just some hesitation. Hopefully, all will be well and worth it. Thanks for all the help.
 

·
Member
Joined
·
149 Posts
Dwell

bozkm said:
OK, I feel like an idiot..but what is dwell?? I have timed many vehicles before with a timing light, but I have never adjusted or heard of "dwell".

This weber seems to be more pain than maybe it was worth. The car ran fine with the Solex, with just some hesitation. Hopefully, all will be well and worth it. Thanks for all the help.
The dwell has nothing directly to do with the carburator. I can however help mask the true problem with an engine. Dwell is the amount of time the points stay closed and allow the coil to charge. With points the dwell should be set and checked periodically.

Darrin
 

·
Member
Joined
·
1,219 Posts
Dwell is a more accurate way to set point gap. If you don't have a dwell meter, simply do the best job you can of setting the point gap to .018". I didn't realize that your car was running well before you changed the carb. That would certainly point toward vacuum problems. Some year Opels had an extra vacuum connection on the Carb and I think an extra connection on the intake manifold. I would start by making sure that all vacuum connections are plugged. ( A piece of hose with the end plugged with an appropriate size screw or bolt will work) It think that some webers may have been shipped with an extra vacuum port open toward the firewall. You mentioned a spacer that you put on the base. I'm not familliar with that. The usual connection is made by placing a thin gasket on the intake manifold, placing the heat shield on that, placing a thicker gasket on the heat shield and then the Carb on top of that. Make sure the heat shield is oriented in the correct direction.
One other thing you might check.... Is the secondary throttle valve closed at an idle? The secondary is the one toward the driver side fender. It shouldn't begin to open until the throttle is at 2/3.
 

·
Old Opeler
Joined
·
5,564 Posts
bozkm said:
So since I have converted to electronic ignition, do I have to worry about dwell?
"Dwell" is a points thing - electronic ignition without points has it hard wired into the module. Just make sure your ignition timing is correct.
 

·
Registered
Joined
·
197 Posts
Discussion Starter · #19 ·
OK...just came in from the garage..I going to search real quick, cuz I think I remembered seeing something about this. If I put my hand over the carb, it runs fine, nice and smooth..take the hand away, it starts to "no want to run" even at 1500 rpms. I looked all over the manifold for vacuum lines. I got the one going to the valve cover (well the two, big one and small one), and the two going to the distributer..plus the ones going to the canister, which aren't a player anyway. Does this sound like a vaccum leak where the carb bolts in?? I bought some high temp gasket sealer, but haven't taken the carb off yet.

For the spacer, yes they sent me about a 1/4 inch black plastic spacer..is this not needed??
 

·
Member
Joined
·
149 Posts
Dwell & Electronic Ignition

If you converted to a pertronix there is s little clear piece of plastic in the kit. Use this to set the "point gap" between the hall effect sensor and the 'reluctor'. Everything else within the distributor will take care of itself.

Darrin
 
1 - 20 of 46 Posts
Top