I've installed a Weber 32 carb today. Now I'm stuck. I crossed my fingers, pulled the choke out full and turned the key. The engine roared into life and revs at impressive speed. But if I put in the choke any more than a little bit, it immediately stalls. It won't drop revs to anywhere near idle speed before stalling.
So something is blocked inside, I guess. I tried keeping the throttle open while taking the choke off, but that doesn't work wither and it still stalls out.
I'm a bit of a novice. Where should I be squirting the carb cleaner, or should I be poking somewhere with a paperclip?
Where the carb fits to the manifold there is a drilling in the bottom flange of the carb. It is easy to block this with the gasket when fitting, check if this is clear and if needed cut a notch out of the gasket to give the drilling a clear path to the inside of the manifold. Obviously while still maintaining a seal to the outside. In terms of jet cleaning, take the top of the carb and there are two jets in the bottom of the float chamber. You can remove these with a screwdriver and check they are clear. Then spray carb cleaner down all the drillings.
Thanks Ady, I stormed off to try all the above. After a bit of internet reading, advice was that there might be an air leak at the carb or manifold gasket, so that air could get in even with the choke flap fully closed, so I re-gasketed and Holdited before pulling the jets and using the carb cleaner. I cleverly attached a tube to the aerosol nozzle for more directional squirt power, stuck the tube against a tiny hole and pressed, and got a back blast of carb cleaner straight into my left eye. For a long seeming second, nothing happened, then a searing burning sensation. Took me a while to get back to carb cleaning and it still stings a bit. Anyway, all done, back together, fired it up, just the same problem as before.
I've got some larger jets for this carb which I'll try, because it would seem to be a weak mixture problem but I don't expect that's the problem (I'm guessing that the low speed circuit is plugged in some place I'm not going to find). Is it that this carb would not work with a 700cc?
Essentially, the current position is that I can keep the car running using the choke as if it was the accelerator but it is over-revving. If I open the choke flap more than a quarter, it dies. Oh please save me from the Zenith!
I think the carb will defiantly work. it's just a case of getting the carb fitted and set right. Do you know that the carb is in good condition? If it is old or has been in storage for too long it may need rebuilding with fresh gaskets and diaphragms etc. rebuild kits are easily available. It could easily be an air leek. To check for air leeks, spray carb cleaner, WD40 or anything else you have to hand, around the gaskets with the engine running. If things temporarily improve there is an air leek. I would avoid the use of any gasket sealant on a carb, because of the risk of blocking things.
Have a fiddle with the mixture screw, This is below and to the right of the throttle linkage. If the protective cover is still in place, it will look like an aluminium tube sticking out, and down the tube will be a brass screw head. If the cover has previously been removed, you will just see a brass screw. Remove the screw completely and pull off the cover for easier adjustment. screw it in and out with the engine running, and see what happens.
Have you got the idle solenoid fitted to your carb? It is fitted to most but not all ICH carbs. If you have one it must be connected to a positive power supply. There is another jet under this so again worth removing, cleaning the jet and checking it is not blocked.
Sorry about the random selection of things to check, it's just the way they are falling out of my head.
Yep the idle solenoid is there and does click. I didn't know there was anything like a jet inside it, I'll take a look. I was wondering what it was supposed to do, as disconnecting the power doesn't seem to make any difference to my problem. This carb is a 20 quid EB*y special, so it may have gasket rot all over. I'm still looking suspiciously at the manifold as the motor wasn't running well with the zenith and was overheating, which it didn't used to do (before I fitted the simonbbc elec ignition, previously chief overheating suspect). I'll get a kit and overhaul it with my remaining good eye, and report back.
I found the emulsion tube was half plugged by a white chalky substance, blocking all but the topmost holes. Now the engine runs more normally, but the slow running circuit is blocked. I can hold it running at just above normal idle speed, but with the butterfly closed it stalls. So, waiting for the overhaul kit and expecting more munge in unexpected places. I wonder how it got there and what it is? Thanks ady for the encouragement that this setup should work. Any discouraging words earlier this week & I would have binned this carb for something more expensive.
Why don't you like the Zenith ? We do a lot of repairs to mowers etc and have had similar problems with a lot of machines this year , seems worse if they have stood and not been used for a while. The best solution is to find someone who has a sonic tank that you can put the carb in (many larger garden machinery/farm machinery companies do because of this problem). It works like magic , so good we are going to get one. We have had several machines where we cleaned and soaked them in carb cleaner , but they still either would not start or would only run on choke the same as your Bug . It seems that the rubbish petrol that is now available seems to coat the inside with something similar to varnish which you cannot see and carb or brake cleaner will not shift even with a good overnight soak. The sonic tank will clean it up like new .
I'm on my third Zenith since 1982, and main complaint is hard starting from both cold and hot.
Now, after a rebuild and more study, I have the 32ICH on and running. The car now starts without choke or with just seconds of a little choke.
The final problem was a clogged slow running jet. I thought the solenoid was at fault, as with jet removed, it didn't seem to retract under current. However, minutes away from snipping off the end of the rod and just living without it, I realised that the rod of the solenoid is slightly pushed in by the jet, and it does retract as long as it isn't asked to do so from full extension. This paragraph will sound like nonsense to anyone who hasn't tested a carb solenoid in their lives.
On to the next job, changing the diff gear for the B axle internals, aa outlined on the World of Reliant board. I'm going to attempt this simply be removing the rear able, undoing the diff housing bolts and pulling into two halves with half shafts still in place. There is bound to be a snag in doing this, but I'm committed now. Will report later.