Good evening, everyone. This is my first time on any forum, and I am in desperate need to help figure out what I am doing wrong.

Quick Background

Recently purchased a 1989 Coupe 1043cc. It had a poor choke to start with and once warm it ran at relatively high revs (No rev counter but i would say 1500 plus) and this continued for the duration.

I've recently replaced the head gasket (second attempt as I used the original bolts!!! School boy error but it's a learning curve).

I replaced the Carb flange as it was looking worn, but I managed to over tighten, and I think this pulled the nut out creating a gap. I put the old one back on as the car was running with this originally.

This was the start of the following issue:

Engine starts first time, but the choke valve starts a little wider than it should be, (increased revs from the start) and it continues to open till it's almost fully open at which point I knock it off quickly as it's screaming.

I've had the carb off the car and had a look at the choke. I'm not sure how to test the vacuum for the diaphragm. Tried adjusting screw (whilst car running) but it made no difference to the revs.

I have the haynes manual but I'm struggling to understand how to fix this issue. The car is my daily drive, which I love I need it to pick up my kids.

Hoping to get this sorted without paying for a mechanic with your help. This is a running project so hopefully I will have info that may help others especially when it comes to finding parts as I've had to replace a fair few parts.

 

Firstly, welcome to the forum and hopefully you can get some good advice here!
 

As this is a 1043cc, is it a Pierburg 1B3 or a Weber 32TLA carb?

 

Whichever it is, you need to ensure the carb flange is good and you’ve no air leaks, otherwise it’ll never run or idle correctly.

 

Which screw are you adjusting? on a 1B3 for example, there are two, one for basic throttle plate position and one for fine adjustment. The fine adjustment screw is large and will have a vacuum pipe fitted to it for the idle boost system.The basic throttle position screw should never be adjusted and should have a plastic seal attached to prevent this.

 

If it’s a 1B3, a correctly working choke should have the choke plate shut on pressing the accelerator pedal, quickly opening as the starts and engine warms up, assisted by a heating coil element within the housing itself.If the flap is opening but the revs are staying high then there’s a problem with the mechanism. There is a stepped cam that should be moved by the opening flap.

 

Again, if it’s a 1B3 there will be one pull down black diaphragm, all this does is open the choke flap a small amount when the engine starts to prevent over choking.

 

However, knowing which carb you have is essential, as adjusting methods vary.

 

If you have any photos of the carb and choke mechanism then that would be helpful.

 

 

 

Edited 6 October, 20223 yr by mk2tastic