28if Cab Wanted (or jets)

[mike4gtl]

Hi folks, i attempted to drill me jets out as i thought my car was running too lean (vac advance pipe not leaking) but it went wrong and now it over fuels. Can anyone help?

Thanks michael

 

[Bobble]

silly boy, i'm not sure but i will have a look tomorrow and let you know.

 

[Cornish4]

Bad luck Michael. It's only the main jet you need to enlarge to slightly richen the mixture. As standard it's .9mm and it only needs to be opened up to 1mm to do the trick. If Bobble or some other kind soul out there has a jet you can save the day.

Regards Brian.

 

[mike4gtl]

I enlarged it to 1mm and it responded better so I went bigger. I also drilled out the long brass pick up tube in the top part of the carb. As a result I have excellent pick up response but it judders from running rich and is now much slower. It also doesn't like choke.

 

[MarieR4]

I found my carb pretty sensitive when exchanging parts across some models even if they look almost the same. I had similar effects when mouting on my car's (GTL) carb lower part the carb top of an F6 which has a second long brass pick up tube. I only used carefully an awl on the main jet to make it a somewhat larger as Brian suggested above. This did the trick. The brass pick up tubes are pretty easy to damage btw. When changing parts between different carbs be careful to mount the correct float needle, guess there are two. If they do not match in their position, the carb gets flooded with fuel and same with the engine. With the wrong one the intake manifold can get easily flooded of fuel then when decelerating or going downhill although the needle position varies only by .5 mm or so. At least this was my experience when my carb broke in France and I needed to build a new one from two old from the scrapyard.

 

[Cornish4]

Hello Mike, hmm, as I mentioned it is only the main jet that needs enlarging to 1mm to do the trick and make the engine run as it should when hot with the choke in. I know we like try to squeeze a bit more power out of our engines if we can, and sometimes it works, and sometimes not, that's the "fun" with our hobby isn't it?

 

[mike4gtl]

Luckily a forum member is saving the day! Amazingly I was getting 400 kilometres to a tank full before I medaled with it and now only 300. That's a big difference. I'd sooner have the fuel economy these days