2 replies to this topic

[Bazooka Joe]

I have a 1275 A+ auto engine and box in the car out of a Metro; the guy I got the car off also put on a cast iron Cooper exhaust and inlet manifold, HIF 44 carb and Cooper carb exhaust, and it was ok for a couple of yearsbut recently I have been having poor running issues, and was advised it was the choke seals and to renew them, which I did. (Thanks for the advice guys - they were split). At the same time I put on a Minisport cone airfilter and a couple of months ago a 2" stainless steel Play Mini exhaust. So far, so good, however it's still running rough so I took it to a garage here to set the mixture up properly and he said there wasn't enough fuel getting in, it was running very weak, and there wasn't enough adjustement to enrichen it further. (I have been driving round on the choke for weeks just to keep it running). So my question is, can just putting on a 2" single box exhaust and freeflow airfilter cause the mixture to weaken that much? The current needle is a BEJ, and I used a proper SU rebuild kit for it, including a new jet (but no needle).

I put the old filter back on yesterday and it's running loads better, so I'm guessing it did weaken the mixture off the scale so to speak.

[Vipernoir]

Changing the filter and exhaust will require a session on the rolling road to set the fuelling up properly - merely twiddling the mixture screw is not adequate, and I would hope the garage who tried it didn't charge you as they should have known better.

 

Having said that, it does sound as if you have a monster airleak somewhere for it to be that lean.

[Bazooka Joe]

He is just a normal garage rather than a rolling road, so he just used the mixture thing on the exhaust I'm assuming. I'm currently in Germany so finding a rolling road is proving problematic to me! I also assume he would have tested for an air leak but you never know; I did spray some carb cleaner on it recently and it didn't make much of a difference but to be honest that was when it was running really rough. I changed the spindle and choke seals a couple of weeks ago but the ones in the SU kit whilst fitting tight on the shaft itself, were smaller in diameter than the ones I took off and so didn't go to the edge of the recess they sit in. I might try to see again if there is an air leak and pay more attention this time!