18 replies to this topic

[big al]

hay everyone i have a 1275 with hif44 carb in my mayfair and she does not idle well its sitting between 1000 and 1500 rpm but does not sit steady iv tryed the timing off the dizzy but its still fluctuating up and down and i now have a flat spot has anyone had the same problem and how did you fix it or is there something up with my carb thats making it do this any help would be great 

[big al]

iv just been out in it there and she has no flat spot now and the idle has come down to between 900 and 1100 but still wont sit steady anyone any idea why shes fluctuating like this 

[old original]

possible air leak somewhere. Between carb & manifold and/or manifold & block is a usual suspect

[big al]

and will that cause it to hunt like that iv just had it on the ramp and the v piece is blowing at bit so il tink il check all seals around the mani and carb tomoro

[jaydee]

Air leak, check manifold nuts, breather pipes and the big servo vacuum hose, maybe the joint on the manifold is loose and leaks.

[big al]

Yeah im gonna have a good look tomorrow i think Il take the carb off and clean it would a new pin make any difference its the bdl pin for the hif44 carb

[KernowCooper]

BDL needle is a standard needle for a MG Metro, has the problem just started or been there for a while? air leak or incorrect mixture setting is where I'd be checking and wear in the spindle allowing air in and a inconsistent idle

[big al]

How can i check the spindle and its been lumpy since i got it a few weeks back so this is a still new to me

[KernowCooper]

Catch hold of the linkage on the side and feel for movement, where the cable pulls the cam open against the spring

[big al]

So if im looking into the bay its on the right side of the carb im gonna take the hole lot out tomorrow and have a look at all pipe work and i also noticed that the middle mani pipe has 2 little lumps of metal on ether side and don't let the bolts sit flush so this could be one of the problems so Il grind them down so everything sits flush

[KernowCooper]

Some of the cheaper manifolds are not made of the correct thickness material on the flanges so they are usually fitted using stepped washers to enable to centre bolt to pinch up the flange to gasket correctly and prevent leaks,

[big al]

Yeah but this one is the same thickness but wit the extra lumps of metal it doesn't sit right at all and the washers don't sit flat they sit at an angle so if i grind it down it shud make sit right so i can get them good an tight against the block

[KernowCooper]

Yeah but this one is the same thickness but wit the extra lumps of metal it doesn't sit right at all and the washers don't sit flat they sit at an angle so if i grind it down it shud make sit right so i can get them good an tight against the block

Ah I see that should sort it

[big al]

cheers for the help mate il let you know how i get on when im finished 

[big al]

I got the car into the garage to and took the carb off and took it apart and cleaned the hole lot and cleaned of the 2 half washers someone had weldedto the centre pipe for no reason and its still the same and wont idle right at all all pipes leading to the carb are fine and all nuts are as tight as they will go so has anyone got any more ideas of what it could be would it be the carb itself any help would be great because this has my head done in now lol