11 replies to this topic

[ohsuchislife]

Ok peeps .. hope you can help .. banging my head against the wall now .. just put a HIF 44 carb on a 1275GT engine with LCB and 1.75 complete ehaust .. think its a standard head .. good inlet manafold .. not heating it .. now the problem .. start the engine idles lovely .. revs lovely .. no flat spots etc .. now as i pull away .. i get a slight flat spot put my foot down and it goes away and pulls great .. now i get to 50 - 60 mph and the carb seems to nslutter and loose power again put my foot down and again can pull through it .. it has a BDL needle .. the carb is second hand .. goinmg to put the HS4 back on tomorrow to see if the manifold etc is ok .. no air leaks .. got some different needles coming next week and a red spring .. is this me or does this seem like a week mixture .. or the carb could be US .. or a ton of *melon* in it .. gave it a good clean ..

any ideas .. and your thoughts

[newdawn1st]

When you changed car to the above parts was the setup changed to suit? ie ignition timing, fueling etc?

[ohsuchislife]

no didnt touch the settings ... didnt think about that ... timing is ok .. or should i retard it .. etc .. took the plugs out they seem lighter grey brown .. running out of ideas now .. gave the idle a bit of the rich setting .. WD40 the inlet manifold no leaks etc

[newdawn1st]

This will require a setup but sorry beyond me, people on here will be able to help you with the initial setup but sounds like your pretty close, may be something in the FAQ. Sounds like you essentially have put on a 'stage 1' kit so a rolling road might be best.

or was the carb the only change? might just be the needle if so.

[ohsuchislife]

thanks again mate ... i might retard the dizzy .. a bit .. looks like the carb 1990 coopers are running at 5 BTDC .. might give that a go .. does sound im close ..

[shellspeed]

Had the same problem on a friends SPI when we put a HIF44 on . Changed the needle and it ran like a dream . Cannot remember which needle it was but the replacement was a standard MG metro needle if anyone can tell you what that is .

Hope that helps

J

[bmcecosse]

Start with a BDL.

[ohsuchislife]

thats is whats in it now .. a BDL .. going to do a basic set-up tomorrow .. then try a few needles to see if that inproves it .. ..

[bmcecosse]

The BDL will be fine (it may not be exactly perfect - but it will run ok!) - better look elsewhere!

Edited by bmcecosse, 03 October 2009 - 07:33 PM.

[ohsuchislife]

this is all getting strange now .. just put back on the HS4 carb and it does the same but worse .. mmmmmm me thinking now .. could it be the inlet manifold not seated right or leaking .. the car ran great with the standard exhaust and manifold with the HS4 carb .. now runs shat ... looks like im going to have to take it all off anf replace the manifold gasket and check manifold for leaks or cracks .. check timing .. etc etc .. oh the joys of motoring ... looks like me Vespa might get a airing

[lawnmowercrap]

this is all getting strange now .. just put back on the HS4 carb and it does the same but worse .. mmmmmm me thinking now .. could it be the inlet manifold not seated right or leaking .. the car ran great with the standard exhaust and manifold with the HS4 carb .. now runs shat ... looks like im going to have to take it all off anf replace the manifold gasket and check manifold for leaks or cracks .. check timing .. etc etc .. oh the joys of motoring ... looks like me Vespa might get a airing

When the cars running try to squirt some WD under the inlet. Ive had air leaks under the inlet before

[ohsuchislife]

looks like ive found the problem .. it was the inlet manifold .. the vacuum for the sevo was not seating .. and the manifold nuts were slighty loose so new gasket and she runs ok .. just need to tune the carb ... i think a new needle would not go a miss ... looks worn ..

thanks again for all your replys