I have a 12 port head and HD6s. I will check for leak, but fairly sure that
there is no leak. Manifold leaks show their ill effect near idle - You set
the mixture right and it gets weak as You go up. Not in my case. The mixture
is ok on the full rev range, but when I floor it, it gets a bit weak (afr
14). No hesitation/missfire though, just not right. And only on the front
carb. The rear is ok.
Gergo
2011/7/1 Austin Healey <pajtamuvek at gmail.com>
>
>
> 2011/7/1 Alan Seigrist <healey.nut at gmail.com>
>
>> Gergo -
>>
>> The BN4 H4 carb has a two bolt mount which, if bolted too tight to the
>> head, can introduce vacuum leaks in and around the gaskets and spacers
>> and what not (too tight can result in warping of surfaces).
>>
>> The surfaces of all the various bits should be flat and clean, and the
>> nuts tightened with 30ish ft-lbs of torque only.
>>
>> Check that ...
>>
>> Alan
>>
>> On 7/1/11, Austin Healey <pajtamuvek at gmail.com> wrote:
>> > "It sounds to me like you have a vacuum leak somewhere. Remind me,
>> > what model/year do you have?"
>> >
>> > BN4 1958 - somehow skipped this question.
>> >
>> > 2011/6/30 Alan Seigrist <healey.nut at gmail.com>
>> >
>> >> It sounds to me like you have a vacuum leak somewhere. Remind me,
>> >> what model/year do you have?
>> >>
>> >> Alan
>> >>
>> >> On 6/30/11, Austin Healey <pajtamuvek at gmail.com> wrote:
>> >> > Hi Alan,
>> >> >
>> >> > Thanks! The exhaust is clean. Also checked the plugs, they are clean
>> and
>> >> not
>> >> > dark. The engines does not hesitates on acceleration, but has some
>> >> roughness
>> >> > below 2.5 if the throttle is held in position going on flat ground.
>> >> Especial
>> >> > can feel it is decelerating. Not that bad, but still present. The
>> carb
>> >> > is
>> >> > very sensitive on the mixture adjustment. As small as 1/4 turn can
>> make
>> >> > difference in reading and feel. Not something I am used to on mini
>> >> engines.
>> >> > I have bought a set of different advance springs. Though the advance
>> is
>> >> > working (each), I will experiment with the different springs tomorow.
>> >> >
>> >> > Gergo
>> >> >
>> >> > 2011/6/29 Alan Seigrist <healey.nut at gmail.com>
>> >> >
>> >> >> Gergo -
>> >> >>
>> >> >> The trick is the exhaust should not have a "smell" and should not
>> show
>> >> >> smoke. If it smells rich or shows smoke, the mixture is off. Check
>> >> >> timing and make sure advance weights are operating and vacuum
>> advance
>> >> >> lines are hooked up and operating.
>> >> >>
>> >> >> Let is know how it is going.
>> >> >>
>> >> >> Alan
>> >> >>
>> >> >>
>> >> >> On 6/29/11, Austin Healey <pajtamuvek at gmail.com> wrote:
>> >> >> > Thanks everybody for the knd words!
>> >> >> > I did my first Healey-miles today. Tha car is running well soo
>> far. A
>> >> >> little
>> >> >> > oil from the valve cover gasket and the oil filter case, but no
>> >> horror.
>> >> >> > After a few joyfull miles came the rain and stopped the fun. Such
>> is
>> >> >> life.
>> >> >> > I have some questions though. When shall I retorque the head?
>> >> >> > I have started to adjust the carbs with a WBO. Starange, but the
>> car
>> >> is
>> >> >> not
>> >> >> > realy willing to run on afr 1.47. For proper smooth running it
>> needs
>> >> >> > slightly rich mixture of about afr 12.5-13.5. Is it normal? If I
>> >> weaken
>> >> >> the
>> >> >> > mixture it begings to run rough. I measure the afr at each
>> downpipe
>> >> just
>> >> >> > below the manifold. The timing has little impact on it.
>> >> >> >
>> >> >> > Gergo
>> >> >> >
>> >> >> > PS: Healey forever.
>> >> >> >
>> >> >>
>> >> >> --
>> >> >> Sent from my mobile device
>> >> >>
>> >> >
>> >>
>> >> --
>> >> Sent from my mobile device
>> >>
>> >
>>
>> --
>> Sent from my mobile device
|