Carb problem or something else

[Dean Kuan]

Hi Guys,
my gt6 seems to be running only on one carb(carb 1 the one towards the gearbox) when idling. there is only hissing sound coming from that particular one. so i open up the air filter and have a look. Found out that there is totally no suction power from carb2.  try to cover up the carb 1 with hand, the engine dies, nothing happen doing the same thing to carb 2.

Besides both dash port can comes down when it push up but seems that carb 1 is way smoother. tested the vacuum, it reads 20inhg. also found out that when on throttle, carb2 seems to open slower than carb 1.

My car been lack of power, bit hard to reach 100km/h. dunno what to do now so seek for help and advice. Im currently running on the emmission control carb 1.5 cdse. 2.3psi fuelpump of a honda 1.6. the carb been serviced with new, butterfly, linkage and diaphrams.

will try to shoot a video and post it here soon.


Hope my car will be healthy.

again from,
Dean
(gt6 borneo)

[junkuser]

Try disconnecting the linkage between the carbies and adjusting mixture and idling speed on each independently, then reconnect.

[rotoflex]

I agree, disconnect the linkage between the carbs and see if the carbs can be adjusted to draw equally.

[greenbonnie]

before you change carb settings. as my friend had exactly the same problem on his spitfire.turn out he had air leak at the manifold. the four brange he got from rimmers. had a distorted mounting. worth checking if you have a four branch manifold.  

[Dean Kuan]

Thanks guys,
So meaning that one carb doesnt run could be the leaks of manifold?

Dean

[junkuser]

No.   It means one throttle valve is closed.

Depending on the type of linkage joining the throttle spindles (degree of torsional flexibility), it is possible that the non-breathing carburetor will come to life at idle simply by screwing in the idle adjusting screw but still best to disconnect and  adjust each carburetor independently at idle.

Of course the problem could be that the linkage between the spindles is not holding but still that carburetor should be hissing if adjusted correctly.

[Dean Kuan]

Hi Guys,
the problem still there no matter how i try. this is a video. Thanks

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Dean

[Dean Kuan]

http://www.youtube.com/watch?v=3nSMKCUpov0

[RedRooster]

Can you see any fuel atomisation on the front carb?

[rotoflex]

Do you have instruction manuals for rebuilding & adjusting the carbs?
I ask because they often refer to lifting the piston, but only a slight distance (like a couple of millimeters).

Does it seem like on one of the pistons adjusting with the mixture tool has no effect?  If that is the case, on that carb you can unscrew the four screws which hold the top cover on, completely withdraw the piston & the long spring.  Then while you have it out, you can see if the adjustment tool is moving the needle up & down.  It is possible to lose adjustment there, and then you will have to take it apart and put it back together as at
http://www.bowtie6.com/CarbRepair/index.htm

Your oil leak from the front plate looks pretty bad.  You may be at the point of either living with it, or pulling the engine out to repair/replace that component.

[Dean Kuan]

Thanks guys, will take out the carb and do it again :) we'll see how it goes. Im taking off the front plate again as well. Hopefully can be solved.

Dean :)

[rotoflex]

Someone also mentioned that it is important to use the correct length bolts (actually cheese-head screws) going up into the front plate, because it they're too long they will move the block out of position.