Help with fitting new carb. Please!!!!!!!!
You definately have to get this sorted out Dean, I had a similar problem and lost the girl because of it......that was another life though :-)
You've done the right thing so far. The fast idle is as a result of either the throttle cable being too tight or the idle speed set too high. Which as it's a new carb is probably the latter.
As you look down on the carb body you can see the square outline of the carb body from above. In the bottom right hand corner of the body when viewed from above, the corner nearest to the front n/s wheel, there is a screw fitted vertically downwards into the body. You should be able to see the bottom of the screw where it comes back out of the underside of the flange on the body and it's tip, which presses down onto the throttle linkage. This screw becomes the return limit stop for the throttle arm and is used to set the idle speed. As you unscrew that screw the revs will come down.
It may be that you have set your throttle cable to have very little slack in it with the throttle in the faster position and now as you unscrew the screw the throttle cable stops the the throttle linkage returning properly, so slacken off the throttle cable clamp when you do this, and may as well check for any interference from the choke mechanism just behind it too.
If, as you undo the idle screw, the speed doesn't drop AND the cables are free then there is an adjustment on the choke linkage which can affect engine speed. there's a small adjusting screw on the choke linkage arm whcih opens the main throttle valve as the ammount of choke being set is increased. This adjusting screw can be turned as easily as the main idle adjust screw.
Being a new carb you should have got a new needle fitted suitable for your car. If not you will need to change over the needle from the original carb....take out the three screws holding the dashpot down and carefull lift out the dashpot. the needle is held in by one horizontal machine screw. If you have the correct needle fitted then you have to set the mixture next. The Haynes manual explains doing this I think, but it's simply a case of turning the mixture adjusting screw to the rear of the carb just above the float bowl area, and just below where the fuel supply pipe enters the body. Screwing it in richens the mixture and screwing it out leans the mixture.
Why did the engine stabiliser bar break ? The only time I have had that break was when rigid polythene bushes were fitted. the first time the stab bar broke, and then after refitting the bushes it broke off the mounting lugs from the bulkhead. Changed back to rubber and never had another problem. Changing rubber bushes at 6 months or so isn't a great bugbear, and you get down around the engine at the saem time and stand to spot other problems too.
So the spare pipes and holes. the spare hole on your water heated manifold is probably small. It is for the vacuum advance going to the distributor. You have already connected that to the vacuum takeoff on the carb body close to the manifold mounting flange. You can either cap it off in a suitable manner or, pull out the copper pipe, then tap the hole and fit a screw.
I called it a water heated manifold as a opposed to water cooled, because the water pipe is desined to allow the manifold to heat up quickly on cold days and prevent icing inside. Original manifolds had a 'hot spot' where the echaust and inlet were cast together and so the hot exhaust manifold heated the inlet manifold soon aftre starting up. Because you have lost this the hot water does the same thing. A hot inlet manifold makes the fuel vapourise more, which is good for combustion. There is an argument that leaving the water heating off makes the inlet mainfold colder and alllows more air to be drawn in, because it will be colder. I have mine off, but I don't know if the differrence will be noticeable on normal road going cars.
The last pipe is the fuel overflow pipe. If you have car with 2 fuel tank pipes then the unused one is the return pipe. Otherwise your old HS4 should have had an overflow pipe fitted, in which case connect the HIF pipe to that tube. If you don' thave an overflow at all then make one. As you can see should the overflow pipe start venting fuel it will dribble straight down onto a hot exhaust pipe ! You only need a piece of plastic tubing to direct the overflow off to the nearside, behind the rear subframe mounting or anywhere clear of the exhaust pipe.
Posted: Sep 03, 2006 12:03 PM