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1963 AP5

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  1. I managed to rework the throttle cable hardware from the original carb so it would work with the Weber. It was a little fiddly but ended up working very well.
  2. The first task was to replace the factory carb. I pulled the plugs and it was obviously running super lean and on top of this i am sure that the vacuum secondaries weren't working. I couldn't find a rebuild kit for it so replacement seemed like the best option. I went for a 32/36 Weber because I have had good results with Weber's in the past and I find they are easy to configure and tune for different applications.
  3. Well I haven't been very good at keeping you all up to date with what's going on in my shed lately so I thought I should try a little harder and share this with you. A few weeks ago I spotted this 1982 Sigma SE on the side of the road in Ohope and decided that it had to be mine. It ran like crap, but it is very tidy and most importantly is rust free. I have been busy working on getting it running properly. The car was on LPG for many years and the factory carb was pretty much useless. I have fixed this problem by installing a 32/36 Weber and she runs sweet now. Photos and details to follow. Discuss the project and/or mock me for my ridiculous life choices here
  4. Oh dear, it's a sad day when the factory single barrel carb is genuinely the best option available. If you really do run out of ideas for the Weber flick me a message, maybe you can send it my way and I can pull it apart and have a look for ya. These carbs really shouldn't be that problematic but maybe there is something wrong with the way yours is put together. It is even possible that somebody messed around with it and got something wrong before you got your hands on it.
  5. Good trick using the old solenoid housing as a jet holder. It's great to see it running a whole lot better!
  6. Here you go. As shown on the pictures this is how my one works. The low speed jet and holder on the primary side is an aftermarket item that is designed to be used in place of either the two stage jet (on late model versions like mine) or the integrated solenoid/idle jet (on early versions like yours). It is physically much larger than the jet fitted to the secondary side and I have included a picture that shows the size for reference. On my carb the fuel supplied to the progression circuit (low speed circuit) must pass through this jet before it gets to the progression holes in the primary barrel. This is important because without this jet you simply can't tune the amount of fuel delivered to this fuel circuit. I think I made a mistake in the previous post and I got the direction of the fuel flow through the jet wrong, it actually enters through the end and exits through the holes in the side. I also took a photo of the carb body looking inside the area where the jet is installed. It does look suspiciously like a plunger sized hole but I am pretty sure your one should work just like mine and it will need a jet fitted in this location. As far as I am aware the only difference between the early model version like yours and the later model version fitted to my car is the separation of the fuel shut off solenoid and the idle jet. On the early version, the jet and solenoid were combined in one assembly. On the late model carbs they relocated the solenoid and changed it to a plunger type and fitted a fancy 2 stage idle jet in the low speed fuel circuit. I don't think the plunger type is supposed to be fitted to the early version of the carb. I also checked the jet size and it's a 60.
  7. No worries, will do. In the mean time this diagram may be useful to you. It describes how the fuel circuits in the primary barrel work. I think you are probably experiencing problems with the progression circuit. You can probably get it to idle OK but it will cough and splutter as you open the butterfly and the engine transitions to the point where it will run nicely on the main circuit. Sorry if I am adding way too much info but I will try to describe how this works. At idle with the throttle butterfly closed (well nearly closed) the fuel mixture is controlled by the idle mixture screw. As you open the butterfly the progression holes (I called them transition ports in by previous post) are uncovered and exposed to vacuum pulling fuel into the airstream. The amount of fuel delivered to the progression circuit is controlled by the low speed jet (idle jet). The progression circuit remains active up until about 3000 rpm and after that the engine will be running on the main circuit. Without the low speed jet metering the fuel in the primary progression circuit I think it will just pour fuel through the progression holes. Detailed photos of my carb to follow.
  8. This picture of the secondary side of the carb may help as well. The red arrow shows the fuel pathway inside the carb and you can see that the low speed jet is in the path of the fuel flow and controls the amount of fuel delivered. Pull out the secondary low speed jet and have a look at it, you will soon see how this works. The primary jet and the jet holder is physically larger than the one fitted on the secondary side but works exactly the same way. If you want to get really carried away have a look inside the primary barrel above the butterfly and you should see a row of small holes. These holes are called transition ports and this is where the fuel is flowing to. The fuel delivered to these transition ports must be precisely metered to ensure the correct air/fuel ratio is achieved and this is the purpose of the low speed jet.
  9. Something seems vey strange, the carb needs 4 fuel jets to work properly (plus the two air correction jets). You definitely need low speed jets for both the primary and secondary barrels. As far as I can tell, only 3 of the 4 fuel jets are fitted to your carb. Obviously the main jets are installed and the air jets as well, and there will be a low speed jet installed on the secondary barrel but you need a low speed jet (sometimes called an idle jet) on the primary side as well. From the factory your carb would have had a special solenoid that incorporated the low speed jet. The picture below shows how they work. Unmetered fuel enters through the holes in the side of the jet, the tapered end of the jet seats and seals against the carb body (this is the area that you described as a plunger sized hole). In your version of the carb this hole is not there to accommodate a plunger it is supposed to accept the tapered end of a fuel jet. Metered fuel exits via the calibrated orifice and ensures the correct amount of fuel is delivered to the primary low speed fuel circuit. Without this jet there will be way too much fuel delivered at low engine speeds (up to about 3000 RPM). Would it help if I took mine apart and snapped a few pictures for you?
  10. Hey any chance you can post a picture of exactly what is installed in this position on the carb. This is where the low speed fuel circuit jet is supposed to be installed. This jet is responsible for fuel metering from idle and remains active up until around 3000 RPM when the main jets progressively take over the fuel metering. I believe you should have either the integrated jet/solenoid assembly as shown in the above post (bottom pic) or the alternative solenoid delete option as fitted on my car.
  11. Alright I am sure we have nailed the issue, it seems highly likely that you are missing the jet for the primary low speed fuel circuit. This would certainly explain the problems you are having. This is probably not your fault as I expect the carb came with the incorrect solenoid assembly installed. All you need to do to fix it is throw the junk solenoid in the bin and replace it with one of these. https://www.weberperformance.com.au/product_info.php?cPath=6_268&products_id=1345 I would also purchase a selection of these https://www.weberperformance.com.au/product_info.php?cPath=6_268&products_id=631 I would grab a 55, 60 and 65 as you may need to experiment to see what suits best. When I tuned mine I used a wide band O2 sensor and a stand alone gauge. From memory the AF ratio on the gauge looked best with a 60 installed but the car seemed to run nicer and pull better under load with a 65 installed. I decided the seat of the pants dyno was telling the truth and went with the 65.
  12. Hey I have been thinking about your carb issue and a comment you made got me thinking. Can you post a pic of the fuel shut off solenoid fitted to your carb? I think there are two types of solenoid for the pre and post emission control carb. I think (but don't know) that the early pre emission control carb like yours is supposed to have a solenoid that has the low speed jet incorporated into the assembly as shown in the picture below. The later version like my carb has a separate low speed jet and the solenoid is a plunder type item as shown in the other pic. I think there is a chance that you have the wrong solenoid and if this is the case your carb will be running with no low speed jet and nil fuel metering on the primary barrel. If this is true I expect it would be running ridiculously rich. Have a look here https://www.progas.com.au/portfolio_category/carburettors-accessories/
  13. After a little digging through files on my old laptop I found the overhaul instructions for the carb. If all else fails we can always read the instructions.
  14. One more pic showing the other side of the carb. I have the throttle nudger blanked off on my carb, I think this is supposed to hold the throttle slightly open momentarily if the throttle is snapped shut suddenly to smooth things out. On some models it may also have been supplied vacuum as an idle up system for air con etc. The diaphragm can fail and cause a vacuum leak and most of the carb rebuild kits don't include this particular diaphragm. You don't need it so I just capped the rather large vacuum port.
  15. This may be useful to you to as well it shows the correct jets for the carb in stock form and this is exactly what I run in my car. These carbs are getting old and often people have messed around with them, changed jets for a particular application or drilled the jets. You can get tools for measuring the jets to ensure the orifice is the correct size, they are cheap and a very good investment.
  16. Second trap is the one that catches most people out. The vacuum port for the power valve is in an odd place on these carbs and some off the shelf adaptor plates will blank it off causing the engine to run on the power valve all the time and run very rich. The port is actually under the base plate and is not open to either of the carb barrels. The common adaptor plate available for a Holden 6 is a redline product designed for a 23/36 weber and there are a few problems with it when using a 34 ADM. The first one is it too low and the accelerator pump lever hits the adaptor. Secondly the barrels on a Weber 34 will not align with the adaptor. I chose to make an additional spacer to adapt the carb to the adaptor. Yes I know it seems silly to make and adaptor for the adaptor but it worked and solved both problems. You need to drill a vacuum port for the power valve in the adaptor plate and this port needs to also be drilled all the way through the stock manifold. If this port is omitted, vacuum will not be supplied to the power valve or the accelerator pump boost diaphragm and the carb simply wont work properly. If you look at the underside of the carb you will find the port (it might even be blocked with crud). The port is located between the primary and secondary bores and continues up through base and into a tube in the carb body. The tube also acts as a locating dowel and can sometimes become damaged and obstructed if the carb hasn't been assembled correctly at some stage in the past. Useful info on this can be found here http://www.mbs.id.au/tuning/Carburettors/Weber/34ADM.htm I wish I had documented this part of the process better and taken photos but I will try to show this with pics from the internet.
  17. Here is some info on the Weber 34 ADM carb as found on the XE/XF Falcon. This was a popular carb for retrofitting onto other vehicles but they are have a couple of little quirks that can cause problems if you are not aware of them. Firstly there is the 2 stage low speed jet solenoid. This was an emissions control system that allowed the engine to run with one jet size when cold (think it was a 70) and when the engine warmed up it switched to a smaller jet to reduce emissions (possibly a 55). Problem is they get old and the little diaphragm inside fails allowing fuel to flow from the primary low speed circuit through the failed solenoid and into the line that supplies vacuum to the system. this causes the engine to run super rich. But don't worry there is a solution. The products that solve the problem can be found here. https://www.weberperformance.com.au/product_info.php?cPath=6_268&products_id=631 https://www.weberperformance.com.au/product_info.php?cPath=6_268&products_id=1345 This is a larger jet holder that deletes the solenoid and the appropriate jets to go with it. You will need to mess around with the jets to find the right one for your engine. I think I ended up with a 60 or 65 in mine. Here is a picture of the system on the standard carb and another of the carb on my car with the system deleted. You will note that all the vacuum ports except the vacuum advance are simply capped off because all the emissions control stuff is gone (EGR etc).
  18. The Valiant never missed a beat all weekend, not bad for an old girl. I think the car was in better shape than I was at the end of the event.
  19. It was great to see this car on Gumboot Rally, I was very impressed with the quality of the engine build and there is no better way to prove reliability than running a GR!
  20. The boys have been having heaps of fun with the pedal car. We found that it has a big brother at Beach Hop so stopped for a photo.
  21. Beach Hop time! My boys even have a car this year.
  22. Unfortunately I can't make the Christmas get together, hope you all have a great time. MERRY CHRISTMAS OLDSCHOOL!!
  23. What diameter is the sender seal? This type of problem is common with old Valiant's and you can get a special reproduction seal that is a little thicker than original to sort it out. The Valiant ones are 3 inches diameter, if the Falcon ones are the same size (or very close) you may be able to use one of these. https://www.pentastarparts.com.au/store/index.php?l=product_detail&p=1931
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