FridgeFreezer Posted August 20, 2014 Share Posted August 20, 2014 As some of you may know, I dislike carbs. Unfortunately our latest purchase has them and I don't have the time to megasquirt it just yet. Also unfortunately, it runs like a dog* and we need to drive it around a bit in the meantime. So, I'd like to go over the basics of setting it up somewhere near properly without ending up up to my eyeballs in tiny springs and petrol or buying loads of new bits when I'm only going to pull the blessed things off a few months down the line. The engine bay currently looks very much like this, but now minus the LPG kit: So, what do I do / check / adjust / reset / hit with a hammer to bring it somewhere near back into line with minimal dismantlement? * = OK, more like a dog than expected from carbs & dizzy Quote Link to comment Share on other sites More sharing options...
Chicken Drumstick Posted August 20, 2014 Share Posted August 20, 2014 It may be of no help at all. But I'd first want to check/sort out the ignition timing side of things. Electronic ignition kits aren't all that pricey and at least you know that is no longer an issue. As for the carbs, many people seems to claim to know how to set them up, but my experience has shown that this often isn't the case. And the people claiming to know either fail or are just lucky. Find someone who really does know how to set them up and it'll be worth it. A friend has an CCV motor on carbs, it went through 4/5 people who all claimed to know how to set them up. All failed, despite claiming it was running better. £70 to an old school mobile engine tuner and job was done and it ran sweet as anything. Nothing was wrong with the carbs either, just the settings others had messed about with. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted August 20, 2014 Share Posted August 20, 2014 Good luck FF Seriously, you will need it Actually, as you have SU's they are pretty simple beasts. I would take the tops off, and make sure everything is moving freely, the needles not too worn, and clean any browness away with petrol and a rag, NOT an abrasive. Refit and top the dashpots up with 20w50 and see how she runs then. Unless there is something really wrong with the floats that is all they normally require as far as maintenance -but even if you do take them off the bottom halves are very simple too, nothing like even the old horrid series carb which is far too complex for it's own good! Of course electrics are never a strong point on a RV8, but I am sure you know this anyways Mixture is adjusted by the nut underneath, or if you have the very late carbs fitted, by a big cross head screw. Then you should balance them... Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted August 20, 2014 Author Share Posted August 20, 2014 Bowie - do you mean take the cast dome top off or just unscrew the dashpot filler top thingy? If I remove the dome, will I need to replace a gasket or owt? My limited experience with carbs is it's very easy to bu&&er them up just by looking at them, so I'd rather avoid disturbing anything I don't have to! Oh and yes the ignition system probably isn't tip-top either but I re-set the timing when I removed the LPG ignition amp and checked the vac advance so not sure what else can reasonably be done without buying new bits. Quote Link to comment Share on other sites More sharing options...
steve b Posted August 20, 2014 Share Posted August 20, 2014 Hi John while the top is off the carbs bring the main jet up to level with the venturi on each using the mixture screw . I do this using the end of a steel rule on the flat bit of the venturi over the jet and then wind it up to touch . then lower it 1 1/2 turns of the screw as a base point to run it and fine tune. Check the needles are set in the same circlip groove on both pistons as well. Pop the link rod off one carb and loosen the throttle cable , then undo the butterfly stop screw until it is off the butterfly , then bring back in touch with the pad on each , then clockwise 1 1/2 turns as a base point . adjust the link rod to fit back without it opening either butterfly and no slack as the butterflys open , then adjust throttle to suit When the settings are right the piston lift pin should bring revs up slightly and then settle down again Set the points with a dwell gauge if you have one 26-28deg iirc and make sure the gap adjuster is tight to turn , the little plastic nut( under the baseplate) it goes thru can get loose hope that's of some use to you cheers Steveb Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted August 20, 2014 Share Posted August 20, 2014 Yes, take the complete ali top off, 3 flat head screws, there is only one large spring in there and the piston, nothing scary at all. No gasket, these are properly made SUs that rely on machined surfaces for a seal Ignition side is just check condition and replace if suspect. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted August 21, 2014 Author Share Posted August 21, 2014 replace if suspect. Ha, I suspect all of it, and in due course it's all going to get replaced! Quote Link to comment Share on other sites More sharing options...
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