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New coil came in. I swapped it out with the old one, which was much harder than it should have been trying to get the bolts that hold the coil in place back in. Now the car won't even fire. I haven't checked for spark yet -- ran out of time. The car just cranks and nothing. I got the Pertronix Flamethrower, which is specifically supposed to work with Pertronix ignitions. The old coil was a Lucas coil. The swap was straightforward -- put the black cable on the negative terminal, put the red cable and the cable going to the generator on the positive terminal. I can't figure out what has gone wrong, unless the new coil is bad.
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Carb Issues
- Thread starter SaxMan
- Start date
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After sleeping on it. I went back, rechecked the connections to the coil and the car fired up. Tach wandering has abated, but the mix is still off. Probably won't be able to get back to it until Saturday morning. I'm beginning to think this could be a case of bad gas, too.
Finally got the old girl running right. The coil helped, a new tank of gas helped. I decided to skip the Gunson and just use the screwdriver test to adjust the mixture (raising the piston just barely). and found the car was too lean. Once I sweetened the mixture everything started returning to normal. The idle is still not perfect, but the car revs well through the entire RPM range. I may do a little bit more tweaking once the weather warms, but for now, I'm calling it done.
Took the car to work today. It ran fine, except the idle was up at 1500 rpm. No matter what I did, the lowest I could get the idle down to was about 11 - 1200 rpm with the idle screws nearly backed out completely. Thoughts? Mixture too rich now? I still get an occasional "pop" under deceleration.
dklawson
Yoda
Offline
Go through the carb balancing again making sure that the choke linkage is 100% lose.
Whenever I have seen an idle that cannot be adjusted down it has been because the choke linkage was interfering with the jet adjustment OR the problem surfaced after a complete carb rebuild where the butterflys were put in wrong and held the carb open more than normal at idle.
Whenever I have seen an idle that cannot be adjusted down it has been because the choke linkage was interfering with the jet adjustment OR the problem surfaced after a complete carb rebuild where the butterflys were put in wrong and held the carb open more than normal at idle.
I'm thinking it could be a leak. The gasket between the carb and heat shield on the rear carb had a tear, but I thought I set it properly.
Either way, I'm thinking I need to pull the carbs, check everything over, put it all back together. It seems like there has to be something obvious that I'm missing.
Either way, I'm thinking I need to pull the carbs, check everything over, put it all back together. It seems like there has to be something obvious that I'm missing.
Ding! Ding! We have a winner.
When I put the carbs back together, the piece that links the choke on the two carbs wasn't in the hole on the rear carb. Loosened up the carbs, reset the choke link, tightened it back up, and then realized I put the link back in upside down this time. Reset it again. This time it was fine, but when I opened the choke, the jet on the rear carb was going further out than the front carb. It was at this point I discovered what those nuts on the choke link (and the throttle link) actually do. After some tweaking, I got the two chokes opening in perfect synchronization.
I also replaced the rear gasket, which had a tear, since I already had the carbs loosened up. Also rechecked the oil breather connections to eliminate the possibility of vacuum leaks. No test start or test drive tonight. In cold weather, the exhaust gets sucked back into the house, even with the garage open and a fan blowing. I'll try in the morning.
Looks like I'll have everything ready to go just in time for the 12 inches of snow we're supposed to get on Tuesday, which will likely keep the Sprite off the road for at least the next two weeks.
Didn't you guys just have 70 degree weather a couple of weeks ago?
77 degrees 10 days ago. 67 degrees last Wednesday.
Worked on the car some more. It's running okay. I have a bit of a stumble around 1800 rpm, but above and below it's fine -- runs up really well past 2000 rpm. I think I've still got a leak somewhere and bought some starter fluid. When I hit the suspected area with it, the engine will speed up if I have a leak?
Typically I use the starter fluid trick to find a vacuum leak that is causing the engine to run rough and idle poorly, but yes, the engine will speed up if you spray starter fluid around the connections and where the butterfly shafts go through the carb body if you have an area that is sucking air in. Man I would kill for 70 degrees right now! I can't remember the last time the sun came out here! It's been pouring rain since I can't remember when. Good thing my car is broken anyway for the fuel pump issue I spoke about earlier....otherwise i'd have another reason to complain about the weather.
Good luck
Mark
Good luck
Mark
Well, the blizzard never materialized as advertised. We got three, maybe four inches of a slushy/icy mix. Roads are now clear, but they lay down enough salt that the Sprite would disintegrate immediately if subjected to it. I'll have to wait for warmer weather and a good rain to wash this crap away.
Wish I could ship you some of the rain you're looking for:confusion:.
They put enough salt on out here that it will probably take till June to wash it off. When I was young South Dakota refused to use salt and only sanded. If you wanted a good solid older car all you had to do was to drive towards the middle of the state where you knew the cars hadn't got any salt. The differences were amazing. Now the roads are more likely to be white with salt than white with snow and car's rot away in just a few years. Who really gains from this....I'm saying big insurance!
Kurt
Kurt
Don't know if the insurance companies benefit -- but the automakers certainly do. Probably a lot of municipalities now in "CYA" mode out of fear of being sued if someone slips, falls, or their car goes out of control, so they dump as much of the crap on the streets to make sure they can say they did their due diligence.
It's pretty rough on bicycles, too. Even though all my bikes are aluminum frames, some of the componentry is not. Some of the abrasives used are sharp enough to puncture a bicycle tire, as I've learned. My road bike sits alongside the Sprite to wait for clear roads, too.
It's pretty rough on bicycles, too. Even though all my bikes are aluminum frames, some of the componentry is not. Some of the abrasives used are sharp enough to puncture a bicycle tire, as I've learned. My road bike sits alongside the Sprite to wait for clear roads, too.
D
Deleted member 8987
Guest
Guest
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How far back in this thread did I mention one of the signs of a vacuum leak is hunting idle (which you had). High idle is sometimes secondary, and if a gasket has failed further than it was, would be right.
Spray carb cleaner with a wand around the bases (ignore shaft) will cause change in idle and you should find it.
Well, I thought I found the source of the leak: There is air leaking through the throttle shaft that holds the butterfly in place. When I had the engine and pushed up the piston, I noticed fuel vapor coming out of the left side of the front carburetor where the throttle shaft resides. I reasoned that if something was coming out, it could also let something in. Sure enough, with the engine on and using a tube, you could hear the hiss of air being sucked into the throttle shaft opening. As far as I can tell, though, there are no washers or anything else like that to keep air from being sucked into the the throttle shaft.
I'm really leaning towards letting another set of eyes look at this.
I'm really leaning towards letting another set of eyes look at this.
dklawson
Yoda
Offline
Throttle shafts and the carb bodies do wear. For years I have heard people talk about "reaming carb bushings" but none of the cars I have worked on have had SUs with bushings.
I believe Joe Curto and Moss stock oversized throttle shafts to minimize the gaps that can be fitted to close off most of the gap in a worn carb body.
I believe Joe Curto and Moss stock oversized throttle shafts to minimize the gaps that can be fitted to close off most of the gap in a worn carb body.
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