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once more into the breach ...er carbs

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Woodie

Woodie

Jedi Warrior
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Ok last week I got the timing right on my 1275, 10 degrees BTDC. The idle is now steady at 1000, but the car seems to lack power, and on these cool mornings only seems to run without hestitation when accelerating. One other symptom is that when cool (ie the temp guage is not quite halfway to N) it occassionally backfires in the carb. Later in the day when driving home there is more burble and pipe backfire when I let off the gas say in 4th or 3rd and coast to slow down in traffic.

I know that when I set the carbs up at 12 flats down and 3/4 - 1 turn on the screws it will not start. It is currently running at about 16 flats per carb and 1/4 to 1/2 turn on the screws.

Any suggestions before I start over this afternoon afterwork. (The carbs are clean, there are no leaksand the choke is free and does not stick)
 
Backfiring through the carbs is a sign of lean mixture... I think. When you get home check the color of the plugs and see if one carb is lean and the other is rich. I have a theory about your mismatched carbs.
 
OK, actually I have tool in the car, I can check around noon, when I will be going to another office across town, I will take the four of them out and note the color and get back on line early this afternoon. What are you thinking??
 
Hesitation under load can be many a diagnosis from a bad plug to loose wire etc. One cylinder isn't getting what it needs to perform and since the carbs have been adjusted, I think I might know where Trevor is going.
Check those wires etc too.
 
Barry that sure is a nice looking red midget, gota love those round archs. Think I could do without the orange plastic lights on the sides though. But hay.
 
i think jack wants in the RWA club /ubbthreads/images/graemlins/smile.gif......
since i set MY timing...i get good
power at speed but taking of is a little
ch ch chuggy.....i also get a bit of burpple
when i coast down big hills in gear....
sound like me and woodie are in the same
situation....thought id advance my timing
slightly as it took off fine till i retarded it
to where it should be......idk.......z
 
Zimmy that timeing is for a factory fresh engine, yours is going to be different. The factory specs are only a starting point now. If a bit advance cures the problem then that's what it wants. Remember factory fresh is not a rebuild it is all new, everything.
 
Re: once more into the breach ...er carbs.. solved

Well Trevor, Iwent out and took out the plugs, see attached picture. Right to left 1,2,3,4. All even light tan colour.
BUT, when taking them out I noticed that the number 1 wire was not "firm" on the top of the plug.
When reinstalling the plugs I made sure the wires all snapped onto the plugs.

Started and ran so much smoother on the way here, no backfire through the carb, no real bad burrble when letting of the gas in 4th or 3rd.

I believe that my 17 yr old must have hit the wire with the socket extension last week when he was rotating the dizzy and tightening loosening the nut, while I was under the car doing the timing.

SO, another problem turns out to be nothing but CO (current owner) learning. Ya know, this car makes me feel 18, and that I know nothing about cars. But it also makes me feel 18 when I DRIVE IT LIKE I STOLE IT, YEAH BABYYYYYY!!!!!!!
 

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Re: once more into the breach ...er carbs.. solved

Ha, cheep fix. Bet it does not happen to you again.
 
Re: once more into the breach ...er carbs.. solved

Lets wait and see if the problem is totally gone. It sounds like there is more than one issue causing what you described.
 
Re: once more into the breach ...er carbs.. solved

It happened to me just after I messed with the carbs and turned out to be the connector inside the wire wasn't gripping the plug snuggly, was running like a dog.
New wires = run like a tiger.
Glad it's sorted but as Trevor said, keep your ear on it just in case something more sinister and less obvious is lurking beneath.
 
Re: once more into the breach ...er carbs.. solved

Ok, I will recheck the plugs , I drive about 10 miles each way to and from work. Done 10 now. When should I pull them, and I will know if it gone, tomorrow morning when I start/drive from cold
 
Re: once more into the breach ...er carbs.. solved

Well this morning was cool and rainy, went out and pulled the choke 1/2 way out, (for the last week I've been pulling all the way out) turned the key and vroom, started right up, let it run for about 30 seconds pushed the choke in to where the fast idle was just on (1500RPM) and drove away. After about 2 minutes of driving pushed the choke all the way in. NO hesitations any time, no backfire through the carb, no excess burrble when letting off the gas. The problem did not rear its head today. I will run the car until the weekend then recheck the plugs. The car seems to be running fine. Now to let sleeping dogs lie or running cars be. Unfortunately I love to scratch a dog.......
 
Re: once more into the breach ...er carbs.. solved

congratulations!
mines running ok...but
i got the feeling even if it
was running great id still
try to make it better /ubbthreads/images/graemlins/wink.gif
gotta be a sickness..haha ...
whats ur timing set at? any idea?..z
 
Re: once more into the breach ...er carbs.. solved

Zimmy my timing is set to 10degrees (maybe 11) BTDC set dynamically last week. It feels a little like a dog on a leash, I may retard to 15 degrees. I will see, cause it is running fine. Before I set the timing I was running at 20 -25 BTDC and it was very free, but idle and such was way off(it waivered from 1200 to 700rpm). Now idle is rock solid at 1000. I don't know, its a sleeping dog right now,,gonna have to scratch it sooner or later)
 
Re: once more into the breach ...er carbs.. solved

Back it off just a degree or so at a time till you like it.
 
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