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-   -   New odd starting issue (https://www.rx7club.com/1st-generation-specific-1979-1985-18/new-odd-starting-issue-1127839/)

Ckforker 07-02-18 09:57 AM

New odd starting issue
 
If the car sits for more than a day, it will crank for several minutes before firing. Once running, it's flawless. Leads me to believe it's fuel related, but I think that would persist while running. The float level stays about 1/3-1/2, so it should be getting fuel at start up.

Have not dumped fuel in the carb, but will test that at some point. I would hate to flood it.

Hopefully this weekend I can start testing spark, but again it would seem to affect running.
Thanks

Jeff20B 07-02-18 10:03 AM

Have you tried pumping the pedal a couple times to get some accel pump shot into the engine?

Ckforker 07-02-18 12:30 PM

Yes, pumping doesn't change it, which is also odd as even if it would cough, I'd have something to go on. I can hear the fuel pump with ignition on and have let it sit in the on position for a minute or 2 before cranking and nothing.

t_g_farrell 07-02-18 07:11 PM

How old is the battery? A weak battery can be like this. Also check the float level before turning the key on. It could be the carb is siphoning itself after sitting. When it does start how much smoke blows out and what color is it?

BTW, see you at C&C saturday?

Ckforker 07-02-18 07:25 PM

Checked floats before and always has fuel. Battery tests good, stays on trickle charge. Today was the first time it did it after driving, fully warmed up and shut it off for 30 minutes while at the store. Finally started. Runs excellent once running, so very puzzling.
Yes I'll be at C&C. Wanna meet at the Belk parking lot?

Ckforker 07-02-18 08:27 PM

Forgot to mention, just small amount of bluish smoke that it always makes after sitting for a few days, not black like I'd think if too much fuel. Gonna check everything I can tomorrow morning before it gets hot and I get too irritated 😡

7aull 07-03-18 02:46 AM

How old are the battery cables??? These can lead to al lsorts of electrical grief as they age out. Even if they look fine externally, moisture leaching up from ends can corrode insides, making juice flow problematic. And rotor motors need a LOT of good clean DC to ignite. If you have no record of a change out, presume they are originals and replace them.

Another hard start possibility: how old are the PLUGS. fresh set could do wonders...

Stu Aull
80GS
AZ

t_g_farrell 07-03-18 09:06 AM


Originally Posted by Ckforker (Post 12285614)
Checked floats before and always has fuel. Battery tests good, stays on trickle charge. Today was the first time it did it after driving, fully warmed up and shut it off for 30 minutes while at the store. Finally started. Runs excellent once running, so very puzzling.
Yes I'll be at C&C. Wanna meet at the Belk parking lot?

Yup, I will send txt to you and Jim later this week.

Ckforker 07-03-18 02:39 PM

Thanks Stu, all the wiring battery alternator, starter etc are newish, 3 years old, starter cranks fast and strong. Gonna test the ignitors, since it has a new old stock dizzy cap an new wires and plugs have about 600 miles. I'm just hoping I didn't mess something up when I changed the water pump and thermostat.

Ckforker 07-03-18 04:47 PM

After sitting all day, it does have a little leak down. Gonna let it sit another day and see if more leaks from the bowl. Hopefully it lasts through the summer, this winter I'll do a complete tear down of the carb. Starting to get too many little quirks that aren't getting any better. Not something I'm looking forward to.

grantrx713b 07-04-18 04:45 PM

/Has the carb been rebuilt recently?

Ckforker 07-04-18 08:21 PM

Carb has never been touched, the car only has 67k, but fear it's time for a rebuild.

Jeff20B 07-05-18 12:58 AM

Do you know the rules to follow when you rebuild these carbs?

Ckforker 07-05-18 06:44 AM

The last few days I've been doing a lot of research, don't mess with floats, reuse needles and seats, video disassemble process on a big white sheet. I'm not gonna mess with hogging out, I just want it original.

Jeff20B 07-05-18 10:20 AM

Good man! And just realize that the boosters do not need to be removed, but if you decide to wash and degrease the carb, you should take out all the air bleeds across the top of the main body so they don't get water in them, and use compressed air to blow all the passages out until they are dry. The baseplate can be grimy but two degreasings will work. Oh and the paper-thin gasket that comes in the kit is junk. I use them as a template on thicker paper and only punch the holes I will be using. But if in doubt, you could punch them all out. This is the gasket between the main body and baseplate. I do not use any of the gaskets for the phenolic spacer as the originals are permanently bonded and should be left alone. The top gasket or air horn gasket can be used but some of the holes are a bit off, so I like to oval the bad ones a bit until the screws can fit through well without binding.


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