esmith972

It's me again with another newbie question.

I quickly found out that my fan clutch is bad, but at the same time I found out when I get to about 4k RPMs, it seems a little sluggish. I want to do an electric fan conversion with a variable resistor so it doesn't just turn on and off but that's last on the "honey-do" list. (I now pronounce you man and 7. )

On another semi-related note, what would cause bucking when I floor the car while already rolling? It only does it when I punch it instead of rolling into the accelerator. I say bucking, what I mean is it's almost like it loses spark for a split second then kicks in and takes off. It only does it occasionally and I heard it was just because it's carbureated. Of course, it's a Nikki carb. To my knowledge, the carb is in decent condition with the secondaries hooked up.

Speaking of secondaries, how do I test if they are opening?

Thanks again for such an awesome community; I feel at home here now.

esmith972

Update.

I was out troubleshooting the problem and found that the bigger cylinders on the carb won't open. I just had a friend punch the accelerator, hold it at 5k RPMs, etc. They won't open. Any ideas?

yetterben

They wont open at idle unless you manualy move the linkage

gsl-se addict

iTrader: (3)

also, check here: https://www.rx7club.com/1st-generation-specific-1979-1985-18/common-cause-power-loss-nikki-carbureted-models-632007/

bliffle

Sounds like the infamous 'teeter totter' problem.

Kentetsu

Yeah, run a search for "teeter totter"...

gsl-se addict

iTrader: (3)

my link was for the teeter totter prob...

esmith972

Man this community friggin rocks. Thanks *again*. We all owe each other beers.

esmith972

The teeter totter thing is where the rod hooks up to the spring thing on the firewall side of the carb; right? If so, that's not the problem it's hooked up.

While fooling around, I noticed the secondaries don't open up all the way. The lever below the diaphragm (when pushed of course) will only open them up maybe 45 degrees or less UNLESS I force the **** out of it to open. What the heck would cause this?

It gets to about 4k on a normal throttle when it seems to lose all "pull," so I either give it a little more gas, or I shift. If I keep the throttle where it is, it won't pick up anymore speed.

gsl-se addict

iTrader: (3)

It should look like this:

esmith972

Ok, that's how it is.

Now the question is, what about the secondaries?

gsl-se addict

iTrader: (3)

the secondaries are only opened under load (vacuum operated). You cannot check their function by just revving in neutral. You could look into converting to mechanical secondaries (they then open at a fixed throttle position).

- check your fuel filter (replace it, they are only like $3-$4)
- also, you could have a clogged catalytic converter
- make sure accelerator pump is working (car off, press the throttle, should see a squirt of fuel into primary barrels). If this isn't working, you will get a delay/bog when hitting the throttle
- check timing to make sure that it is set properly

bliffle

Why do you think your fan clutch is bad?

Kentetsu

Could be clogged jets. Was the car sitting for an extended period of time?

1985RX-7

I know the if the cluch on the fan is good than it should only freespin I think its 1 1/2 turns after shut off the motor. But i did the eletric fan swap and like it way better for the the reason of it looks better you don't hit your fingers while your leaning over it while its running lol and the that little bit a power.

esmith972

bliffle, when I first start it in the morning, with choke on, the fan WILL not slow down. It howls no matter if it's hot, cold, in between, whatever.

Kentetsu, no idea. If it was, how could I check or fix it? The primaries get fuel down no problem but the secondaries fuel supply seems... slow?

1985RX-7, I've actually got a V6 mustang electric fan sitting in the trunk right now. I want to do the electric conversion but I want to do it right (variable resistor instead of turning on and off).

esmith972

Update: Call me a liar, but I replaced my altenator/fan belt and all of my car's problems have disappeared. The fan howl? Gone. The bucking? Gone.

Moral of the story: MAINTAIN YOUR FRIGGIN CAR! :P

There is a new concern though. The 4k RPM squeal was being caused by the air pump. Is it absolutely necessary to have that hooked up? The line is hooked up to the catalytic converter and now she backfires like crazy.