5 hours ago, jalexquijano said:

Mechanic says the carbs could suck fresh air at idle instead of the hot air trapped under the hood during idle and it could help avoiding the plugs getting sooty

Is this the same mechanic that messed with your carbs and didn't really have a clue about what he was doing?  Did he explain how that "fresh" air would find its way to #4 cylinder to cure the soot problem and why the trapped hot air doesn't foul the other five plugs?  I suggest finding another mechanic. 

Dennis

 

 

Edited June 15, 20186 yr by psdenno

Lets get a photo of your compression tester too. Do you have a good o-ring on it?

Just arrived in the mail???

On 6/12/2018 at 10:14 AM, 240260280 said:

"Made in Japan" for Z guys means 100% perfect fit and function.

Yup. OEM Nissan Only!  No Bosch for me.

Well last night i pulled the choke 3/4 and crank the engine. Left the choke on for a minute, drove the car slowly until it warmed up and after that started accelerating but started noticing some hesitation. Got home and pulled plug number 4 which came out dark and i suspect it is clearly the cause of the hesitation. Now that i got a new cap and rotor should i clean the distributor with contact cleaner or should i just simply replace the old rotor and cap with the new bosch set? Im also replacing that plug as i guess it is already damaged.

 @jalexquijano Did you look at any of the other plugs? It would be a good idea just to confirm the rest look OK. If they look good I'd just replace the cap, rotor and # 4 plug. I don't think I'd spray anything just yet. If five of the six plugs look good the problem is narrowed down to the cap, rotor or plug wire, assuming the compression is still good. Do you have access to an ohm meter?

Pulling choke will do that.

38 minutes ago, 240260280 said:

Pulling choke will do that.

Good. How long shoud i pull the choke when cranking the engine? 20 secs?

Yes i do have an ohm meter at home. What do you want me to measure?

or choke, only use it to start the car when it is cold. Once it is running, turn it off.

Note that sometimes the choke cable is in the off position in the cockpit  but the jet on the bottom of the carb is stuck down. This will cause too much fuel to be added.

You may have to reach under the carb and push up on the jet to make sure it is not stuck down.

Here is a video of the jet moving. It sticks at  00:13 in the video.

 

Edited June 28, 20186 yr by 240260280

In the "Just SUs" DVD Steve, I think?, bends that arm that connects the nozzle to the linkage to free up the nozzle.  I had to do that to that red 240 I had.  Somehow it had gotten bent and was causing a bind.  Just an FYI Jalex, hopefully you won't have to do that. ?

10 minutes ago, siteunseen said:

In the "Just SUs" DVD Steve, I think?, bends that arm that connects the nozzle to the linkage to free up the nozzle.  I had to do that to that red 240 I had.  Somehow it had gotten bent and was causing a bind.  Just an FYI Jalex, hopefully you won't have to do that. ?

Also, when the hose is connected, it balances the "push" of the rod so there is less sticking of the jet due to torque imbalance. The jet in the video worked fine when the hose was attached.