Jump to content
HybridZ

z bogged out and cut


Recommended Posts

hey guys, i was wondering if you could help me possibly point out what happened to my 240z the other night as it would not start back up and i had to get it towed. heres some details on the car:

 

73 240z 4spd

running round top su carbs have not done final tune, running a little rich,

fairly new plugs, distributor, wires

petronix ignitor electronic ignition

 

current minor issues :

plugged in blower control, never tested out

slight coolant leak from heater control valve hose (only leaks and makes hissing sounds sometimes)

running rich, strong exhaust smell when at stoplight and shoots flames on upshifts

tach never worked, just goes straight to 8k rpm when ignition is switched on

speedometer recently stopped working

water temp sensor does not work

 

 

 

I have maybe driven the car a total of 10 times on short trips i would say 20 min tops and the car always ran fine (a little rich as it shoots flames every now and then. however, saturday night 60 degrees out i decided to test it out and drove it for over an hour straight (normal driving not racing) around town never went over 60 mph and the car ran fine. After about an hour of driving, i went to a store and parked it maybe 3 minutes. after i was done, car fired right up and off we went. 2 stop lights later the car starts bogging and showing a loss of 50% power as i was going up a very slight incline. The car then cuts power. I tried restarting it maybe 4 times and it fired up for a good 5 seconds before bogging and cutting again. it wouldnt start again after that so i had to have it towed home. I didnt have time to work on it that night, so i let it sit until today. Today, i checked to see if it has gas in the tank, looks around half tank, also checked to see if any hoses or electrical wires got disconnected and they all look fine. looked where the fuel filter is, and it looks like its flowing fine. Checked under the distributor and it looks okay. after trying to start it 4 times today, it cranked over and is running fine. I just drove it down the street and back today, and its running as if it never had a problem. any ideas would could have caused it to die on the the other night?

Link to comment
Share on other sites

What it sounds like to me is the power transistor is bad. When they start to go bad they will stop working once they get hot. Then when it cools down the car will fire up, but expect the same thing to happen again until it just completely goes out.

Link to comment
Share on other sites

That or maybe a Vapor lock. my old 260Z used to do that, it'd run fine, but if it got too warm it would sputter out and I wouldn't be able to go again unless I let it sit for 30 min. It's possible it could have been the same power transistor. Sold the car before figuring it out.

Link to comment
Share on other sites

<my bad...>

 

You might also check your Fusible links. I remember mine were pretty roasted and the car would sometimes suffer complete systems failure when water would get into them. (my caps were bad)

 

Phar

Edited by Pharaohabq
Link to comment
Share on other sites

That is NOT a power transistor! That is the ballast resistor. It's purpose is to protect the points in the distributor, which the OP does not seem to have since he says he has a Pertronix ignition.

 

xplosive - hard to diagnose your problem from afar, it could be several factors. Best to go back to basics - fuel, air, spark and verify what you have or don't have when the no-start condition exists.

 

Could be crud in the tank, could be "vapor lock" (search fuel percolation which is a more accurate term), could be an intermittent ignition problem. You will most likely have to re-create the problem and go from there.

Link to comment
Share on other sites

DCZ is right. Go back to basics: Fuel, Spark, Compression. Compression does not go away and come back so check on fuel and spark. The next time it stalls pull the wire off any plug wire and crank to see if you have spark. If yes you probably have a fuel problem. If no you have a spark problem.

 

I must admit it sounds just like a clogged fuel filter. Pull it completely off and blow though it. You should be able to almost breath through it. Any resistance at all you should change it. If it is not plugged climb under the rear of the car and make sure there isn't one back there.

 

For spark I think 73s still had points (before you replaced it with pertronix)so I don't think you have a power resistor. PRs were used with early electronic ignitions like that used in the 280Z and I think they were acctualy amplifiers (but this is beside the point) and they were often effected by heat like after running for awhile and then slowing down to let the engine compartment hot soak. Back to the point: It could be the Pertronix module in the distributor is failing when hot. Simply put points back in to see if your problem goes away. If it does get a new pertronix unit.

 

good luck

 

Paul

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...