Jump to content
HybridZ

Need help with cooling!


Recommended Posts

Today I was driving my 78 280z, it was around 91 degrees outside and I stopped somewhere shut my car off and came back a few minutes later and it wouldn't start, the temp meter was almost 3/4's of the gauge. What can I do to prevent this from happening again? Any help is appreciated

Link to comment
Share on other sites

what is your setup? Stock, modified etc....

 

When I got my z 260 last October pretty much stock with 2 2brl weber's it ran great on short trips. My first road trip pegged the temp gauge. Ended up being the radiator. 39 years of wear and tear finally plugged it up to much. I bought a 3 row aluminum radiator and new water pump. Since I have had issues of getting heat in the motor.

 

Of course 95 temp days it stays around 180 to 190 water temps or  gauge reading right in the middle.

Link to comment
Share on other sites

It is stock, I checked the coolant level after getting it home and letting it cool down completely. It was at a normal level. I replaced the thermostat about 2 months ago. So is it possible my radiator is plugged up?

Link to comment
Share on other sites

There's a problem with the L6 and EFI commonly called the "hot start" problem.  Nissan installed a cooling fan for the fuel rail and injectors on the S130's to try and avoid it.  Search "hot start" or "vapor lock" to get some ideas.

 

Did the engine not start at all or did it start but run so bad that you shut it off and waited?

Edited by NewZed
Link to comment
Share on other sites

If you've removed any heat shields around the engine you should put them back.  Also, winter blend gasoline seems to make the problem worse, for me anyway.  So if you're still on a tank of winter gas, go get a fill of new gasoline.  My engine had terrible hot start issues in the winter.

Edited by NewZed
Link to comment
Share on other sites

In the meantime you could pull out your stock radiator, Flush it out with water from both ends and see if you can't clean it out.  You may even just take it to a radiator shop and have them boil it.  It should be a lot cheaper than buying the Alum rad. Inspect your hoses while it's out, you could have a blocked of collapsing hose messing with your flow.  I had my upper hose shred internally and pop on christmas day some 10 years ago during a "white christmas" storm on my way to my old GF's house. Needless to say I was about 3 hours late.  Thanks to a hose :(   it's awesome to see massive steam pour out of the 280Z hood vents though.

Link to comment
Share on other sites

I've had the hot start issue and noticed that my gauge was always up at the three quarter mark after sitting.  But my radiator was fine.  It's just heat soak in to the thermostat housing once the coolant stops flowing.  There is also heat flow in to the injectors and rail from the block and manifolds.

 

Changing your radiator based on what happens when the engine isn't running wouldn't make sense.  The radiator isn't really in use unless coolant is flowing.

Link to comment
Share on other sites

You don't. This is covered over and over...

The ZX's used a three second fuel pump prime to refill the rail and combat hot restart issues.

 

Run a 160 thermostat in the summer to keep the blast furnace of the radiator only blowing 170-180 F air over your engine, and prime the fuel rail on restart before cranking and watch your summer heat soak problems go away entirely.

 

If I can drive across the desert southwest towing an 800# trailer without hot restart problems in Mid June in 120F+ ambient s, 91 should be child's play!

Link to comment
Share on other sites

Without the fuel prime, you don't address what causes the no-start. The prime keeps it running no matter which thermostat you have in there. This is a fuel issue, not an overheating issue.

 

I just told you how to minimise it, unless you prime before hot restart, you will have this issue!

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...