Electric fan or new fan clutch/shroud for my 240z?

[jalexquijano]

Focus on a way to remove that heat from the carburetors. 

[siteunseen]

I'd think an electric pump continually running fuel through but you need to sure it's an open flowing system. The return to the tank should be open allowing fuel to flow non stop. Fuel is cooling when it flows freely.

You say manifold heat? Have you thought of replacing that cast iron heat holding exhaust manifold with a low heat ceramic header? You'd need to research this but maybe get the OE manifold coated with ceramic. On second thought a MSA ceramic header would be easy and similar cost as removing the OE and having it coared. I've got them on mine and they do a fantastic job dissipating heat. My carbs are cool when I touch them.

The reason I'm on California Datsun is simple. He does half arse work and charges top dollar. Your coolant passages could be clogged up with years of calcium deposits. I've rebuilt 2 motors and those were all clogged up. The casting plugs come out before the block gets vatted, if it did get vatted before the rebuild.

 

[dutchzcarguy]

15 hours ago, jalexquijano said:

champion 3 row radiator. Still struggling with percolation during stop and go traffic in Panama.

Yeah thats a aluminium radiator.. i always drive over them and throw them as far away as i can!  What you need is a radiator with a copper core.

What is that with you guys and aluminum (Yeah, i left out the i... 😉 ) radiators?  they suck! Yes i know copper is expensive but it cools way better!  

take a 10" strip of aluminium and one of copper. (same thickness and width) hold them in your hand, i take the aluminium one.. and we hold a lighter under the end of it and look who can hold on to the piece of metal the longest! haha.. (more safe to do this in a vice and measure with a infrared thermometer 😉 ) 

[foosman]

On 1/6/2022 at 7:29 AM, dutchzcarguy said:

Yeah thats a aluminium radiator.. i always drive over them and throw them as far away as i can!  What you need is a radiator with a copper core.

What is that with you guys and aluminum (Yeah, i left out the i... 😉 ) radiators?  they suck! Yes i know copper is expensive but it cools way better!  

take a 10" strip of aluminium and one of copper. (same thickness and width) hold them in your hand, i take the aluminium one.. and we hold a lighter under the end of it and look who can hold on to the piece of metal the longest! haha.. (more safe to do this in a vice and measure with a infrared thermometer 😉 ) 

Sure - copper conducts heat more efficiently than aluminum, but radiator efficiency involves more than just the metal used.  Tube diameter, surface area, airflow restriction - in some designs, aluminum allows you to optimize these parameters better than copper does.  To imply that all aluminum radiators are crap is a bit short-sighted - I've used an OE-style aluminum radiator in my Corvette for years, and it cools just fine.

[jalexquijano]

So at the end what is the remedy? Just spend 400 usd in MSA fans and shroud and a new alternator? 

[dutchzcarguy]

1 hour ago, foosman said:

I've used an OE-style aluminum radiator in my Corvette for years, and it cools just fine.

Yes, but in the corvette there is room for a big radiator and it was made for it.. this is not the case with the old datsuns..

Okay i was a bit harsh on the alu radiator, but i get a bit angry of the fact that they are praised to be such good (Chinese made) rad's and they are junk..  a good radiator for €169 is junk.. I use a copper original in my 240z and it's in there for decades..

[jalexquijano]

Ok as i said before my car has a champion 3 row radiator with 16lbs rad cap and original 1972 datsun plastic fan cluch with msa shroud. It also has the phenolic spacers between the SU rounded 3 screws and additional heat shield. How come some users here have tackled this heat problem without spending more than 500usd in electric fans, shroud , thermoswitch and alternator?

[dutchzcarguy]

2 minutes ago, jalexquijano said:

16lbs rad cap

?? what is that.. you mean 1.6 ??  that  is 1.6/2 minus 10 percent is .72 kg is 720mbar pressure?? i don't know what you mean with 16Lbs..  1.6 pounds over pressure is much to low.. (mine has 1 or 1,2 kg = 1000 or 1200 mbar = 2,64 Lbs!  

(16 Lbs would be MUCH to high, your radiator can not hold 7,2 bar (ato)..  whatever... it will explode.. ) 

Also does the clutch from the fan work correct? if you give it a good pull it has to stop in quarter or less turn.. when hot/warm.. when cold it's about half a turn..

[Patcon]

Gasoline can vary greatly over the United states. I suspect even more so internationally.

You have tried a great many things but not always in a methodical manner. I too am unconvinced you don't have an internal issue

[Mark Maras]

 If the fan clutch appears to be working properly, I think ceramic coated headers may help. Cliff reports the carbs staying cool to the touch using ceramic headers. If it were mine, I'd also pull a freeze plug or two to check the coolant passages for corrosion and build up. No one knows knows if Cal. Datsun ever cleaned the coolant passages in the block? 

[jalexquijano]

27 minutes ago, dutchzcarguy said:

?? what is that.. you mean 1.6 ??  that  is 1.6/2 minus 10 percent is .72 kg is 720mbar pressure?? i don't know what you mean with 16Lbs..  1.6 pounds over pressure is much to low.. (mine has 1 or 1,2 kg = 1000 or 1200 mbar = 2,64 Lbs!  

(16 Lbs would be MUCH to high, your radiator can not hold 7,2 bar (ato)..  whatever... it will explode.. ) 

Also does the clutch from the fan work correct? if you give it a good pull it has to stop in quarter or less turn.. when hot/warm.. when cold it's about half a turn..

16 psi

[dutchzcarguy]

Hahaha... 😂  we in europe do not work with Lbs's or Psi's but even i know that are 2 different worlds, yes 16 Psi.. that's about right.. (little over 1 bar/ato.)  

Have you cleaned out the complete engine waterworks? maybe there is a lot of dirt/limestone in your coolingsystem.