[gboone]

I'm helping a friend get his '73 240Z running better. I drove it yesterday and it seems really low on power. After some quick glancing, I noticed there are 2 fittings on the intake manifold that have no hoses connected to them. These are about 1/2" diameter steel fittings. One is at the front of the manifold and has a 45 degree bend. The other is at the rear of the manifold and has a 90 degree bend.

It seems that since these are open fittings that they are allowing excess air into the intake and would make the air fuel ratio extremely lean. What are they supposed to be connected to?

Anyone got a digital pic of their 240Z engine that you could email me, since I don't have any references to go by to figure out a bunch of other missing hoses on various fittings.

TIA,
Gary

 

[WillieBoy240Z]

I could be wrong, but it sounds like you are describing the carb preheating feature on those cars. A hose delivered water from the radiator to warm up the carberators a little faster.

If this is the case, don't worry about it and start looking somewhere else for your power problems.

 

[Sean73]

Willie is right, the pipes are for coolant, and many people disconnect them as they are unneccessary in warm climates.

 

[gboone]

Thanks WillieBoy & Sean,
Your answers make sense. But it might be handy to have them hooked in Wyoming. Where do the hoses connect?
Gary

 

[luggnut73]

The front one connects to the fitting at the thermostat and the one at the rear goes around the rear of the head and connects with the heater discharge and cintinues to the fitting at the water pump. Good luck Gary Portland Or.