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Rb20 Cooling System

gillies2001

By gillies2001,
in Engines & Forced Induction

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gillies2001 Collaborator

gillies2001

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To stop less risk of hose failure, has any body used less cooling system hoses on the RB20DET, ( only for a warm climate)

I am thinking of removing the hoses on the inlet manifold, throttle butterfly and the cooling system bleed hoses.

( the cooling system bleeding could be done by jacking the front of the car and bleeding by the radiator cap, which would be the highest point )

The hoses to stay (not removed) are the heater hoses, turbo return hose and radiator hoses

Are there any other hoses that could be removed?

Any ideas

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gillies2001 Collaborator

gillies2001

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I should have explained as i am doing an engine rebuild, and as all the hoses are over 20 years old and 200,000K, they should be replaced, i thought maybe, just replace the least amount to do the job.

blind_elk Grand Master

blind_elk

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Also, would not heating the inlet manifold and the throttle body be an advantage, keeping the inlet air cooler ?

If it was an advantage, then Nissan would not have designed the engine to work with them.

The primary reason the hoses fail is if the engine has not been correctly treated with engine coolant.

GTSBoy Grand Master

GTSBoy

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If it was an advantage, then Nissan would not have designed the engine to work with them.

The primary reason the hoses fail is if the engine has not been correctly treated with engine coolant.

Now, both of those statements are just silly. Nissan heated the TB to stop icing problems when using the engines in a cold climate. There are very few places in Australia where you need to retain it. The very first thing I do to any RB is bypass the hose around the TB.

And the failure of coolant hoses (especially the ones under the inlet manifold) is just from age and heat. Doesn't matter if you've been using coolant made from de-ionised angel urine and the squeezings of virgin glycols, the hoses will still shit themselves eventually.

To the OP. Unless you know the function of all those little coolant hoses, especially the ones under the inlet manifold, don't bypass them, just replace them with new ones. There's a lot of moving of coolant from one part of the engine to the other that is done by those hoses, and some of it is quite necessary. New ones will last >15 years.

gillies2001 Collaborator

gillies2001

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Now, both of those statements are just silly. Nissan heated the TB to stop icing problems when using the engines in a cold climate. There are very few places in Australia where you need to retain it. The very first thing I do to any RB is bypass the hose around the TB.

And the failure of coolant hoses (especially the ones under the inlet manifold) is just from age and heat. Doesn't matter if you've been using coolant made from de-ionised angel urine and the squeezings of virgin glycols, the hoses will still shit themselves eventually.

To the OP. Unless you know the function of all those little coolant hoses, especially the ones under the inlet manifold, don't bypass them, just replace them with new ones. There's a lot of moving of coolant from one part of the engine to the other that is done by those hoses, and some of it is quite necessary. New ones will last >15 years.

gotRICE? Veteran

gotRICE?

Posted
Posted

. Nissan heated the TB to stop icing problems when using the engines in a cold climate. There are very few places in Australia where you need to retain it. The very first thing I do to any RB is bypass the hose around the TB.

I also believe it helps keep the IAT at a relatively consistent temperature for the stock ECU. The ECU is assuming the air is around X temp and will fuel and time for it. (seeing as RB25's dont have stock IAT if you dont include the AFM)

From what i have seen anyway.

gillies2001 Collaborator

gillies2001

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Thanks GTSBOY

It always did seem like a maze under the inlet manifolds on the RB20DET and RB26DETT until i had the engines out.

It now looks a lot more simple and logical to workout which hoses are required to make it all work.

And as you said some of those hoses are only needed in very cold climates to stop icing up

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