Jump to content
SAU Community

Recommended Posts

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

Link to comment
https://www.sau.com.au/forums/topic/373373-rb20-cooling-system/
Share on other sites

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.

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.

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.

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.

. 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.

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • My guesstimate, with no real numbers to back it up, is it won't effect it greatly at all.its not a huge change in position, and I can't see the air flow changing from in turbulence that much based on distance, and what's in front of it. Johnny and Brad may have some more numbers to share from experience though.
    • Which solenoid? Why was it changed? Again, why was this done? ...well, these wear..but ultimately, why was it changed? Did you reset the idle voltage level after fitment? I'm just a tad confused ~ the flash code doesn't allude to these items being faulty, so in my mind the only reason to change these things, would be some drive-ability issue....and if that's the case, what was the problem? Those questions aside, check if the dropping resistor is OK ...should be 11~14 ohms (TCU doesn't throw a flash code for this) ~ also, these TCU designs have full time power (to keep fault code RAM alive), and I think that'll throw a logic code (as opposed to the 10 hardware codes), if that power is missing (or the ram has gone bad in the TCU, which you can check..but that's another story here perhaps).
    • Question for people who "know stuff" I am looking at doing the new intake like the one in the picture (the pictured is designed for the OEM TB and intake plenum), this design has the filter behind the front bar, but, the filter sits where the OEM duct heads into the front bar, and the standard aperture when the OEM ducting is removed allows the filter to pulled back out of the front bar into the engine bay for servicing, a simple blanking plate is used to seal the aperture behind the filter This will require a 45° silicone hose from the TB, like the alloy pipe that is currently there, to another 45° silicone hose to get a straight run to the aperture in the front bar Question: how will it effect the tune if I move the MAF about 100-150mm forward, the red is around where my MAF is currently, and the green would be where it would end up Like this This is the hole the filter goes through  Ends up like this LOL..Cheers    
    • Despite the level up question, actually I do know what that is....it is a pressure sender wire.  So check out around the oil filter for an oil pressure sender, or maybe fuel pressure near the filter or on the engine. Possibly but less likely coolant pressure sensor because they tend to be combined temp/pressure senders if you have one. Could also be brake pressure (in a brake line somewhere pre ABS) but maybe I'm the only one that has that on a skyline.
    • Pull codes via the self-diagnosis procedure. As far as I can tell this is just a sign of transmission issues but not a code unto itself.
×
×
  • Create New...