S14 rb20det conversion. Cooling/fan issues

[DRFT 14]

What did you guys do about cooling fans with your rb conversions into your silvias? Ive got the original S14 fan and im thinking of buying another fan from the wreckers and *somehow* installing them on the other side of the radiator facing towards the engine bay. Will probably tow the car (overheats after 3 minutes) to the electirician to wire it up. Am I on the right track here? Can someone please post in detail what they did and whether it rectifyed the overheating problem or not? Im still wondering how im going to fit the fans with my 2 1/2inch intercooler piping going across the top of the radiator and what im going to use to attach them securely

Please let me know what you guys did in your setups. thanx

[USMCgetsome]

well let me just say you should have searched before you posted. You probably pissed off all the damn RB GURU'S.

Anyhow, are you using the stock ka/rb radiator or koyo? And are you trying to use pushers or pullers? i'm running a 1 14" pusher fan infront of the radiator. Some people have used puller fans that go in between the radiator and engine and that seems to be the best route. your gonna need a fan/fans that push over 2000cfm.

There's also another way to fit puller fans on the koyo radiator it's called notching and it's already been explained soo do a search.

[DRFT 14]

Well, i did the search and read through some posts but found nothing on the physical procedure of actually installing the fans. There is absolutely no room for a fan in between the radiator and engine. So im going to need a couple of fans pushing through the radiator on the other side which is what you said you have setup on your car. Can you let me know exactly what you did to fit them on. Im thinking cable tie the damn things on.....

[NISMO_RB25]

most of the aftermarket fans come with plastic rods that you push through the radiator and the fans, then you put a nut on the end of the plastic rod and those hold your fans on. They sell them at autozone if you don't have some.

[USMCgetsome]

yes sir. that is very correct. Look them up on jegs to get a visual should be fan installation kit. The radiator is nothing but 2 screws. once removed(screws) the radiator is easy to lean forward or backward or just uninstall. You never said what radiator you using. I'll take some pics of the radiator and fan that way you'll have a visual. Keep in mind that everyone agrees that PULLER fans are the best route but if you get a PERMA COOL/FAL reversible fan that pushes or pulls more than 2000cfm you should be fine. Check on ebay for PERMA COOL fans i plan on running one very soon the specs are 2900cfm reversible fan and some come with the mounting kit or you can just purchase one for about $10. pics will be posted this afternoon.

[yellow_jacket]

It overheats after 3 minutes of normal driving or after 3 minutes of sitting at idle at cold start up? Either way it shouldn't be the fans.

[Wulfgang]

I have an S14 with RB20.

Just to give you some idea... we just had a warm snap here in Illinois (up in the 40's). I took the fan relay out of my car (turned the fan off) and went out for some launch practice and to get some 0-60 times. After about 25 minutes of thrashing it, the engine was still cool... hadn't even warmed up to normal yet.

And last summer, with just 1 Perma-Cool 12", it took over 15 minutes to reach normal temps while driving. Obviously that is too much cooling.

This is with stock KA radiator and no condenser (yet).

Yellowjacket is right. You've got bigger problems. Did you replace the waterpump/thermostat yet?

[BoostFab]

i'm running two generic slim 12" pushers and rb20det radiator....no over heating issue....

like the guys said, there's some other issue. make sure you bleed the air out of your coolant system.

[rbsileighty]

I have an S14 with RB20.

Just to give you some idea... we just had a warm snap here in Illinois (up in the 40's). I took the fan relay out of my car (turned the fan off) and went out for some launch practice and to get some 0-60 times. After about 25 minutes of thrashing it, the engine was still cool... hadn't even warmed up to normal yet.

And last summer, with just 1 Perma-Cool 12", it took over 15 minutes to reach normal temps while driving. Obviously that is too much cooling.

This is with stock KA radiator and no condenser (yet).

Yellowjacket is right. You've got bigger problems. Did you replace the waterpump/thermostat yet?

I am running two of those Wulf... and mine operates at the normal temp level on the stock gauge. Before I replaced the old KA sending unit with a new one (~$20 at the Nissan dealer) it use to look like it would take forever to warm up. Once it did warm up with the old sending unit, it would read really cool... not anymore... now it's usually always normal. This is in 70+ degree weather back in the summer. Unless I'm heading down the highway I usually have to keep the fans on in warm weather... haven't had to many chances to drive it this winter.

These fans do the trick, and I would definitely recommend them. My buddy's car is running 2 10" fans from autozone and his is doing fine in the same kind of weather... we tend to run the fans all of the time, but his has been ok at points in cold weather (this is Hybridone's S14.5 who has sold his to another friend of ours... we got it running back in 03). Both of our cars have Hybrid FMIC's and still do well temp wise in the summer with the fans running.

Look at the link in my signature to see how my fans are mounted... be sure to run a 30 amp relay when you hook them up. Good luck bud...

[mmatl16]

when i got mine out of the shop it was overheating all the time with normal driving. i had a pusher between the radiator and the motor.

i then took off the a/c condensor and switched the fan around to the front so it wasnt going against air flow. it hasnt overheated since.......but no a/c

[lyon23]

Well, i did the search and read through some posts but found nothing on the physical procedure of actually installing the fans. There is absolutely no room for a fan in between the radiator and engine. So im going to need a couple of fans pushing through the radiator on the other side which is what you said you have setup on your car. Can you let me know exactly what you did to fit them on. Im thinking cable tie the damn things on.....

I have one in front of mine between the two and the other in front of the condensor for the a/c. yes I have working a/c and it doesn't overheat...I believe the permacools are the best.. I have 2 10" one pushing one pulling, and like wulfgang said if you really want it cold put the 12" in there...I also think you sould try and bleed your system if you thermostat and water pump are good.

[DRFT 14]

Thanks for the replys guys. I just upgraded my radiator today from a beatup single core radiator (used temporarily just to get the motor running) to a mint condition rb20det twin core radiator. The result is that the engine runs cooler for a little longer. It now takes about 5 minutes of thrashing before it overheats. But by the sounds of your posts, this is still too little time and their may be other problems other than the fans. Id like to remove my thermostat, but the positioning of the bolts make it almost impossible to reach them. And I dont know how to replace the waterpump either. How much is it for a new water pump? Is there a way to check wether or not the waterpump is functioning properly?

Also, if i understood your posts correctly, the electric fans simply "push into" the fins on the radiator? This sounds very simple to install. But wouldnt this damage the fins at all? I was planning on just buying some normal fans from the wreckers. They only cost around $20 (New zealand) each, and ive already got the old one from my SR20DE. This makes for a much cheaper setup, cause brand new electric fans go for $100 over here for one. What do you guys think I should do. Some how try to attach two normal fans to the radiator (in a push configeration blowing towards the motor from the other side of the radiator) and taking it to an electrician to wire up. Or go for the more expensive brand new 12inch electric fans?

Thanx alot guys much appreciated.

[DRFT 14]

Pics of my car here by the way- http://www.skylinesaustralia.c...13465

Also, how to I go about bleeding the coolant system?

[Darius]

Is there a possibility of the thermostat being stuck shut so no water flows through the motor and just heats up in place??

[USMCgetsome]

since i've been reading i know that it is a pain in the *** to remove the t-stat. But it can be done and draining your coolant, there should be a plug on the bottom end of the radiator to release the coolant. I'm sure that there is a coolant issue with your rb. Take the belt off the water pump and spin the pulley to the pump. It if spins freely without any lag or resistance you got probs. No real way to check the t-stat except for taking it out and put it in 180degree water to see if it physically opens or closes. Just change them. If your in NZ, it shouldn't be hard to get an N1 WATER PUMP OR STOCK or even the thermostat.

[Wulfgang]

180ºF water is easier and cheaper to get than a new thermostat.

[Eikon]

Sounds to me like it's your water pump.

I had the same problem... i swapped out and put in a new radiator, thermostat, flushed the system, checked for head gasket problems, etc... Nothing helped.

Finally did the water pump/timing belt... Turns out the water pump was completely shot... all the fins corroded away completely.. It was not moving any water at all.

I would suggest running through a series of tests... 1.) flush coolant system2.) test thermostat3.) test for bad head gasket

If all these lead to nothing...it's your water pump. A very common problem with RB swaps.

If you do a search on water pumps, you should find my thread with pics of the bad pump. Check out skylinesownunder.com and look through the technical section... I have a thread there about my whole process of figuring it out.

Good luck!