Hawkflyer

Hi-

My new 1997 S/C 4Runner has brown sludge for coolant and a wet rusty block for a radiator cap.


There used to be a REAL NASTY flush that you could by at Carquest to help with neglected systems like this. I bought a flush and ran it through the best I could, but this thing is nasty. After 4-5 flushes and a fresh fill, this coolant is STILL nasty.

I am thinking of installing a "Flush and Fill T" to simplify this process. Do these radiators not have a drain petcock? What are you guys using for a real good flush that I can buy in TX?

FogRunner

What you want is Prestone Heavy Duty Cooling System Cleaner, GM P/N 12346500.

It's a two part system, the active cleaner comes in powder and you put it in the cooling system and run for a while. Then drain it will it with water and put it the neutralizer and run for a while, then drain and fill with coolant and distilled water and call it a day.

Its pretty hard core stuff and will clean the NASTIEST of cooling systems problems.

Hawkflyer

NICE...... thats what I needed!



Kyle

Hawkflyer

CLR? No ? Hmmmm Ill try that out!



Kyle

brian2sun

Not to worry you, but if your coolant is rusty sludge, you are probably going to blow a head gasket soon. The same thing happened to my old truck. I flushed it out with the prestone cleaner twice and then a month later rusty coolant was spraying out of the engine. When I had the head gasket done, they had to pressure wash my block to get all the rust out. most of the cooling system needed to be replaced also (hoses, heater core, radiator, etc..) Don't mean to scare you, but that's the reality of it.

Hawkflyer

Man that is bull........ all because someone couldn't do the right thing.

KZN185W

iTrader: (1)

yes, the radiator has a drain cock at the lower tank on the right side (passenger side).

the engine also has its own drain cock..its on the right side (passenger side) of the cylinder block.

One_96TR4

I'd just clean it and see how things work out after you clean it. It's a lot harder to blow a headgasket on a 3rd gen than you'd think. ^^ that must have been a 2nd gen.

brian2sun

Yeah, it was my old 3.0 95 4runner that the hg blew on. I hope it's not the same for 3rd gens like One_96TR4 said. Hope the flushing does the trick.

Hawkflyer

Well-

CLR didn't do a thing, but I did something that I will likely kick myself for later, I installed a Prestone flush and fill kit. This REALLY made the job a TON easier, and I was able to flush the water and CLR out rather easily. My crappy Stant brand cap that I bought for it lasted about 24 hours before a it fell apart inside the radiator, prompting me to go to the stealer and get a good one. to their credit, the auto parts store took the old cap back.

Coolant looks good, and I installed Water Wetter, I will flush it again in a few months to try to get rid of as much of that nasty scale as possible.

One_96TR4

Yeh the 3.4 can take a good bit more abuse. Plus unlike the 3.0 the 3.4's don't really have headgasket issues. Apparently 96's had a small problem but I have a 96 and no trouble.

Ritzy4Runner

iTrader: (1)

A shame that the previous owner did not take better care of the cooling system. Also I had a 95 with the 3.0 and I had over 100,000 miles on it with out an issue, but I did have it checked out by Toyota and verified the recall on my motor. When I bought my 98, it seems to have had its radiator replaced and had been filled with the red toyota OEM coolant.

I did the cooling fan mod to my truck (Taurus electric fan mod) and I can tell you that the cooling system on these 3.4 4runners, when taken care of is unreal! Last summer on my trip to SoCal from Washington, I needed to adjust the thermostat controller on the relay module so I used the intermediate position to turn off the fan, to keep it from cycling when I turned it off, well I forgot to turn it back on when I left on my trip back. August, I-5, Los Angeles ... need I say more? long story short, through LA, up the mountain grade and into the valley via the Grapevine, hit the valley floor with temp around 103, just kept right on tooling along at about 65 miles per hour, stopped to get gas in Los Banos and that when I noticed my fan was still in the intermediate position. My temp was rock solid at just under 1/2 on the temp gauge. That red coolant and a maintained cooling system really paid off BIG!

If you can get your engine cooling system flushed and cleaned out, I would look very closely at the cooling fins in your radiator, get it pressure tested and if they appear to be corroded or in poor condition, I'd replace your radiator and fill it with Toyota OEM coolant. The 3.4 is a gr8 motor and like was stated above, they can take a bit of abuse. good luck.

Hawkflyer

I'll have to check out that Taurus fan mod, although I agree the stock cooling system is VERY good. The engine driven fan is so effective I hate to get rid of it.

Ritzy4Runner

iTrader: (1)

The clutch fan system that is stock on our trucks is more then adequate, I only decided to go the electric fan road to get the extra horse power t he fan uses. Yes it isn't that much maybe 2 HP, but that has translated into about 2+ MPG especially on the highway. My last trip to SoCal I got between 22-24 on the flat portion of I-5 and that was driving 65 miles per hour. I don't drive my truck hard like a few on here do so I know that the little bit of horse power does help some.

There are a few different ways you can go on the electric fan mod. I chose the Taurus fan mod as the fans are usually inexpensive, around $20 in most yards as they came out of 3.8 litre Ford/Lincoln V-6 vehicles (Taurus/Sable, T-birds Lincoln Continetal) from the early to mid 90's and there are still quite a few of them around. mine came out of a 95 Taurus. If you go with the later 2 speed fans be sure to get all of the harness which has some sort of electronic control box that was added by Ford in 1995. To replace that controller is like $100!. You need to purchase a controller and there again are more options, varible speed, thermo controlled, pretty much what ever you feel the most comfortable with. I got the TorqFlow from Auto Zone. Thermostaticlly controlled with the relay - $35. I also prucahsed a static contolled relay from the same commpany for controlling the high speed manual override and it was around $20. I know some have opted for a varible controller so you are only using a single speed but varing the load to the fan. These can run upwards of $100.

There are draw backs, depending on where you drive (climate) and where you locate your controller, you can over hear it. I just had to replace my controller as I was starting to have issues with it, but long story short, I replaced it this weekend but overall, I have been very happy with my fan upgrade. It really is a personal preference.

If you do any off-roading with water crossing, with one of these fan mods installed, you can shut off the fan for fording those creeks, then restore full operation. Also the two speed Ford fans allow you to have a manual override to kick the system up to the high speed for added cooling if needed. Search on Taurus Fan mod or Electric fan mod and you will see what has been tried and installed on various trucks here on Yota Tech. Feel free to ask me any questions you may have if you want to attempt this mod. Either way you decide to go in modding your truck or keeping the OEM fan, just be sure to get the issue with your radiator sorted out first. Good Luck!