2016-03-03

Posted at 22:30 UT by Tamara

This Old Car - 1994 Toyota 4 runner - Radiator repairs

We now have a 1994 Toyota 4 runner, which is a 2 wheel drive automatic, that we are featuring in the series " This Old Car!".

Our first needs have been replacing all the hoses from the radiator, which were all the original Toyota parts and have lasted over 20 years.

The best quality of parts for your vehicle is almost always the factory suggested parts, and Toyota of Santa Cruz is being featured for the main radiator hose being replaced, as well as the lower fan shroud and clips which were missing from the vehicle.

It is most likely, the lower fan shroud was not replaced by some previous mechanic, rather than being stolen or falling off.

Marc S. Lucas came recommended to us, and has a small shop in Felton.
He was the first mechanic who noticed the fan shroud was missing.

He also was the first to notice the radiator clamp was loose and needed to be soldered back in place to prevent the radiator from moving about.

Marc began by placing a large fan on top of the motor to assist the engine in cooling down.

After 5 minutes or so, he grabbed a wrench he had specially notched to fit the clamps of the main radiator hose.
His background of working with a tool and die maker has given him abilities to create his own tools.

He believes the original clamps Toyota puts on their hoses to be the best, as they always adjust themselves to keep a tight fit, unlike the previous mechanics who replaced the heater hoses, destroyed the original clips when removing them, and replacing them with the type of clamps you see frequently in plumbing applications, which will require monitoring and tightening.
We will be looking into replacing those clamps as a result, with the original Toyota clamps.

The end of the hose attaching to the radiator was left in place with the hose pointing upward to prevent fluid leaking, as an extra means of allowing heat to dissipate from the radiator.

We began by first opening up the drain at the bottom of the radiator to drain off fluid having a large basin to capture the fluids.This did not begin in earnest until the radiator cap was removed.

Once the fluids had drained adequately, Marc began the process of grinding/sanding off the metal where the soldering of the joint was to occur.
This allows a clean union for the flux and solder to be applied.

He followed with using an acid wash, and a detergent wash on the area.

He checked to make sure no pinholes or weak spots existed on the radiator.

Using a torch, he then preheated the area, applied some liquid flux, then solder with also had flux in it.

The grinder was used to remove any extra solder.

Now that the radiator was stable, the main hose was removed, the new hose fitted on with the original clamps fitting just behind a small ridge that exists on the radiator outlet, and the other pipe the hose fits on. This ridge helps the clamps further to hold in place and not slip off.

All the fluid was poured through a sieve which consisted of a simple cotton towel and looked to be clean, as it was only 2 weeks old from the prior replacement of heater hoses. Most mechanics just throw away the liquid and sell you new liquids. We liked Marc's filtering process better.

All the hoses should have been replaced at the same time, as they were all over 20 years old and wearing out, but the prior 2 mechanics who had each done a little, but not all, were remiss. It is the purpose of this article, this series, to help educate the public to be knowledgeable enough to recognize if their mechanics are conscientious. If they are not, hose failure will shortly occur and radiator fluids will be spraying the entire engine compartment.

The next step was to restore the bottom fan guard, an arched plastic piece that helps the fan keep the radiator cool, and which had been left off by some previous mechanic most likely.

A matt on the ground makes this job more comfortable and clean, and with the aid of a small flashlight, the guard was replaced with 2 metal clips that fit into grooves, and audibly can be heard to click in place when seated correctly.

The radiator fluid, in this case Prestone, a light green colored fluid and an American Made Company and product, was replaced in the radiator.

Next step was applying some pressure to allow all the bubbles to be driven out of the system, which we could see at the top of the radiator where a plastic basin device had been attached that allowed all the air to come bubbling out. Once no more bubbles occurred, the device and attachment from the radiator cap were removed, having allowed the fluid level to drop back down to the top of the radiator.

It is critically important never to add water to your radiator, as in short time, this will cause the radiator insides to rust.
Only in dire emergencies when all fluids have been lost, due to some mechanical failure, is water only used to get you to the nearest service station where the proper radiator fluids can be replaced.

I know of many people who have topped off their radiators with water. Keep your radiator fluid with you at all times in the trunk of your car.

Our radiator cap is rated according to Toyota specs, at 15 pounds pressure. For every pound there is temperature degree variance and using the wrong cap with the wrong pressure can overstress your radiator.

We started the engine to check on the fan operation, and Marc used a red laser beam device to check the various parts of the radiator for temperature variance. 126 degrees was noted on the outer areas and 86 degrees in the center which suggested that there might be some blockages in the radiator needed flushed and cleaned out.

Final step was attaching a pressure device to assure that no leaks were occurring.

Our next procedure may be to have a radiator expert flush and clean the tank.

We were informed that the radiator would need to be removed from the vehicle for a proper, conclusive procedure.

Radiators in the original Toyotas are metal and pricey - around $400.00. They are, however, the longest lasting ,compared to the plastic ones at a cheaper price, usually made in China.

We would like to ascertain we need replacement, so will be investigating further the radiator flush.