4runner eats radiators

When I got my ?92 4runner (6-cyl 3VZE, stick) 3 years ago, I noticed a radiator leak and replaced the radiator. Now I have a leak in the new radiator.

The coolant was changed about 6 months ago when I changed some hoses and I noticed some scale build-up inside the radiator. I¹ve heard that electrolysis can cause this so here¹s what I¹m trying this time around:

-new radiator

-sacrificial anode radiator cap

-distilled water instead of tap water

Any other suggestions?

TIA, Felix

Reply to
Felix Ideo
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4runner eats radiatorsThis seems to be a common problem with the v6 4Runners. I'm on my 3rd radiator w/90K on a 95 4Runner. The first radiator gave it up just after the warranty ran out. The dealer said he would help me out, marched me into the parts department and told them I needed a new radiator. They told me it was $800 installed. I left and went to a radiator shop and tried to get a new top tank. Without looking at the radiator the owner told me exactly what was wrong and then told me he had no more top tanks to fix it with (there aren't too many radiator shops on the island of Guam). Seems he had seen just a few Toyotas with the same problem. Replaced the radiator with a Modine from Napa. Again the radiator leaked from cracks around the filler neck. Modine did nothing for me on my "lifetime" warranty. Napa on the other hand replaced the radiator for free.

Whatever you do, save any paperwork you have from repairs. Chances are you will be needing them later.

-When I got my '92 4runner (6-cyl 3VZE, stick) 3 years ago, I noticed a radiator leak and replaced the radiator. Now I have -a leak in the new radiator.

-The coolant was changed about 6 months ago when I changed some hoses and I noticed some scale build-up inside the radiator. I've heard that electrolysis can cause this so here's what I'm trying this time around:

--new radiator

--sacrificial anode radiator cap

--distilled water instead of tap water

-Any other suggestions?

-TIA,

-Felix

Reply to
Andy K.

The "I'm not a mechanic so take everything with a grain of salt" reply from me is to check and make sure as well that your engine is properly grounded. Seems like I read somewhere that not having it properly grounded could increase the electrolysis effect. Like I said, not a mechanic, don't really know what I'm talking about and its a third hand, foggy rememberance LOL!

Chris whitewall junkie Mfinja's Hot Wheels with WhitewallsAll Small Wheels Error Cars

Reply to
Whitewall Junkie

Ok, Andy, I'll take your advice as "fair warning." The radiator that just gave it up was a Modine also. Shop I bought it from said that Modine will pass judgment on whether it's a manufacturer's defect. So, I don't have much hope in a free replacement but I'm going to try.

Maybe us 6-cylinder owners should just include a new radiator along with changing the coolant in our every-other-year cooling system service.

Felix

Reply to
Felix Ideo

Actually, this is not a bad idea. The guy at the parts store told me the electrolysis is caused by static build-up from the moving parts in the engine. If this is true, maybe a good path to ground would help get rid of the static and reduce electrolysis.

Thanks, Felix

Reply to
Felix Ideo

Oh, easy one, you have too much arsenic in the drinking water. Its those evil republicans. Did the problem show up after GWB in 2001? And that tax refund wouldnt of even bought a new radiator with installation. I bet no one had any failed radiators during the Clinton administration. And you need to dump that evil SUV also, with the extra size of that rig, did you know your increasing your chances of being hit by a meteor?

Move way left and vote for me, I know, I'm a nut job, but I can do it, I'm sure I can!

Reply to
Howard "Nakita" Dean

I'm talking about and its a

You may be onto something. I recall from my auto class days you could take a voltmeter and measure between ground and another lead in the water of the radiator. If there was any voltage above 0.2-0.4 volts, you needed a change of water and a better ground to the radiator. The voltages may be off a bit but I remember them being quite low for the voltmeters of that era.

BP~

Reply to
B. Peg

Hadn't realized you could actually measure voltage from ground to coolant. I'll install a ground wire from radiator to chassis and see if that helps. Thanks for the insight.

Felix

Reply to
Felix Ideo

.3 means trouble. Just change the coolant is all.

Reply to
MDT Tech®

Hey, are those my poll numbers?

Reply to
Howard "Nakita" Dean

It's not static build-up. That's what causes the lint to collect between the ears of the parts store guy.

Grounding is necessary because of all the electrical apparatus that uses the engine as the negative current path, and there might not be a good circuit through some gaskets, rubber engine mounts, etc. In this case, ground heads and block to the body. A voltage difference between parts, even .3 volts as MDT Tech said, can cause electrolytic corrosion (electrolysis). Also, the different metals inside an engine, iron, copper, different aluminum alloys in the heads and radiator, can cause galvanic corrosion, a form of electrolysis.

Antifreeze contains corrosion inhibitors including materials to keep it from becoming acidic and allowing more electrolytic corrosion. These inhibitors become depleted. Renew your antifreeze every two years. Guam?...you can get some anticorrosion stuff to mix with water, don't need antifreeze, but it also becomes depleted and needs to be renewed.

Ken

Reply to
Ken Shelton

LOL. Sounds like he was maybe 90 degrees off.

I'll take a voltage reading now with fresh antifreeze/water and maybe check again in a year and see what the difference is.

Many thanks, Ken. You guys are a wealth of knowledge!

Felix

Reply to
Felix Ideo

Ford had a problem with repeated heater core failures on many different car lines because of electrolysis. I'd guess metal radiators could suffer from the same problem. Ford recommended the following:

"Electrolysis Inspection

"If there is a condition of a heater core leaking or repeat heater core leak, check for electrolysis using the following procedure:

"To check for electrolysis use a DVOM set on DC volts. Place the positive probe of the meter in the engine coolant and the negative probe on the negative battery post. Adjust engine throttle to 2000 RPM to properly get coolant flow and true electrolysis voltages. If more than .4V is recorded, flush the coolant and recheck. NOTE: EXPORT MARKETS, BE SURE THE WATER IS DESALINATED.

If there is still excessive voltage present in the coolant, check the engine to body/battery grounds. Also, verify proper grounding of any aftermarket electrical/electronic equipment which has been installed into the vehicle. Improperly grounded electrical devices can cause electrolysis to occur. If the condition is still present after the grounds have been checked, it may be necessary to add extra grounds to the heater core and engine. A hose clamp can be used to secure a 16 AWG stranded copper wire to the heater core inlet tube. The other end should be secured to an EXISTING FASTENER on the body sheet metal. Extra grounds to the engine should be attached between EXISTING FASTENERS on the engine and body sheet metal. Verify continuity of any added grounds to the negative battery terminal. If the condition is still present, add a restrictor (part F1UZ-18D406-A) on the inlet hose with the arrow facing the direction of coolant flow (toward heater core). Cut the line and install with 2 hose clamps. It is important that the restrictor be installed in the right direction of flow and as close to the engine block as possible (not near the heater core itself).

Your problem may be different, but this is at least confirmation that electrolysis can cause cooling system problems - especially in systems with dissimilar metals.

Ed

Felix Ideo wrote:

Reply to
C. E. White

Ed, Thanks for the detailed Ford report. I can see now this is a problem that plagues many different cars and is not make-specific.

It does make me wonder, though.... why is my heater core lasting this long? Maybe I better knock on wood and expect a leak any day.

Thanks, Felix

Reply to
Felix Ideo

Electrolysis can be funny stuff. Most newer Fords use aluminum radiators with plastic side tanks while the heater cores are all aluminum. Because of the smaller size, water flow velocity, and the relatively poor grounding of most heater cores (an aluminum part surrounded by a plastic case with lines isolated from the body, I would suspect that heater cores are especially vulnerable to this problem. It has been a long time since I had a heater core fail, but then I change my antifreeze at reasonable intervals.

Ed

Reply to
C. E. White

I thought I would chime in here on this electrolysis thing. I have a

91 Chevy pickup. I had to replace the factory heater core about 11 months ago. It failed this summer and I put another one in. I just got back from the local Chevey dealer where i got yet another heater core to replace the one i put in this past summer. This is one of two posts I've seen about grounding the core and checking the other grounds. Altough this post, or thread, has more info than the other did. And this seems to be a problem with 90's model chevy trucks. I wanted to get "chevy" into this thread, so others searching could find it. I don't see, however, how just changing the coolant would do much good. If you have current flowing in the coolant, need to stop it.
Reply to
noel

Pure water is not a particualrly good conductor (but add a little salt and some acid and it is oh so good). Contaminated coolant with depleted anti-crossion additives makes a much better electrolyte than fresh water plus antifreeze. Think weak battery acid.

References:

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Ed

Reply to
C. E. White

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