iamsuperbleeder

So Thanksgiving weekend I drove south to be with family. While I was visiting, it was time for an oil change so I took it to a local place down there that my father vouched for and he takes all 3 of his vehicles to. After the oil change, they told me my coolant was a little low and it looked like it was leaking from the water pump I checked the coolant and sure enough it was low; maybe 4 or 5 inches under the full mark. I KNOW it was full about 2 months ago because I put a brand new radiator cap on it because it started leaking; could tell from the run marks down the radiator under it... Glancing down the front of the motor, I can't see any really noticeable signs of leakage, but there does appear to be a very small spot near the bottom of the front of the block where it looks like some coolant may have been pooling. After a week of driving, I checked the coolant again and it doesn't appear to have leaked out any more, so it's a VERY slow leak.

I did a little Google'ing, and apparently it's not all too uncommon for these 4.0's with under 70k miles on them to spring a slow leak from the weep hole. Mine has 73k on it, so I guess I should feel fortunate, lol.

I'm going to watch the coolant over the next couple weeks and see how it goes, but if it starts drinking the coolant quickly, it'll get changed; that pink coolant is $20 a gallon from Toyota... have half a gallon still left over from the radiator cap incident, but still...

Just curious, if this is as common as it looks like it is, has anyone here had this happen to them and had to replace the pump? If you've replaced the pump, have any recommendations on a quality pump? I've seen Rock Auto sells an Aisan pump, what's basically OEM, but if it's only going to last another 60k-70k, there's got to be something better...

2big4arunner

From my experience with Toyota and coolant pumps in general... go factory. Its the only one designed to do the job.

BMcEL

I'm pretty sure they are all designed to 'do the job'. Who would buy parts that didn't 'do their job'?

OP - if Toyota hasn't made any changes to the original pump, why not go with a reliable aftermarket source like Napa or the Southern equivalent.

2big4arunner

Everyone takes the original pump and tries to copy them. So some might work, some might be better but I have ALWAYS found the original pumps to work the best. Aftermarket just doesn't spend that type of money on testing.

If you want to try and twist the wording to make yourself feel better. Think about how much of a jackass you sound like when you do it.

Swimmerboy2112

iTrader: (2)

I am a tech at a Toyota dealership.

Toyota claims the seeping or weeping that you are experiencing is "normal" because the system is pushing out debris out of the weep hole.

I would try completely flushing your coolant, to remove the debris.

If it turns out your water pump needs to be replaced, DO NOT use anything other than an OEM water pump. I have seen too many non-oem pumps fail prematurely.

-Brian

BMcEL

They are copies. I don't think any reliable aftermarket parts company in their right mind would re-engineer a water pump without testing it. The issue is in the materials used, not the design.

If you want to try and twist reality to make yourself feel better, feel free.

donomite49

timing belt and water pump time?

i'd stay with oem aisan, toyota uses them for a reason...

2big4arunner

Well I see that a couple more people including a Toyota Tech agree's with only going with the Aisin pump since they are the best option. I am not saying that an aftermarket pump wouldn't do the job. I am saying that they dont "BETTER" a pump and sell it for less.

This engine also has a timing chain and even though I haven't looked that hard I believe its a serpentine driven water pump. For the original poster incase you dont have it here is the routing diagram



http://i1265.photobucket.com/albums/...eserproute.jpg

iamsuperbleeder

Guess it's unanimous; Aisin pump it is. As you so elegantly put it, "they dont "BETTER" a pump and sell it for less", lol, which makes perfect since.

It is in fact a serpentine driven pump; the fan clutch is bolted right to it and driven on the same pulley. Which brings up another opportunity for upgrade, and electric fan, but we'll see how funds are looking at that point. Doesn't really need it, but might get a little more MPG and would just be less strain on the motor without the mechanical fan. I wouldn't expect the gains like I got on my 22re in my 91 when I did it, but it would certainly help; if anything, it'll be less noisy.

The 1GR FE is a timing chain motor, and what's odd is that there's no predetermined interval that you're suppose to change them at; basically just change it when it begins making noise, lol. So I'm not going to mess with that, but what I WILL probably do is change the spark plugs while I'm in there. I'm not sure if it's ever been done, and it's got a little random "kick" in the idle that I noticed. No codes or anything, but again it couldn't hurt.

I THINK the serpentine belt has been replaced once in the past though; it has a Gates belt on it right now.

I'm going to ride it for another week or so and just keep an eye on the coolant level and go from there. If it starts to drink coolant, I'll order the pump and plan a day under the hood

2big4arunner

Thank you for the comment superbleeder. I put it in a different post but I just did the thermostat on my 4.0 and it made a big difference even though I wasn't overheating. Those things do wear out and cause it to cool continuously instead of maintaining temperature.
I might also suggest a Stereo Capacitor for your electric fan swap. It lowers the draw on the alternator and takes the initial impact off your engine/alternator. You can run duel high output fans and never notice when they start. Less load on the engine again and betters the fuel economy even more. I know its an older engine but I got close to 2mpg out of a 3.0 auto v6 doing this. Along with a temp sensor activation kit I Used two ford taurus fans from picknpull and a 2 farad capacitor from Visions electronics. Only difference on the kit installation is running the power to the fan from the capacitor instead of the battery/alternator. Just dont buy the cheap capacitors if your going to do this since they dont have the amp load ratings that they brag about. nothing under 100 bucks brand new or its just crap and will break. total with the Capacitor that I bought brand new was 250 bucks (rounded up to nearest 10 with our 12% tax)

iamsuperbleeder

That's an interesting idea; never heard of using a capacitor for the fans, but that does make since. With the single 18" fan I had on the old 91, the headlights would dim and the engine would seem to strain for a second when the fan kicked on.

I went with just a universal aftermarket fan and a stand alone temp activated switch (as well as a 3 position override switch in the cab) when I did the 91, but considering where I work now (a scrap yard ) I'll keep an eye out for something that may be a good fit.

j2the-e

Yup. "Normal" in some cases. Files too big for me to post here. Try searching
Toyota T-SB-0117-11

rworegon

Some Toyota water pumps are now designed with a debris ejection path that may some leakage under normal conditions. Interesting......

T-SB-0117-11 pdf

Water Pump Inspection and Diagnostic Tips
Issued: 9/1/11

Applies to:
2003 – 2011 4Runner
2005 – 2011 Tacoma
2011 Highlander HV
2008 – 2011 Highlander
2006 – 2011 RAV4
2007 – 2011 Tundra

Excerpt:
"Temporary Leaks
If debris becomes trapped between the mating ring and seal ring a small gap is formed. This allows
coolant to bypass the mechanical seal, flow into the fluid catch pocket, and drain out of the weep
hole. This condition is temporary and will no longer be present once the debris is crushed or works
its way out of the seal. Water pump replacement is not necessary.

If debris was trapped between the seal ring and mating ring an abrasion mark may have been left
on the mating ring surface. This abrasion mark does not affect sealing performance due to the
large sealing surface of the mating ring. Once the debris is no longer present the mechanical seal
performance will return to normal operation. Water pump replacement is not necessary."