View Full Version : New coolant leak

04-19-2014, 01:12 AM
As some of you know I've been chasing/fighting coolant loss since I brought the All Trac back with me from Texas. I replaced the radiator and took care of the problem last month before the Dragon. I drove the car to work for a couple of weeks and no problem. I had to park it for a few weeks because I found both front tire were ready to go.

Any way, I got new tires on this morning. After picking it up, I had to run up to Lowes to pick up a couple of things. When I came back out there was a note on the window telling me I should check the coolant as I was leaking antifreeze. I look down and sure enough a good puddle of coolant on the ground. I popped the hood and looked for obvious leak but nothing. I had filled the overflow pretty far up right before I parked it with the tire and I thought that maybe it had blown excess coolant out.

I drove home with no problem. Temp gauge didn't move from where it normal resides. I parked and went in the house. Come back through and look outside, more coolant under the car. I went out and looked and it had drained down off of the underbody shield on the passenger side. It did not come from the radiator area or the lower radiator hose. The HFH behind the turbo is fine too. Those areas were clean (I've still got leak dye in the system from before). It looks like it came from somewhere on the front corner of the engine.

My question now: other than the other *&#@ bypass hose from the oil cooler, where else could I be leaking? The water pump? I had it replace three years ago when I had the timing belt done and it doesn't have that many miles on it. One thing that does give me pause about the water pump though is that when the guy changed the belt he called me and told me that Denso pump that I gotten (I think Denso. It was the OEM pump from the actual manufacturer.) didn't have the name cast on it like they normally do. It came in the right box but may not have been what I actually paid for. He was in the middle of the job and I need to get the car back so I told he to use it. That may have been a mistake.

Any way, anybody have any ideas? I'm going to jack it up tomorrow and check the underside with black light to see if I can see any of the dye.

This is really starting to piss me off. I want to get back to driving the car regularly but the damn coolant leaks are preventing that big time. I think the next thing I'm going to do is replace all of the hoses on the car. I know the HFH is good and I had to replace a heater hose a couple of years ago. I'm going to the other one as well. One more question. There are a couple of hose on the back side of the 3S as well arent' there?

04-19-2014, 02:34 AM
Reading the description I was thinking water pump as well. Or the gasket, of course. I mean, it could also be that when the pump was replaced, they did a shitty job of cleaning off the mating surface.

04-19-2014, 05:26 AM
I would think they did a good job of cleaning it up if the tech took the time to let him know before install that the pump itself may have been a grey market part.

Mike, there is a hose on the backside of the engine closest to the firewall and half way down that I just had to replace myself last month. Had a tiny pinhole leak in it.
I had the same damn issues you are describing. Think I posted about it. (not sure) Anyhow, only cost me about $150 to have it replaced at a shop. It was a bitch to find and a bigger one to get to. I think Luni said it is kind of "L" shaped?
But I guess that only applies if it coming down around the top of the cross-member in the middle(ish)/trans area of the engine. If yours is definitely leaking around the front cover area, it may well be that the pump is weeping.

04-19-2014, 06:00 AM
I don't really think it's the gasket. The reason I think that is that the pump has been in there three years with no problem. I guess it could have failed but I'm afraid it's more likely the pump.

I haven't gotten under it to take a good look yet, hopefully tomorrow, but right now it looks like it is leaking onto that front underbody cover and dripping just to the right (passenger side) of the center cross member.

Mario, the hose you're talking about was on the back toward the middle? I'm trying to figure out how many hoses are on the back. I've looked at a couple of pictures on EBay & I could see a couple on the driver's side but I wasn't sure if there were more. I really don't understand Toyota's obsession with the damn water bypass pipes & the hoses. They're pretty much nothing but a leak waiting to happen. We still put them on the ZR engines we build now.

04-19-2014, 07:51 AM
Aisin is the Japanese OEM for the water pump. Similar thing happened on my gfs Altima. Grey market part was installed instead of an Aisin and the seal blew within a few weeks. I'd start there if you see dripping on the passenger cover.

04-19-2014, 01:49 PM
I couldn't remember if it was Denso or Aisin. I bought all the parts myself and I specifically bought the Aisin pump. Came in the correct box but I didn't open it and check it. It's been in there almost 4 years now that I think about it. I had it done the first year I was in Texas and that was 2010. I'm going to try to see where it's coming from today.

04-20-2014, 02:41 AM
Well I ran it down the road and back this afternoon. Made a couple of stops. No issues. Get it back home and park. A little late, coolant under the car. I looked from underneath and I can see that it came down that front corner of the engine and the kind of spread around the rim of the oil pan. Laying on the ground, I could see far enough up to see where it originated. Could have been coming out from under the timing cover from the water pump or from that damn by pass hose. I guess I get it to the shop I use and have them check it out on the lift. I really hope this is the last of the coolant issues for a while. I just want to drive.:cry:

04-20-2014, 03:14 AM
i had a similar problem with my 5s in my vert b4 the swap, come to find out the hose that ran to the switch that has the blue cable running to from the inside had a small holein it and the hose would leak when the car got to opt temp. if it is the water pump area, i would redo the hosing as well just to be on the safe side

04-20-2014, 03:16 AM
You'll get it sorted Mike. :) Don't stress it.

04-28-2014, 02:19 AM
Well I did a little more checking yesterday. Fired the car up and got it to operating temp and varied the engine speed up and down for a bit. Right after I shut it down I jumped out and looked. Coolant was almost streaming down underneath. It was coming down over the front of the oil pan. It also looked like there was some coolant on the block between the oil cooler and the back of the water pump housing. Since the coolant was coming down over the front of the oil pan, about two inches from the passenger side from corner, I'm thinking I've got a pass hose leaking. The wonder HFH on earth.

I pulled the alternator off today and I'm getting the thermostat housing off so I can hopefully get to both ends of the hose. This may not be it but I would think if the pump as starting to weep it would be coming down over the side of the pump.

Hopefully I'll get some time and decent weather to get further into in the evening this week. This really looks like it going to be a bitch.

More updates to follow.

04-29-2014, 12:40 AM
FWIW, I believe one of the the oil cooler bypass hoses is what gave me constant overheating issues for months in Houston on my 185. It finally got bad enough to develop into a noticeable leak and tracked it down the very same day I sold it! It then blew a DIFFERENT coolant hose on its way to Kansas with the new owner. Good luck and stick with it.. you'll get it!

05-01-2014, 11:36 PM
Well, I think I found my leak.

http://i304.photobucket.com/albums/nn195/gowron100/HFHOEpic_zps2dc208e2.jpg (http://s304.photobucket.com/user/gowron100/media/HFHOEpic_zps2dc208e2.jpg.html)

Ordered the new hose so I thought I'd see if I could get the old one off. Took all work after removing the alternator, the AC line, the oil filter and the thermostat housing. I'm pretty confident that Toyota hired the engineering department at GM to design this set up. I don't think the Japanese could come up with such an asinine set up by themselves. It really looks like something from GM.

Anyway, from the looks of this hose, this has to be this particular leak. Hopefully the hose comes in tomorrow and I can get it on Saturday morning without too much trouble and be back on the road. Wish me luck. It think I'm going to need it.

05-01-2014, 11:47 PM
glad you found the problem nitro :)

05-02-2014, 03:46 AM
Glad you found the leak! Any photos of the physical location in the engine bay? (I just ask because every little bit of info helps in the future troubleshooting efforts) :)

05-03-2014, 12:09 AM
I'll get one Mario. I have to say that after taking the alternator and oil filter it is possible to get to it. I may have a different story trying to put it back on. This one came off the pipes easier that the HFH BUT it isn't exposed to nearly as much heat. I picked the new one up today so hopefully I can get it on this weekend depending on the weather. We're still getting rain off and on but thankfully we haven't gotten nearly as much as some of the surrounding areas and we didn't have the tornados.

05-03-2014, 01:08 AM
Glad things are still ok out there Mike. Thank you for taking pics when you are able. :)

05-03-2014, 10:10 PM
OK, got the hose on and everything put back together. Filled the radiator and ran it till it got hot. So far, no leak. I'll take it out and drive it tomorrow.

So now, here are a few pics of this fun process. It actually wasn't as bad as I thought it might be.

Here's the new hose. It's much more solid feeling than the old one. It's hard to tell how old the one that came off was, probably original. This engine is a JDM unit that was swapped in two owners ago. It's got about 130K on it (I found the Japanese receipt from the vehicle it was pulled out of. Only had 19K when it came out.)

http://i304.photobucket.com/albums/nn195/gowron100/20140502_193603_zpse78dd1ce.jpg (http://s304.photobucket.com/user/gowron100/media/20140502_193603_zpse78dd1ce.jpg.html)

Here's where the hose goes back into. It doesn't look that bad with the front corner of the engine taken off.

http://i304.photobucket.com/albums/nn195/gowron100/20140502_193041_zps6ac01f43.jpg (http://s304.photobucket.com/user/gowron100/media/20140502_193041_zps6ac01f43.jpg.html)

Here's a close up. The ends of the two pipes are about 1/2" to 3/4" apart. It's pretty tight in there.

http://i304.photobucket.com/albums/nn195/gowron100/20140502_192957_zpsf0d2343c.jpg (http://s304.photobucket.com/user/gowron100/media/20140502_192957_zpsf0d2343c.jpg.html)

Here's the new hose installed and the second clamp getting ready to go into place.

http://i304.photobucket.com/albums/nn195/gowron100/20140503_104934_zpscaf655db.jpg (http://s304.photobucket.com/user/gowron100/media/20140503_104934_zpscaf655db.jpg.html)

Hopefully this takes care of things for a while. I think the only other hose that should probably be replace are one of the heater lines (I had one spring a leak while I was in the Hill Country in Texas at night. Big fun) and that water by pass hose on the back. I'm going to do those soon so that is one less thing to worry about.

Oh, and DEGREASE the freakin engine.

05-04-2014, 04:52 AM
Great Job Mike. I don't envy you the job of getting that done. :P

05-04-2014, 02:16 PM
It wasn't as bad as some have written. The thing with these two by pass hose (HFH and HFHOE) is that there is no quick easy way to change them out. You have to disassemble a good part of the front of the engine to get down to them. It's not an easy job but one that you can do if you've got some mechanical skills and have done some wrenching before.

Personally I would have rather liked Toyota to have run threaded hard lines into the oil cooler. I know that they used the rubber for service purposes but it makes for a weak link. I don't know about others, but the only time in 8 years that I've had the oil cooler/filter base loose is when I did the Berk downpipe.

05-04-2014, 09:36 PM
I had a buddy that used to always say that sometime way back in the day, a mechanic slept with an engineer's wife, and the rest is history :hehe:

05-05-2014, 11:11 AM
^I'd say that's about right.