Coolant Hoses?

[super90]

Did I miss any coolant/heater hoses in my effort to replace them all at 10-years of age?

- Upper and lower radiator hoses
- The six heater hoses and the two plastic T's they connect to
- The "bypass" hose at the throttle body

I'm about to refill the system and wanted to make sure I haven't missed any. I can't fine any more by looking at the pictures on the online parts catalog.

TIA

R.

 

[OregonLC]

There are some hoses down at the oil cooler too.

 

[super90]

Are those coolant hoses going to an engine oil cooler? Or are we referring to the transmission fluid hoses going to the radiator?

Trying to find a schematic...and part numbers....

 

[OregonLC]

The oil filter threads onto a water|oil heat exchanger which is commonly called an 'oil cooler'. There, coolant lines exchange excess heat from the engine oil as it leaves the filter on it's circulation path. There are at least two small diameter coolant hoses connected to it. One is relatively easy to get to from the front, the other goes up to a port on the DS side of the block and is a mother bear. The latter can be done if you use a razor knife to slice the hose longitudinally at the hose barb (after removing the clamp). But, it's a very tight fit and can only be done one-handed.

It seems like there is a third hose down there, but I can't remember for certain.

 

[super90]

Ahhh, Got it.

http://tps.toyotaofdallas.com/parts/2003/TOYOTA/LAND%20CRUISER/?siteid=214074&vehicleid=1418352&diagram=8415065

The "oil cooler". Very different from the one on the 80-series !

Thanks !

 

[OregonLC]

Yep, that's it. And yep, there's the third hose at the top of the pipe.

 

[SWUtah]

I would Do a poll to see at what mileage/years any member had any hose failure, also where they live? Desert, Alaska, Midwest? Just to let you know I did a search and there were no threads that stated anyone had a hose failure. Just saying!

 

[OregonLC]

You're right. There is no case to be made for their replacement. Other than the case of 'while we're in there' or 'it's gonna be 100k before the coolant gets drained again'. But then again, the heater hose tees were a hidden failure until someone figured them out.

 

[SWUtah]

You're right. There is no case to be made for their replacement. Other than the case of 'while we're in there' or 'it's gonna be 100k before the coolant gets drained again'. But then again, the heater hose tees were a hidden failure until someone figured them out.

But heater T's did not fail till they tried to remove them. I am not saying that it is not a good idea, if you are going to keep it for the long haul? Change all the rubber parts, front CV boots, etc.

 

[OregonLC]

That's my point. Removal forced the issue on a part that was close to failure. Had they not been messed with it was just a matter of time before one of those left someone stranded, either at the mall or on the trail.

That said, I found nothing with the oil cooler (or any other) hose indicating a failure was even on the remote horizon. They were all hard and semi-fused to their nipples and without an impact or other extreme adversity I don't see how they could have possibly failed. No plastic parts anywhere.

 

[Kigiin]

Interesting. I am about ready to have my mechanic do the second 90k service and I suggested to him that I am considering replacing all the hoses while he's in there. He said that failure was unlikely, and that these hoses were built to last. I have replaced Ts but am considering not replacing the hoses.

 

[spressomon]

I haven't seen empirical data suggesting when coolant (water and ATF) rubber type hoses should be replaced. But I did replace the upper and lower radiator hoses, the 3-oil cooler hoses and heater tees when I did my first 90k.

The oil cooler hose that runs towards the steering rack from the oil-filter housing/cooler was replaced when we swapped racks...that's the time to get that one refreshed. The other convenient time to replace this hose is at 90K PM and Doug Thorley header install...then its exposed on both sides.

Fast forward to doing my 2nd 90k right now: I'm replacing all the same plus the ATF cooler related rubber hoses (in addition to t-belt, tensioners, idler pulleys, water pump, t-stat, radiator cap, etc.)

My decision to replace these hoses is based upon: #1) The remote locations this rig goes; and #2) in relative terms, the somewhat minor cost of the hoses for the peace of mind they bring to #1.

Probably overkill...but so is just about everything else I've done to this rig

 

[SWUtah]

I haven't seen empirical data suggesting when coolant (water and ATF) rubber type hoses should be replaced. But I did replace the upper and lower radiator hoses, the 3-oil cooler hoses and heater tees when I did my first 90k.

The oil cooler hose that runs towards the steering rack from the oil-filter housing/cooler was replaced when we swapped racks...that's the time to get that one refreshed.

Fast forward to doing my 2nd 90k right now: I'm replacing all the same plus the ATF cooler related rubber hoses (in addition to t-belt, tensioners, idler pulleys, water pump, t-stat, radiator cap, etc.)

My decision to replace these hoses is based upon: #1) The remote locations this rig goes; and #2) in relative terms, the somewhat minor cost of the hoses for the peace of mind they bring to #1.

Probably overkill...but so is just about everything else I've done to this rig

I agree with your conclusions. I mall cruiser around metro Las Vegas, mine has been well maintained by the local Lexus dealer that replaces anything they "think" might be a problem or that makes them more money. If I have mine for the second t-belt service I will also replace all the plumbing.

 

[super90]

Plastic heater hose T's drove this maintenance. I just wanted to replace them after ten years, so might as well do the heater hoses, and .....while I've drained the coolant, radiator hoses, which I don't see listed on the 90K mile service that the PO did, and that bypass hose is easy to get to and only costs a few dollars......etc. etc.

As for the "oil cooler" hoses, I agree, the next 90K service is exactly the time to do them as it's all apart. Trying to get to them now would be far more effort than it's worth.

By the way, I took each group of heater hoses and it's respective T off in an assembled "unit". Once I had them off the truck I carefully took each of the hoses off the T. I had the end of one barb break off, even with the slightest of effort. Continues to makes me believe that every 10 years, I just replace the heater hoses and T's. I've done this with all my other cars at the advise of my favorite BMW shop, and it seems a good practice. It's cheap, easy preventive maintenance.

BTW, here is what the 80-series heater valve looks like after about 12 years, and another reason why I even started this on the 100. Guys had those failing on them at "less than convenient" times. It's the same plastic as the T's. A known problem and why the T's in the 100 were already on my radar.

 

[SWUtah]

Plastic heater hose T's drove this maintenance. I just wanted to replace them after ten years, so might as well do the heater hoses, and .....while I've drained the coolant, radiator hoses, which I don't see listed on the 90K mile service that the PO did, and that bypass hose is easy to get to and only costs a few dollars......etc. etc.

As for the "oil cooler" hoses, I agree, the next 90K service is exactly the time to do them as it's all apart. Trying to get to them now would be far more effort than it's worth.

By the way, I took each group of heater hoses and it's respective T off in an assembled "unit". Once I had them off the truck I carefully took each of the hoses off the T. I had the end of one barb break off, even with the slightest of effort. Continues to makes me believe that every 10 years, I just replace the heater hoses and T's. I've done this with all my other cars at the advise of my favorite BMW shop, and it seems a good practice. It's cheap, easy preventive maintenance.

BTW, here is what the 80-series heater valve looks like after about 12 years, and another reason why I even started this on the 100. Guys had those failing on them at "less than convenient" times. It's the same plastic as the T's. A known problem and why the T's in the 100 were already on my radar.

I did the hose between the engine and firewall on my 1995 FZJ80 when it was 8 years old and had 60k miles on it. That hose is a known issue on the FZJ80's.

 

[LostAfrican]

I have spent some time looking at the FSM and haven't been able to figure out if engine coolant is always flowing through the interior front and rear heater radiators, or only when heat is selected by the controls? When the system is on cool, does the air bypass the heat radiators or does no engine coolant flow through them? Is there a valve somewhere on the coolant path?

The reason I ask is that I am getting ready to replace my "heater T's" and the 6 hoses that connect to them, but I also know that under the truck there are 4 more hoses that I think are for engine coolant to the rear radiator.

If there is a valve somewhere, then at least if I have an issue, I can just turn off the heat to allow the engine to cool itself normally. If not, then I probably should replace those additional 4 hoses (which is going to be tough, because one of the clamps is tucked tight behind an exhaust shield!

On the other hand, if there is a valve, is it plastic like the one in an 80 above!?

I suppose the trail fix (assuming good "T's") is to just loop the heater hose back to the other T at the engine side of the firewall and bypass the entire cabin heating system - which is fine as long as you are not in Alaska or very high somewhere...

Andy

 

[APKhaos]

There is no heater valve controlling coolant flow. Its circulating through both front and rear cores whenever the engine is running.

 

[jemsec]

Folks, listen and take heed from "spressomon". Best advise on this site. He knows his stuff! He'll probably drive his rig for ever.
I wish he lived near Birmingham, Alabama.

 

[ljlc]

Leaking Oil Cooler Coolant hose. I noticed a couple of coolant drops under the truck. looked and looked and couldn't find the source. A week later, viola! The oil cooler coolant hose, I think that it is number 5 on the Toyota parts diagram in the oil cooler section. Truck is a 1999, 236k miles on it, frankly, I don't know if those set of hoses have ever been changed, all of the other coolant hoses have been done at fairly regular intervals. Glad I found it, wouldn't want to loose that one on the trail. Something to consider if you have an older rig. Phil

 

[super90]

Leaking Oil Cooler Coolant hose. I noticed a couple of coolant drops under the truck. looked and looked and couldn't find the source. A week later, viola! The oil cooler coolant hose, I think that it is number 5 on the Toyota parts diagram in the oil cooler section. Truck is a 1999, 236k miles on it, frankly, I don't know if those set of hoses have ever been changed, all of the other coolant hoses have been done at fairly regular intervals. Glad I found it, wouldn't want to loose that one on the trail. Something to consider if you have an older rig. Phil

Thus is on my radar as well and I wanted to do it with all the other hoses but it seems best replaced while doing a Timing Belt as the access is far easier. I'll do it at 180k mi.