Substantial coolant leak somewhere under upper air intake manifold (1 Viewer)

[Aloha Jen]

After returning from an hour long drive (with AC on high, but no steep hills or high speeds) I noticed coolant raining down underneath the truck from around the firewall area.

When I popped the hood, the coolant was very difficult to see where it was coming from. Best I could tell it was coming from under the upper air intake manifold (#2 thanks @cahil for the photo)

The leak looked like it was coming from above where I think the PHH is, but I am not 100% on that. There seems to be dried coolant splatter around that whole area, and quite a bit even as far forward on the new oil filter I just put in, but the leak is more toward the firewall.

This may or may not be related some recent coolant loss/possible head gasket related issues I posted in the last few weeks, but might help to explain where the original leak was.

Will I need to take that upper air manifold off to find the leak? I don't think I can get up to underneath it from under the truck? I would really like to fix this myself, but it may be above my skill set....but with the amount of coolant raining down, I don't think I could even drive it to a mechanic, so I think I need to fix it myself. If it's the PHH or some other coolant hose back there, is this something a newb amature mechanic in training could tackle if I had to remove that manifold or any other complicated part? From the research I've done, a lot of guys on here have said that the PHH and other hoses in that area are some of the hardest things they have ever fixed, so the more I read about this repair the more I get intimidated by it. Thanks for any suggestions/moral support. Let me know if I am way off on my amature self diagnosis.

 

[NLXTACY]

PHH would be my guess. Remove the DS tire and just go after it. Don't bother trying to take it out in one piece.

 

[george_tlc]

There's 2 coolant lines under the intake area. One is the PHH and the other the throttle body hose. Both hoses are into the side of the block. Looking in from the DS wheel well (remove the skirts on the inside fender) the bottom right is the PHH and the one up and to left of the PHH is the throttle body hose. Either can deteriorate and leak.... Lots of write ups on doing the PHH. It's pesky only in terms of being in a tight area to work with, nothing technical... The throttle body hose is equally (or maybe more?) painful to get at.

REMOVE the knock sensor near the PHH BEFORE you work on the hoses - or you'll likely break off the connector and then more $$ pain commences.

cheers,
george.

 

[08720]

There was just a post about this recently with a guy traveling home with his new 80. There is a hose that circulates coolant through the intake (that you wouldnt even need in Hawaii as it is for cold climates). There are also lines mounted to the firewall coming up from PHH hard pipe to the plastic heater valve. Check these connections as well as they would be the easiest to replace. Ill see if I can come up with the coolant line diagram to help you visualize it. George and Joey beat me to it so sorry if I mucked up your thread with repeat advice.

 

[retrofive]

^^^^^ What they said.

 

[08720]

This may help.

87245A is the PHH for reference and you can follow that hard line up to the 87240 heater valve that is mounted to the firewall. This pic doesnt show what George was describing (manifold line) but should be able to piece it together. The bottom part of the pic shows the rear heater lines (which you also dont need).

Also check that short 87245e pipe. It goes to your heater core and connects at the firewall.

 

[Dan C]

That is exactly where mine spewed coolant when the PHH popped.

It is a PITA to reach, but not impossible. Place on jack stands; remove the front driver side tire, and inner fender skirt. Once those are out of the way it is much easier to get to. This also makes it easier to inspect to ensure thats your problem.

The hose itself is only maybe 2in long and connects directly to the block then into a metal coolant tube which runs up behind the engine. The tube is connected to another hose which connects to your heater control valve at the top of the firewall, directly behind the EGR valve.

Some Mudders replace just the faulty little piece of hose (this being the most tedious method of repair), while others bypass the metal coolant line by running a longer piece of hose directly to the heater valve.

I would say its only a job...

 

[george_tlc]

Here's the diagram of the throttle hose (named #1 water bypass hose), pdf attached.

cheers,
george.

 

[LFD2037]

I say throttle body hose.^^^^^

 

[bloc]

IMO the rear throttle body hose is simpler, mainly because it is mostly basic disassembly and reassembly. Sure, getting the clamp onto the block-side of it is a challenge, but nowhere near as difficult as most steps of the PHH job. Even removing the hard line for the PHH to make future work simpler was a TOTAL pain.. Getting at the bolts for the hard line bracket on the manifold was really tough. The PHH itself with the hard line in place is extremely frustrating.

 

[Dan C]

Getting at the bolts for the hard line bracket on the manifold was really tough

Or you could just "COUGH" twist it back and forth and "COUGH COUGH" break it off

Not sayin I know a guy, buuuut....

 

[Dan C]

Here is a link for all your PHH fixes. They took the frustration out of sourcing the required parts and put them into a kit. Enjoy

80 Series | Archive | Toyota 80 Series Land Cruiser and Overland Gear.

 

[08720]

Why remove the tube? It can hang out there forever with the bypass and confuse the heck out of the new owner years later which will generate a new post "what is this tube and why is it not connected to anything"

 

[08720]

If it is the PHH you could be at an advantage with your slender smaller female arms/hands. It was easy enough to do as Joey suggests but I walked away with scraped up hands/knuckles. You can in a sense remove the "Pesky" part out of the name and enjoy Mud bragging rights!

 

[NLXTACY]

Well, I was smart enough to realize that there was no way I was going to go thru that he'll do I paid a mechanic to do it. $85 for everything. I'd rather do a birf job than the PHH.

 

[Dan C]

I would rather give Birf , than do either or these jobs.

The thread may have just derailed..

 

[LS1FJ40]

Well, I was smart enough to realize that there was no way I was going to go thru that he'll do I paid a mechanic to do it. $85 for everything. I'd rather do a birf job than the PHH.

What is this PHH that all speak of?!?!

 

[NLXTACY]

What is this PHH that all speak of?!?!

It's right next to the horsepower your missing.

 

[Aloha Jen]

Thank you so much for all of the responses! Following all of the cooling system diagrams I was sent, I am still trying to find the source of the leak. It is definitely not the PHH, it definitely looks swollen and crusty and probably should be replaced, but the coolant leak is coming from above it. The leak is dripping down from the lower portion of the intake manifold (I think) and dripping down past the PHH by about 3 inches toward the front....does that make sense? So it appears to be coming from somewhere just underneath the upper air intake manifold (first post, #2 in the photo). It only starts leaking when the engine is turned on and the car warms up a bit, but it is impossible to see where its leaking, even when I climb up over the boiling hot engine to see around the manifold. I cant really see from the diagrams if there are other hoses in the area where I think the leak is coming from. Any ideas of other problematic coolant hoses around there? Sorry, it is really hard to get photos in those tight places. Thanks again for any suggestions.

 

[george_tlc]

Like I wrote.... throttle coolant hoses. They would leak from higher up than the PHH. From what you just wrote, seems likely that is where you leak is coming from.

Check the hose into (and there's one out of) the throttle body too. They would cause a leak from up the top area of the intake.

cheers,
george.