[brider]

Good news: I started it up with the cap off the overflow tank, let it get good and hot, and there was NO evidence of bubbles, swirling, discoloration, or exhaust smell in the overflow tank.

Bad news: BRAND NEW upper rad hose blew out right at the temp sensor while following the wife and kids up to Maine a week ago, 40 min from home. SECOND time she's rescued me on the side of the road due to an upper hose blowing at the exact same spot, where the sensor boss is bonded to the main hose.

My wife is NOT and understanding person, and did not hear my explanations of it being a hose problem. To her, it's another indication that my beloved LWB is a POS and I need to sell it.

For the record: This is the THIRD time in the 15k miles I've owned the truck that the top hose has blown. Second time, I was able to stop the truck, let it cool, and fixed the leak at the temp sensor boss on the hose with some of that amazing rubber tape that vulcanizes to itself when wrapped and stretched. That repaired hose lasted 10k miles until last weekend, when I decided to play it safe and install a NEW hose. Now I'm back to the repaired hose.

So today I checked for visual indications that the head gasket has blown and is pressurizing the coolant, and tomorrow I'm having a shop do a "sniff" test to detect exhaust in the coolant.

If this sniff test comes out negative, could my recurring problem really be due to a bad coincidence of bad upper hoses? What are the chances of that?

Truck has never given indications of overheating, temp guage is always vertical. I can change the thermostat, maybe even boil the radiator, but if either of these were suspect, wouldn't it overheat?

 

[76FJ55]

have you replaced the radiator cap? it could be that it isn't venting correctly when the system reaches the designed opperating pressure.

the head gasket could still be compromised and only leaking when the cylinder pressures are higher when the engine is under load.

seems unlikely that youwould have gotten 3 bad hoses but guess it is possible.

 

[nkg]

Hello,

Does the top hose remain solid after the engine has gone cold? If it does that is not good. Somehow gases are getting into the cooling system. Could be head gaskets or slipper liners.

I kept driving my 93 4.2 until the heater matirx split. Water everywhere, worst off it trashed the original radio. Time for an engine overall to see if the block or heads are at fault.

NKG

 

[brider]

Time for an engine overall to see if the block or heads are at fault.

NKG

Still waiting to do the sniff test (tomorrow). Top hose does not stay firm when engine is cool.

Being an optimist, I predict the exhaust-gas test will come out negative. Then I'll replace the thermo and coolant tank cap.

 

[brider]

More good news...

The test came back negative for exhaust in the coolant.

So now I'm going to change the thermo, change the coolant tank cap, and come up with a design change for that upper hose...

 

[Funrover]

Same exact issue in the wife's 93 LWB. One hose I simply filled it up let run in the parking lot. Started to drip lightly from that same spot. The 3rd hose has held for a few weeks now. What brand hoses did you buy?

 

[brider]

Cannot recall exactly what the make of the latest hose to blow was...UNI? UNO? Couldn't even tell you where i got it, Rockauto? it sat in my spare parts bin in the truck for well over a year until I decided to install it before a long family road trip.

I haven't replaced the thermo because the shop that tested the coolant gas said all indications are that the thermo is opening and the WP is pumping fine.

The replacement tank cap is WAYYYYY too expensive for me, so I did the classic trick of loosening the cap SLIGHTLY, so that on an extended hwy run the cap only seeps a small amount, yet the dreaded top hose is nicely compliant and not-hard. Temp is remaining normal.

 

[roverandom]

It's the heads and head gaskets, I'd bet money on it.

I understand HG replacement is quite involved and nobody wants to it just for fun but all roads lead to Rome, or in the case of the Rover V8.....the heads.

I lived in HG denial with my Rangie for several years before finally accepting the inevitable conclusion that the gasket must be intermittently leaking somehow, and pressurizing the system.

Mine displayed almost the exact same symptoms and passed every traditional HG leak test known to man so it took me a long time to nail it down. It was also intermittent as sometimes I could drive around normally for weeks between "eruptions" and sometimes it would happen every day. My unwillingness to embrace the facts cost me several sets of hoses, a heater core, carpet, tank cap, radiator re-core, thermostats and untold gallons of coolant. Not to mention about a year of not trusting to drive the vehicle very far.

In the end I got so tired of the unreliability I finally pulled the heads to take a good look and found the gaskets to compromised only very slightly but what I believe the main problem was the heads themselves were quite badly warped with some of the stupid torque-to-yield head bolts loose.

I had the heads machined true and pressure tested, fitted ARP studs and new gaskets and have not had any problems since.

I wish I had pulled the heads first of all and saved myself all the extra aggravation.

 

[Beartech]

My 93 RRC split its upper radiator hose at one end, so I got a new one from Carquest. The problem was getting the coolant sensor screwed back into its mount in the middle of the hose (yay for another candidate for the dumbest engineering on a RR!). The stationary part that is glued into the hose has a very narrow surface where you put the wrench, so you need a really thin wrench. Or you hold it with pliers and hope you don't tear the seal at all. I did the latter as I did not have a thin wrench. That day it blew out where the sensor mount was glued in. Bad hose? Maybe. I got a new one but they had to order it. In the mean time I put in the same hose, but one without the sensor mount. The sensor in the hose is used to decide if the AC can be turned on or not. It is not the sensor that the onboard cpu gets temp reading from as far as I can determine from research of the issue. I plugged the sensor back in and just rested it on the block where the upper hose goes down into the top of the engine (right near the other temp sensor). It gets a temp reading, my AC turns on, and everything is happy! I still have the replacement hose with mount that I got from the auto parts store as a warranty replacement, it is sitting in my tool box. So, just another perspective on those upper rad hoses with sensors.

Of course I hope my coolant system wasn't over pressured due to a leaking head gasket. This week it started losing coolant somewhere in the radiator. So today I'll be doing a removal to see where the leak is. Think happy thoughts for me!

 

[brider]

It's the heads and head gaskets, I'd bet money on it. My unwillingness to embrace the facts cost me several sets of hoses, a heater core, carpet, tank cap, radiator re-core, thermostats and untold gallons of coolant. Not to mention about a year of not trusting to drive the vehicle very far.I wish I had pulled the heads first of all and saved myself all the extra aggravation.

There's iron in your words of foreboding, Roverandom. Although I think I've solved my problem, I, too am afraid to drive long distances with my family in the car, mainly because of the fear of the wrath of my wife if it DOES fail again. That's no way for a man to live.

The sensor in the hose is used to decide if the AC can be turned on or not. It is not the sensor that the onboard cpu gets temp reading from as far as I can determine from research of the issue. I plugged the sensor back in and just rested it on the block where the upper hose goes down into the top of the engine (right near the other temp sensor). It gets a temp reading, my AC turns on, and everything is happy!

Can anyone verify if this statement from Beartech is correct? I considered using a straight-hose and just resting the sensor on the intake manifold, just as he did, in order for it to recieve a "hot" reading, but I assumed it was for the engine ECU for fuel mixture. AC? Mine has never worked, I could do without that sensor...

 

[pazzo rover]

Yes, the coolant sensor (PRC3505) that lives in the Upper hose (ESR2167) controls the AC condenser fans. The sensor for the ECU is ETC8496 Sensor Temp (Ects) (Part # ETC8496) - Land Rover sending units from Atlantic British.

Probably wouldn't be my first choice to let the sensor hang. One option...Go to a salvage yard, or order a new thermostat housing (ETC6135) Thermostat Housing (Genuine Part # ETC6135) - Land Rover cooling/heating from Atlantic British WITH the threaded bung for the sensor. Then run the "straight hose" ESR3297

 

[brider]

Yes, the coolant sensor (PRC3505) that lives in the Upper hose (ESR2167) controls the AC condenser fans. The sensor for the ECU is ETC8496 Sensor Temp (Ects) (Part # ETC8496) - Land Rover sending units from Atlantic British.

Probably wouldn't be my first choice to let the sensor hang. One option...Go to a salvage yard, or order a new thermostat housing (ETC6135) Thermostat Housing (Genuine Part # ETC6135) - Land Rover cooling/heating from Atlantic British WITH the threaded bung for the sensor. Then run the "straight hose" ESR3297

OMFG, who knew that such a logical part existed? Did this part come about AFTER the Classics ended their production and became backward-compatable?

No matter what the history is, THAT's what I need. Thanks, Pazzo Rover.

 

[pazzo rover]

That style therm housing showed up on the RRC in 1995. So now just add a new proper thermostat like...
Land Range Rover Discovery Freelander Defender Genuine OEM Factory Thermostat

Thermostat With Gasket - 190 Degrees F (Genuine Part # ETC4765) - Land Rover kits from Atlantic British

good luck

 

[brider]

So the factory DID recognize that top hose with the bonded-in sensor boss as a weak design!

 

[Funrover]

Yes, the coolant sensor (PRC3505) that lives in the Upper hose (ESR2167) controls the AC condenser fans. The sensor for the ECU is ETC8496 Sensor Temp (Ects) (Part # ETC8496) - Land Rover sending units from Atlantic British.

Probably wouldn't be my first choice to let the sensor hang. One option...Go to a salvage yard, or order a new thermostat housing (ETC6135) Thermostat Housing (Genuine Part # ETC6135) - Land Rover cooling/heating from Atlantic British WITH the threaded bung for the sensor. Then run the "straight hose" ESR3297

I think I may also do that, however I am currently doing the dreaded HG job.

 

[90 red rover]

is the HG jod dreaded for a specific reason or just because its lots of work and going somewhat deep into the motor? how much more work is it then the cam install? my rover just started to bubble out of the overflow tank cap on my last 4-wheeling trip. there was lots of very steep inclines to get to the top but it never showed too hot on the guage but at the top it was boiling over in the reservoir! seemed like overheating. maybe my cap is not letting the system get to pressure, thus the boiling?