Took my 01 Vdp for a test drive today to the car wash, I pulled back into my driveway and it wasn't until after I turn the car off and it was a couple minutes before the hose from the thermostat to the passenger side of the radiator blew off. Immediately I think, thermostat, because this is exactly what happened to my xj sport. So I took the thermostat off and tested it in boiling water, and it opened. So the thermostat is good still. Idk if I just didn't have the screw clamp tight enough or something in the radiator is clogged. But I'm going to try and do a flush with irontite Thoro flush, before I do though, is there any advice anyone can give me? Things to check? Background info. Heads just rebuilt and the coolant passage ways were all cleaned out of any gunk. But as for the rest of the coolant system, the previous owner used some coolant sealant and that's why I'm going to flush it.

 

That sealant crap can mess up a radiator, amongst other cooling/heating system parts. Since you've had the heads done, I'd seriously consider pulling the radiator and having a shop boil it out and pressure it. That's a win/win regarding surety and peace of mind. I just hope that seal stuff didn't mess with your heater core.

 

If one of the fans stopped working, could this cause a hose to blow?

 

There have been many incidences of the hoses coming off due to degradation of the plastic crossover pipe.

 

+1 to RJ237 and to answer your question yes, though doubtful, but your gauge should had shown it was hot, if you were looking there that is.

 

+2. If you are using the screw type clamp, you need to check it more often than you check the oil. Especially in cold weather.

Lots of threads.

Mine blew in zero degree weather; took the opportunity to replace everything, including TST tower, TST (again), water pump (again) and the offending crossover pipe (shocked to see how badly it had deteriorated, inside out). And all hoses and clamps. Elsewhere, Bob Goff has suggested using spring clamps instead of screw-types since they adjust to cold.

 

I flushed the system good and made sure the clamps were tight, but not too tight and it hasn't blow any hoses yet, I have been driving it the past 2 days, about 20 miles in one drive, I also checked the temperature of all the hoses and the thermostat, and they are looking around 195-205. The 2 hoses that go from the radiator to the thermostat are reading both the same at 197.


However I noticed something off topic this morning when I cold started it, it has a squeaky noise coming from the serpentine belt, before I put the belt on I inspected it and it looked brand new, could spraying WD40 on the bearings of the water pump or any of the other pulleys fix this squeak?

 

It may be a pulley failing. The idler and tensioner can usually be checked by removing the belt and seeing if they spin freely. WD40 is not a fix, replacement is.

 

+1 to RJ237 again, remove the belt and check the pulleys for play and as stated WD40 is not a fix, its not even a lubricant, its a Water Displacement formula.
If its a fixed pulley, the bearing is very easy and cheap to change...

 

+2 I had to replace my tensioner: the bolt literally crumbled as I tried to loosen it to remove the belt for my first water pump change. as a 2001, your car is 16 years old!

 

I am having the same problem with the hose blowing off. I am installing a new metal housing and am going to have a compression test and flush the cooling system. I hope this takes care of the problem. The main thing that concerns is a possible head gasket leak. Thanks for your post, I posted the same problem also. If you find the cause please post. (Thanks Dave)