Had a big service done a few hundred miles ago: new plugs, leads, fuel filter, air filter, oil and filter, rocker-cover gaskets; also had the coolant replaced.
Well, you know what they say about new coolant finding leaks and weak points... anyway the radiator developed a leak, at the edge of the rad (not the core), so I had to go ahead and have a complete new radiator fitted.
I'm not sure whether it was that the new radiator was made to different tollerances, or whether the hoses were simply past their best, but there was a weeping from the join between the "top"-hose and the rad that could be cured even by taking of the Mazda-fitted clip and using a much more substantial jubilee clip. So a new top hose was ordered and, after waiting a week to get one, fitted. Leaking now solved, it looked like I was back on the road again!
Two days ago I was sat in a nasty traffic jam - total gridlock! - trying to get out of town. The usual stop-go traffic, the temp gauge showing it's usual "just above half-way" reading, the fan kicking-in periodically to keep the temp down, when... "POP!"
Oh crap...
Steam gushes from under the bonnet (hood), and I pull over almost immediately. My car's entire supply of coolant now unhelpfully spread on the road, I open the bonnet (hood) expecting the worst...
I am then (pleasantly) suprised to see that the "bottom"-hose has come away from the radiator. So harmless enough, and no long-term damage done (I hope).
Here's my question (sorry for the long back-story): What could have caused this? Is it probable that the fit between the bottom-hose and the radiator is not perfect (all the hoses are almost certainly the originals (1993)), and a sturdier jubilee-clip and/or new hose would solve this problem? Or could it be that the mechanic did not bleed the cooling system properly?
I admit to not understanding how you would bleed the V6's cooling system, if indeed this is relevant or possible. I have previously worked on older-style cars, where you'd take the pressure-cap off the expansion tank and run the engine 'til warm, then loosen a bleed screw at the top of the radiator to let out any trapped air. Is this kind of procedure relevant to the K8? Also, what is the purpose of the two pressure-caps on the K8; one near the top of the inlet manifold, and one under the plastic intake manifold that runs along the top of the radiator?
Any advice appreciated!
Pete.
Radiator woes
Radiator woes
Stock '93 V6.
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Mnemonic
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how to bleed a v6 coolant system Very Easy but takes time:
with the car off and cooled go ahead and mix your 50/50 mix of water and coolant. when you have it filled to the top, go ahead and turn the car on, but leave the filler cap off now grab the upper and lower radiator hose and squeeze on them basically 1 after the other over and over and over. dont worry if you spill some coolant your going to be adding more and more as you do this. basically what your doing is getting all the air out of the system which is very important, so your going to keep doing this untill your coolant level stays at the top of the filler cap and you no longer see any bubbles coming up (took me about 20 mins to do this all).
also while your doing this, disconnect the fan so that it doesn't cut on, you want the motor to heat up to operation temperature so that the thermastat will open and flow more coolant through the system (you can leave the fan connected but it will cool the engine down and possibly keep the thermastat from opening fully). just make sure you keep an eye on your temp guage.
thats the best way i've found to bleed a coolant system.
Now as for your hoses constantly popping off, are you still using the crappy squeeze clip style fasteners? if you car go ahead and get you some of the screw style they will clamp tighter (its like a dollar for 2 so you'll spend like 2-3 dollars with taxes) if your still using the original coolant hose, just go ahead and replace it, its not much and really its part of regular maintence and will save you headache later on down the road. Now unless your original clamps are really old and just dont hold like they used to, they your hoses shouldn't just pop off. You might have an issue where the pressure is building up to much and the hoses just cant take it so since htere the weakest part of the system there not going to handle as much pressure, so you might have an issue with some blockage, not saying you do, its probably your pressure caps are old and just arnt opening and releasing the pressure like they should, there cheap as well so no point in cutting corners go ahead and get you a .6 pressure cap (easy to find at most auto parts store). if they dont open your pressure will just build and build and build until something goes.
If all that doesnt fix the issue, then your thermastat might not be opening up, this could also be a reason to why your engine is running slightly above mid way, living in atlanta ga in the US it gets between 32-37c here durring the summer and my engine stays right where the midway mark is on the fuel gauge. if your thermastat is going bad this will cause it not to open and that as well can increase pressure in the system (in theory the pressure should still be released from the pressure caps, but yet again if there old they might not be doing the job).
That should give you plenty of things to look at, its really not as much as it seems, your probably looking to spend 30-40usd to fix the issue, unless it is some type of blockage in the system.
To be honest, when your mechanic put in the radiator he should of checked all of this, not really sure why he didn't, not like it effects him in anyway except him making more money on labor from you. And personally i would just take care of it myself its easy to do and all you need is 10/12mm socket or wrench if you prefer, a flat head screw driver, a lil sand paper (incase thermastat housing has gunk on it) and some blue rtv sealent when resealing the thermastat housing.
hope that all helps
with the car off and cooled go ahead and mix your 50/50 mix of water and coolant. when you have it filled to the top, go ahead and turn the car on, but leave the filler cap off now grab the upper and lower radiator hose and squeeze on them basically 1 after the other over and over and over. dont worry if you spill some coolant your going to be adding more and more as you do this. basically what your doing is getting all the air out of the system which is very important, so your going to keep doing this untill your coolant level stays at the top of the filler cap and you no longer see any bubbles coming up (took me about 20 mins to do this all).
also while your doing this, disconnect the fan so that it doesn't cut on, you want the motor to heat up to operation temperature so that the thermastat will open and flow more coolant through the system (you can leave the fan connected but it will cool the engine down and possibly keep the thermastat from opening fully). just make sure you keep an eye on your temp guage.
thats the best way i've found to bleed a coolant system.
Now as for your hoses constantly popping off, are you still using the crappy squeeze clip style fasteners? if you car go ahead and get you some of the screw style they will clamp tighter (its like a dollar for 2 so you'll spend like 2-3 dollars with taxes) if your still using the original coolant hose, just go ahead and replace it, its not much and really its part of regular maintence and will save you headache later on down the road. Now unless your original clamps are really old and just dont hold like they used to, they your hoses shouldn't just pop off. You might have an issue where the pressure is building up to much and the hoses just cant take it so since htere the weakest part of the system there not going to handle as much pressure, so you might have an issue with some blockage, not saying you do, its probably your pressure caps are old and just arnt opening and releasing the pressure like they should, there cheap as well so no point in cutting corners go ahead and get you a .6 pressure cap (easy to find at most auto parts store). if they dont open your pressure will just build and build and build until something goes.
If all that doesnt fix the issue, then your thermastat might not be opening up, this could also be a reason to why your engine is running slightly above mid way, living in atlanta ga in the US it gets between 32-37c here durring the summer and my engine stays right where the midway mark is on the fuel gauge. if your thermastat is going bad this will cause it not to open and that as well can increase pressure in the system (in theory the pressure should still be released from the pressure caps, but yet again if there old they might not be doing the job).
That should give you plenty of things to look at, its really not as much as it seems, your probably looking to spend 30-40usd to fix the issue, unless it is some type of blockage in the system.
To be honest, when your mechanic put in the radiator he should of checked all of this, not really sure why he didn't, not like it effects him in anyway except him making more money on labor from you. And personally i would just take care of it myself its easy to do and all you need is 10/12mm socket or wrench if you prefer, a flat head screw driver, a lil sand paper (incase thermastat housing has gunk on it) and some blue rtv sealent when resealing the thermastat housing.
hope that all helps
08 Infiniti G37s 6speed (The Daily)
Stillen Cold Air Intake, Z1 Plenum Power Mod, Z1 Headers, Z1 Test Pipe, OBX (Ark) Exhaust, Up-Rev Osiris Engine Management (Tuned at Z1), 20x9" 20x10" Str Racing Concave Staggered Rims, SPC Camber kit, Tein H Techs Springs
01 Lexus Is300 (LS2 Project)
93 Mx3 SE 2.5 KLZE (sold it)
93 Mx3 GS 2.0 KFZE (killed it)
Stillen Cold Air Intake, Z1 Plenum Power Mod, Z1 Headers, Z1 Test Pipe, OBX (Ark) Exhaust, Up-Rev Osiris Engine Management (Tuned at Z1), 20x9" 20x10" Str Racing Concave Staggered Rims, SPC Camber kit, Tein H Techs Springs
01 Lexus Is300 (LS2 Project)
93 Mx3 SE 2.5 KLZE (sold it)
93 Mx3 GS 2.0 KFZE (killed it)
Let me try to answer the questions...
Crappy squeeze clips? Yes, they came with the car! The jubilee ones I mention are the screw-type you refer to.
Bad thermostat? Unlikely, as the radiator gets nice and hot.
Hot running? The "just above half-way" reading is one which has been the same since I got the car, and in that time I've had the coolant changed twice. Could be the sender, the gauge, or just the way my engine is! The important thing is that it never gets higher than that - the fan always kicks in.
Pressure caps One was replaced about 2 years ago (soon after I got the car), and the other I assume is original. Neither have ever "blown".
Does that narrow it down more?
Pete.
Crappy squeeze clips? Yes, they came with the car! The jubilee ones I mention are the screw-type you refer to.
Bad thermostat? Unlikely, as the radiator gets nice and hot.
Hot running? The "just above half-way" reading is one which has been the same since I got the car, and in that time I've had the coolant changed twice. Could be the sender, the gauge, or just the way my engine is! The important thing is that it never gets higher than that - the fan always kicks in.
Pressure caps One was replaced about 2 years ago (soon after I got the car), and the other I assume is original. Neither have ever "blown".
Does that narrow it down more?
Pete.
Stock '93 V6.