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Q's about flushing cooling system (I know this has been posted alot but...)

tsimira

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I have been trying to get my head around every step before I do it, but from the previous threads I have searched and read through, I am confused on some of the points as there seem to be a million different ways to do it. :confused:

If I put down the steps as I can best understand them (collated from previous threads), could someone clear up or correct me on the areas I have got wrong. I am planning on running some cleaner in addition to flushing it completely.


Steps..

1. Set heater to hot & pour contents of cleaner into radiator and run engine for 20-30mins and then let cool.

2. Undo top & bottom hoses from radiator and let it drain out, then put a hose in the bottom hole (of radiator) and flush it up and out with water.

(now this is where I really start to get confused)

Do I...

3a. Remove the thermostat & housing then stick the hose in there and flush it with water. Q: where would the water come out, and is the engine running or not?

or

3b. Remove the top & bottom hoses from the engine and flush water through the top hole (and I'm guessing would then come out the bottom hole? and same again, engine running or not?)

or

3c. Re-attatch both hoses to radiator & undo heater hose, take off radiator cap and stick the hose in there and flush it that way (I'm guessing water would come out of the hole the heater hose was attatched to?; would that clean the entire engine?)



In order for the engine side of the clean/flush to be cleaned properly, is that (whichever of those steps) all that would need to be done? I am confused about this whole thing about the block holding something like 3 litres. Now will that 3 litres have been cleaned if the whole system was being flushed with water (flushing the crap out and leaving just clean water)? Or does it need to be drained seperately from the third step?


If the coolant is a 50/50 mix, then would those 3lt make up part of the 50% water side of the mix?


For a VN (V6 if its relevant) how much coolant/water can I expect it would hold in total? A guy at the store I bought the coolant from said 8lt total, so to pour 4lt of coolant in and top up with water. Is that correct or not? Also where should I actually pour the coolant into? On the boards I have read to either pour it directly into the radiator or directly into the top hose on the engine, so which one would it be?


If one of the options for step 3 is correct and thats all I need to do for the cleaning, would I now just pour in the coolant (however much I would need to make 50/50 mix) and then top it up with water until its full?


I do know that at some point at the end I will have to bleed the air out of the system, its just the steps beforehand I am confused about. With so many different points of view on the board I dont know which one to go with! I know its I'm a pain in the arse as it has been brought up a lot, but I do need to ask for me to get my head around it properly before I am actually confident to do it myself, and I know you guys know are a lot more knowledgeable than me!

Any help would be wonderful! Thanks muchly, I do hope one day I will be able to return the favor.

tsimira :)
 

maginoodle

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Hi, i can help a little bit
3a- do it this way, motor off. the water will come out of the bottom radiater hose.
3b-dont do this. if you did it this way the thermostat will stop water from getting in.
3c-leave the thermo stat and top radiater hose off. not sure how the hoses run on vn. i would undo both hoses to the heater and flush out with water.Put the heater hoses on.
Now you have the engine and heater cean you should be good to top back up.
I put my coolant in slowly so that when iut starts to come up to the thermostat level i can see it. Once i can see it, i put the thermostat baqck in and put the top hose back on.
I then start the motor and put the remaining coolant in.
If you put the coolant in slowly the engine should get to operating temp and the thermostat should open and the air will self bleed.
The manual says they take 10 L of water so put 5L of coolant in first then top up with water.
Hope you can understand what i've said. I am rushing this before work. Cheers
 

VNPOWER

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Oh god. such an easy job made soo hard!
THere are many ways to do this, this is how i do mine.. done it on my mums VN too. Never had a problem.
Ok

Step 1: Turn your Engine off. Make sure the car has cooled for at least 30minutes or suffer hot coolant on your hands :p

Step 2: Take the Top and bottom hose off, the water will come out.

Step 3: Stick your garden hose in the top of the radiator where you took the top hose off. Flush the radiator out. The water will flow out the bottom.

Step 4: Stick the garden hose in the top hose, and the water will either flow through the whole system and come out the bottom hose, or it will come back at you due to the thermostat. If it comes back at you, its a good sign, your thermostat is closed like it should be.

Step 5: Now once you have flushed out the system, simply put the top and bottom hose back on and fill the radiator up with new coolant. I asually get about 5L in it, then a little more but i just put water.

Step 6: Once its all put back on, leave the radiator cap off, or the cap on your surge tank, and start the car. Let it idle for 5-10minutes to the thermostat opens and you will notice once it opens, the water will flow down and you will have to add more coolant. Do this to its full, then simply put the cap back on and you are done for now.

Step 7: Next day: Once you have used your car for a bit, wait till its cooled down and check the level in your radiator, if there is more room for coolant. top it up some more.


You might even have a little screw near the thermostat, since you have a series 2 engine. You can use this to bleed the air out of the system.

Hope this helps
 

maginoodle

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kinkbike_rider said:
Would this be basically the same process for a VT, any changes?
pretty much the same for all cars except volkswagons (they are air cooled)
 
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tsimira

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maginoodle said:
Hi, i can help a little bit
3a- do it this way, motor off. the water will come out of the bottom radiater hose.
3b-dont do this. if you did it this way the thermostat will stop water from getting in.
3c-leave the thermo stat and top radiater hose off. not sure how the hoses run on vn. i would undo both hoses to the heater and flush out with water.Put the heater hoses on.
Now you have the engine and heater cean you should be good to top back up.
I put my coolant in slowly so that when iut starts to come up to the thermostat level i can see it. Once i can see it, i put the thermostat baqck in and put the top hose back on.
I then start the motor and put the remaining coolant in.
If you put the coolant in slowly the engine should get to operating temp and the thermostat should open and the air will self bleed.
The manual says they take 10 L of water so put 5L of coolant in first then top up with water.
Hope you can understand what i've said. I am rushing this before work. Cheers
Thanks for the reply, it didnt even occur to me to look at the manual re: capacity, just looked in mine and it says 10lt too. Just a couple of further questions, 3b is obviously not the way to go, but would I have to do both 3a & 3c, or will just doing 3a clean out the heater aswell? Also, do you put your coolant into the radiator or directly into the engine? (and if the latter, in where do you pour it?)

VNPOWER said:
Oh god. such an easy job made soo hard!
THere are many ways to do this, this is how i do mine.. done it on my mums VN too. Never had a problem.
Ok

*snip*
Step 4: Stick the garden hose in the top hose, and the water will either flow through the whole system and come out the bottom hose, or it will come back at you due to the thermostat. If it comes back at you, its a good sign, your thermostat is closed like it should be.
*snip*
Thanks for your reply also. Its not that I think its a hard job exactly, I just like to know exactly what I am doing with each step, and what is going on when I do it. With things I have no experience with I dont like to make any assumptions incase I bugger it up royally, and because what I have read differs so much I had to ask! Its like they say, its always easy once you know how ;) lol

One question for you though, if I flushed it through the top hose and the thermostat is closed so the water comes back at me, does that mean the water hasnt circulated throughout the entire system? Would removing the thermostat stop that being a problem?

Once again thankyou both for your help!

tsimira :)
 

VNPOWER

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tsimira said:
One question for you though, if I flushed it through the top hose and the thermostat is closed so the water comes back at me, does that mean the water hasnt circulated throughout the entire system? Would removing the thermostat stop that being a problem?

tsimira :)

If its splashes back at you, dont worry about it. I wouldnt bother taking the thermostat out, too much work for nothing. Dont worry about flushing out the system.
 

tsimira

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VNPOWER said:
If its splashes back at you, dont worry about it. I wouldnt bother taking the thermostat out, too much work for nothing. Dont worry about flushing out the system.
err??

It really does need to be cleaned as I dont think the guy who gave me the car had done it for a long time so whatever is running through the system looks pretty bad. I just want to be sure of what I am doing beforehand, I dont wanna be like almost every guy I know; winging it and then realising halfway through they have no idea what they are doing lol ;) :p

tsimira :)
 

sircruisealotVS

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something to keep in mind....DONT, release coolant from a warm engine, unless you want to crack your block.
leave it for at least a few hours before you flush the system, the sudden temperature change can crack the engine block otherwise.
 

maginoodle

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Hi, I am not to sure what series vn yours is. Series 1 has the thermostat at the back of the motor.I would leave them on and just flush the radiater and heater.
I would then fill the radiater up with water only, then go for a drive to get the thermostat open. Then re-flush everything and then top up with coolant and water.
If yours is a series 2 i the thermostat is at the front of the motor. I would remove the thermostat and flush the motor out and the heater. I would then put the heater hoses back on and the bottom radiater hose. Then put the coolant into the radiater, watching the level at the thermostat hole. When it gets near the top of the thermostat hole, put the thermostat back in and put the top radiater hose on. Then top up coolant.
 
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