Coolant replacement

[NT400]

Haven't done it before , so any suggestions would be more tha helpful . As you know the 400 bros was an japanese import and therefor any work on the bike is done according to the hawkgt manual .I read the instructions and seem something easy to do . Just have some questions ...

1. The radiator cap can be removed by hand or do I have to find any special tool ???

2. The coolant fluid comes in two colours I think , blue and green . What's the diference , if there is one ???

3. How much fluid will I need to fill up the radiator and the reserve tank as well ??? 2 lt are enough ???

4. Do I really need to measure the radiator pressure ??

Since I will remove the the fuel tank I think it's a good chance to clean my K/N air box . I know it's washable but does it need any special equipment to wash or do I just take out the filter and put it in the sink ???

You may find these questions boring and silly , but I wouldn't like to pay for some thinks I can do on my own .Thanks in advance for any advice given

Spiros

[brewsy]

Hi Spiros.

The cap should come off by hand, just like on your car.

Coolant colour simply depends on the brand of antifreeze you buy. Make sure you mix it correctly as per the instructions, basically depends on the climate you live in. It can vary from 30:70 antifreeze:water to as much as 50:50 (or higher)

I think 2 litres should be enough to be sure check in the manual (online somewhere from the forum).

HTH,
Marc

[jaysun0ne]

the cap can be removed by hand just like any car. read the manual and it should tell you which bolt to remove from the water pump to drain the system. I never tested water pressure (I could be wrong but that's just to test if the pump is working correctly).

coolant can come in orange as well, I have never seen blue. what happen to the good old days when it was always green. im not sure of any difference, these different colored coolants just hit the market in the past few years and I haven't done any research on the subject.

the real trick is leaving the gas tank attached to the bike so you can turn it on and run all the air out of the system wile still having access to the coolant cap (located UNDER the front of the tank) so you can top it off wile the motor is on. that will insure most of the air is purged from the system. its simple.

[NT400]

Hi Spiros.

The cap should come off by hand, just like on your car.

Coolant colour simply depends on the brand of antifreeze you buy. Make sure you mix it correctly as per the instructions, basically depends on the climate you live in. It can vary from 30:70 antifreeze:water to as much as 50:50 (or higher)

I think 2 litres should be enough to be sure check in the manual (online somewhere from the forum).

HTH,
Marc

Thanks for the info . I wasn't intending to prepare a mix . I have a quantity of green antifreeze mixture at a percentage of 22 % ethylene glycol.Such a small rate is probably reasonable for the warm mediterranean greek climate .
But just in case I 'll try to get another mix richer in eth.glyc.

I think I 'll try it first thing saturday morning .

[jaysun0ne]

they sell it premixed 50/50

[PaullyBoy]

Just to clarify the difference in the colors of anti freeze is what it is made from, and if its animal friendly. Different car companys use different coolants to better suit the materials they use in their engines. I just used a 50/50 mix of the green in mine and it works fine.

[tkm433]

Re: Coolant replacement

Do not remove the radiator cap when the engine is hot!
The engine MUST be cool before you service the cooling system!
Use only distilled water and ethylene glycol in the cooling system.
Do not use alcohol-based antifreeze.
a 50-50 mixture is recommended for maximum corrosion protection.


First you are going to want to drain the system by removing the radiator cap first and then removing the lower bolt on the water pump cover. This bolt is the drain for the system.

After the system has drained replace the bolt in the water pump cover and beginn to fill at the radiator cap with the 50-50 miture of antifreeze and distilled water. Here in the USA we can buy it already premixed at most local auto supply store and even Honda sell it at the local motorcycle shop.

when yo fill the system let it sit for a minute or more to let any air in the system work its way to the top and you can squeeze the radiator hoses by hand a few times to help m ove any air out of the radiator. Once the water level is to to cap inatll the cap and check the over flow bottle for the correct amount of water for a cold engine.

Start the motor and check for any signs of leaks and if all is good take it for a short ride around the block to warm it up to tempature. Check the water level in the overflow bottle and correct if needed.

Dispose of any old antifreeze properly! Also clean up any spills and do not leave any antifreeze in an open container that aniamals or children could get to since the stuff will kill.

Coolant capacity: Coolant change: 1.60 lit
Total System: 2.20 lit

[LeftRightLeftThrottle]

What about flushing the system? Leave the drain hole open and stick a garden hose in the filler hole?

[NT400]

What about flushing the system? Leave the drain hole open and stick a garden hose in the filler hole?

That I would do I owned a garaze and had the time and space needed . But I' be doing the change of coolant on the pavement . Can't have the bike out of order too long. Big city living really sucks sometimes ...

[LeftRightLeftThrottle]

I know what you mean, I use my hawk to commute every day. This makes it really difficult to break down and get prepped for the track!

[HypnoToad]

I know what you mean, I use my hawk to commute every day.

Called the insurance company just yesterday and they said i could get another bros on the insurance for 25 euro extra.

Now I am looking out for a cheep new one
so i can work on one and use the other.

[NT400]

I know what you mean, I use my hawk to commute every day.

Called the insurance company just yesterday and they said i could get another bros on the insurance for 25 euro extra.

Now I am looking out for a cheep new one
so i can work on one and use the other.

Check the ad for the Repsoil Bros 650 . Looks in good condition but it's some in UK .

[GatorHawk]

Coolant Drain Bolt Torque Spec

Anyone know the torque spec for the drain bolt for the cooling system (near the water pump housing)?

It's not listed in the manual, and the standard spec for an M10 bolt seems kinda high for that little bolt.