Flushing Coolant From Block

[mad082]

if the thermostat isn't fully closed when you pull it out then it's stuffed. then put it in some boiling water. if it doesn't open all the way up then it is also stuffed. you can also tell whether it is stuffed of not by how long your car takes to warm up in the morning and where the needle sits when driving. the needle should sit about halfway on the gauge once up to temp, and should only take a few kms or a few mins of driving to come up to temp (longer if the car is just sitting idling)

[Galois]

hey guys,

so once you've flushed with tap water, how do you get the tap water out to add the pre-mixed stuff? it tends to be the suggested thing: grab 2x5L of nulon premixed LLC and replace the coolant, but how do you get the old water out?

Do you simply drain the radiator using the radiator drain plug down the bottom, then drain the engine using it's drain plug, then undo the top and bottom plugs for the heater to drain it?

If so: im guessing the heater has to be on?

AND where is the engine drain plug?

thanks guys

[Galois]

on the r34 is the thermostat by any chance connected to the bottom hose, not the top?

I couldn't see anything like 3 bolt fitting on the end of the radiator inlet pipe (to the radiator), but there was something like that completely inaccessible on the end of the radiator outlet pipe...

also, what does the 100/30 grade refer to?

thanks

Edited May 3, 2010 by Galois

[mad082]

i would assume that ther thermostat would be in the same place on the 34 as on the 33. maybe take a pic of what you are talking about. but on the 33, if you stand on the drivers side of the car and follow the top radiator hose from the radiator back towards the block, where it attaches to the block you should find the thermostat housing. it isn't attached to the radiator but to the engine block.

[central coast person]

any of use wouldnt happen to no where i can get the part labled 14875PA in the diagram below would you? Mine is busted and leaks coolant everywere.

Cheers

i can order it but its a 15 day wait from Nissan as a VOR

[central coast person]

Would probily do a radiator DIY on the weekend if you want too wait, there is a drain plug on the block i can locate easily. The RB26 has the exhaust front pipe blocking its one so the rb25 is VERY easy.

It work just as well as taking the thermostat out because your going to have to get a new gasket if you do that and the jobs going to take twice as long. All you need to do is put a hose in the top of the engine and let it flush out the drain hole on the block

[Galois]

cheers, looking forward to it mate. i did a flush last weekend with the worst method anyone's ever tried haha, took many many hours cos i used the water pump to push the water through. anyways, thanks man cant wait for the diy

[KrazyKong]

Would probily do a radiator DIY on the weekend if you want too wait, there is a drain plug on the block i can locate easily. The RB26 has the exhaust front pipe blocking its one so the rb25 is VERY easy.

It work just as well as taking the thermostat out because your going to have to get a new gasket if you do that and the jobs going to take twice as long. All you need to do is put a hose in the top of the engine and let it flush out the drain hole on the block

Yes please. Would love to see pics of the location of the drain plug and how to do a full flush efficiently. I'm due for one myself soon and would very much appreciate this.

[FloydWestwood]

me too.

[NISSAN GTR]

i used 10 x 4 litre bottles of demineralised water and flushed 7 times and still getting rusty block water coming out . owned

[KrazyKong]

Mark, I think it's ok to flush the system with tap water to get the water clean. Then, flush that out with new coolant. Though how to do what, well I'm not sure yet. I'm looking forward to Andrew posting some pics and a DIY on how to flush the radiator and water system properly.

[Galois]

yeah, you'd have to remove all the tap water first, but if you use de-ionised water you can just wait for it to be clear then add come concentrate to the radiator.

[KrazyKong]

Demineralised or de-ionised water? How much does this stuff cost?

You have a good point Galois. Would be easier to use that water, then go with some concentrate.

However I want to clean all the crap out of my system, and if the quickest and most effective way is to flush it with a hose, then I still like the sound of that. Once it's clear, then can proceed in draining it all. Then fill up with some coolant and drain a bit of that, top up and you're done. Seems simple, maybe too simple lol. Did I miss something?

[Galois]

either, i don't think there's any difference. when i was shopping for coolant is was about $6 for 4 litres, which is actually pretty cheap for water in a bottle lol.

still went with the nulon llc pre-mix, which was a mistake.

i thought mine was bad but it was actually ok. what i did, and i do not advise this, was open the radiator cap, connect the return-to-radiator pipe to a hose leading to a bucket, and started the engine. i used hot tap water (~80oC from kettle lol) and continually refilled the radiator. when the water became clear i started putting coolant in till it became fairly green. but there would still have been some tap water left over, so i went for a drive to mix all the fluid together, let it cool, and detached the bottom radiator pipe, draining ~4L as a guess from the pipe, partially from the engine cos of siphoning, and from the radiator. then i connected it all up and refilled with pre-mix. took all freaking afternoon.

i had planned to unplug the top and bottom engine draining plugs, same with radiator and heater, connect it all up and re-fill, but couldn't find the bottom plug on the engine. and i couldn't figure out how to get the thermostat out, so i couldn't just flush through the engine with the hose, so i used the water pump.

problems:

1. tap water may boil in the engine, causing damage to the radiator and other parts

2. so many burns lol

3. still tap water in there because it wasn't a proper flush. at least draining the radiator again dropped the concentration of tapwater contaminants

assuming the diy is similar to how u survived, or some other simple method, ill be doing it again soon. just to know that the best material is in the engine...

dont forget the thermostat has to be removed to get full water flow from the hose through the engine, since its closed at cold temps. which also means you need a silicon gasket for when you put it back in (apparently anyways)

[NISSAN GTR]

Mark, I think it's ok to flush the system with tap water to get the water clean. Then, flush that out with new coolant. Though how to do what, well I'm not sure yet. I'm looking forward to Andrew posting some pics and a DIY on how to flush the radiator and water system properly.

i just didnt want to use tap water at all because of Adelaide water , i think tap water will be hard to get rid of fully and will cause rust quicker than demineralised .

i was going to flush through the heater hose using a flush kit , but have you seen where the hoses are located , not possible

someone out there must know the best way .

[Wacky Dee]

a mate of mine whose missus is in the navy told me Adelaide is the only place in the world where docking ships NEVER fill up on water due to high calcium content or something like that. So yeah you did the smart thing by not putting that stuff in your engine.

[KrazyKong]

Wow interesting on the Adelaide tap water. I have tank water, so will be using that as it will be alot cleaner than tap water.

Still it makes you wonder what some mechanics do when you pay for a system flush. If it's that hard to get all the water out of the block and radiator, I bet most just drain the radiator, and fill er back up.

[central coast person]

Hey guys, i may not be doing it this weekend as the unfortunate events of last nights crash on the old pacific highway to two knows mates has left me in a position where i may stay away from constructive things on cars for a week or 2

[Galois]

thats cool mate. hope all's ok.

krazykong, yeah ive been wondering myself, its not likely every mechanic spends the time and effort required to properly flush the system then remove all the water, unless they use pumped demineralised water. it might not be too difficult if you knew where the drain plugs for the block are lol

[KrazyKong]

I did a few radiator flushes last week with some tank water and cheap coolant. Today I decided to look at it a bit deeper and was glad I did. My cooling system must be pharkn dirty as now I'm finding thus scum/past stuff under the radiator cap after driving it.

Was tricky for me getting to the thermostat. Finally did, but not after breaking a socket adapter since I was torquing it at the wrong angle. Good old $9 tool set ftw.

The end of where the top hose connects had corroded badly. There were jagged sections where it had rusted away. I hope the engine isn't this bad, but now way to check that . I'll have to file and sand the end down to make it even and try and get as much of the rusty crap off as possible.

Then looked at the bottom hose and inside was this mixture of black sludge, and rusty scummy crap. to the previous Jap owner! Though I should have had a look at this sooner I suppose. Compliance put new fluid in, but I can only guess they just drained the radiator itself and didn't look at anything else.

It was getting dark in the day, so I wasn't going to be able to finish this all off. Placed the hose into the top engine hole and left it on for about 10mins or so. Didn't have too much pressure, but it was alot more than just a trickle. Had the water flowing out the bottom hole.

I cleaned the rubber hoses a little, and have them soaking in some mild detergenty stuff for tonight. Also started filing off the corroded tip and crap from the thermostat housing. I know Kudos Motorsports sell a replacement, but the hoses sit so far up, the connection will still be good and safe once I have it all cleaned.

Other than that, I gave the radiator a few flushes with the tank water too.

I took the thermostat out, and originally was going to just get a replacement. But then realized it could very well be ok. So I put it in a pot of boiling water and it opened up just fine. I'm not sure if it's worth the $60 for a new Nissan one, or would an oem or no name one from one of the auto stores be just as good? I've replaced a few thermostats before in previous cars, but never had one as solidly built as the Nissan one I removed today. Also, there's the more expensive Nismo one too that opens up at a lower temperature. Most likely money not worth spending for my car as it's pretty much still stock.

I've got some gasket goo stuff too for when I put everything back together.

One question, how do I get water back into the engine once I install the thermostat. If I fill up the radiator, how will water get into the block if the thermostat is closed? Will it flow into the block via the return hose instead? Would like to know this before I turn the car on and mess something up. Also about whether people have gone with a genuine Nissan thermostat or an oem one.