Guinness
|
| posted on 18/8/09 at 02:56 PM |
|
|
Totally fed up now!!
I'm totally fed up now.
I've run the ZZR engine in the Indy since it passed it's SVA in Nov 05. So that's nearly 4 years with the same cooling set up.
At some point over the winter it developed a problem in the cooling system. First few runs out this year it took an age to warm up (which I put down
to very low ambient temps) and then just wouldn't cool down. I thought I had some oil in the coolant, very slight traces of mayo in the filler
cap.
I stuck some K-seal in there as I didn't want to miss out any driving time. This blocked the overflow from the expansion cap to the expansion
bottle 
Since then I did a trackday, the FBB09 round Scotland and several other big days out. On the last day of the FBB09 in Edinburgh it got a pinhole
split in one of the coolant hoses. Which resulted in a jet of hot coolant shooting about 10' across the car park and lots of steam!
Replaced the hose with new silicone and topped up, bled the system again etc.
Each time I had the same symptom, took a while to warm up, then just wouldn't cool down again. Top up the coolant in the morning, drive for a
while, then when it cooled, check the coolant again, and about 100ml was missing! The expansion bottle stays at the same level?
The cooling system is as it is in the bike, apart from a slightly bigger radiator. So it goes head > thermostat > expansion cap (with overflow
to expansion bottle) > radiator > pipe > water pump > block > head > etc etc.
I've drained it, bled it, flushed it through, changed the water pump, checked the water pump works, bled it. I get hot water in all the pipes /
elements of the cooling system in the right order.
I've just stripped the engine down, replaced the head gasket, skimmed the head and put it all back together and I get the same symptoms.
Fill the system up, run the engine, stop the engine, take the filler cap off, 100ml of water gone.
Thing is, the engine still runs and seems to put out very decent amounts of power. I've no problem keeping up with the lads in 2.0 zetecs
etc.
I've run copious quantities of water through the system as a whole (from filler cap to drain) and through all the parts individually so there
are no blockages / airlocks.
What do I do?
Seriously tempted to rip the Zed out and go CEC! 
Mike
|
|
|
|
|
philtvr
|
| posted on 18/8/09 at 03:07 PM |
|
|
2 thoughts are
Thermostat - faulty not opening at right temp hence slow warm up.
Header tank cap seal gone - allows steam out (water loss) + system cant pressurize???
|
|
|
Guinness
|
| posted on 18/8/09 at 03:27 PM |
|
|
Thermostat checked in hot water, opens OK. Swapped with a spare - already checked. Opens OK.
Header cap swapped with another one. No difference.
The drop in water level is rapid. With the engine warm, top it up to "full". Leave the cap off, come in, write this long tale of woe, go
outside need to top up the water by 100ml.
It's not going on the floor of the garage, it isn't going into the block (oil level stays the same and isn't emulsified).
???????
Mike
|
|
|
philtvr
|
| posted on 18/8/09 at 03:29 PM |
|
|
water fairies?
|
|
|
02GF74
|
| posted on 18/8/09 at 03:31 PM |
|
|
quote:
Originally posted by Guinness
At some point over the winter it developed a problem in the cooling system. First few runs out this year it took an age to warm up (which I put down
to very low ambient temps) and then just wouldn't cool down.
Stating the obvious, is the thermostat fitted, fitted correct way and known ot be working? Have you run it without the thermostat to see
what difference it makes? Weird symptoms as it sounds like the 'stat is open sthus taking ages to get up to temp - are you driving it at the
time or stationary? Is the cooling fan running during this time? And then not cooling down sounds like the thermostat is closed; again does fan kick
in?
I stuck some K-seal in there as I didn't want to miss out any driving time. This blocked the overflow from the expansion cap to the expansion
bottle
That and radweld comes out of satan's own arse - a bodge - who knows what else is blocked up, did you check waterways in block and
hoses when rebuilding?
some things to try and report back.
car stationary in garage - start engine and let run, observe water temp guage every 5 minutes or more and record time engine is up to temp (do you
trust the gauge to be corect?)
also feel hose to rad - it should be mostly cold but will get hotter when the thermostat opens/
keep engine running and watch gauge - does the fan kick in? does the temperaturee drop - is that shown on the guage? goes fan stop running? is fan
blowing/sucking air in right direction according to where it is mounted.
ideally you want to measure the temp independent of the guage - maplins are doing the digital thermometer at special price.
|
|
|
02GF74
|
| posted on 18/8/09 at 03:34 PM |
|
|
quote:
Originally posted by Guinness
The drop in water level is rapid. With the engine warm, top it up to "full". Leave the cap off, come in, write this long tale of woe, go
outside need to top up the water by 100ml.
It's not going on the floor of the garage, it isn't going into the block (oil level stays the same and isn't emulsified).
explain - water will expand when hot and contract when cold.
if you repeat the start/stop process with cap on, do you need to top up water every time? if so, it is leaving the engine one way or the other.
100 ml is 1/3 of a coke tin - how long does the enigne run for that to disappear?
what do spark plugs look like - will be very clean if the water is lost via engine aka steam cleaning.
[Edited on 18/8/09 by 02GF74]
|
|
|
Coose
|
| posted on 18/8/09 at 03:34 PM |
|
|
That's a strange one old chap, and difficult to diagnose without looking at it. I take it that you've replaced the stat and flushed the
radiator (though neither of these really give the symptoms that you are suggesting)? Are you sure that the temperature gauge is ok? The loss of water
is head-scratching if it's not appearing in the header tank, which I assume is vented to atmosphere? Is the water inlet on the header tank at
the bottom, or does it have a tube running to the bottom of the tank if the inlet is at the top? The cooling system should effectively find its level,
pushing out a bit of water into the tank when it warms up, then drawing it back again once it cools.
Spin 'er off Well...
|
|
|
Coose
|
| posted on 18/8/09 at 03:38 PM |
|
|
Ooooh, lots of posts since I started typing my reply, which has been pretty-much answered!
Just one thought - the thermostat should have a little hole in the flange that should be at the top should the stat be laid on its side. Is this the
case or have you fitted it with the hole at the bottom? If so, you'll have a chunk of trapped air in there that will expand more than the water
when hot.....
Spin 'er off Well...
|
|
|
Guinness
|
| posted on 18/8/09 at 03:59 PM |
|
|
Thermostat is OK. Installed the right way round with the hole at the top.
Start the engine, temp gauge climbs, thermostat housing gets hot. Then thermostat opens water flows along top pipe into rad. Rad heats up from top
to bottom. After about 5 mins, rad is fully hot, bottom pipes / hoses get hot.
I know water expands when hot and contracts when cool, but not as much as I am seeing! (although I have struggled to find a % increase for a given
volume / temperature increase!).
There is a bleed valve on the hot side of the thermostat, which is where the air seems to be.
i.e. the water level drop is about the same as from the top of the thermostat housing down to the hole in the thermostat! ?
I've just been out and taken all the hoses / pipework off the car and run the hose pipe through them. No blockages at all.
Mike
|
|
|
pewe
|
| posted on 18/8/09 at 04:47 PM |
|
|
Just to add a curved ball thought - water pump impeller moving on the shaft when hot?
Cheers, Pewe 
|
|
|
Guinness
|
| posted on 18/8/09 at 04:50 PM |
|
|
quote:
Originally posted by pewe
Just to add a curved ball thought - water pump impeller moving on the shaft when hot?
Cheers, Pewe
Replaced water pump with another known good one!
Water pump observed spinning when engine turned over (before hoses connected up to it!).
Thanks though 
Mike
|
|
|
t16turbotone
|
| posted on 18/8/09 at 05:04 PM |
|
|
done a 'sniffer' test?
|
|
|
Guinness
|
| posted on 18/8/09 at 05:07 PM |
|
|
quote:
Originally posted by t16turbotone
done a 'sniffer' test?
?? For exhaust gases in the coolant - no, but I have just had the head skimmed and replaced the head gasket.
Mike
|
|
|
pgtips
|
| posted on 18/8/09 at 05:41 PM |
|
|
quote:
Originally posted by Guinness
quote:
Originally posted by t16turbotone
done a 'sniffer' test?
?? For exhaust gases in the coolant - no, but I have just had the head skimmed and replaced the head gasket.
Mike
Have they pressure test the c/head when they had it in for the skimm job? The head maybe cracked? The engine block maybe cracked? Have you checked the
radiator for any blockages?
Very strange fault fella but very diffcult to diag with out been there. If you can do a sniff test I will do that next......seems you have tried
everything else. You could have a massive air lock someore on the cooland system. On some cars in the workshop they are so bad with airlocks that we
have to jack up the front or the back of the vehicle (depends the model) so we can get rid of the air locks.
Is there a bleed screw anywhere in the engine? If it is you will need to undo all bleeding screws and fill the system up till cooland poors out of
them.........but I am sure that's the way you are doing it anyway.
Good luck I am sure you will find the fault soon.
[Edited on 18/8/09 by pgtips]
If I die, my biggest fear is that my wife sells all my toys for the price I told her I bought them for...
|
|
|
Guinness
|
| posted on 18/8/09 at 06:34 PM |
|
|
They didn't pressure test the head. I'm thinking they should have now!
The design of the big zed seems to avoid mixing water and oil. The oil is fed to the head via an external rubber hose. The excess / used oil flows
back down the cam chain, avoiding all the cylinders completely.
The water jacket comes in the cylinder block, goes past the cylinders and into the underside of the head. From the underside of the head it comes
straight out the side, well below the level of the cams in the head.
I guess it is possible there is a crack in the head or block.
Mike
|
|
|
dmac
|
| posted on 18/8/09 at 07:44 PM |
|
|
Is it constantly losing water or is it just settling at a level it is happy with?
If you fill it when cold, run it up to temperature and then let it cool (so that it loses its 100ml) then once it is cool, run it up to temperature
again does it lose another 100ml or does the level stay the same?
Some installations just seem to gather air in certain places, it could be due the the levels of the radiator and header tank being different from
those of the original bike in comparison to the engine.
Duncan
|
|
|
Guinness
|
| posted on 18/8/09 at 07:53 PM |
|
|
quote:
Originally posted by dmac
Is it constantly losing water or is it just settling at a level it is happy with?
If you fill it when cold, run it up to temperature and then let it cool (so that it loses its 100ml) then once it is cool, run it up to temperature
again does it lose another 100ml or does the level stay the same?
Some installations just seem to gather air in certain places, it could be due the the levels of the radiator and header tank being different from
those of the original bike in comparison to the engine.
Duncan
What seems to happen is, if you imagine two pipes running vertically alongside one another with the themostat on top forming an arch, or inverted U
shape, then the level of the coolant drops to just below the level of the U. This means the temp sender is sitting in hot air, rather than coolant,
and the level falls so far that the thermostat cools and closes, which stops the coolant pumping round.
??
Mike
[Edited on 18/8/09 by Guinness]
|
|
|
Regsmonster
|
| posted on 18/8/09 at 07:54 PM |
|
|
I assume you're bleeding the pump as well as the thermostat housing?
|
|
|
pgtips
|
| posted on 18/8/09 at 07:59 PM |
|
|
It sounds like an airlock Mike.
Can you some how force fill the coolant system? I know Snap on used/still sells a coolant fill system because of the same thing.......air on the
system.
[Edited on 18/8/09 by pgtips]
If I die, my biggest fear is that my wife sells all my toys for the price I told her I bought them for...
|
|
|
dmac
|
| posted on 18/8/09 at 08:00 PM |
|
|
Its been a while since I saw a zzr engine and I can't remember what the thermostat looks like but it seems a strange arrangement to have it in
an air trap like that, if there is a bleed connection on it, try connecting that to your header tank to allow it to automatically bleed.
Duncan
|
|
|
s2gse
|
| posted on 18/8/09 at 09:15 PM |
|
|
not sure if this helps but i had a problem with levels going up and down on my GSXR1000 engine i had moved the header tank to a new position at the
front after 5 hrs of refilling a number of times
i found the problem was the distance between the top of the radiator and the header tank was to close i moved the radiator down alittle so the top of
the radiator is level with the min line on the header tank
when the temp gets to 90 degrees the water expands to the max line then when the engine is switched off and cools down goes back to the min line
life's to short and so was the drive
|
|
|
02GF74
|
| posted on 18/8/09 at 09:16 PM |
|
|
I'm not quite getting the water level thing - is the level dropping just when engine has warmed and then returns to previous level when cold or
not? If not, then it is losing water somehow i.e. you have to keep topping the water up.
The former would indicate an air lock situation, probably.
|
|
|
Guinness
|
| posted on 18/8/09 at 09:41 PM |
|
|
quote:
Originally posted by 02GF74
I'm not quite getting the water level thing - is the level dropping just when engine has warmed and then returns to previous level when cold or
not? If not, then it is losing water somehow i.e. you have to keep topping the water up.
The former would indicate an air lock situation, probably.
Sorry if it's getting confusing. I start the session with the engine and coolant cold and filled to the top of the thermostat and all air bled
out (as far as I can tell).
Start the engine and the level rises slightly as it warms up. Say 5mm in a 25mm wide tube?
Then switch the engine off, go inside have a cup of coffee, go back outside the water level has dropped to below the level of the thermostat exposing
it. I add another 100ml of water and start the engine again. Run it for 10 mins, stop. Let it cool down, it drops again.
I can do this 5 times before I get really bored! So I've added about half a litre to the 3.5 litres it takes to fill the system from empty?
If I leave it cold tonight, top it up full, leave the cap off, by the time I get up in the morning it'll have dropped again.
It could be an air lock, but I've filled and bled the system with the car flat in the garage, with the nose up on axle stands, and with the car
with two wheels up on the kerb.
That much water must be getting into a cylinder and being steamed off. But what I don't get is with the carbs off and the exhaust manifold off,
I don't get any water in the exhaust ports when I turn it over?
Mike
|
|
|
:{THC}:YosamiteSam
|
| posted on 19/8/09 at 03:00 AM |
|
|
i would do a compression check mike
|
|
|
t16turbotone
|
| posted on 19/8/09 at 06:53 AM |
|
|
from what i can understand It seems to me that water only drops to a particular level?- which would suggest to me that you have a problem in the top
half of the engine i.e cylinder head....do a sniffer and compression test mate
|
|
|
