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criten
P Plater
23 Posts
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 Posted - 10 Apr 2008 : 8:46:33 PM
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I'm a bit of a noob but trying to learn
I noticed the heater in the car takes a real long time to come on, and after cleaning the heater core etc. it still didn't improve. I should also note that if the car idles for 5 - 15 min (depending on if its a hot day or not) the engine will overheat. So I next thought of the thermostat...
The previous owner of the car tells me the thermostat is broken, its always open, and that its not worth fixing. Also says that with a working thermostat, the car overheats so there is some kind of cooling issue to address. I'm thinking the radiator, but I'm told a new one was installed about 5 years ago - but I'm certain this isn't true because its been damaged - looks much like I'd expect from when he jacked up the car from the bar just below the radiator (a big no no) about 10 years ago. Radiator has a crimp in the bottom, about 5cm deep that presses a bunch of the fins together. It also has many fins pressed together from where stones have hit it, and seems to be a matter of spotting an area that isn't damaged. It doesn't leak at all, but my previous experience in computers tells me that fin seperation with heat displacement devices is fairly important. Old owner also says that the thermostat hasn't worked for a fair while and by installing a new one I could possibly cause more problems by adding more heat and pressure, such as at the welch plugs and vacuum seal - or that the cooling issue itself may be an underlying issue with these.
Obviously from story about him screwing the radiator from jacking the car in the wrong spot, he isn't exactly a bright bloke. Is it worth trying to fix the thermostat? Is it true what the old owner said about damage by pressurization? Is there anything else I should be aware of if I try and fix this?
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jas89
Forum Moderator
779 Posts
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Posted - 11 Apr 2008 : 01:09:05 AM
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hey ..well really the car was desighned with a thermostat...its deffinally worth while to replace it...yes it will make the car run hottor but they are supposed to run pretty hot for good fuel econamy etc. Just replaced one in me mums vn today and it made heaps difference (temp guage acctually works now lol) it had a 82 derree one in it that looked sus....put a genuine one in that i think is a 91 degree one, got it from holden for 7.50
as for the over heating well id say one and maybe the whole problem is indeed the radiator it shouldnt have more then (i think its) 2 chambers blocked off otherwise over heating issues could result
however does the thermo fan cut in when it overheats?? and you say overheat....is that meaning reaching red on the guage? also you say the thermostat is faulty....definally replace as neither know you say its stuck open it may be sticking closed at some stage while idleing etc causeing the overheating issue
and yeh it will preassure the system a bit but there a pressurised cooling system...aagaing its desighned this way.
good luck |
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trizo
Forum Moderator
3091 Posts
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Posted - 11 Apr 2008 : 05:19:54 AM
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if your rad is squashedup like you say , I"d be replacing it, not hard its a 2min job, the thermostst can be a tricky 1 depending on the series of you engine if its a s2 you safe as houses and its a easy job, but if its a s1 be prepared for yellin and screaming cause there a mother focker to get out, for the reason they sit below the t/b on the s1 and have a nasty habit of siezing up.. but always good to replace broken things, try doing a forward and reverse flush on the rad first, if the thermo is stuk open it would not over heat/ stuk closed yes ! make sure all heater hoses ect are unbloked as they fill up with gunk over time , there are a few more things but its 3am and cant think  let us know how you go! |
3 can keep a secret if 2 are dead |
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criten
P Plater
23 Posts
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Posted - 12 Apr 2008 : 12:32:37 AM
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I tend to agree - if its on there by design, its probably there for a reason
Fuel economy is where it sits I believe... this evening I did 130km, but I had pre-warmed the engine. Having the heater on seems to warm it quicker. Did the same trip last week, this time I used HALF as much petrol - 2/8's last time, 1/8 this time. Can't really be due to traffic, there was none both times
Had a nice chatty last night with VNSVLE (I think?) - he suggested the cooling issue could be an air pocket and I should try bleeding it - convinced dad to show me how to do it on the weekend.
Will have to check for bubbles with radiator cap off. I'm also told a hose in the radiator with your thumb over the end, you should feel it suck down to indicate flow. Will flush it, bleed it, and if that fails, begin pulling apart the coolant lines checking for blocks.
I have a series 1, thermo fan cuts in, and when I say it overheats I mean water begins to gush from the radiator cap even though its firmly fitted. This usually is red on the guage, but not always.
It hasn't actually cooked while I've had it, but I do know this cars history (known the old owner for ages). Had all kinds of overheating problems about 8-10 years ago, apparently the fix was to jimmy the thermostat. What does concern me is sitting in peak hour traffic, the car has come very close to cooking itself while I've had it and the traffic wasn't really all that bad for peak hour |
Edited by - criten on 12 Apr 2008 12:38:30 AM |
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trizo
Forum Moderator
3091 Posts
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Posted - 12 Apr 2008 : 10:36:46 AM
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| hmmm steve chatting? Its a mtter of trial and error m8 go through probable causes and then work from there , plus you get to learn more about your car!! |
3 can keep a secret if 2 are dead |
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jas89
Forum Moderator
779 Posts
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Posted - 12 Apr 2008 : 1:17:21 PM
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hmm sounds badish....but could most probly be an easy fix
i know my vn had gone all the way to H a few times...found out me coolent temp sensor (and thermostat) was rooted makeing the fan not cut in but seeing that you said it does then thats out of the question.
when was the water pump changed last (if you know and if it has been?) as its possiable that the fins have corroded off the impellar in the pump resulting in poor coolent circulation. water pumps about 60-80 (gasket 5 bucks if not included with pump) for a decent one.
as for the coolent pouring out from the cap, does the surge tank loo ok as in is there any cracks in the tank around the cap and well anywhere on the tank.
hope it helps |
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criten
P Plater
23 Posts
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Posted - 12 Apr 2008 : 2:01:15 PM
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Heh, I noticed there is a crack in the coolant surge tank that has been repaired. Also noticed in the holden manuals it makes a bit of a deal about how this isn't a repairable part in any way. Might have to swap that over one day, but the said repair seems to be airtight.
But no, there isn't anything that it'd leak from. The cap itself under high pressure will release some of the pressure, by design. But yer, hasn't actually done this for a few years but I have seen it happen on that car before I owned it |
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criten
P Plater
23 Posts
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Posted - 12 Apr 2008 : 4:38:13 PM
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| My water pump is leaking around one of the seals... whats the best route at getting a replacement? New or wreckers? Or can I repair this? |
Edited by - criten on 12 Apr 2008 4:40:12 PM |
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jas89
Forum Moderator
779 Posts
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Posted - 12 Apr 2008 : 7:41:23 PM
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if its leaking in any way id definally replace it.if you can take the belt of (noteing the correct way it came off) and spin the water pumnp by hand ...it should be smooth, if it rough or noisy replace
me personally id go with a new one as its the main part the pumps coolent/water around your engin.. |
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criten
P Plater
23 Posts
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Posted - 12 Apr 2008 : 10:40:00 PM
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I identified some the lines I've found to be leaking - they are:
engine to water valve hose (deteriorating)
water valve to engine hose (leak + badly deteriorated at end)
oil cooler lines (upper is leaking, lower is deteriorating)
radiator outlet hose (leak + deteriorated at end + already very short)
All being related to cooling, it can't help... I'll have to replace those asap, as well as the water pump |
Edited by - criten on 12 Apr 2008 10:41:59 PM |
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jas89
Forum Moderator
779 Posts
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Posted - 12 Apr 2008 : 11:32:08 PM
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| good luck and let us know how it all goes |
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criten
P Plater
23 Posts
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Posted - 24 Apr 2008 : 9:38:53 PM
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damnit, my hoses still ain't turned up... been ages
I'll have to make angry phonecalls later |
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trizo
Forum Moderator
3091 Posts
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Posted - 24 Apr 2008 : 9:43:43 PM
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| buy direct dude .. coventrys or somthing!! when you fit all you hoses make sure you froward and reverse flush! if you can get a compessor in there! |
3 can keep a secret if 2 are dead |
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criten
P Plater
23 Posts
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Posted - 25 Apr 2008 : 12:37:51 AM
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compressed water fed through the engine? hmmmm... I wonder if... my grandfather a few months ago gave me his compressor and a big box of bits for it
I'll have to dig around and see if I got the stuff, but thats probably not a bad idea
what kind of psi is safe?
or better yet, what kind of psi can the engine tolerate? I imagine there is some large degree of variation with this, as the coolant heats up and cools |
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trizo
Forum Moderator
3091 Posts
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Posted - 25 Apr 2008 : 1:09:32 PM
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| just enough to force the gunk out! |
3 can keep a secret if 2 are dead |
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Aussie Infidel
Starting in the driveway
3 Posts
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Posted - 21 Jul 2008 : 7:13:07 PM
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| hey i had heaps of probs with cooling on a vx i had and it turned out to be the radiator cap, something we never think of |
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jas89
Forum Moderator
779 Posts
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Posted - 21 Jul 2008 : 8:44:09 PM
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3 month old post
but true, the radiator caps can cause this, as when i replaced teh cap on me vs the other day, the temp stays cooler now |
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trizo
Forum Moderator
3091 Posts
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Posted - 21 Jul 2008 : 11:56:49 PM
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| kaaaaaaaching thanx jassy boy locked! |
3 can keep a secret if 2 are dead |
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