Losing water .......OMG Its Hot

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chrisd2211

Losing water .......OMG Its Hot

Post by chrisd2211 » Thu Apr 24, 2008 3:47 pm

Hi there I have an issue with overheating only just started, there was a lot of COLD water spewing from underside of van (Drivers Side around underside mid engine). When I removed Rad cap more pressurised cold water came spewing out which i thought was odd for a over heating van (By the way the fans were running) having had a quick look under I can see NO damaged or split pipes which leads me to believe that perhaps the water pump may have gone but not knowing or able to see the water pump I cant be sure can someone help please !! firstly where is the pump?? and secondly any other assistance would be appreciated. Thanks Chris. ( I knew I should have gone to College) :-(
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Re: Losing water .......OMG Its Hot

Post by francophile1947 » Thu Apr 24, 2008 4:41 pm

If it's pressurised when cold, it sounds like the dreaded head gasket has gone - has it actually overheated at some time? Doubtless somebody with more knowledge than me will post.
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Re: Losing water .......OMG Its Hot

Post by maxheadroom » Thu Apr 24, 2008 4:50 pm

chrisd2211,
water pump is right at the front of the engine behind the top pulley. If it's that that is leaking water will run down the front of the engine. Head gasket should not leak water from the out side of the engine.
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Re: Losing water .......OMG Its Hot

Post by francophile1947 » Thu Apr 24, 2008 4:55 pm

maxheadroom wrote:chrisd2211,
water pump is right at the front of the engine behind the top pulley. If it's that that is leaking water will run down the front of the engine. Head gasket should not leak water from the out side of the engine.
Agreed, but would a leaking water pump pressurise the system? :?
John
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Re: Losing water .......OMG Its Hot

Post by chrisd2211 » Thu Apr 24, 2008 5:27 pm

francophile1947 wrote:
maxheadroom wrote:chrisd2211,
water pump is right at the front of the engine behind the top pulley. If it's that that is leaking water will run down the front of the engine. Head gasket should not leak water from the out side of the engine.
Agreed, but would a leaking water pump pressurise the system? :?

is it possible it could be the thermostat not opening/closing properly?? To the best of my knowledge it hasnt happened b4
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Re: Losing water .......OMG Its Hot

Post by Aethelric » Thu Apr 24, 2008 5:56 pm

There are only three ways to pressurise the system.
By pumping gas in from the engine, which means a crack or a gasket gone,
By heating air up in the system - the usual method,
By water boiling somewhere in the system.
If the water pump was gone, then water would boil in the head and the radiator could still be cold.
If the stat was stuck the top of the radiator should still be hot.
There may be other reasons too. I'd check the pump first.

Dave
chrisd2211

Re: Losing water .......OMG Its Hot

Post by chrisd2211 » Thu Apr 24, 2008 6:08 pm

ok heres a bit more info if I squeeze and release the water pipe in fornt of the alternator there is a clicking noise which is coming from a part that is mounted directly behind the dipstick would i be right in thinking that is the thermostat also having inspected the water on the road it is fairly clean the water puddle was just in line with the back of engine/gearbox, the radiator is stone cold if thats any indication. regards Chrisd2211
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Re: Losing water .......OMG Its Hot

Post by The Great Pretender » Thu Apr 24, 2008 10:02 pm

chrisd2211 wrote:ok heres a bit more info if I squeeze and release the water pipe in fornt of the alternator there is a clicking noise which is coming from a part that is mounted directly behind the dipstick would i be right in thinking that is the thermostat also having inspected the water on the road it is fairly clean the water puddle was just in line with the back of engine/gearbox, the radiator is stone cold if thats any indication. regards Chrisd2211
Have you checked that the head is free of air?
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Re: Losing water .......OMG Its Hot

Post by chrisd2211 » Thu Apr 24, 2008 10:28 pm

dont wanna seem thick ;-) How do i check the head for air??? thanks
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Re: Losing water .......OMG Its Hot

Post by francophile1947 » Fri Apr 25, 2008 2:14 pm

Just been re-reading your original post. Did you remove the radiator cap or the expansion tank cap when the cold water gushed out?
Is water still leaking?
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Re: Losing water .......OMG Its Hot

Post by GICarey » Fri Apr 25, 2008 3:28 pm

chrisd2211 wrote:ok heres a bit more info if I squeeze and release the water pipe in fornt of the alternator there is a clicking noise which is coming from a part that is mounted directly behind the dipstick would i be right in thinking that is the thermostat
if it is (i dont have a bongo yet) then this might be the valve in the thermostat - I was reading though a huge overheating thread on here somewhere, which tells of a small valve in the 'stat, which is there to allow air to rise up the system when bleeding, etc, but which closes when water trys to move through the opposite direction. Someone said they could hear this clicking when manipulating the pipe.

Dont think this would indicate the correct operation, or otherwise, of the 'stat (though, you could take it out and submerge in hot water (82oC+) to see if it operates as expected.
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Re: Losing water .......OMG Its Hot

Post by chrisd2211 » Fri Apr 25, 2008 7:46 pm

francophile1947

it was the expansion tank cap i removed not radiator, do you think it could be the stat valve??
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Re: Losing water .......OMG Its Hot

Post by francophile1947 » Fri Apr 25, 2008 8:03 pm

I was hoping it was the rad cap, as mentioned in your earlier post, cos' the water would have gushed out from there without pressure in the system.
Can't see how it could be the stat valve - that's just a small "pin" that keeps a hole open to let the air through when bleeding the system.
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Re: Losing water .......OMG Its Hot

Post by The Great Pretender » Fri Apr 25, 2008 9:49 pm

chrisd2211 wrote:dont wanna seem thick ;-) How do i check the head for air??? thanks
If you pm me I will talk you through it. :wink:
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Re: Losing water .......OMG Its Hot

Post by chrisd2211 » Sat Apr 26, 2008 9:14 am

More info.......Having just looked further I have found a split hose (the one over starter motor) but there is an underlying problem I think ........The top radiator hose warms up with engine running as is the water in the rad but the bttm rad hose is stone cold as is the water in the header tank also passenger side there are two metal pipes clamped to the chassis which I think are heating pipes one again is stone cold the top one warms up but this could be normal right ?? I dont think I have cooked the head as the water in rad is a clear rusty brown if that makes sense . I hope this helps.
Regards Chrisd2211
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