300Tdi Cooling System

battenberg · Mar 28, 2008

I was getting strange readings on my temp guage, so I replaced the sender and while I was there threw in a new thermostat.
I didnt drain the system, rather let it leak out while swapping over quickly and top it up afterwards.
Now when I run the engine, I get a strange sound like the water pump is screetching running dry every now and then, every 10-20 seconds for a second or two.
I also topped up the cooling system via the plastic plug on the top of thermostat housing before running the engine to try to avoid any air lock. (BTW this plugs threads were shagged... anyone know what they are called?)
Could this be an airlock in the cooling system or a sign my water pump is on the blink... any clues??

discomania · Mar 28, 2008

Could it just be the belt or pullys.

Try getting some lubricant into the backs of the pullys and then spray some water onto the belt and see if it disappears. It could be the coolant pouring into the bearings that has caused a squeek.

rollin danny · Mar 28, 2008

Dont know if this is advisable but my mate blew into the expansion tank while plastic plug was out and coolant with air bubbles in it came out.Now thats what I call a blow job!

thebiglad · Mar 28, 2008

battenberg said:
I was getting strange readings on my temp guage, so I replaced the sender and while I was there threw in a new thermostat.
I didnt drain the system, rather let it leak out while swapping over quickly and top it up afterwards.
Now when I run the engine, I get a strange sound like the water pump is screetching running dry every now and then, every 10-20 seconds for a second or two.
I also topped up the cooling system via the plastic plug on the top of thermostat housing before running the engine to try to avoid any air lock. (BTW this plugs threads were shagged... anyone know what they are called?)
Could this be an airlock in the cooling system or a sign my water pump is on the blink... any clues??

Can't help to much with the rest, but the plastic plugs are crap and have been known to fail, so the easiest/best solution is to replace them with 1/2 inch brass male blanking plugs - works a treat and about 50 pence a go !!

Available from DIY and plumbers merchants.

The Mad Hat Man · Mar 28, 2008

Just get a couple of domestic radiator drain valves - same thread and yu got a built in bleed system

.

david451 · Mar 28, 2008

The Mad Hat Man said:
Just get a couple of domestic radiator drain valves - same thread and yu got a built in bleed system.

Great idea, but I don't fink there's enough room above the thermostat, I used a straight coupling and it was too long and had to cut one end off.

david451 · Mar 28, 2008

battenberg said:
I was getting strange readings on my temp guage, so I replaced the sender and while I was there threw in a new thermostat.
I didnt drain the system, rather let it leak out while swapping over quickly and top it up afterwards.
Now when I run the engine, I get a strange sound like the water pump is screetching running dry every now and then, every 10-20 seconds for a second or two.
I also topped up the cooling system via the plastic plug on the top of thermostat housing before running the engine to try to avoid any air lock. (BTW this plugs threads were shagged... anyone know what they are called?)
Could this be an airlock in the cooling system or a sign my water pump is on the blink... any clues??

Seen this many times after working on the cooling system, normally water causing the belt to slip and once it's warmed through it should go away. The water lies around and gets pulled or runs into that area and you get the belt slipping until it throws it off.

Run your engine with the cap off for a bit utill it warms and the water starts circulating then if alls ok fit cap and bring up to pressure and check for leaks, and then go for a short run near yer home in case.

The blank plugs are crap I had one blow out, and as the threads indicate go for a plumbing fitting, but watch the clearance on the thermostat to bonnet.

battenberg · Mar 28, 2008

thanks for the tips... gonna head to B&Q for some blanking plugs

300Tdi Cooling System

battenberg

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discomania

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rollin danny

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thebiglad

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The Mad Hat Man

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david451

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david451

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battenberg

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