coolant pressure
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Ray
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coolant pressure
2.1 dj coolant pressure. Have had 3 failed radcaps in the last 3 months. System bled several times, rad renewed 4 years ago. This engine was a vw original recon (fitter thought it was new) fitted in 2006 and has only done 12000 miles since on lpg. Garage VW waterboxer experts say likely gasket. I am going to let them look at it in new year. It seems strange that the caps have failed as I thought with excess pressure the caps would open and close again rather than failing completely. New thermostat was fitted recently but still no difference. I thought I would just check the top thin pipe round the engine hatch before I get the heads off but I am sure they are OK. Looks like expensive time ahead . Any other ideas as the actual engine is running nicely.
Ray
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axeman
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Re: coolant pressure
firstly when you say rad caps do you mean the darlec cap? if so there was a batch of dodgy vag darlec about a year or so ago i went through a pair in about 2 months. which could explain what has happend too you. just a thought,
neil
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Aidan
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Re: coolant pressure
sniff test will proove if it's products of combustion in the coolant
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Simon Baxter
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Re: coolant pressure
usual signs of combustion gas entering the cooling system is a header tank that always ends up half full and a burp tank whose level rises on it's own.
Basically, if you lower the number plate flap and take the cap off and coolant pours out, and the tank in the engine bay is half full then chances are you need to start removing the cylinder heads.
Cheap header tank caps are rubbish, we know this. the genuine ones are good, they are made by Blau, Blau also sell some aftermarket ones which have the same guts as the VW ones but a different outer shape, these are also reliable.
If you've toasted 3 genuine caps then you have problems.
That stands for petrol and Diesel models.
A block test (or sniff test as some people call it, although before block testing fluid was readily available we always called a sniff test using and exhaust gas anylyser over the open header tank to test for combustion gasses) only seems to work on petrol engines, not Diesel.
You may also see a constant stream of bubbles coming into the header tank when the engine is running.
Basically, if you lower the number plate flap and take the cap off and coolant pours out, and the tank in the engine bay is half full then chances are you need to start removing the cylinder heads.
Cheap header tank caps are rubbish, we know this. the genuine ones are good, they are made by Blau, Blau also sell some aftermarket ones which have the same guts as the VW ones but a different outer shape, these are also reliable.
If you've toasted 3 genuine caps then you have problems.
That stands for petrol and Diesel models.
A block test (or sniff test as some people call it, although before block testing fluid was readily available we always called a sniff test using and exhaust gas anylyser over the open header tank to test for combustion gasses) only seems to work on petrol engines, not Diesel.
You may also see a constant stream of bubbles coming into the header tank when the engine is running.