Overheating has blown off expansion tank sender

[langb20]

Hi Tosh,
Ouch, sorry to hear your predicament.
Best case sounds like your cap that fell to bits didn't do it's job (not surprising considering the state you mention) that is THE pressure relief for the system as it warms up and expands. Supposed to open ('relief') at 1bar i think, so if this doesn't happen, the next weakest thing goes - your sender by the sounds of things. Can't believe the threads are still in there and the top blew off the sender, never seen that happen. did the engine water temp overheat massively? as temperature gauge is a sign of pressure, they're linked - it's how the water stays liquid above 100C - by being at pressure.

But then, hate to say (worst case) bits blowing out the water system due to too much pressure could be head gasket gone, especially being a diesel (v. high compression), might explain water not going round aswel.

You should be able to run the engine up from cold with the expansion tank cap off, if it's spouting water everywhere then your head is gone
is the water disappearing anywhere? perhaps an air lock in the system? if your water pump is duff, the engine will heat up uber quick and your bypass pipe will likely stay cold (that's the one from the pump up the side of the block into the head near injector#1 if my brain remembers correctly)

hope the vw gods shine on you sooner rather than later
best of luck
Brent

[toshT25]

Thanks mate for the reply its getting pretty lonley up here on this mountain, think I,ll try and move it into town as its only 1km and from cold i,ve a good 5 mins before it warms up and starts steaming too much. Reckon it´ll idle for a long time though and stay ok its when you start driving it goes hot.

Best case sounds like your cap that fell to bits didn't do it's job (not surprising considering the state you mention) that is THE pressure relief for the system as it warms up and expands. Supposed to open ('relief') at 1bar i think, so if this doesn't happen, the next weakest thing goes - your sender by the sounds of things

That makes sense as I did blow through the pipe end to make sure it was open so thats why it filled up the top up tank. If I´d had to guess before this happened I would have thought the top up tank top would have been weaker but then the pressure has to goe down the narrow feed pipe so yeah I hope the vw god is shinning. The fact it happened 5mins after the valve falling apart gives some positive out come but guess I´m going to have to wait till wednesday to find out (if vw spain do them) or I can find a 15-18mm-ish nut to screw in to seal it off and get the thread out, hacksaw blade I have so I´ll try that tomorrow if its not raining all day.

if it's spouting water everywhere then your head is gone

Its fine idling up from cold to warm. Do you mean if its spouting water everywhere when its cold/straight away or when its warmed up as its nice and still.

if your water pump is duff, the engine will heat up uber quick

I´ve only let it warm up fully once since it happened but I reckon it would have taken a good 10mins from cold for the temp guage to get to normal. After five mins and the guage just showing I took it down a dirt track for about 1km there and back and when accelerating back thats when it starts steaming and spitting, hmm.

Oh theres another prob too one of the injectors is pissing diesel all over the engine, the one that goes towards the front by its self. I used some araldite, it worked but then started to pi$$ from another pin hole further down the tube. Yeah I was driving off the motorway with steam, coolant and diesel vapour. But I´m looking on the positive side as I think thats being pissing a while as my mpg went way down. I just put it down to the cheap tractor diesel they use down here and.

Would putting some thinner oil lower the compression or has the oil nothing to do with the compression here. I just need it to last another 250miles to santander then I´m home.

Thanks again.

[toshT25]

Also the no water coming out as me stumped is it supposed to flow out soon as you start it up from cold.

Cheers.

[langb20]

Hi Tosh,
Yeah I was saying if water is spouting out from cold with the cap off then it the head gasket. Somewhat good news there then if that's not the case. Not sure if there is to be any turbulence in the water tank when engine running, maybe not until the thermostat opens up, will check mine tomorrow.
You got access to a hosepipe to try flushing the system through? ideally get some pressure on it rather than just refilling with bottles - open up the heater valve in the cab aswel, don't want any air locks there.

Hopefully you can get the system sealed up so that it can hold pressure, because the engine will want to turn the water to steam otherwise and the water pump don't do vapour too well. fingers crossed vw spain will deliver. So long as the replacement cap does it's job then you should be ok, should be able to blow but not suck through cap. when you get it back, don't forget to sort the antifreeze out cos winter is coming

If your injector pipe is leaking it must be running lumpy as hell? I got some air in mine when swapping engine over, the air compresses and the injector won't reach pop-open pressure so no fuel to cylinder. sounded horrific. hope you not got that problem, perhaps it's the run-off piping (rubber?) that joins all the injectors, i had a leak there too, no great pressure there mind, just fuel economy is bad and it stinks. Something to fix sharpish at £1.20 a litre!

Don't think the oil will affect compression, not sure, but seems a stretch.

Defo worth having breakdown cover in future then, towing without cover is ridiculous (how do they sleep at night???). hopefully it won't come to that
Best of luck,
Brent

[toshT25]

Thanks again Brent,

Good news, I managed to get it into town and that must of unblocked an airlock as I´ve managed to get some water coming through. Going to search the forum on how to bleed it as the haynes for the petrol engines say it should be revved and then raise the front end 400mm higher than the rear but the justkampers manual for diesels says just let it tick over until all the air bubbles have gone. (me thinks rev,rev,rev). Theres a few mechanics here too so I´m thinking I´ll let them check it out once I´ve done it, if I do it that is. Well I´m not thinking I´m going to, it´d just be nice to get it running ok so I´m not held over a barrel.

I´m pretty confident the head gasket is ok now (thanks) as its nice and smooth until it gets hot and then spits. I fixed the sender as well, the thread came out easy once the o ring came out so some super glue and araldite to fill the inside totally, it´d take some pressure to push out the 2 probes. Looks like its now stronger than before if you can imagine it but I´m not going to risk it so I´ll order a new one wednesday, Spanish 2 day national holiday at the moment would you believe.

I fixed the diesel leak with nural 27 which looks to be holding but that whole area needs a tidy/new hoses when I get home as its all very sweaty if you no what I mean.

Anyways things are looking up and I´m starting to eat again

Thanks mate, I really appreciate your help.

[langb20]

Hi Tosh, good news then, glad to hear it

This thread is the one you want for bleeding advice
http://www.brick-yard.co.uk/forum/forum ... ing-system

enjoy the bank holiday, must be not much difference over there in terms of productivity? all those siesta's n all! lol

[toshT25]

Hi again, got as far as Burgos , parked up for the night only in the morning it won´t start, first time in 7000 miles. It just turns over and coughs out medium grey sooty smoke. So near and yet so far I´m kicking myself I didn´t drive all the way to santander while I had the chance. So I haven´t a clue. Overheating may have damaged something or I haven´t bleed it right and overheated the top part but I´m sure I did it ok. I did find that link for bleeding and followed it to a t but I don´t know. Stange she was purring like a kitten that had just had a hot bowl of milk and a belly rub for a good 130 miles, stopped for 30 mins drove another 20 miles everything fine and parked up.

Had to change the fan belt too as the alternator light kept coming on so that may be why it started getting hotter than usual (water pump) in the first place. Anyway I´m done here, just trying to figure out whether brittany ferries let towed cars be towed on and have a tow truck waiting at the other end or you have to go with a tow truck which if so, hmm.

Anyways I´m at the point where I´d just rather dump it and get on a plane back but I´ll have one last go but "pooh" its doing my head in.

Thanks mate, I´m going to post another thread see if anyone knows whats up, what I,ve done but lets us know please if you´ve any ideas, you know, in regards this sooty smoke. It maybe salvageable if I get it to a main dealer.

Cheers.