Club 80-90 Forums

Got the T25 w/c 1915 rebuilt and replaced.

The whole affair is running in at around 300m.

It gets up to temp quick and stays very high. This was the problem on the old engine too.

There is a lot of pressure in the rubber hoses that normally allow water to squeeze through into the pressure tank.

I suspect that this is correct and it will force past the pressure cap if the temp and pressure goes too high.

It is plain water for now and will get its antifreeze on completion of run in.

Turn off the engine without the fan having cut in but after a while start up and the fan cuts straight in!

This is all odd and I don't want to chance a newly rebuilt engine.

Anyone a w/c guru out there?

The one sentence that bothered me was 'gets up high and stays there'.....obviously it should rise quickly to about half way but not any higher whilst actually driving. Once at a stand still with the engine still running, the needle will creep up over 1 - 2 minutes (because there is no airflow through the radiator) the 1st speed on the fan should really be clicking in a needles width past half way, staying on for 30 - 45 second bursts and taking the needle back to half way.
If it is going any higher before the fan cuts in then I suggest you have a problem.
Either the radiator is full of silt and needs changing or the thermo switch is faulty or both.
Yes the hoses should get hard, but as you say the Darlek cap should release pressure once it hits around 1bar (15PSI)...if in doubt fit a new 'genuine' cap.
Caps about £13, thermo switch about £14 radiator around a ton......fit the cheap parts first and see how it goes.

Martin

Faulty thermostat will restrict coolant flow
Beed it with the baxter method

Have you flushed the radiator through with a hose pipe, I have read instances of them being half full of silt. As the others have said, start cheapest and work your way through... also antifreeze is a coolant too... it may bring the overall temperature down a few degrees when fitted.

Nitmoi wrote:It is plain water for now and will get its antifreeze on completion of run in.

It isn't just anti-freeze. It also protects against internal corrosion.

I concur with pionte that it's definitely worth flushing the radiator through as a matter of course, especially if it's been filled with water previously. The amount of crud and rusty coloured water that came out of mine was pretty amazing, although to be fair it was made a lot easier as i had the engine out. The metal rail that goes round the engine on mine was also blocked in different places. It still baffles me now how it made it home without overheating (it was bang on central for the 150 mile journey home!).

I've also just had a recon engine put in mine and am currently running it in to 500 miles, however, for piece of mind also changed the dalek cap, water pump, thermostat and sensor switch (which had seen better days).

Nitmoi wrote: There is a lot of pressure in the rubber hoses that normally allow water to squeeze through into the pressure tank.
I suspect that this is correct and it will force past the pressure cap if the temp and pressure goes too high.

300CE wrote:for piece of mind also changed the dalek cap,

= I personally have had (a good few years ago) a Dalek cap that was not releasing pressure. It resulted in the head to crankcase seals getting damaged, which in turn resulted in a LOT of hassle, culminating in a "new" engine (after the first replacement turned out to be a pile of pooh). Take no chances here, buy a proper one (NOT GSF / JK one), from Brickwerks

Oh, and yes, that bleed rail around the lip of the engine bay (later vans only I believe, might be wrong though ) they can get blocked, esp at the "T" pieces. This is what caused my over pressurising (with faulty cap) The water in one or both heads has nowhere to go and boils, creating a LOT of pressure (if cap faulty). There were some good pics of what was found in blocked bleed rail pipes, but I cannot find them now Redweld etc can cause blockages there, with those pipes being so thin and high up (= if any air is in there <"bleed rail"> )

ghost123uk wrote:

Nitmoi wrote: There is a lot of pressure in the rubber hoses that normally allow water to squeeze through into the pressure tank.
I suspect that this is correct and it will force past the pressure cap if the temp and pressure goes too high.

300CE wrote:for piece of mind also changed the dalek cap,

= I personally have had (a good few years ago) a Dalek cap that was not releasing pressure. It resulted in the head to crankcase seals getting damaged, which in turn resulted in a LOT of hassle, culminating in a "new" engine (after the first replacement turned out to be a pile of pooh). Take no chances here, buy a proper one (NOT GSF / JK one), from Brickwerks

Oh, and yes, that bleed rail around the lip of the engine bay (later vans only I believe, might be wrong though ) they can get blocked, esp at the "T" pieces. This is what caused my over pressurising (with faulty cap) The water in one or both heads has nowhere to go and boils, creating a LOT of pressure (if cap faulty). There were some good pics of what was found in blocked bleed rail pipes, but I cannot find them now Redweld etc can cause blockages there, with those pipes being so thin and high up (= if any air is in there <"bleed rail"> )

There was also a crack in the header tank on mine, so bought a new one of those from brickwerks - i also caned the credit card and went for the stainless coolant pipe as the mild steel one was on it's last legs as well. Brickwerks are now selling cheaper dalek caps - will be getting a couple to carry round in the spares kit:

http://www.brickwerks.co.uk/index.php/h ... arket.html" onclick="window.open(this.href);return false;

Also, a pic of my engine so you can see where the stainless pipe is in case you want to check yours Nitmoi (please note the oil breather pipe is now in a more suitable position since this photo was taken :

Thank you so much everyone.

Just to add to the concern, a pool of oil is developing under and 1/2 the oil is missing so got to find whare that is coming from now!

Anyone know a willing t25 mechanic in Cambridge area for second opinions?

Most just won't have anything to do with them! W/c that is!