405 TD What causes head gasket to go?

I have a '95 405 TD 127,000 miles and am worried the head gasket may go as it's a common problem.

What causes them to blow?

Would replacing it with a new one (not a service requirement) allow another 120,000 miles before any danger of going?

Reply to
405 TD Estate
Loading thread data ...

In my opinion the main cause is overheating. On Peugeots there is a fine line between running temperature and overheating and if you don't notice the temp gauge rising, by the time the stop light comes on it is normally too late. Other than that it is imperative to use good quality antifreeze all the year round and change it every 5 years or sooner. I do it every 2 on my 307.

Reply to
nigel

Overheating often caused by sludged up waterways.

No not really. I had one go in a BX 1.9D at about 120K but that was straight out from the dealers and due to a sludged up radiator. My 1.9TD Xantia is going fine at 140K and has got quite hot on a long run up to Aberdeen from Norwich with no obvious damage. The main thing is to ensure the waterways are clean. Change your water and antifreeze at least every two years as Nigel suggests, five years is far too long on these engines. Keep an eye on the radiator too, make sure it isn't losing the fins or whatever you call that zigzag stuff.

Reply to
Malc

The sludge can settle in the radiator. So a coolant change every two to three years and keep an eye on the radiator, feeling around when the engine is hot for cold spots on the rad. Caught my Dad's BX TD with a few cooler parts on the rad at 140,000 miles, changed it and now at 160,000 it's still running strong.

-- r

Reply to
R

I've heard the head bolts may loose their torque over time which may contribute.

So what should I do... here's what i think...

Refill coolant now - with new and a known amount of antifreeze (and distilled water) , also find out if a 'header' is needed when filling to prevent air bubbles (which may relate to the pug 405 TD engine)

Do a compression test now (would like to do this anyway - I dont expect it to show up problems)

When I do valve clearances/timing belt check the torque of the engine bolts - should I undo then re-do them to check they are moving OK, or just check the max torque (or torque + angle?) Should I put new bolts in? I'll also consider putting a new gasket in - probably not much more work from this point.

Finally there is a simple adjustment I can make to up the power by upping the boost- maybe from 0.6 to 1 bar - will these measures be enough (definately new gasket and bolts?) to hold it together for another 100K miles?

Reply to
405 TD Estate

No don't use distilled water. It's actually an agressive solvent because it doesn't have any impurities in it. Ordinary tap water is quite good enough.

I seriously wouldn't bother. Check the torque if you feel like it but don't undo the bolts, just check they're up to torque.

Look, first you want to improve your reliability, then you want to undermine it by upping the boost. Make up your mind.

Reply to
Malc

No, don't touch them !

Just leave it all alone, and replace the headgasket *if* it pops. There's only a small chance of it busting - they don't all do it !

Erm, don't do that either ! Your chances of head-gasket failure will increase many times over with a power increase (higher boost = hotter intake air = hotter engine = overworked cooling system).

If you want a faster car, then buy one. Tuning old, high-mileage Turbo cars is a bad idea for obvious reasons. You need to be looking at a 406 Estate

2.2 HDi 130 - they'll happily make a *reliable* 160bhp or so with a bit of fettling.
Reply to
Nom

I've just spoken to our race mechanic who is a long established (20year) Citroen/Peugeot specialist, he's never heard this.

Change your coolant, but first check with a hot engine that you have even heat right across the radiator, that is most important. While it is empty, give it a good flush with running water, try and run the water both ways throught the radiator to get rid of any sludge. Don't fill with distilled water as correctly pointed out by other poster, it's agressively corrosive, if you want to be fussy consider buying pre-mixed anti-freeze from Peugeot/Citroen, but it's expensive and uneccesary.

Noooo... These are stretch bolts, don't mess with them, they are already tightened beyond their elsasticity. DO NOT DISTURB!!! When/if you change you timing belt, change the water pump. A lot of the sludge in these engines is minute bits of alloy corroded off of the water pump vanes.

Up the boost by 40%? That will increase the charge and put more pressure on the head gasket, I wouldn't, certainley not on an engine that I had worries about the head gasket.

-- r

Reply to
R

Does that mean I should replace it because the metal worn away means the pump wont work as effectively? Or it's likely to wear a lot more metal off? Is it possible to inspect / service them? If not its a new pump which would be $$$ (=A3=A3=A3) from Peugeot.

Is there a way to check the water is flowing OK? (the radiator check?)

Thanks

Ian

Reply to
405 TD Estate

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.