Changing the waterpump with timing belt - why??

[Condi]

4key said:

Quite a few cars came with crappy plastic impellers.

Being French, if there is a crappy way of doing it, they've probably done it.


I shall cave to popular opinion and reach into the bottom of my pocket. Hang the expense!

[Condi]

Willy Nilly said:

Do you get a company car flogging grain, or whatever you do now?

I had to get a pry bar and WD40 to my wallet only this morning, but broke the handle on the pry bar

Im not a grain peddeler, and dont get a company car. Others in the office do, but they are a good few rungs up the ladder or do mega miles for work. Wouldnt mind getting one, brand new BMW 3 series for £100/month all in, although some have Mondeo's, Audi's etc. One lad's wife works at Merc and he has a brand new Merc every 9000 miles through her. She has her own company merc as well. Nice little perk if you can get it.

[Davie]

I'd always change the water pump at every second belt change at the very most. My wee sister's car had it's belt, idlers and tensioner changed at the recommended 80,000 miles (4ys/40k, whichever first intervals) and ye olde cheapskate previous owner opted not to change the belt. It got to 100,000 miles and started grinding. Full strip down revealed the pumd had collapsed. So, pump and anotehr timing belt kit and it's go to go again.

For the want of £25, opting not to change the pump defies logic...

[BFG TERRANO]

In theme with this thread.... I also change light bulbs in pairs.... ie if 1 side blows i change both. My theory is, if one has gone the other cant be far behind! Weird i know but thats what i do!

[RizzoTheRat]

I'm a tight wad, headlight went the other week so I bought a pair but only changed one and the others the glove box while I get maximum value for money out of the remaining original

[With these feet]

I think the terminology is "False Economy".

Sure youre saving short term, but if as per VW engines the pumps st themselves between belt changes, its better to do some preventative maintenance rather than facing a bigger bill.

[Condi]

RizzoTheRat said:

I'm a tight wad, headlight went the other week so I bought a pair but only changed one and the others the glove box while I get maximum value for money out of the remaining original

Headlight went in one side so I bought one bulb? Makes sense to me... No point buying 2 when you only need one!

[redtwin]

Condi said:

4key said:

Quite a few cars came with crappy plastic impellers.

Being French, if there is a crappy way of doing it, they've probably done it.

My rather non-French BMW was equipped with a crappy plastic impeller water pump. Based on strong recommendations from another forum I was on, I changed it even though the car had no cooling issues. Upon removal I found that the vanes had quite deep cracks and I was able to break a couple off using relatively light finger pressure.

Are you panicking yet?.

[saaby93]

Probably best to change everything on the engine at the same time as changing the cambelt just in case?

What to do about cars with a 200,000 mile timing chain

[wheedler]

Condi said:

Whats the thinking behind this? Water pumps dont go that often do they? It seems like a way of making the garage some extra cash because they can, Ive never known a waterpump fail and yet everyone seems to change them when the timing belt is off.

I know its 'only' £30, but when Im only paying £120 or so for the cambelt its still another 25% which might not need paying.

My sister only last year had the waterpump go on her 02 passat, yep she had to scrap it

[With these feet]

saaby93 said:

Probably best to change everything on the engine at the same time as changing the cambelt just in case?

What to do about cars with a 200,000 mile timing chain?

Generally they dont drive water pumps off timing chains.

I did the chain on my 47K 2002 transit about 5 months ago due to the dreaded death rattle on start up.
Could have just changed the hydraulic tensioner but while in there did the chain and guide as well.
Was the difference between a bill for parts of £50 or £250. I thought I'll keep this for a while so changed the lot. Least I know its been done and should last quite a while. Water pump is driven off the aux belt and didnt show any signs of wear.

[AJB]

Condi said:

Whyfore? In my line of business we change things when they need changing, not because 'you can'.

As others have said, it's not so much that 'you can' as that on many cars you'll have to re-do a whole lot of work if it needs doing later. And it's often more that £120 labour for a cam belt. Doing it is insurance against having to do the work again.

Condi said:

I think Ive only changed one because it was 'gone', 99% of the time its just the gaskets which leak, put some new sealer on and they are good again.

I've had a couple of water pumps need to be replaced, both time with the seal on the shaft starting to leak even though the bearing was fine. One was prob 150,000 miles, the other maybe 95,000.

So when I got the cambelt changed on my Octavia at about 60,000 miles it seemed worth putting in a new water pump as it felt that there was a reasonable chance it could start leaking before 120,000 miles and it would have been really annoying to have to get the belt taken off again for that. Plus the unreliability and potential engine damage etc from a coolant leak if it did start to go.

But it's like insurance. You look at the premium, you look at the potential risk, and you weigh it up. If it had only been £120 for the cambelt change, then I'd have been a lot less likely to get the pump done as a precaution, as the risk I was insuring against would have been lot smaller.

[AJB]

Condi said:

RizzoTheRat said:

I'm a tight wad, headlight went the other week so I bought a pair but only changed one and the others the glove box while I get maximum value for money out of the remaining original

Headlight went in one side so I bought one bulb? Makes sense to me... No point buying 2 when you only need one!

I'd buy 2, as the other's likely to go at some point and I like having spares "in stock". But I'd only fit 1, as I'm also a tight wad and also want to get the maximum value/life from the other.

If there was a huge amount of labour involved though (eg remove bumper and radiator to access headlight), and then it was easy to access either headlight whilst it was apart, then I'd probably fit 2 new bulbs. And that's the water pump example.

There's also the risk of something being done incorrectly, and if the cambelt has to be taken off and replaced twice then that risk doubles.

[saaby93]

AJB said:

There's also the risk of something being done incorrectly, and if the cambelt has to be taken off and replaced twice then that risk doubles.

Ah that old problem
whats the risk of cambelt failure vs the new one being fitted incorrectly?
or keeping a perfectly good water pump vs misfitting a new one with unknown provenance?
Dont service the car just before a long trip?

[marmitemania]

People are also forgeting that when you fit a new timing belt and re tension it is natrualy tighter than the one that has come off, this puts extra pressure on the water pump that was not there before. I have done 100's of timing belts and will not do it without changing the water pump.

[saaby93]

marmitemania said:

People are also forgeting that when you fit a new timing belt and re tension it is natrualy tighter than the one that has come off, this puts extra pressure on the water pump that was not there before. I have done 100's of timing belts and will not do it without changing the water pump.

Surely the idea of the tensioner is to maintain the smae tension through out the life of the belt and apply the same tension to a new belt?
Who changes the tensioner with each cambelt too?

[Davie]

saaby93 said:

Who changes the tensioner with each cambelt too?

Me...

[wolf1]

saaby93 said:

Surely the idea of the tensioner is to maintain the smae tension through out the life of the belt and apply the same tension to a new belt?
Who changes the tensioner with each cambelt too?

When i change timing belts it's a complete kit including tensioners, idlers and waterpump if driven by the timing belt. If you just want a belt only change then you can go elsewhere as I won't be fitting it.

The only exception to that is any alfa twinspark i have done a full kit change on previously as the belt itself is changed every 30000 or 3 years. So they get a full kit every second belt.

Edited by wolf1 on Sunday 2nd December 19:37

[SuperHangOn]

On a lot of cars its the tensioner rather than the belt itself which goes...

[With these feet]

Actually to be completely pedantic, it should be a cam belt kit and water pump.

Tensioners fail either due to poor fitting or the pulley disintegrates - the latter due to the insistence on manufacturers using plastic pulleys. The majority of tensioners now have a self tensioning system in them - not like the old CVH "screwdriver wedged in and nip the bolts up" method or the Vauxhall OHC with rotating water pump system. Unless set up correctly when fitted by lining up the markers and then rotating the engine, they can shorten the belt life drastically. Equally I would not trust a tensioner that has done 60,100, 120k to work forever.