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Replace Water Pump when replacing timing belt?

I have a 1999 Honda Accord V6 with 101,000 miles - I am the second owner and the car was meticulously maintained and garage kept by the original owners. I need to have the timing belt replaced and am wondering if I should have the water pump and/or other parts replaced during this repair? Economic prudence is of the essence.
thank you.

I think it all depends on how long you plan on keeping this 12 year old car.

Since the water pump is driven by the timing belt, if you don’t replace the pump now, and if it starts leaking later, you will wind up paying essentially the same labor costs later that you are paying now for timing belt replacement. Or, in other words, if you get the water pump replaced proactively at the same time as the timing belt, you will pay little labor cost for the water pump’s replacement. If you are planning on keeping this car for more than another year, I would say that this would be economically prudent.

However, you may like gambling on the chance that the water pump will not develop problems while you own the car. That could turn out to be a good bet, or it could turn out to be a costly one. After all, you are now about 3 1/2 years late on replacing the timing belt, so maybe you will luck out with the water pump the same way that you have lucked out with the timing belt.

I think it all comes down to how risk-averse you are.
Personally, I would replace the water pump, serpentine belt, timing belt, and all belt tensioners at the same time. Paying a bit more at this point could wind up saving you money over the long term.

Follow VDC’s advice. Not doing so would be penny wise and pound foolish.

It’s really a no-brainer. Preventative maintenance is money in the bank.

Yes, they should replace the water pump, tensioner, etc. You have an interference motor meaning that a broken belt bends valves and pistons which in effect kills the motor.

An old water pump can go bad, start to leak, or even worse the bearing in the pump can give out and lock up the pump and shred the belt. A bad tensioner can come apart and shred the belt. A shredded belt breaks and your motor is toast.

As noted before - yes on the water pump.

And as UncleTurbo also mentioned, a new timing belt tensioner is a must. Most places will do this as a matter of course, but not all.

So - new pump and new tensioner.

I agree with the others. I have seen too many people gamble on this one and lose, and sometimes the loss is their engine. To quote the old Fram commercials: “pay a little more now, or pay a lot later” (even though I prefer to pay a little more still for a Purolator or Wix filter).

It all depends on trust. How long will the bearing in the water pump last? Nobody knows when it will fail. We don’t know how long the seals will last either.

Will the old water pump stay or will it go. There is a sort of “Clash” here. If it goes, there could be trouble; if it stays it could be double.

Replace the pump. It is only a few dollars more since the labor is going to already be paid for.

I do my own timing belt/water pump changes and sometimes if the water pump isn’t extremely old I’ll skip the pump and just do the timing belt to save time and has always worked out fine, but I have a non interference engine and if the water pump seizes and damages the belt there’s no other damage except the belt. If my car had an interference engine as yours does I’d never skip the water pump for fear of destroying the engine if it failed. If I were paying someone $75-$100 per hour to work on my car I’d also go ahead and have the water pump replaced while 80% of the work is already finished instead of risking having to pay someone twice.

Toyota recommends INSPECTING THE WATER PUMP when the timing belt is replaced. And, they do not replace it if it passed the inspection criterion. My Sienna is due soon for timing belt. The first change, I asked about the water pump, and the dealer told me Toyota recommended inspection. They also said a lot of people wanted it replaced, and they will do it if requested even though they realize it does not need to be changed.

It is interesting how often people here tell posters to follow the manufacturers recommendation on oil changes, etc. But when the manufacturer says inspect water pump and do not replace if it passes, no one wants to talk about the manufacturer’s recommendation

I would suggest to OP to find out what Honda says to do with your water pump.

I the reason most people suggest changing the water pump when replacing the timing belt (myself included) is because while the timing belt is off it only takes a short time to replace the water pump and if it’s an interference engine it’s just extra insurance. I know I’ve skipped water pump replacement a few times on non interference engines and have them go out before the next timing belt change interval. In a case where the person is having to pay a mechanic to do work, they end up paying labor twice if this happens. Years ago when water pumps were driven by V belts I’ve checked water pumps for play in the bearing when replacing the V belt only to have the bearing go out shortly afterward causing the water pump to start leaking. I was recently replacing the timing belt on my '02 Ford Escort and even though the water pump bearing checked good I replaced the water pump. The extra costs for a lifetime warranty water pump was under $50. and added about an extra hour to the time it took me to do the job where if I’d had to start from scratch to do the water pump at a later time it would have taken 4-6 hours to disassemble, replace the water pump and reassemble everything.

It is interesting how often people here tell posters to follow the manufacturers recommendation on oil changes, etc. But when the manufacturer says inspect water pump and do not replace if it passes, no one wants to talk about the manufacturer’s recommendation

Well, I don’t see the inconsistency there. Don’t do less than the manufacturer says. It’s OK, and sometimes wise, to do more than the manufacturer says.

“no one wants to talk about the manufacturer’s recommendation”

Like when Honda recommends listening to the valves at 60,000 miles to “inspect” valve lash?

nicely put, shadowfax

How does one inspect a water pump and determine that it will still be fine in say 2k miles?

The last Mitsubishi my daughter owned (bought used) had a recent timing belt replacement and the tensioners and water pump had been determined to be fine at that time. (Daughter waded into this without talking to me first.)
Not many months later (less than a year) I determined that the tiny coolant leak on the garage floor was due to a leaking water pump and after removing the upper belt cover found the new belt was saturated and softened with coolant.
So, I tear it all apart and redo it correctly this time.

Luckily, this was caught and repaired before that softened belt decided to strip or break on an interference fit engine.

The timing belt is driven by the water pump??
I thought it was driven by the crankshaft.
In fact, those of you who say that it is driven by the pump have to be wrong, as there is no way to get the timing right from the pump.

“The timing belt is driven by the water pump??”

No, the water pump is driven by the timing belt.

I thought that the water pump was always driven by an external (fan) belt, or serpentine belt.

Not always.