Water pump design change in 1st Gen

Happy Thanksgiving!

I'll be thankful for the answer to an $800 question. I recently purchased a used 2003 Taco V6 4WD with 128k miles. The second owner assured me the timing belt had been changed by the first owner because the second owner's Toyota Master Tech said the water pump was an after-market pump and "for sure" the timing belt would have been changed at the same time. I later got to worrying that if he was wrong, my engine was toast if the belt broke. I subsequently learned that the timing belt is a non-interference type so would not ruin the engine. Big sigh of relief.

However, I'm still wanting to know if I need to change out the belt. A couple of mechanics said you can't see the water pump without opening stuff up so I called the Master Tech directly to see how he could tell there was an after-market pump on my truck. He said you can see part of the water pump near the thermostat. He explained that an earlier version of water pump put into the 1st gen Tacos used a silicone sealant embedded in two grooves. That pump design proved to be problematic (according to him) with frequent failures around 40k. That water pump was apparently replaced in later Tacos with one that used a gasket against a non-grooved face. He saw the latter in the truck I subsequently purchased.

Here's the kicker. When I asked when Toyota made the changeover in design, he said "2002 or 2003." Mines a 2003. If mine was manufactured with the newer design, then the pump hasn't been changed out (which matches the 4-year-old memory of the first owner). If it was built with the older design, then the non-grooved water pump suggests the pump for sure had been changed out with a good bet the timing belt was too.

Anyone out there able to tell me for sure what year the newer design of water pump was used? If not, any idea how to find that out? A particular problem would be if both designs were used in 2003. Would there be a way to know which went into my truck?

If I can't find the answer, then would you agree with the Tech that it is much more common for the water pump to start leaking before the belt breaks, so he suggested waiting until I detected leakage from the pump. What do you think?

 

It's a recently purchased truck and you're at 128k miles. If it were me, I'd change it all out (water pump, & timing belt). Anytime I buy a used truck, I do all the maintenance so I know its done and when it was done.

Aside from that - you don't have any information about the timing belt and you should probably get that done at a minimum. If you wait - what's the magic number of miles before you decide its the right time?

The water pump redesign is a non-issue. Doesn't matter what type you have currently. The failure is at the seal on the block not the functionality of the pump. A failure with the seal will only result in some leakage. My 96 tacoma leaked coolant slowly for 1.5 years before I could locate where it was coming from (water pump).

It's totally up to you ....to wait or not. But I'd be more concerned about the timing belt than anything because that's something that can break without any type of notice and leave you inconvenienced.

 

just what i was going to say..Usually, if the timing belt has been done, there should be a sticker on the timing belt cover saying miliage and such. If not, do it yourself.

 

I agree with your general advice, but unfortunately, I don't have that kind of money to make a repair that's not necessary. And if I can show that the truck was misrepresented to me, I'm hoping to get some of my money back. The seller told me it had already been done so I paid a price assuming that was true rather than factoring in an extra $800 repair. The seller was conveying the information provided to him by his mechanic. Both the mechanic and seller are upstanding guys and the seller is willing to help with a repair to some degree but he's broke too. So I'm hoping if I can show that the mechanic erred in his evaluation because he got the model year wrong, he might be willing to discount the repair. There's no sticker to show that it was done.