Toyota Tacomas are renowned the world over for being more durable than a sledgehammer, and more common than pennies. However, even these venerable little trucks have their problems. One of these is the water pump and its gasket replacement. In this article, we’ll go over water pump gasket replacement on both the 4 and 6 cylinder engines. Let’s get started.
Diagnosis (4Cyl Tacoma)
Verifying the Water Pump Leak
Of course, in order to replace a bad water pump gasket, you first need to make sure it is actually the water pump gasket that is leaking. This is simple. With the vehicle running, shine a flashlight toward the water pump, and watch for a coolant leak.
You will also be able to tell if you have a water pump gasket leak by checking the coolant level regularly. While a head gasket leak can also drain the coolant, you will notice that from the engine overheating and oil leaking, whereas, with a water pump gasket, it will start as a coolant leak and eventually become a coolant waterfall if left unattended.
Replacing the Gasket/Water Pump
If you are at the point where the gasket is leaking, and it has not been done at any point that you can remember, you may as well replace the water pump while you are in there, for peace of mind. Here is a picture of a water pump and its location on a 4 cylinder Toyota Tacoma:
If you are new to the Tacoma world, you will be pleased to know that the water pump on the 4 cylinders Tacoma is not driven off the timing belt; just the serpentine belt, so you can run into Autozone and have it fixed in the time it takes to finish a cup of coffee. For reference, a water pump kit for a 4 cylinder Tacoma costs $131.99, and comes with the gasket as well, along with a new fan clutch. Now, onto the actual gasket replacement process.
Replacing the Water Pump Gasket
Now that you have your parts in hand, it is time to get down to business. Here is the process to change the water pump gasket and the water pump if you are so minded:
- Get the necessary tools; vice grips, 10mm socket, 12mm socket, 14 mm socket, and a ratchet.
- Remove the fan shroud, if you still have it installed.
- Drain the coolant into a bucket, so you can dispose of it. If it’s clean enough, however, you can put it back in with some fresh coolant to top off.
- Unbolt the fan from the water pump pulley.
- Remove the serpentine belt. This is simple; loosen the belt tensioner and slide it off the pulley. You only need to remove the belt from the tensioner and water pump pulley. This will save having to reroute it later.
- Locate the water pump and remove the bolts.
- Take a razor blade and scrape the remnants of the old gasket from the block. You need to clean the surface, or the new gasket will leak.
- Install the new gasket and reinstall the water pump; you may want to use Loctite on the bolts.
- Put the serpentine belt back on and bolt up the fan. Install the fan shroud.
- Fill and bleed the radiator.
Replacing the water pump gasket or water pump on any Tacoma is a fairly simple process, especially on the older trucks. The one in the picture is a 2nd generation Tacoma, so plenty of room to work on it. Of course, regardless of the room, don’t do this while the truck is hot.
Diagnosis (6cyl Tacoma)
The V6 Tacoma is just as rough and tumbles as its 4 cylinder brother; while the V6 Tacoma is not quite as unkillable as the 4 cylinder model, it is still tougher than granite and boasts more power to boot. Popular legend holds that the Tacoma is the only object that Australian wildlife will not eat because it is so tough. If that is not a solid set of credentials, I do not know what is.
Verifying the Water Pump Leak
Verifying a water pump gasket leak on a V6 Tacoma is a little more difficult than with a 4 cylinder Tacoma. The coolant leak is still the same, but a little more difficult to detect, as you will probably need to track it down from where it is leaking in front of the oil pan or on the frame.
The water pump is driven off the timing belt, which means you will need to remove the timing cover and partially remove the timing belt. It is a little more involved, but it can still be done. Let’s get started. For reference, a water pump kit for a V6 2nd generation Tacoma is $252, but just the water pump is around $91.
Here’s a picture of the water pump location on a 2nd generation, V6 Tacoma:
Replacing the Water Pump/Pump Gasket
Since you need to remove the timing cover and the timing belt to change the water pump gasket, you should change the pump too; this is not a job you want to do twice. Now, here is the rather intimidating process to change the gasket and pump:
- Remove the fan shroud
- Remove the fan
- Remove the serpentine belt
- Remove all accessory pulleys: alternator, power steering pulley, and AC belt
- Remove the upper radiator hose
- Remove the power steering pump bracket, but do not totally disconnect the pump; just the bracket
- Remove the timing cover
- Next, remove the entire fan bracket assembly. It is easier to do this and lift it out as one unit instead of removing all the vehicle accessories bolted to it.
- Remove the AC compressor if you have it. Make sure to support it so as not to damage the lines.
Now that the timing belt and water pump are exposed, the hard part is upon you. Look at the camshaft and crankshaft pulleys. They will have little notches in them. Take a brightly colored marker and draw lines from the notches onto the timing belt. This will make it easier to line them up and ensure that the motor is correctly timed when you are done.
Take the appropriate size socket for the crankshaft pulley, and turn it clockwise until the notch on the crankshaft pulley is pointing at the timing mark that indicates 0. This means the engine is at the top dead center and therefore timed correctly for when you put it back together. Do not rotate any of the camshaft gears.
Now, locate the timing belt tensioner, and loosen the 4 bolts that hold it in. You want to back it out to maximum looseness without removing it completely. Now, remove the timing belt from the camshaft gears, and remove the central pulley between the two cam gears. This pulley keeps the belt tensioned along with the tensioner. Take a zip tie and attach it to the timing belt by the crankshaft pulley, so that it stays tight on the pulley and does not slip off.
Remove the thermostat housing. The spring side goes into the block when reinstalling. You do not need to replace this every time, but since you are already changing a water pump gasket, it is good preventative maintenance to change the water pump and thermostat as well. Now, look at the water pump. It is down below the cam gears, in between them and the crank pulley. There are 7 bolts; do not drop them.
Clean the gasket surface with a razor blade or something like a piece of sandpaper, but do not scrape too much, or the new gasket will not seal. You will need to use RTV or another silicone sealer, along with the new gasket that comes with the water pump. Otherwise, it will leak. Reinstall the new gasket with a little RTV, and torque the water pump bolts to 20ft-lbs. If you do not have a torque wrench, nice and tight will do.
Now that you have done that, reinstall the thermostat, and double-check to make sure everything is installed correctly. Put the timing belt back on the cam pulleys; make sure the marks on the belt line up with the notches on the gears.
The tensioner should be tightened enough that the timing belt is not slack, but not so tight that there is no give. It will snap otherwise. Reinstall the center pulley. Bolt the timing cover back in place, and reinstall the fan assembly. From there, you can reinstall the accessory pulleys (AC, alternator, power steering), the upper radiator hose, and the fan.
It is best to wait about 24 hours before starting the truck to bleed the radiator, to give the RTV time to cure, but if that is not possible, about 15 minutes will do. Bleed the radiator, and top it off. Now you’re done.
Frequently Asked Questions
Question: How much does it cost to replace the water pump gasket myself?
Answer: Replacing a water pump gasket yourself, requires no costs other than the new gasket, along with any tools you may need. Costs will vary, but gaskets range from $6 to $20 depending on your model of Tacoma and the motor, while the water pump costs around $85. Not counting labor, you can replace it yourself for the price of an afternoon and the parts, but if you take it to a shop, you are looking at $250 to $500 depending on labor, parts, and which shop you visit.
Question: Should I replace my timing belt along with a water pump and gasket?
Answer: If you are replacing the water pump gasket, and you do not know the last time it was changed during the lifetime of the vehicle, then consider changing the timing belt and water pump too. Now, this only really applies to V6 Tacoma’s from 1994-2005, because the water pump is driven by the timing belt.
Therefore, if there is a water pump issue, it can compromise the timing belt and cost you an engine as opposed to a gasket.
Once you have the car apart enough to get to the timing belt, then changing it, the water pump and pump gasket is relatively easy, and timing belts are cheap as well: around $35 for a timing belt at Autozone. You do not have to replace the timing belt along with the water pump, but it is good preventative maintenance to do one with the other.
Question: How long will my replacement water pump gasket last?
Answer: If you keep up on your maintenance, then your water pump and gaskets will last for around 100,000 miles on average. Of course, many Tacomas are known to go for much longer periods; 100,000 miles is simply an average time period for a water pump and gasket to last.
Question: Should I replace my thermostat along with a water pump/pump gasket?
Answer: You do not explicitly need to change the thermostat along with a water pump or pump gasket. However, since the thermostat, at least on the V6 Tacomas, needs to be removed to access the water pump, you may as well replace it; it is not expensive.
The list of parts gets quite long once you start replacing them, but it is enough trouble to take everything apart in order to reach the water pump; you may as well do enough preventative maintenance down there, that you do not have to do it again for a long time.
Question: Will it void the warranty if I replace the water pump gasket myself?
Answer: If your Tacoma is new enough that the water pump gasket needs to be replaced, and it is still under warranty, then have the dealer do it, for peace of mind and service records in writing. However, if you are driving the truck and it is out of warranty, replace it yourself; it will not affect it in any way.
Changing a water pump is not a difficult job, although having to remove the timing cover and retime the engine makes it a little tougher and more intimidating. Still, it is not impossible, and hopefully, this article makes it possible for you.