It is Monday, 8:30 AM, temperature is 78 degrees with partial clouds.
I pull the Tacoma part way into my garage and get started.
Mileage: 339496
I am using an AISIN TKT-025 timing belt kit, which includes a water pump, both idlers, a tensioner, and of course a new belt.
I also purchased a Toyota thermostat 90916-03075, which claims to be a 180F (82C) thermostat. Both items were purchased on Amazon. -- Back in March of 2018, It has taken me 8 years to get around to installing them. Don't tell anyone.
When I say left or right, it is from the mechanics view, looking at the front of the vehicle. In other words "left" is the passenger side.
Drop skid plate. This involves 3 nuts up front and 4 bolts towards the back. All 12mm.
Drain coolant from radiator. This is going to take forever through the tiny hole at the bottom of the drain valve, so I just keep unscrewing the valve body until it come out and then I get results in a hurry! It makes a big mess -- it is not clear that this saves time.
Remove upper radiator hose.
Loosen fan shroud (four 10mm bolts). Two clips allow a lower part of the shroud to be removed, then it can be pulled up and out.
Consider taping a piece of cardboard in to protect the radiator.
Remove the fan. Four 12mm nuts hold the fan in place. If the pulley spins, use a pry bar to hold it while you loosen the nuts.
Remove the power steering belt. There are 2 bolts that lock it in place,
one on top and one below, both 14mm.
then an adjuster on the far left.
I turned the adjuster about "40 cranks" then realized that one of the
lock bolts was still tight.
The easy way to get the belt off once you release a bit of tension is
to pull the pulley that was behind the fan straight forward and off.
Belt is marked 4PK1070.
Next the A/C belt comes off. This has a tensioner pulley.
The pinch bolt is the one in the center of the pulley.
The adjuster is underneath and needs a lot of releasing as there
is no pulley to just pull off the front like the power steering.
Belt is marked 4PK870.
My alternator pulley just pulled off without releasing anything.
Belt is marked 4PK1050..
Release the clips holding 3 plug wires on top of the belt cover. Also release an electrical thing on the left (mine had already broken loose).
Remove the timing belt cover. It is held by six 10mm bolts.
Use a 19mm socket to rotate everything to TDC. Turn clockwise as viewed from the front. There are calibrated marks on the crankshaft as well as marks on both camshaft pulleys.
Remove the fan pivot. There is a long bolt on top and two nuts below. All 14mm. The left nut holds the power steering adjuster which you also remove. It is a good idea to clean and lube the adjuster.
NOW! Time to break the 19mm crank bolt loose. I have a chain wrench, but I can't figure out a way to use it without a helper. So I use the "starter bump" method. I have a 19mm impact socket and a 3/4 drive breaker bar with a 3/4 to 1/2 adapter.
Now we need to return the engine to TDC. The chain wrench is handy here.
Lucky me! With a bit of wiggling and prying, the harmonic balancer pulley assembly comes off without the need for a puller.
I am very careful not to damage the thing behind the pulley cluster. The timing belt rides on it, but it also has "teeth" that are sensed by a engine position sensor, and the teeth are easily damaged.
Remove the lower cover. Here we have four 10mm bolts identical to the ones in the upper cover. The bolt on the lower left has a thin metal piece (holding a wiring harness) blocking it, but a 10mm bolt can be removed on the right side of that wiring bracket thing that allows it to be pushed out of the way.
Remove (pull off) a giant "washer" on the crankshaft in front of the timing belt. Take note that the side with the slight bulge goes on towards the belt.
Now the point of no return. Remove the upper idler pulley. This is a 14mm. And now you can remove the belt.
Now remove the tensioner pulley assembly. This requires a special tool. A 10mm allen on a 3/8 drive socket base. Take care not to loose the washer behind this.
Now the hardest thing -- the rear bolt on the tensioner. People say you can manage this without removing the A/C compressor if you have a wobbly socket, but I could see no way to manage that. So I removed the compressor and bracket. Four 12mm bolts and the compressor is loose and can be sort of set to the side. Now it is an ugly business to get the bracket out of the way. You have 5 bolts to deal with. All 14mm. The easy one is a long one that comes in from the front. Two medium long ones are on the side on top. The hardest one is pretty much dead center on the side.
Install the tensioner (two 12mm bolts). The torque spec is 20 ft-lbs, but I don't have a torque wrench that could get in there.
Install the tensioner idler pulley. Don't forget the washer behind it. Torque is 26 ft-lbs.
Now I reassemble the A/C compressor that I removed.
Now you have choices. I chose to do the water pump next.
Remove the dipstick (to get to the bypass hole). A single 10mm bolt on the alternator, then it pulls out. It has an O-ring.
Remove the lower radiator hose. Be ready for a lot of coolant. I was ready, but then the coolant found a path along a frame member and gave me another mess to clean up when I wasn't watching.
Remove 3 bolts (12mm) and take off the themostat housing. (the piece that goes to the radiator.
Remove 7 bolts (12mm) that hold the water pump in place.
My old water pump was stuck in place and took a bit of hammering and prying to remove. No glue was found once it came off. The enginer block surface had a lot of scale and crud. More than a razor blade could clean off. I used an old wood chisel as a scraper, followed up by some razor blade scraping along with a wire brush on my dremel tool.
I put a thin coat of Toyota FIPG on the engine block surface, then the gasket, new water pump, and 7 bolts. The bolts are torques to 20 ft-lbs, as are the 3 nuts for the thermostat housing.
I wrap the gasket around the new themostat and it gets captured by the housing. Note that the thermostat has a breather hole that needs to get placed near the top.
Reinstall the bypass, lower radiator hose, and dipstick.
Now for the camshaft seals. I am not going to replace the crankshaft seals. Both pulleys need to come off first. They are marked L and R. R is the passenger side. This is a 17mmm bolt. The torque is 81 ft-lbs.
It looks like I won't be doing the camshaft seals either. Working alone, I am unable to break the bolt loose. I should have done this job when I was younger and stronger. The seals are not leaking, so maybe it is best to leave well enough alone?
Ensure that the cam gears are at TDC
Now for the belt. My belt has marks that make it easy to set it on the cam gears, and I have clips to hold it there.
The trick is finding the mark(s) on the crankshaft. In the back of it is a mark on the flat part. This should be straight up at TDC, which is good to verify, but of no use to line up my marked belt. There is a drilled "divot" on the front of the crankshaft pulley that marks a tooth. On my vehicle this was pointing straight to the right the rear mark is on TDC.
I leave the upper idler pulley out for last. I start at the bottom and get the belt onto the crank pulley with marks lined up. Then I work up to the top. I use a 17mm wrench to turn the cam slightly left or right to allow me to get the belt on with the marks lines up -- then put the cam back on TDC> Last of all I install the upper idler pulley. This actually goes on just fine (it is snug). It has a 14mm bolt and is torqued to 30 ft-lbs
Put any slack over the tensioner, and pull the pin!
Now reassembly begins. Put the washer on the crank, bulge towards the belt. Then the lower cover. Then the harmonic balancer (I put a little oil on so it will slide on easily). Then the bolt.
Now turn the engine a full rotation. Watch the timing marks on the crank and turn it to zero. Then check the marks on the cams. Ignore the markings on the belt. I check out OK.
Now to torque the crank bolt. I have a manual, so I put it into gear and shift into 4th gear. I take it 25 ft-lbs at a time. 100, 125, 150, ... The spec used to be 184, but Toyota updated it to 217 ft-lbs. It works! I get it to 217 ft-lbs without needing to fool with a chain wrench or get help. Hooray for manual transmissions!
Back together we go. As they say, reverse of disassembly
Fan idler and bracket Power steering adjuster. upper belt cover
Alternator belt. With the pulley loose, no need to fool with
the tensioner (I didn't touch it when I took the belt off).
Belt is marked 4PK1050..
After I get the alternator belt on, I put on the next pulley and then the four bolts to keep everything lined up.
Next the A/C belt
Belt is marked 4PK870.
Last the power steering belt.
Belt is marked 4PK1070.
Then on goes the fan.
Be sure to replace the shroud before installing the upper radiator hose.
Replace the upper radiator hose, fill with fresh coolant (or funky old coolant if you saved it) and you are done.
The big moment is starting the engine. Mine seemed to run at an unusually high RPM the first minute or so. Then it settled down.
If you have any extra nuts or bolts, just throw them away and don't tell anyone.
Tom's Tacoma pages / tom@mmto.org