Success, she runs! My boyfriend and I finally got around to replacing our timing chain. We bought a kit from Mizumo Auto on eBay with guides, sprockets, tensioners, and the three chains. I have a rapport with a local autoparts store, so we decided to perform the repair there. Best decision ever! Every day we needed some new tool or part or even just AAA batteries to move forward with the job, so it was great being right there at the store. We were near fast food venues too, which came in handy. We commuted by bus every day after work and eventually enlisted a friend to drive us to and from the 4runner.
This job took two weeks. The labor added up to 76 hours, and there were two of us. xD There’s a reason mechanics charge so much for this repair. HOWEVER, the thing is, we DID pay a mechanic to fix this (three times, technically, two different mechanics), and it didn’t fix the problem! And all three times they kept our money! The problem is, this job is quite complex, and, as some of you have pointed out in this forum, 2007 4Runners apparently had a bad batch of chains, so paying people to do this job and even to swap the engine out for a different used 2007 engine (couldn’t afford refurbished) didn’t do any good. Long sad story. We promised ourselves that if the third attempt at trusting a mechanic with our life savings didn’t work, we’d try it ourselves! And even though it took us 76 hours, because we went carefully and did everything to spec, the repair worked! And we got to learn so much about our car along the way.
It was kind of fun!
TIPS:
Everyone will go through this differently, I’m sure, but here’s what worked for us.
1. Read posts on this forum (particularly on this thread right here and on this other thread, particularly any post by Waypoint—thank you!), and watch this Youtube video. This one is helpful for setting the timing. This link is a handy read to. And, BUY THE SHOP MANUAL. It is an invaluable resource and has all the torque specs and pictures. It’s literally THE instruction manual for repairing your car.
2. No jack needed. I only used the handle for mine as a cheater bar.
3. Parts I bought on purpose: Mizumo Auto timing chain kit with guides, sprockets, and tensioners, water pump, GR-FE1 full gasket set (but only used oil pump o ring, crankshaft pulley seal, oil filter o ring, water pump o ring, RTF sealant for timing cover, valve cover gaskets, water pump triple gasket, timing chain piston inspection window gasket, head gasket, and ignition coil rubber boots), oil filter.
4. Ordinary tools we used: Ratchet and metric 6-sided socket set, extension bars, torque wrench, regular wrenches or inline wrenches, a few metric hex bits, pliers, needle nose pliers, rubber mallet, 2’ cheater bar (from my hydraulic jack), flathead screwdriver, razor, hand pump. Supplies: high mileage engine oil, coolant, a little automatic transmission fluid, Gunk heavy duty engine degreaser gel, Dawn soap, rinse water, scrub pads, old toothbrushes, wire brush, engine lube, nuts and bolts as needed, gasket glue, blue thread locker, painter’s tape, ziplock bags, permanent marker.
5. Special tools we bought: Immovable stripped bolts: PB Blaster penetrating oil, cold chisel and 3 lbs sledge hammer, Irwin stripped bolt remover sockets. Crankshaft pulley bolt: crankshaft bolt pulley holder, 22mm 6-sided socket, one cheap 1/2” driver breaker bar, one expensive extensible 1/2” breaker bar, one 4’ cheater bar (plain metal pipe of correct diameter, from Ace Hardware). Crankshaft pulley seal: seal puller (I can’t believe I’m buying this thing but I have to). Camshaft: premium 23mm straight-sided toothed wrench to hold the camshaft still for bolt removal for sprocket replacement, and for adjusting exhaust chains relative to main chain.
6. Crankshaft pulley bolt: We used the bolt holder and TWO breaker bars, one attached to the bolt holder and extended to the ground, and one attached to the pulley bolt with a 22mm 6-sided socket and operated using a 4’ cheater bar. Sprayed the bolt with PB Blaster a couple times, let it soak in, pushed down on the long cheater bar, and pop! It broke loose easily! We were pleasantly surprised. Of course, we literally spent $120 on tools and supplies to get that monster off. But it worked, and we were able to get it back on later!
7. The most irritating thing I bought was the seal puller for the crankshaft pulley seal. I feel like there must have been some way to get that thing off without ANOTHER special tool. But I didn’t want to damage anything around the seal, so I swallowed my pride and bought the stupid tool. Seal came off in 10 seconds.
8. Worst bolts (nuts, actually) were on the fan clutch for some reason. We had to hammer and chisel them off.
9. As we went along, we took pictures so we’d know how to put the car back together.
10. Whenever we took off a part, we taped the bolts in place on the part. This helped with reassembly so much! We also labeled which ignition coil was which in case that mattered. Any bolts we couldn’t immediately tape to the part (valve cover bolts, front timing cover bolts) were placed into labeled ziplock bags.
11. For some reason I tried to take off the drive belt tensioner pulley. DO NOT do this! And if you do, know that this special pulley bolt is a rightie loosie. I didn’t know this, broke it, and ended up breaking the darn bolt head off. I couldn’t find a replacement bolt and had to just replace the whole tensioner assembly. Dumb.
12. You do have to remove the whole tensioner assembly to get the front timing cover off (leave the pulley on!!!). Manual says “unbolt,” but we had to remove it before we could get the front timing cover to budge. Removing it also gave us access to a much-needed additional pry point.
13. We cleaned the front timing cover, the engine area behind the front timing cover (very carefully, and not too thoroughly), phasers (externally), and the valve covers. We did not touch the camshaft bays, even though they looked sludgy, because they looked too complicated and we didn’t want to cause more harm than good.
14. Top dead center: We took the spark plugs out to not have to fight compression. Then, with the crankshaft pulley bolt back in, we cranked the engine a million times, watching all the dots and marks and valves to get a feel for it. Then we put a garden flag in the #1 cylinder so we could just watch it go up and down. xD The silver cam lobes point at each other when the cylinder is up. There’s also a spring function that throws you forward or backward if you nudge off of that perfect spot. I don’t fully understand this, but that’s what we felt.
15. We figured out that our timing marks are all good, so we were able to rely on them.
That made lining up the new chain okay. It was still tricky, and we studied the diagram and counted links to make sure we had the colored links in the right places. Then we placed the color links onto the dotted sprocket teeth. Tensioners weren’t on yet, and idler sprocket was off. This gave us wiggle room. Having two sets of hands was AWESOME and made this task much easier than it would have been for one person. It still took us two tries though, because the first time we did it we were one tooth off on the crank sprocket (the hardest to see), so on turning the engine a few times to test our work, we saw our timing was off again. So we compressed the tensioners and put their pins in and lined up the links again, takin special care to line up the colored link on the crank sprocket’s dotted tooth. On turning the engine over again, several times, everything stayed lined up! Note that the colored links will move, but the sprocket dots and phaser marks and all that will all line up, and that’s what matters.
16. We soaked the chains in a little cup of engine oil and put engine lube on all new tensioners, sprockets, and chains.
17. Remove all old sealant (razor helps) and wipe away all oil before resealing! Then, as Waypoint advises, practice with several dry runs (and make sure you’ve put in your o rings with gasket glue!) before you put the sealant on for real. My boyfriend was better at placing the cover, so he did the honors.
18. We had thread locker just in case but only used it on the #1 timing chain tensioner bolts, just because ours felt a little loose.
19. When torquing the front timing cover bolts, we zigzagged and tightened gradually. On reaching final torque, I marked the bolt with a permanent marker to keep track.
20. The rest was easy! It was just a matter of following the manual in reverse, putting on new gaskets here and there, tightening to torque specs, putting all the obnoxious hoses on all the way… All done!
This job is not for the faint of heart. But, with some time on evenings and weekends, careful attention to the manual, a helper if you have one, and a hefty budget for all the unexpected tools, bolts, and other supplies you’ll need, you can pull this off and get it done right!
Turning that key, passing the emissions test, and sticking that legal registration sticker on to drive another day felt sooooooooo so good.
And now we have the pleasure of bragging to all our friends and family about our mechanical prowess and can maybe teach them a thing or two.
All in all, since we were able to get around via bicycle, public transit, and friends for the two weeks it took to finish the job, this was totally worth the time and effort!
PIC: New chains and sprockets on somewhat-cleaned engine, hooray!