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- Joined
- Apr 3, 2019
- Messages
- 960
- Points
- 601
- City
- Florida
- Vehicle Year
- 2011
- Engine
- 4.0 V6
- Transmission
- Automatic
I finished changing out the timing chain tensioners today. Minor issues for me were having to take the entire wheel well cover off as well as pulling more hoses from the top than expected and the drain valve at the bottom of the radiator didn't work.
I did leave the bottom of the aluminum thermostat housing on as I did the job. (I stuffed the opening with paper towels to keep debris out.) The cover uses 10mm screws instead of 8mm for the OEM one.
The big problem was trying to tighten the top tensioner. I was able to crack the upper tensioner loose with a 27mm Combo wrench, but when I tried to use it to tighten the new one down, it kept slipping. The "handle" part between the ends was just too wide and kept hitting components. (It's a Craftsman, just in case anyone's curious) I looked online for possibly a ratcheting wrench hybrid that looked kinda like a socket but all I found was a 27/24mm one that was closed in the middle. I also thought of cutting a stubby socket and having a coworker weld a "stick" on it. Luckily, the next day I tried a medium adjustable wrench, and it worked. I cranked it down as hard as I could, hoping it would be near the 40 psi needed.
Putting everything back together went pretty easy. The 90 degree hose was the only sticking point.
I made sure to use the amazing trade secret found here of pressing down on the accelerator while turning the key. (For those that didn't catch this great tip. Doing this cranks the engine without starting it or running it. This primes the tensioners, so you don't have to fight to thread them in and risk cross threading! I heard that 15 seconds is enough time, but I played it safe and did two cranks at ten seconds followed by a third at five.)
The embarrassing part was that somewhere along the way I lost the radiator cap. In my focus on what I was doing, I set the thing on the engine. When I lowered the hood for dinner I heard something "big" clunk around as it fell into the engine bay. At first, I thought it had fallen into the drain pan, but no. Not there. I looked all around the engine and on the ground but found nothing. I'm thinking it fell in that weird pace between the plastic intake manifold and the engine block. (I found a bird's nest there! How is that possible? I drive the thing daily! How has this thing not caught fire?) I know that it's not in the way of anything super important like a carburetor or fan but still! Ugh! (I did try to find it with a magnet but didn't find anything.)
The other downside is that my A/C isn't working. I knew it was going as I would top it off with freon but this time it didn't work. The pully did turn but the fan did not blow. This prevented the antifreeze to circulate and there is at least a quart or two in the bucket. I hate the idea of an air bubble in the cooling system. Hopefully it clears in the overflow tank.
In the end I got the goal done. I changed out the tensioners like I wanted. The engine runs smooth too! No rattles at start up at all. That I'm happy with. Especially the fact that I hopefully extended the life of the engine another 70,000 miles. It's the stupid mistake and not being able to put all the antifreeze back that annoy me.
I did leave the bottom of the aluminum thermostat housing on as I did the job. (I stuffed the opening with paper towels to keep debris out.) The cover uses 10mm screws instead of 8mm for the OEM one.
The big problem was trying to tighten the top tensioner. I was able to crack the upper tensioner loose with a 27mm Combo wrench, but when I tried to use it to tighten the new one down, it kept slipping. The "handle" part between the ends was just too wide and kept hitting components. (It's a Craftsman, just in case anyone's curious) I looked online for possibly a ratcheting wrench hybrid that looked kinda like a socket but all I found was a 27/24mm one that was closed in the middle. I also thought of cutting a stubby socket and having a coworker weld a "stick" on it. Luckily, the next day I tried a medium adjustable wrench, and it worked. I cranked it down as hard as I could, hoping it would be near the 40 psi needed.
Putting everything back together went pretty easy. The 90 degree hose was the only sticking point.
I made sure to use the amazing trade secret found here of pressing down on the accelerator while turning the key. (For those that didn't catch this great tip. Doing this cranks the engine without starting it or running it. This primes the tensioners, so you don't have to fight to thread them in and risk cross threading! I heard that 15 seconds is enough time, but I played it safe and did two cranks at ten seconds followed by a third at five.)
The embarrassing part was that somewhere along the way I lost the radiator cap. In my focus on what I was doing, I set the thing on the engine. When I lowered the hood for dinner I heard something "big" clunk around as it fell into the engine bay. At first, I thought it had fallen into the drain pan, but no. Not there. I looked all around the engine and on the ground but found nothing. I'm thinking it fell in that weird pace between the plastic intake manifold and the engine block. (I found a bird's nest there! How is that possible? I drive the thing daily! How has this thing not caught fire?) I know that it's not in the way of anything super important like a carburetor or fan but still! Ugh! (I did try to find it with a magnet but didn't find anything.)
The other downside is that my A/C isn't working. I knew it was going as I would top it off with freon but this time it didn't work. The pully did turn but the fan did not blow. This prevented the antifreeze to circulate and there is at least a quart or two in the bucket. I hate the idea of an air bubble in the cooling system. Hopefully it clears in the overflow tank.
In the end I got the goal done. I changed out the tensioners like I wanted. The engine runs smooth too! No rattles at start up at all. That I'm happy with. Especially the fact that I hopefully extended the life of the engine another 70,000 miles. It's the stupid mistake and not being able to put all the antifreeze back that annoy me.
