Camshaft installation 5VZ-FE
Hello everyone.
I've been a frequent visitor of this board to look for inspiration to solve the problem of the day, and now it's time to pay my debt to the Toyota Community, so I registered and here's my first post I wrench a lot on 92-99 Camrys - timing belts, engine and transmission swaps etc. Today I had a 98 4Runner in my shop, in need of a new timing belt. It took me less than 2 hours to do that job. I've seen quite a few posts of frustrated DIY wrenchers so I thought I'd pass along a few tips.
Before I get started on the timing belt process (which I will put in a second post), I'd like to pass along a few tips about cams. Specifically, the process of installing and timing them. I've seen a lot of posts from people confused about the whole one dot versus two dot alignment process.
First, lets clarify left versus right bank. Very confusing. the RIGHT bank will be on your left hand side (passenger side) if you are standing in front of the engine. These cars have one camshaft position sensor, on the right bank/passenger side. The right camshaft sprocket has a little metal stab sticking out of it, which tells the camshaft position sensor where the camshaft is at. That sprocket has an R stamped in it. The left side doesn't have a camshaft sensor and its sprocket (with L stamped in it) doesn't have that tab. So if you can't remember left or right, locate the camshaft position sensor and look at the letter stamped in the sprocket.
The left and right side cams are not interchangeable. This means you just can not screw that up - there is only one way to get the 4 cams onto the 2 heads. They simply won't fit any other way. So that's easy enough.
The FSM, and several other books, will tell you that you have to align the right side cams on "2 dots" and the left side cams on the "1 dot". There are countless posts out there about people doing that and then noticing the timing belt mark on one side is off by 180 degrees. Some say the manuals are wrong. I'm going to try and demystify this.
What I find downright stupid is that Toyota put these alignment dots on the back side of the camshaft sprockets. Really, you guys couldn't put dots on both sides of these gears? You will be climbing on top of your engine with your head against the hood, with a flashlight, to see these #@$%^& dots. Do yourself a favor and make your own marks on the front side of the sprockets with white touch-up paint.
Some posts say manuals are wrong and you line them up 1-dot to 1-dot on both banks. It doesn't matter. You can line both left and right bank up 1-dot to 1-dot, or 2-dot to 2-dot, or do one bank 1-dot to 1-dot and the other bank 2-dot to 2-dot. If you look closely at the cams, you'll notice that the 1-dot is 180 degrees (half a turn) away from the 2-dot. So if you have your cams lined up 1-dot to 1 dot, they will also be lined up 2-dot to 2-dot, if you turn the cam 180 degrees. So why does the FSM have you alight the right bank on the 2 dots and the left bank on the 1 dots? Because it allows you to install the cams without pressing down any valves in the process.
Two things you do not want to do. One, do not align 1-dot to 2 dot. Two, do not install cams and torque down cam bearing caps in such a way that you depress any valves in the process.
Let's start on the right bank, passenger side. Start with the intake cam. Apply assembly lube, or at least a good helping of oil, on the cam and bearings. Drop the exhaust cam in as straight as you can with the 2 dots pointing pretty much straight up, more or less aligned with the spark plug tubes. All of the cam lobes should be "free", meaning none should be pointed down and touch valves. The cam should lay on all of the bottom bearings, completely seated. No pushing, no torquing. Drop it down as straight as you can so it doesn't bind in any way. If you get it right, you turn the cam a few degrees either way, without lifting it up and without making lobes hit valve tappets. More lube, now put on the caps and torque them to spec, see the FSM for torque specs and sequence. One down.
Here comes the trick. Bear with me. Now grab the right side exhaust valve, locate the 2 dots on the gear and position it ON TOP of the intake cam sprocket, aligning the 2 dots to the 2 dots. Do not dis-engage the gears and simply roll the exhaust cam over the gears into position. This is a LOT easier than trying to drop the exhaust cam directly in place and then spend oodles of time counting gear teeth and turning cams to make sure you have the dots lined up right. Remember, the intake cams dots are still pointing straight up, and to ensure you have dots to dots, you would need to turn cams so the teeth with the dots mesh. Don't do that. Line them up "in the air", roll the exhaust cam over the gears into place, drop it onto its bearings gently and straight. Do this and you will find none of the exhaust cam lobes are pushing in valves either, and that is what you want when you put the caps on: NO VALVE PUSHING! Oil or lube well, install the exhaust cam caps and torque them to spec. Once you have both cams installed, put the sprocket on and torque the sprocket bolt to spec (hold the intake cam with a 24 mm wrench). Now you double check the alignment by turning the cam using a 17mm wrench on the sprocket bolt. Turn them and make sure the 2 dots mesh with the 2 dots. You will be pushing in valves when you do this. Keep turning and you will see that 1 dot will align with 1 dot, half a turn later. See? It doesn't matter if you do 1 to 1 or 2 to 2.
The process on the left side is the same. Intake first, but now point the 1 dot straight up instead of the 2 dots. Make sure the cam is free. Put the caps on. Alight exhaust cam "in the air" on top of the intake cam, 1-dot to 1-dot, roll her down into position. Put caps on, put sprocket on, turn cams and check that the dots mesh.
Remember: Never put cams in with force and never put caps on in such a way that you are pushing in valves.
I've read posts from people who did the 2-dot to 2-dot thing on the right and 1-dot to 1-dot on the left and then found the TB mark off by 180 degrees on one of the sprockets. Let me clarify that issue as well while I'm at it. The long and short of it is this: the whole dot business is just to get the intake and exhaust cams timed correctly relative to each other. Has nothing to do with TB timing and TB marks. Yes, if you line up 2-dot to 2-dot and then look at the TB mark on your sprocket, it will point down. Once you get the cams in and dots lined up and you get ready for the TB, just forget about the dots.
I will tell you this though. Turn the cams so the TB marks on both left and right cam sprocket line up with marks the back plate. Now crawl back up on the engine and look at your cam dots. You should see 1-dot aligned to 1-dot on both left and right bank. This is why some people say to time the cams on both banks 1-dot to 1-dot. So why does the FSM have you do 2-dot to 2-dot on the right and 1-dot to 1-dot on the left? Because it allows you to drop in the cams without pushing in any valves...
There is no way to install cams without pushing in valves and have dots aligned (meshed) at the same time. You point the dots up, put the cams in "free", put the caps on and then you turn them so they mesh and you can check dot-meets-dot.
Hope this helps.
Next post: how to install a TB in 2 hours ( I did it in 1:35...)
P.S. No whining that this post is so long. I'm trying to help you. If it's too much to read for you, don't read it!
Hello everyone.
I've been a frequent visitor of this board to look for inspiration to solve the problem of the day, and now it's time to pay my debt to the Toyota Community, so I registered and here's my first post I wrench a lot on 92-99 Camrys - timing belts, engine and transmission swaps etc. Today I had a 98 4Runner in my shop, in need of a new timing belt. It took me less than 2 hours to do that job. I've seen quite a few posts of frustrated DIY wrenchers so I thought I'd pass along a few tips.
Before I get started on the timing belt process (which I will put in a second post), I'd like to pass along a few tips about cams. Specifically, the process of installing and timing them. I've seen a lot of posts from people confused about the whole one dot versus two dot alignment process.
First, lets clarify left versus right bank. Very confusing. the RIGHT bank will be on your left hand side (passenger side) if you are standing in front of the engine. These cars have one camshaft position sensor, on the right bank/passenger side. The right camshaft sprocket has a little metal stab sticking out of it, which tells the camshaft position sensor where the camshaft is at. That sprocket has an R stamped in it. The left side doesn't have a camshaft sensor and its sprocket (with L stamped in it) doesn't have that tab. So if you can't remember left or right, locate the camshaft position sensor and look at the letter stamped in the sprocket.
The left and right side cams are not interchangeable. This means you just can not screw that up - there is only one way to get the 4 cams onto the 2 heads. They simply won't fit any other way. So that's easy enough.
The FSM, and several other books, will tell you that you have to align the right side cams on "2 dots" and the left side cams on the "1 dot". There are countless posts out there about people doing that and then noticing the timing belt mark on one side is off by 180 degrees. Some say the manuals are wrong. I'm going to try and demystify this.
What I find downright stupid is that Toyota put these alignment dots on the back side of the camshaft sprockets. Really, you guys couldn't put dots on both sides of these gears? You will be climbing on top of your engine with your head against the hood, with a flashlight, to see these #@$%^& dots. Do yourself a favor and make your own marks on the front side of the sprockets with white touch-up paint.
Some posts say manuals are wrong and you line them up 1-dot to 1-dot on both banks. It doesn't matter. You can line both left and right bank up 1-dot to 1-dot, or 2-dot to 2-dot, or do one bank 1-dot to 1-dot and the other bank 2-dot to 2-dot. If you look closely at the cams, you'll notice that the 1-dot is 180 degrees (half a turn) away from the 2-dot. So if you have your cams lined up 1-dot to 1 dot, they will also be lined up 2-dot to 2-dot, if you turn the cam 180 degrees. So why does the FSM have you alight the right bank on the 2 dots and the left bank on the 1 dots? Because it allows you to install the cams without pressing down any valves in the process.
Two things you do not want to do. One, do not align 1-dot to 2 dot. Two, do not install cams and torque down cam bearing caps in such a way that you depress any valves in the process.
Let's start on the right bank, passenger side. Start with the intake cam. Apply assembly lube, or at least a good helping of oil, on the cam and bearings. Drop the exhaust cam in as straight as you can with the 2 dots pointing pretty much straight up, more or less aligned with the spark plug tubes. All of the cam lobes should be "free", meaning none should be pointed down and touch valves. The cam should lay on all of the bottom bearings, completely seated. No pushing, no torquing. Drop it down as straight as you can so it doesn't bind in any way. If you get it right, you turn the cam a few degrees either way, without lifting it up and without making lobes hit valve tappets. More lube, now put on the caps and torque them to spec, see the FSM for torque specs and sequence. One down.
Here comes the trick. Bear with me. Now grab the right side exhaust valve, locate the 2 dots on the gear and position it ON TOP of the intake cam sprocket, aligning the 2 dots to the 2 dots. Do not dis-engage the gears and simply roll the exhaust cam over the gears into position. This is a LOT easier than trying to drop the exhaust cam directly in place and then spend oodles of time counting gear teeth and turning cams to make sure you have the dots lined up right. Remember, the intake cams dots are still pointing straight up, and to ensure you have dots to dots, you would need to turn cams so the teeth with the dots mesh. Don't do that. Line them up "in the air", roll the exhaust cam over the gears into place, drop it onto its bearings gently and straight. Do this and you will find none of the exhaust cam lobes are pushing in valves either, and that is what you want when you put the caps on: NO VALVE PUSHING! Oil or lube well, install the exhaust cam caps and torque them to spec. Once you have both cams installed, put the sprocket on and torque the sprocket bolt to spec (hold the intake cam with a 24 mm wrench). Now you double check the alignment by turning the cam using a 17mm wrench on the sprocket bolt. Turn them and make sure the 2 dots mesh with the 2 dots. You will be pushing in valves when you do this. Keep turning and you will see that 1 dot will align with 1 dot, half a turn later. See? It doesn't matter if you do 1 to 1 or 2 to 2.
The process on the left side is the same. Intake first, but now point the 1 dot straight up instead of the 2 dots. Make sure the cam is free. Put the caps on. Alight exhaust cam "in the air" on top of the intake cam, 1-dot to 1-dot, roll her down into position. Put caps on, put sprocket on, turn cams and check that the dots mesh.
Remember: Never put cams in with force and never put caps on in such a way that you are pushing in valves.
I've read posts from people who did the 2-dot to 2-dot thing on the right and 1-dot to 1-dot on the left and then found the TB mark off by 180 degrees on one of the sprockets. Let me clarify that issue as well while I'm at it. The long and short of it is this: the whole dot business is just to get the intake and exhaust cams timed correctly relative to each other. Has nothing to do with TB timing and TB marks. Yes, if you line up 2-dot to 2-dot and then look at the TB mark on your sprocket, it will point down. Once you get the cams in and dots lined up and you get ready for the TB, just forget about the dots.
I will tell you this though. Turn the cams so the TB marks on both left and right cam sprocket line up with marks the back plate. Now crawl back up on the engine and look at your cam dots. You should see 1-dot aligned to 1-dot on both left and right bank. This is why some people say to time the cams on both banks 1-dot to 1-dot. So why does the FSM have you do 2-dot to 2-dot on the right and 1-dot to 1-dot on the left? Because it allows you to drop in the cams without pushing in any valves...
There is no way to install cams without pushing in valves and have dots aligned (meshed) at the same time. You point the dots up, put the cams in "free", put the caps on and then you turn them so they mesh and you can check dot-meets-dot.
Hope this helps.
Next post: how to install a TB in 2 hours ( I did it in 1:35...)
P.S. No whining that this post is so long. I'm trying to help you. If it's too much to read for you, don't read it!
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