# Question about Timing belt - locking the cam



## NUMBER2 (May 23, 2019)

As long as you line up the timing marks on the high pressure pump, cam sprocket, and crank sprocket, it doesn't really matter. When I replaced my belt a few months ago, I didn't use the tool or anything special like that. I rotated the engine over until the 3 timing marks were such that the new belt could easily be installed, (crank in the TDC location) and that was it. The cams are geared together at the other end of the head, so they will always be timed together, as long as you get the belt on right with the other 2 sprockets.

The belt has 3 timing marks on it. Two on the teeth, and one in the valley (or vise versa can't remember). The point is that as long as align it, you can't screw it up. Easy. My first try I did everything including tensioner and water pump, coolant drain and fill, in 2 hours. It seems intimidating, but it is the easiest timing belt you'll probably ever replace.

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## baked potato (Dec 27, 2019)

Thanks that's good to know, it will also be the 1st timing belt I've ever replaced


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## snowwy66 (Nov 5, 2017)

Techincally speaking. It doesn't really matter. It's not the piston that determines the stroke it's on. All it does is goes up and down. 

It's the valves that determine the stroke. As long as the 2 cams are lined up together and lined up with the piston. That's what matters.


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## Maqcro1 (Apr 29, 2019)

It’s been a few years since I did my belt but if I remember there was a timing mark on the crank pulley or just pull cyl 1 spark plug and see when the piston reaches the highest point. also the camshaft marks aren’t supposed to like up, the front cam mark is supposed to be lower than the rear cam.


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## snowwy66 (Nov 5, 2017)

Easiest thing to do is mark the gears together before disassembly. Maybe use a ruler to ensure a straight line marking. Using a dab of paint to make a spot.

Or, if possible. Dab a spot of paint on the gears AND the engine next to the gears. Align the paint spots with the gears.


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## boraz (Aug 29, 2013)

Maqcro1 said:


> It’s been a few years since I did my belt but if I remember there was a timing mark on the crank pulley or just pull cyl 1 spark plug and see when the piston reaches the highest point. also the camshaft marks aren’t supposed to like up, the front cam mark is supposed to be lower than the rear cam.


his cylinder 1 doesnt have a spark plug


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## boraz (Aug 29, 2013)

the tool is silly because you have to remove it to install the belt anyways

installing the belt is the only time the stuff is gonna move


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## snowwy66 (Nov 5, 2017)

You going to have a hard time with piston at highest point. 

Highest point occurs roughly 10 degrees BEFORE and AFTER TDC. That's 20* variance. You might make it when it's all aligned. You might not. Might be off a tooth on the crankshaft.


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## Maqcro1 (Apr 29, 2019)

TDC is still at 0* when the piston reaches the top. Spark will ignite around 10* BTDC just before the piston reaches the top pushing the piston back down.

If you don’t feel comfortable just use some paint like someone else here has suggested


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## NUMBER2 (May 23, 2019)

There are marks on all three sprockets and matching marks on the belt. If you line up the three marks on each, you cannot screw it up. 

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## baked potato (Dec 27, 2019)

thank you for the replies, i really appreciate the advice. i ordered the parts and i'm ready to tackle this project


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## TheRealHip (Sep 1, 2014)

There are a couple of really good videos on youtube on this.


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## boraz (Aug 29, 2013)

Maqcro1 said:


> TDC is still at 0* when the piston reaches the top. Spark will ignite around 10* BTDC just before the piston reaches the top pushing the piston back down.
> 
> If you don’t feel comfortable just use some paint like someone else here has suggested


SPARK???
are you high?


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## Maqcro1 (Apr 29, 2019)

boraz said:


> SPARK???
> are you high?


Umm yeah spark needs to happen before the piston reaches TDC. I’m not sure what the confusion is here.


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## Maqcro1 (Apr 29, 2019)

baked potato said:


> thank you for the replies, i really appreciate the advice. i ordered the parts and i'm ready to tackle this project


Sounds good. Let us know how it goes. If you get stuck on anything there are many people on here with the knowledge and experience to assist.


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## 15cruzediesel (Sep 30, 2019)

Maqcro1 said:


> Umm yeah spark needs to happen before the piston reaches TDC. I’m not sure what the confusion is here.


You do realize diesel engines don't ignite the fuel by spark, ever.

Approximately 2 degrees before TDC atomized fuel is injected into the cylinder, mixed with air and then it ignites at some point due to the temperature of the combined mixture being compressed. 

When the temperature reaches the ignition temperature of the fuel it goes bang.


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## plano-doug (Jul 1, 2015)

Maqcro1 said:


> Umm yeah spark needs to happen before the piston reaches TDC. I’m not sure what the confusion is here.


Boraz is teasing you. We're in a diesel sub-forum. But it's easy to lose track of that sometimes. 

Regardless, whether it's spark or injection, one of them will happen a little bit before TDC  

Doug

.


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## Maqcro1 (Apr 29, 2019)

plano-doug said:


> Boraz is teasing you. We're in a diesel sub-forum. But it's easy to lose track of that sometimes.
> 
> Regardless, whether it's spark or injection, one of them will happen a little bit before TDC
> 
> ...


thanks Doug, now that I look back at the top it is diesel gen 1.


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## BDCCruze (Jul 12, 2017)

I used the tool for piece of mind. It was $40 and even with that tool I saved over $500 doing it myself.



boraz said:


> the tool is silly because you have to remove it to install the belt anyways
> 
> installing the belt is the only time the stuff is gonna move


Well, the cam lock you don't remove, only the crank lock. However, you only have it removed after the tension is released and prior to re-tensioning it. You only take it off to remove the lose belt and are suppose to reattach it before routing the belt and setting tension, which does pull on everything. I had a little issue getting the belt equally going up each side of the crank which made the mark alignment harder on the cam. I'm glad I had the locks because it gave me the freedom to move it around confidently until I got it.

I'm happy that the guys that didn't use the tool were able to get it without issues but one wrong move and the motor is toast. I'm willing to gamble to save $500 but not to save $40.


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## plano-doug (Jul 1, 2015)

BDCCruze said:


> I used the tool for piece of mind. It was $40 and even with that tool I saved over $500 doing it myself.


Never start a project unless you can get some new tools out of it    

Seriously, when you run the numbers for a DIY repair, after the parts and tool costs, there's still usually substantial savings to be had, as your numbers show. It's not hard to justify the ~20 bucks I spent on the cam and crank locking tools for my 1.8 LUW when I replaced its timing belt.

Plus, my daughter also has a 1.8 LUW which will need a timing belt in the next ~24 months, so I'll get more use out of the tool.

Doug

.


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## e-iowa-o (Sep 2, 2015)

I watched the videos and used the locking tools. I appreciated the peace of mind, too. It's nice knowing everything is exactly where it is supposed to be when you line up the marks on the belt.


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