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Timing Belt -- I let the cam pulleys slip -- Oh Crap
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Author:  mrt-mt [ Sat Feb 27, 2016 9:50 pm ]
Post subject:  Timing Belt -- I let the cam pulleys slip -- Oh Crap
OK, I can hear it now. Can't you RTFM. Obviously not or I wouldn't be posting. I deserve what I have coming to me. OK maybe I should duck.

So here is what I did. I decided to loosen the cam shaft sprocket bolts prior to installing the cam locking pins so I didn't have to worry about shearing them off. Well little did I know that the cam shaft sprockets are not keyed as some of the photos seemed to indicate and can spin free once the bolts are loosened. I noticed this as I tried to rotate the engine by turning the crank shaft bolt and after going thru a compression stroke it came to a dead stop. I looked thru the oil filler hole and notice the cam is not turning thereby confirming my suspensions that the piston was coming into contact with the valves. I did not exert any pressure as I immediately knew I screwed up.

OK so nothing is damaged at this point, just not timed. The belt is still on but the camshaft bolts are loose.

Can I turn the crank to TCD then rotate 90 degrees clockwise and install the crank locking pin then attempt to install the cam shaft locking pins by rotating the camshaft slight back and forth until the locking pins find the detent or doe a detent even exist in such a fashion that I could even determine if it was correct.

I should have been more careful. :banghead:

Can someone detail a procedure that can get me back on track.

Thanks in advance for any insight you can offer.
Author:  Hexus [ Sun Feb 28, 2016 12:15 am ]
Post subject:  Re: Timing Belt -- I let the cam pulleys slip -- Oh Crap
The only way I can think to do it now would require removing the intake. Maybe Geordi or someone else has another idea.

Best of luck to you man!
Author:  geordi [ Sun Feb 28, 2016 12:19 am ]
Post subject:  Re: Timing Belt -- I let the cam pulleys slip -- Oh Crap
Ok... Breathe. You are doing this by hand, so unless you are a gorilla, you are correct - there shouldn't be any damage at all.

First things first: Remove the timing belt entirely. I don't know why you were loosening it in the first place, but just take it out now.

Then take out the cam pulleys.

The "keyways" (which aren't) on the cams need to point at each other. You need to rotate the crank counter-clockwise a little bit to give yourself the clearance to do this, but after you have removed the pulleys, put the bolts back in, all the way to the cams. Don't tighten them, just finger tight.

Now, use the bolt and and the appropriate 17mm socket and wrench to rotate the cams clockwise at least one full revolution. You can turn them all day long if you want, you won't hurt anything. When you get tired of that fun, stop them with the intake keyway at the 9 o'clock position, and then turn it just a bit more until it "settles" in the next valley between lobes. You'll discover what I mean real fast. Do the same for the exhaust cam, but the keyway should be paused at the 3 o'clock position and then settle around 4-5.

The cams are now settled and the valves are all closed. NOW you can rotate the crank by hand clockwise, until you see the small timing divot in the crankshaft hub (near the center of the crankshaft below the bolt hole) and that is TDC on #1. Turn it to the 3 o'clock position and stop with the bolt holes perfectly vertical and horizontal.

THE CRANK IS NOW IN TIME.

Now go back to the cams and rotate them again clockwise until the respective keyway is pointing directly at the other one, and insert the pins. The cams are now in time.

There is a timing mark on the fuel pump pulley on the tapered shoulder at the inside edge of the pulley. This mates with a mark just under the bolt at the 8 o'clock position. Set the fuel pump there. The fuel pump is now in time.

When you are tightening up the cam pulleys, use a counter-hold bar and just compensate for your own force to set the pulley bolts at 80 lb-ft, WITH THE PINS IN PLACE. If you are doing this correctly, the pins should never feel any pressure against them at all.
Author:  flman [ Mon Feb 29, 2016 7:58 am ]
Post subject:  Re: Timing Belt -- I let the cam pulleys slip -- Oh Crap
If for some reason you still can not get the engine to rotate towards the 3 oclock mark without hitting a valve. You could loosen the bolts to the injectors, and valve cover, let the valve springs push it up, then rotate the crank. There is a chance that you might need to pull the injectors and install new crush washers and orings?
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