Can anyone tell me how far below the surface of the deck the piston is when it is at TDC?
I am doing a head gasket job on my F-150 5.4 motor. Before pulling the heads, I checked and re-checked that my timing marks were lined up. When I pulled the heads off, I noticed the #1 piston is about .050" below the surface of the deck. I went back underneath and looked at the timing mark on the timing chain sprocket and it appears to be at 6:00 but there is not a corresponding mark on the oil pan to line up the mark on the sprocket with.

I used a speed square off of the oil pan and "adjusted" slightly, the crank position to make sure the mark is dead on 6:00.

I was thinking that if someone knew what the actual distance was from the surface of the deck down to the piston when it is at TDC, I can be sure to get my marks all lined up again when I go back together with all of this, this coming weekend.



Richard

 

It should be virtually even. But it doesn't matter. The definition of TDC is that the crankshaft lobe is in line with the piston rod, and on the same side as that cylinder. So to check, just rock the crankshaft back & forth while watching the piston. Find the crank position that brings the piston as high as it'll go (TOP, Dead Center).

 

a few centimeters. Not totally even with the deck but a few hairs short of it. There is no corresponding mark. You take your chains and mark them like this.

Your crank gear should look like this.



Put the KEYWAY on the CRANKSHAFT at 12 oclock, this is "safe mode" It doesnt matter about the distance from the deck just DONT try this on TDC or your going to bend valves if you slip the chain and fail to put it on.

Ok so now you got the chains marked like the picture above? Put the SINGLE link on the tooth on the crankshaft gear that correspones with the "punch" or "dimple". Do the LEFT side first, or "driver" side. Put the Side with 2 marked links on the CAM GEAR, 1 tooth on the CAM GEAR itself will fall in place right between the TWO links.

 

My crank shaft sprocket does not look like that one pictured as far as the marks goes. Mine has a "cutout" just below the teeth. When I took it all apart, I set the mark on the crank pulley at the TDC mark on the timing cover (on the compression stroke).
After I pulled everything off and had another look, the piston was not dead even to the deck. It is about .050" lower than the deck height. I know it is not going to be even with the deck as the factory does not make it that "tight" for safe reasons. Right now, my keyway on the crank is at the 10:00 position, the heads are off and dis-assembled and I am picking them up from the machine shop today (had to get them re-surfaced, valve job and new valve stem seals and valve guides installed).

Everyone talked about the timing chains having 2 "off-colored" links that you are supposed to use when re-setting the timing. I have inspected both chains very carefully and there is definitely NOT 2 off-colored links. The links are all identical. I can "fold" the chain in half like you pictured and have 1 link that is left over, is that the one I am supposed to go by?

I also read that the timing marks on the cam sprockets are at 90* off of the head surface and I did check that with a speed square, prior to pulling the heads.

Any more help would be greatly appreciated. I don't have a home computer anymore (mother board crashed) so I am stuck trying to get all my answers before I leave work today at 5:00.



Richard

 

When you are installing or removing the chains you set the crank gear keyway at the 12 o'clock position with #1 piston at TDC on the compression stroke. you then turn it counterclockwise till the keyway is about at the 11 o'clock position. That dot should be at the 6 o'clock position. That is the safe mode and it will allow the camshaft to move the valves without hitting a piston. You then remove and reinstall the heads safely regardless of there the cam shaft is. This will allow you to turn the camshafts to their respective setup positions when you install different heads.

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Frod, a few millimeters maybe but not a few centimeters. That would be more than an inch.

 

.120" to be exact....at TDC

 

So 3.04 millimeters then.

 

Thought this might be helpful! These guys know their modular stuff!

http://www.modularheadshop.com/Artic...m%20degree.htm

 

I am at this point now. The keyway is at about 10:00 or so, the mark on the crank sprocket is at 6:00 right now.
Over the weekend, I got the heads mounted and torqued and am in the process of installing the cam again on the drivers side. I have the mark on the cam sprocket at 90* off the head surface (using a speed square) and am needing an in/lbs torque wrench to tighten the cam bearing caps to the head.

I also looked over both chains really well and there is definitely no "off color links" on my chains. That is the next step I have to figure out......



Richard

 

Send me a PM with your e-mail and I can send you a pdf file of the assembly instructions.

Regards

Jean Marc Chartier

 

SMN is down right now, but when they reappear, click the tan CV in my signature & look in the Diagrams album. A few rows down, you'll find a series of pics showing the timing marks, how to set the timing chains, & some other engine stuff.

 

O.K...., I have read everything you guys have linked me to and I am still confused.
In the link provided by derrick929, is a picture showing the front of a 4.6 with the cams in time. Everything I have read, says to set the mark on the cam at 90* off of the head surface. Clearly, in the picture, the drivers side cam mark is not 90* to the head. It might be 90* to horizontal, but not the head.
I have a 5.4 Windsor and the picture is a 4.6. The article even says the 5.4 is slightly different the way the chains locate, but is this what mine should look like?

Can anyone clarify this for me?


Steve83....thanks for the pics and diagrams but that goes right in line with what I was just asking. In your diagrams, it shows both cam marks at 90* to the head surface. In that picture I am asking baout from derrick929's link, it is not 90* off the head. Is that something specific to that 4.6 motor? I wouldn't think so as your CV also had a 4.6L?







Richard

 

It is not the camshaft mark that is 90° to the head surface. On the 4.6 engines it is the keyway that is 90°to the head.

5.4 procedure With the crankshaft keyway still at the 12 o'clock position you turn the left (driver side) camshaft till the timing mark is at approximately the 12o'clock position. Then you turn the right Cam till its timing mark is at approximately the 11o'clock position. After that you turn the Crank till the keyway is at approximately the 10:30 position and install the chains.

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Thank you very much for the PDF file. The PDF says it is for a 1997 F-150/250 5.4 engine. Was that engine a Windsor or Romeo? Reason I ask is one of the pages where it shows the torque specs and tightening sequence for the cam retaining caps/bolts says to tighten them, in sequence, to 27-32ft/lbs and then rotate them 85*- 95* and then rotate them again another 85* - 95*. It also shows 10 bolts per head (5 caps with 2 bolts each) while my motor has 13 bolts (5 caps with 2 bolts each and 1 more cap that has 3 bolts). Big difference.

Assuming this PDF was for a Romeo, would the timing procedure be the same?





Richard