Timing Marks on 98 Cobra (pics)

misterb

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Dec 3, 2004
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I'm a bit worried because the timing marks on my motor do not line up.

When the heads were installed, I wasn't around (done by respected NJ shop) and I was able to turn a 13.3 with a forged 302 (VT Engines) with FRPP cams, headers, underdrive pully, 4.10's.

Now I'm wondering what 1 tooth off would cause?
 

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With Ford's DOHC engines, 1 tooth off is the world!!

There is an old, but valuable article how some Cobra's were dynoing 10-30 more HP at the wheels. Get that fixed asap.
 
With Ford's DOHC engines, 1 tooth off is the world!!

There is an old, but valuable article how some Cobra's were dynoing 10-30 more HP at the wheels. Get that fixed asap.

Thanks- I thought that they would *always* line up, but that is not the case. I understand that one tooth off would mean a *really* lousy-running car. You must turn it over a few times to get it right.
 
timing marks?

hey this is funny.....i just had my engine apart and wondered the samething cause i never did an engine rebuild let alone on a modular...those copper links may or may not hit the marks..depends on if the tech did use them...i turned mine when it was on engine stand just to really find out,,,well a modular engine is different than normal...marks will line up but you need to turn crank like 8 times around instead of 2..you can mark the 2 cam sprockets with nail polish and mark the crank on outside on both pully and case for a reference,,than turn untill they all meet together..on the crank you will need to find the (tdc)top where keyway is and set that first as to set the pully at tdc before marking...if you mark just the pully opposite tdc and than keep turning and cams should show if they are out..SECTION 303-01C: Engine — Cobra 4.6L (4V) 2003 Mustang Workshop Manual
IN-VEHICLE REPAIR Procedure revision date: 06/14/2002

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Timing Drive Components Printable View (253 KB)

Special Tool(s) Holding Tool, Crankshaft
303-448 (T93P-6303-A)

Removal

CAUTION: Since the engine is not free-wheeling, if the crankshaft (6303) or the camshafts (6250) are moved in any manner during removal and installation, the crankshaft and the camshafts must be resynchronized.

Remove the engine front cover (6019). For additional information, refer to Engine Front Cover in this section.
Remove the crankshaft sensor ring from the crankshaft.

CAUTION: Unless otherwise instructed, at no time when the timing chains (6268) are removed and the cylinder heads (6049) are installed is the crankshaft (6303) or the camshaft (6250) to be rotated. Severe piston (6108) and valve damage will occur.

Using the special tool, position the crankshaft as shown.

CAUTION: The camshaft timing marks must be correctly lined up or damage to the valves and pistons can occur.

NOTE: The copper links on the timing chain may not line up with the timing marks on the sprockets.

Make sure the timing marks on the camshaft sprockets are correctly positioned. If necessary, turn the crankshaft one full turn clockwise to correctly position the sprockets.

NOTE: LH shown; RH similar.

Remove the two bolts, the timing chain tensioner (6L266) and tensioner arm (6L253).

CAUTION: Unless otherwise instructed, at no time when the timing chains are removed and the cylinder heads are installed is the crankshaft or the camshaft to be rotated. Severe piston and valve damage will occur.

Remove the LH and RH timing chains and the crankshaft sprocket (6306).
Remove the special tool from the crankshaft.
Remove the RH timing chain from camshaft sprocket.
Remove the RH timing chain from the crankshaft sprocket.
Remove the LH timing chain from the camshaft sprocket.
Remove the LH timing chain and crankshaft sprocket.

CAUTION: The bolts are different lengths and must be returned to their original location.

NOTE: RH shown; LH similar.

Remove the bolts and the timing chain guides (6K297).

Installation

CAUTION: Timing chain procedures must be followed exactly or damage to the pistons or valves will result.

Compress the tensioner plunger, using a soft-jawed vise.

Install a retaining clip on the tensioner to hold the plunger in during installation.
Remove the tensioner from the vise.

If the copper links are not visible, mark one link on one end and one link on the other end, and use as timing marks.

Install the timing chain guides.

Rotate the LH camshaft sprocket until the timing mark is approximately at the 12 o' clock position. Rotate the RH camshaft timing sprocket until the timing mark is approximately in the 11 o' clock position.

CAUTION: Unless otherwise instructed, at no time when the timing chains are removed and the cylinder heads are installed is the crankshaft or the camshaft to be rotated. Severe piston and valve damage will occur.

CAUTION: Rotate the crankshaft counterclockwise only. Do not rotate past position shown or severe piston or valve damage will occur.

Using the special tool, position the crankshaft.

Remove the special tool.
Install the crankshaft sprocket with the flange facing forward.

NOTE: LH timing chain shown; RH similar.

Install the LH timing chain onto the crankshaft sprocket, aligning the one copper link on the timing chain (6268) with the slot on the crankshaft sprocket.

Verify the camshaft sprocket to copper link alignment.

NOTE: LH shown; RH similar.

Position the tensioner arms and tensioners, and install the bolts.

Remove the retaining clips from the timing chain tensioners.

Position the crankshaft sensor ring on the crankshaft.

Install the engine front cover. For additional information, refer to Engine Front Cover in this section.


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