primary chain install timing off

[99XLT-Explorer]

i took the front engine cover off my 4.0 sohc because i was going to take off the balance shaft chain due to it being very stretched and slapping i got in there and found that the balance shaft chain was very bad with about half an inch of play.

While i was in there i figured i would change the primary chain,tensioner,and guide.Everything went good and got it all buttoned up and it was running rough and the one time i blimped the throttle i could tell the timing was off because i could here the exhaust in the intake.

The only way i could explain on how the timing could have jumped was when i was tightening the jackshaft sprocket i used a technique i found on here of someone putting a bolt through the sprocket and attach it to a chain to keep it still well while the chain was tightening i think the chain got enough slack to hop a tooth or 2.

what do you guys think? theres no way that i could have caused valve damage because i dont see how it would have run at all after the first crank.
im going to break back into it tomorrow and check it i took pics of how it was before i removed the chain so i will be able to tell if it jumped

 

[Jasonx521]

The process should be:

1) The passenger side timing pulley tighten while jack-shaft bolt is loose

2) Using the tensioner and cam hold down brackets provided with kit for the passenger (rear) timing chain
2a) Holding crankshaft at TDC
2b) Also holding the jack-shaft from turning
2c) Now tighten the jack-shaft bolt

3) Use tensioner and cam hold down brackets for driver side (front) timing chain
3a) Hold the jack-shaft from turning (Crankshaft should still be at TDC)
3b) Also holding driver side cam shaft, tighten the cam sprocket.

 

[99XLT-Explorer]

the motor isnt out i just had the front cover off doing nothing but the primary chain

 

[Jasonx521]

If you loosened the jack-shaft bolt, then you must go thru the entire timing procedure carefully to be sure you have it correct.
You don't have to remove the engine to time it correctly, but you wiill have to remove both valve covers and use the 4.0L SOHC timing tool kit.

 

[99XLT-Explorer]

i removed the bolt and the sprocket is on correctly just that the crank and jackshaft arent timed right. the only chain i removed was the primary one i believe the jackshaft might have skipped foward a couple teeth on the chain because i put the chain on the crank right back where it was i made a mark but doesnt the jackshaft sprocket have a mark to retime it with the crank?

 

[Jasonx521]

The jackshaft front sprocket does not have any markings. You must hold the passenger cam shaft and crank shaft both at TDC while the driversisde cam shaft sprocket is loosened, and you will install the provided tensioner (provides greater tension like when running) on the passenger side chain. Now while holding the jackshaft sprocket you can tighten the jackshaft bolt.

You now need to move the provided tensioner to the driver cam chain. Hold the crankshaft and driver cam at TDC and then hold the jackshaft sprocket again, this time tightening the driver cam sprocket bolt.

Take your time and do it correctly. The jackshaft bolt is not reusable. You don't need to loosen the passenger side (right) cam sprocket, but FYI it is reverse threads. The driver side is normal threads.

 

[2000StreetRod]

right camshaft timing lost

. . . While i was in there i figured i would change the primary chain,tensioner,and guide.Everything went good and got it all buttoned up and it was running rough and the one time i blimped the throttle i could tell the timing was off because i could here the exhaust in the intake.

The only way i could explain on how the timing could have jumped was when i was tightening the jackshaft sprocket i used a technique i found on here of someone putting a bolt through the sprocket and attach it to a chain to keep it still well while the chain was tightening i think the chain got enough slack to hop a tooth or 2. . .

The jackshaft front sprocket retaining bolt prevents the jackshaft and rear sprocket from rotating. Compressed valve springs try to rotate the camshaft to equalize spring pressure. Even though you kept the front sprocket from rotating I suspect the jackshaft (and right camshaft) rotated when you loosened the front sprocket retaining bolt. If the crankshaft was at TDC and piston 1 was on the compression stroke when you loosened the sprocket retaining bolt I estimate your camshaft as much as 20 degrees off. Please do not run your engine until you check the left and right camshaft timing. Hopefully there has been no valve damage yet. The right camshaft timing is easy to check without the OTC 6488 timing tool kit because its timing slot is at the front of the engine.

With crankshaft at TDC and piston 1 on compression stroke the camshaft timing slot should be below the axis of the camshaft and parallel to the head surface that mates with the valve cover.

 

[99XLT-Explorer]

okay so all i need to pull off is the passenger side valve cover to make sure the timing is correct? is pulling the spark plug on cyl 1 and using a coat hanger and feel for air pushing the best way? or can i tell at the crank? how can i hold the cam from turning without the special tools?

 

[2000StreetRod]

checking the camshaft timing

I suggest that you check the timing on both camshafts. Remove both valve covers and rotate the crankshaft to TDC using the pointer and balancer marks.

Check the left camshaft to see if the camshaft position sensor "nub" is above the camshaft axis.

If it's not rotate the crankshaft 360 degrees.
Check both camshaft timing slots. It will be a little difficult to see the left one because of being close to the firewall.

Some members hold the camshaft with multiple adjustable locking pliers applied to the shaft between the lobes and bearings.

 

[99XLT-Explorer]

okay i got the rad. out the fan off, alt bracket off, now i gotta pull intake off any other major things i have to pull to get to the valve covers?

i got the harmonic correct right?

 

[99XLT-Explorer]

there is a fuel line that runs down the driver side of the motor and over the valve cover on drivers. how can i disconnect that line or do i need to to pull the valve cover?

 

[2000StreetRod]

balancer timing marks

I can't tell for sure but it looks like the pointer is at the wrong mark. There are two marks on the balancer: 10 degrees before TDC and 0 degrees.

0 l l 10 > rotation direction

The vertical mark left of the 10 represents 10 BTDC
The vertical mark right of 0 represents TDC

 

[99XLT-Explorer]

ill check that mark but right now this is where the cam is at

the cam slot is almost parallel to the head however the small side of the slot is on the top not the bottom as it should

ill go check the harmonic now

 

[2000StreetRod]

disconnect fuel rails

The main fuel disconnect takes a special tool to release and even with the tool sometimes is hard to remove. Alternative method:
Remove fuel line support bracket bolt (8mm) and 2 bolts (8mm) on each side attaching the fuel line flange to the fuel rail. Separate (wiggle apart) the line flange from the rail being careful not to lose the O ring. Cover the exposed openings to prevent contamination.

The photo of the right bank shows the camshaft is 180 degrees off but the crankshaft may be 360 degrees off. You need to pull the left valve cover and check the camshaft position sensor nub.

 

[99XLT-Explorer]

the left side is pulled and the nub is 180 out and pointing down

i used the alt method to remove the fuel line and got it off

the harmonic was only a degree off from the first pic and is perfect now

 

[99XLT-Explorer]

going to go ahead and pull the timing cover on the front now

 

[2000StreetRod]

why removing front cover?

going to go ahead and pull the timing cover on the front now

Why are you removing the front cover when you haven't yet checked the timing and determined if it is bad? The camshafts are at least approximately as they should be. The right camshaft is 180 degrees off and the left camshaft is 180 degrees off so they are basically in sync. The timing tool kit uses the timing slot to lock the camshaft in place. Since you don't have the tool kit you can check the timing with both slots above the axis of the camshaft instead of below.

Since the crankshaft is now positioned exactly at TDC, measure how parallel the timing slot is to the head on both camshafts. Be as accurate as possible since 1 degree of camshaft error represents 2 degrees of crankshaft rotation.

 

[99XLT-Explorer]

if the cams are 180 out that would mean the timing is bad correct? the timing has to be off? the crank is still at tdc and i just pulled the harmonic.

i dont quiet understand what i have to do to line the timing up i thought i had to take the cover off take loose the jackshaft bolt and move the cams back to where they are supposed to be at tdc.

 

[99XLT-Explorer]

this is the passenger side cam as you can see not parallel

This is the driver side not parallel as well

Now what i have to do is take the jackshaft bolt off and turn the cams where they should be and then put the jackshaft sprocket and tighten it so it doesnt move correct?

 

[2000StreetRod]

no need to remove front cover

Sorry about not getting back to you sooner. The timing can be changed without removing the front cover. You can just loosen the camshaft sprocket retaining bolts, rotate the camshaft to the correct position and then tighten the bolt. There is no need to access the jackshaft sprocket. The left camshaft sprocket retaining bolt loosens normally (counter-clockwise) however the right camshaft sprocket retaining bolt loosens clockwise. Below is a photo of the right camshaft sprocket and retaining bolt in the center of the sprocket.

Ignore the red arrow pointing to the cassette upper positioning post.

Below is a photo of the left camshaft sprocket with the retaining bolt in the center.