timing chain replacement on 4.0 liter sohc

[MLR1]

counter. Just went through the whole timing set swap myself. Every guide in the engine was broken.

 

[paramedic835]

Thanks so much. I'm going through the whole nightmare of having to replace everything after the rear chain broke and still I'm not sure if a valve suffered damage. So far it seems it's going to cost me around $1800.00 to fix all the damage. Why do Ford had to make this timing setup so damn complicated.

 

[SoFlaLivin]

Left timing chain 4.0

01 ranger 4.0 , I put marks on the cam and on the jackshaft sprocket and crank I loosed up the cam bolt every thing is fine as soon as i loosed the jackshaft bolts the marks moved my ?? is can i just line my marks back up and install chains and guide ... Thanks in advance

 

[2000StreetRod]

Jackshaft may move

01 ranger 4.0 , I put marks on the cam and on the jackshaft sprocket and crank I loosed up the cam bolt every thing is fine as soon as i loosed the jackshaft bolts the marks moved my ?? is can i just line my marks back up and install chains and guide ... Thanks in advance

When the front jackshaft sprocket bolt retaining bolt is loosened the jackshaft can turn relative to the crankshaft. When the crankshaft is at TDC with cylinder #1 on the compression stroke there is considerable valve spring pressure from the right bank that tends to rotate the right camshaft. Your right camshaft timing may have been lost.

 

[SoFlaLivin]

When the front jackshaft sprocket bolt retaining bolt is loosened the jackshaft can turn relative to the crankshaft. When the crankshaft is at TDC with cylinder #1 on the compression stroke there is considerable valve spring pressure from the right bank that tends to rotate the right camshaft. Your right camshaft timing may have been lost.

What will i need to do now to set the cams ? is there a step by step ?thanks

 

[2000StreetRod]

retime camshafts

What will i need to do now to set the cams ? is there a step by step ?thanks

A step by step timing procedure is listed in the following thread but uses the OTC-6488 timing tool kit: Cam timing procedure using OTC-6488

For your particular situation:

1. Complete the replacement of the left cassette components but don't tighten the left camshaft sprocket retaining bolt

2. Time the right camshaft by tightening the front jackshaft sprocket retaining bolt after positioning the crankshaft and the camshaft properly.

3. Time the left camshaft by tightening the camshaft sprocket retaining bolt after positioning the crankshaft and the camshaft properly.

The proper crankshaft position for timing is #1 piston at TDC on the compression stroke.

The proper camshaft position for timing is the timing slot at the end of the camshaft is below the axis of the camshaft and parallel to the head surface that the valve cover mates with. See below photo.

The camshaft position sensor nub on the left camshaft should be as in the photo below that shows the timing tool attached.

It will be necessary to prevent the right camshaft and crankshaft from rotating when tightening the jackshaft front sprocket retaining bolt. It will be necessary to prevent the left camshaft and crankshaft from rotating when tightening the left camshaft sprocket retaining bolt. In both cases the jackshaft to camshaft timing chain should be taught on the traction side when torquing the retaining bolt. Since you don't have the OTC-6488 timing tool kit you will have to improvise.

You may want to refer to the SOHC V6 camshaft timing threads in my helpful threads linked in my signature.

 

[SoFlaLivin]

A step by step timing procedure is listed in the following thread but uses the OTC-6488 timing tool kit: Cam timing procedure using OTC-6488

For your particular situation:

1. Complete the replacement of the left cassette components but don't tighten the left camshaft sprocket retaining bolt

2. Time the right camshaft by tightening the front jackshaft sprocket retaining bolt after positioning the crankshaft and the camshaft properly.

3. Time the left camshaft by tightening the camshaft sprocket retaining bolt after positioning the crankshaft and the camshaft properly.

The proper crankshaft position for timing is #1 piston at TDC on the compression stroke.

The proper camshaft position for timing is the timing slot at the end of the camshaft is below the axis of the camshaft and parallel to the head surface that the valve cover mates with. See below photo.
View attachment 67047

The camshaft position sensor nub on the left camshaft should be as in the photo below that shows the timing tool attached.
View attachment 67049

It will be necessary to prevent the right camshaft and crankshaft from rotating when tightening the jackshaft front sprocket retaining bolt. It will be necessary to prevent the left camshaft and crankshaft from rotating when tightening the left camshaft sprocket retaining bolt. In both cases the jackshaft to camshaft timing chain should be taught on the traction side when torquing the retaining bolt. Since you don't have the OTC-6488 timing tool kit you will have to improvise.

You may want to refer to the SOHC V6 camshaft timing threads in my helpful threads linked in my signature.

 

[SoFlaLivin]

Here's what i did i tighten the jackshaft bolt on the primary and lined up the marks i had on the Cams then I loosened the jackshaft on the primary chain again and lined up the crank with the marks i had on the jackshaft sprocket top primary . The marks were off by 1/8 of an inch , everything is lined up now, my ?? is when i loosen uo the chain tensioner LH or RH will the cams move again ??? . I have pic's but don't know how to up load em

 

[2000StreetRod]

what is marked?

Here's what i did i tighten the jackshaft bolt on the primary and lined up the marks i had on the Cams

Did you have marks for the right camshaft as well as the left camshaft? If so, what were they on? If not, how are you determining that the right camshaft is positioned properly relative to the crankshaft? Is the front timing cover installed? If not, how are you determining TDC for the crankshaft?

then I loosened the jackshaft on the primary chain again and lined up the crank with the marks i had on the jackshaft sprocket top primary . The marks were off by 1/8 of an inch , everything is lined up now, my ?? is when i loosen uo the chain tensioner LH or RH will the cams move again ??? . . .

By "chain tensioner" are you referring to the hydraulic/spring tensioner? The hydraulic/spring tensioner without hydraulic pressure is not strong enough to make the chain taught on the traction side of the cassette. That is why the tensioner is replaced with a special tool when timing each camshaft.

 

[SoFlaLivin]

Did you have marks for the right camshaft as well as the left camshaft? If so, what were they on? If not, how are you determining that the right camshaft is positioned properly relative to the crankshaft? Is the front timing cover installed? If not, how are you determining TDC for the crankshaft?



By "chain tensioner" are you referring to the hydraulic/spring tensioner? The hydraulic/spring tensioner without hydraulic pressure is not strong enough to make the chain taught on the traction side of the cassette. That is why the tensioner is replaced with a special tool when timing each camshaft.

Yes the hydraulic/spring tensioner ? should i get otc 6480 and 6481 to hold cam while installing new parts or will they hold when i remove the tension on LH ... I had marks on the crank sprocket to jackshaft sprocket , then from lh cam to cam sprocket ... TDC # 1 piston dead top on compression . I'll try to up load pics

I put marks with an awl

these pics were taken with a blackberry sorry

 

[2000StreetRod]

Left cam marks

If your new hydraulic/spring tensioner came with a compression O ring I suggest that you use bearing grease to hold it in position before tightening the tensioner. It easily slips out of position and then will leak badly no matter how tight you torque it.

I can see the marks on the left camshaft hub and the camshaft bearing cap. The left camshaft position sensor nub appears to be in the correct position. The left camshaft in the correct position is less likely to move from valve spring pressure than the right camshaft. When you remove the left hydraulic/spring tensioner the camshaft timing chain will go loose on the slack side but probably won't change on the traction side. I used an old tensioner as a tool. I cleaned the piston to remove all of the oil and then applied two part epoxy resin at the junction of the piston and the housing.

It would be difficult to obtain just the tensioner tool without buying the complete set.

Remember that the camshaft rotates one degree for every two degrees of crankshaft rotation. Be as accurate as possible.

Marks on the crankshaft sprocket to the jackshaft sprocket would assist in determining TDC and I can see in the photo that the crankshaft keyway is pointed up toward the axis of the jackshaft. However, the pointer on the timing cover aligned with the TDC mark on the harmonic damper is probably more accurate. When you loosened the jackshaft front sprocket retaining bolt you lost the right camshaft timing. It looks close in the photo but I suggest using a straight edge to check for alignment.

I found an allen wrench that just fit in the slot and then measured the distance with calipers from the allen wrench to the head on each side.

Once you get the timing close with the camshaft timing components installed and install the front cover I suggest that you manual rotate the crankshaft clockwise and check the camshaft timing again after two crankshaft revolutions.

 

[SoFlaLivin]

There is actually a couple of web sites that offer thr purchase of otc tools single new or used...
Thanks for your time .... You've been a great help !!!!.

 

[SoFlaLivin]

Fedex should bring the parts for the front on friday the 13th , lol . My ??? to you is once every thing is installed and torqued can i then put the cover back on or do i need it off to do the rear ? BTW, do know the torque spec's for jackshaft bolt and cam bolt
Thanks again

 

[2000StreetRod]

front timing cover

Camshaft timing (left and right) is normally done with the front timing cover and balancer installed as described in the post linked in post #26. The post also includes the torque specs.

 

[2009KVFD976]

do i need to remove the front chains in order to change out just the guides? i think one of the front guides is broken (light ticking noise coming from bottom front of the engine) idk which one may be broke, but its never been done since ive had it about 21/2 yrs and has 170k. i know this will be a pita but it has to be done soon...

 

[clean98x]

Did my rear timing chain without removing the engine. You can move the tranny back and put a jack under the back of the engine to make it move away from the firewall with plenty of room to get the job done.

 

[2000StreetRod]

primary & balance shaft chain guides

do i need to remove the front chains in order to change out just the guides? i think one of the front guides is broken (light ticking noise coming from bottom front of the engine) idk which one may be broke, but its never been done since ive had it about 21/2 yrs and has 170k. i know this will be a pita but it has to be done soon...

The primary chain (crankshaft to jackshaft) guide and the balance shaft chain guide can be replaced without removing the chains or retiming the camshafts. The primary chain guide rarely breaks. The primary chain tensioner (which frequently fails) can be replaced without removing the chains or retiming the camshafts. The balance shaft chain tensioner (which frequently fails) can be replaced without removing the chains and retiming the camshafts. However, to replace the base of the balance shaft chain tensioner the block girdle (upper oil pan) must be removed. To replace the left or right cassette (that includes the guide, chains & sprockets) it is necessary to retime the camshafts.

 

[2009KVFD976]

Thanks 2000StreetRod! Il look into getting all the new guides for it and hopefully replace them pretty soon. i didnt want to have to retime the whole setup. this will b the last time i get a ford vehicle, esp the 4.0 SOHC bc these motors r a pita. the noise started one morning after work and i was goin down the highway and was passing someone. il admit i shouldnt have gunned it that much just to pass someone but the tach was at or about 5k for about 2secs. i later arrived at a gas station and left the truck runnin and heard this noise comin from it. when i arrived home i got under while it was running and kept hearing it from the front lower of the engine. hopefully replacement of the guides fixes it and il keep my foot out of it.

 

[2009KVFD976]

Thanks 2000StreetRod! Il look into getting all the new guides for it and hopefully replace them pretty soon. i didnt want to have to retime the whole setup. this will b the last time i get a ford vehicle, esp the 4.0 SOHC bc these motors r a pita.

 

[2000StreetRod]

engine revs

I've run my SOHC V6 up to 6250 rpm (the stock limit) numerous times while on the dynamometer with no problems. The chains are most apt to slip when the oil pressure is low (at engine start) or when the engine is rapidly decelerating. The guides and tensioners just break with age (fatigue).