CAM gears totally loose ... are all the valves broken??

Sonix · **Posted:** Sun Nov 16, 2008 6:04 am

ok ...I'm continuing my engine problem on this post, cause my next question is not relevant to the first question anymore ..
You all know about the breakdown I had where the idler pulley broke....
We took the timing belt off, and noticed that the two cam gears (sprockets) are turning totally free ... you can even turn them with one finger!!

Does this mean that ALL the rockers broke?
The other thing we noticed, is that all 4 pistons still have compression, when we turn the crank... so no valves are stuck in the open position ...
So might this be a case where we might only have to open the top cover, and replace the rockers or lifters??
Is there maybe something else that could've broke, that can cause the two cam sprockets to turn freely like that??

ATXKJ · **Posted:** Sun Nov 16, 2008 8:56 am

When I bent the valves on a Fiat - there was no compression - pistons would spin with almost no resistance
I didn't try to spin the cams.
I think you need to pull the valve covers.

crdjon · **Posted:** Sun Nov 16, 2008 8:59 am

Having just had the top cover off my 2.8, I can say its a big job.

If the sprockets are still connected to the camshafts and they spin freely with the camshafts rotating as well, then Id reckon that either the lash adjusters are squashed or the rockers are bent or have jumped off. Knowing how careful you got to be to get the cover back on without them jumpin off this might be a posibility. As a side line there was a wrangler preparing for a trans australian trip with a 2.8 litrecrd in for a 5000 kilometre service not long ago and the owner got a call from the dealership that afternoon to say that all the rockers on the exhaust side had done just this. Its happened even wirhout the event you describe.

After an event such as you describe Id reckon it would be a really good policy to get the head/plenum cover off and check it out properly.

I know, its a pain getting the front off the engine and all the stuff off as well to do it, however, you got to check this out. Cam lobes or camshafts might be damaged as well

Just what I would do after an event like this.

BlackLibertyCRD · **Posted:** Sun Nov 16, 2008 1:03 pm

It is also possible that all the valves are bent causing the rockers to become loose not to cause any drag. I would listen to Mr Mopar and remove the head and check all the valves. I know this is not what you want to hear but it will be less trouble in the long run.

EDIT: you may have some luck, this is what I see in the service manual.
ARMS-ROCKER
DESCRIPTION
The rocker arms (10) are made of stamped steel and
serviced as an assembly along with the lifter. The
rocker arm (10) also has a fracture point. This fracture
point is designed to prevent engine failure if the
engine is not timed properly or the timing belt breaks
suddenly..

Sonix · **Posted:** Sun Nov 16, 2008 4:01 pm

ok ...so I'll have to take the top cover off to have a look at the rockers etc. etc. ... this will be my next project for the next week ...or two. I'll probably post ALOT on here to ask questions etc etc.
First question ... removal of the diesel injectors ... I REALLY don't want to break am injector while removing it ... any suggestions or tips??

BlackLibertyCRD · **Posted:** Sun Nov 16, 2008 4:37 pm

COVER-CYLINDER HEAD REMOVAL

DESCRIPTION
The cylinder head cover and the intake manifold on
this engine are made of cast aluminum. The cylinder
head cover also incorporates a oil drain back hole for
the crankcase ventilation (CCV) system..
REMOVAL

CAUTION: Before removing the cylinder head cover/
intake manifold (2) the witness mark on the
crankshaft hub must rotated to the 3 O’clock position
or, 90° after TDC to assure proper alignment
of the camshafts and the crankshaft. Failure to do
so could result in valve and/or piston damage during
reassembly.

1. Disconnect negative battery cable.
2. Remove engine cover and bracket (Refer to 9 - ENGINE - REMOVAL).
3. Remove the air cleaner housing (Refer to 9 - ENGINE/AIR INTAKE SYSTEM/AIR CLEANER HOUSING - REMOVAL).
4. Drain cooling system (Refer to 7 - COOLING/ENGINE/ COOLANT - STANDARD PROCEDURE).
5. Evacuate the air conditioning.
6. Disconnect the coolant recovery hose at the radiator.
7. Remove the charge air inlet hose at the coolant module.
8. Remove the upper radiator hose at the radiator.
9. Separate the A/C hoses from the cooling fan shroud.
10. Remove cooling fan and fan drive viscous drive assembly, along with the fan shroud (Refer to 7 - COOLING/ ENGINE/FAN DRIVE VISCOUS CLUTCH - REMOVAL).
11. Remove accessory drive belt (Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE BELTS - REMOVAL).
12. Remove cooling fan support (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - REMOVAL).
13. Disconnect the EGR cooler pipe behind the inner timing cover.
14. Remove generator (Refer to 8 - ELECTRICAL/CHARGING/GENERATOR - REMOVAL), and generator rear support bracket.
15. Remove the accessory drive belt Idler pulleys L.H.Thread.
16. Remove the drive belt tensioner.
17. Remove the power steering pump pulley.
18. Remove the vibration damper.
CAUTION: Before removing the cylinder head cover/intake manifold (2) the witness mark on the crankshaft
hub must rotated to the 3 O’clock position or, 90° after TDC to assure proper alignment of the camshafts
and the crankshaft. Failure to do so could result in valve and/or piston damage during reassembly.
19. Rotate the crankshaft hub to 90° after TDC (3 O’clock position).
20. Remove heater hose pipe fasteners.
NOTE: It may be necessary to rotate the camshaft gear bolt slightly to gain proper camshaft alignment pin
seating against the intake manifold. Alignment pins must seat flush against the intake manifold.
21. Install the intake camshaft locking pin VM.1052 and exhaust camshaft locking pin VM.1053 (Refer to 9 - ENGINE/VALVE TIMING - STANDARD PROCEDURE).
22. Remove outer timing belt cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - REMOVAL).
23. Remove timing belt (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT/CHAIN AND SPROCKETS - REMOVAL).
24. Install special tool VM.1085 and remove camshaft gears.
25. Remove timing belt idler pulleys L.H.Thread.
26. Remove inner timing belt cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - REMOVAL).
27. Disconnect coolant temperature sensor, camshaft position sensor, boost pressure/intake air temperature sensor, fuel injectors, fuel temperature sensor, fuel rail solenoid, and EGR air flow electrical connectors.
28. Disconnect the main engine harness connectors at the right inner fender well and position the harness over the left side of the engine and aside.
29. Disconnect the brake booster vacuum pipe from the EGR air control valve.
30. Disconnect the EGR cooler pipe from the EGR air control valve.
31. Separate the main engine harness from the bracket on the EGR air control valve.
32. Remove the EGR tube from the underside of the EGR air control valve.
33. Separate the block heater wiring harness from the oil level indicator tube.
34. Remove the oil level indicator tube from the EGR air control valve.
35. Remove fuel injectors (Refer to 14 - FUEL SYSTEM/FUEL INJECTION/FUEL INJECTOR - REMOVAL).
36. Remove fuel rail (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/FUEL RAIL - REMOVAL).
37. Disconnect oil separator outlet hose at separator.
38. Remove the oil separator from the intake manifold/cylinder head cover (2).
39. Disconnect the return fuel junction block from the intake manifold/cylinder head cover (2).
40. Remove cylinder head cover/intake manifold retaining bolts.
41. Lift cylinder head cover/intake manifold (2) from cylinder head (3).
NOTE: When removing rocker arm and lifter assemblies, Always keep lifters in an upright position and in
the order that they were removed from the cylinder head (3).
42. Remove rocker arm and lifter assemblies from cylinder head (3).
43. Remove cylinder head cover/intake manifold gasket (4) from cylinder head (3).

INSTALLATION
1. Clean and inspect sealing surfaces.
2. Install new gasket on cylinder head.
NOTE: Add a small amount of grease to the top of each valve to assist with rocket arm positioning.
3. Install rocker arm and lifter assemblies in cylinder head. Be sure to put rocker arm and lifter assemblies in
same location as removed.
CAUTION: Care must be taken when installing the cylinder head cover/intake manifold. Do not knock the
rocker arms off of the valves when installing the cover.
4. Install cylinder head cover/intake manifold.
NOTE: Be sure to lubricate cylinder head cover/intake manifold retaining bolts with engine oil before assembly.
If new bolts are being installed, DO NOT lubricate before assembly.
5. Install two cylinder head cover/intake manifold retaining bolts and tighten finger tight.
6. Remove alignment studs and install remaining retaining bolts. Tighten retaining bolts finger tight.
7. Torque cylinder head cover/intake manifold retaining bolts following procedure below.
CYLINDER HEAD COVER/INTAKE MANIFOLD TIGHTENING PROCEDURE
² Alternate between bolts #11 and #16 to seat cylinder
head cover/intake manifold on cylinder
head. Torque bolts to 7 N·m.
² Torque all cylinder head cover/intake manifold
retaining bolts to 25 N·m in numerical order starting
with #1 and ending with #16.
8. Connect EGR tube at intake manifold inlet tube. Torque clamp to 10.8 N·m.
9. Install turbo inlet tube retaining bolt at intake manifold. Torque bolt to 27.5 N·m.
10. Connect oil separator outlet hose at separator.
11. Install oil level indicator tube retaining bolt at intake manifold inlet. Torque bolt to 10 N·m.(88 in. lbs.).
12. Install brake booster vacuum tube retaining bolt at intake manifold inlet. Torque bolt to 10 N·m.(88 in. lbs.).
13. Install power steering pump reservoir in bracket.
14. Install fuel rail (Refer to 14 - FUEL SYSTEM/ FUEL DELIVERY/FUEL RAIL - INSTALLATION).
15. Install fuel injectors and fuel injector supply lines (Refer to 14 - FUEL SYSTEM/FUEL INJECTION/FUEL INJECTOR - INSTALLATION).
16. Connect camshaft position sensor, boost pressure/intake air temperature sensor, EGR solenoid, and fuel pressure sensor electrical connectors.
17. Install inner timing belt cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - INSTALLATION).
18. Install timing belt (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT/CHAIN AND SPROCKETS - INSTALLATION).
19. Install outer timing belt cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - INSTALLATION).
20. Remove crankshaft VM.1089 and both camshaft locking pins (VM.1052,VM1053) (Refer to 9 - ENGINE/VALVE TIMING - STANDARD PROCEDURE).
21. Install vibration damper.
22. Install generator (Refer to 8 - ELECTRICAL/CHARGING/GENERATOR - INSTALLATION).
23. Install cooling fan support (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - INSTALLATION).
24. Install accessory drive belt (Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE BELTS - INSTALLATION).
25. Install cooling fan and fan drive viscous clutch assembly (Refer to 7 - COOLING/ENGINE/FAN DRIVE VISCOUS CLUTCH - INSTALLATION).
26. Refill cooling system (Refer to 7 - COOLING/ENGINE/COOLANT - STANDARD PROCEDURE).
27. Install engine cover and bracket (Refer to 9 - ENGINE - INSTALLATION).
28. Connect negative battery cable.

BlackLibertyCRD · **Posted:** Sun Nov 16, 2008 4:52 pm

14 - 110 FUEL INJECTION - 2.8L DIESEL KJ REMOVAL

1. Review the High Pressure Fuel System Warning (Refer to 14 - FUEL SYSTEM - WARNING).
2. Disconnect negative battery cable.
3. Remove engine cover (Refer to 9 - ENGINE - REMOVAL).
4. Disconnect injector electrical connector. CAUTION: Repeated mounting of the retaining ring is not permitted.
5. Remove fuel return line from injector.
6. Remove fuel injector high pressure line (Refer to 14 - FUEL SYSTEM - WARNING).
7. Remove fuel injector retainer and retaining bolt.
8. Using compressed air, clean surface area in and around injector bore to prevent foreign material from falling into the injector bore, after injector removal.
NOTE: DO NOT use a wire brush to clean the fuel injector or nozzle. Possible restriction of the injector needle may result.
9. Remove fuel injector from cylinder head.
CAUTION: If the fuel injectors will not come out of the cylinder head, perform the following steps to prevent damaging other components.
10. Assemble and install Injector extractor special tool VM 9075A on to injector and cylinder head.

INSTALLATION
WARNING: High - pressure lines deliver diesel fuel
under extreme pressure from the injection pump
to the fuel injectors. This may be as high as 1600
bar (23,200 psi.). Use extreme caution when
inspecting for high - pressure fuel leaks. Fuel
under this amount of pressure can penetrate skin
causing personal injury or death. Inspect for high -
pressure fuel leaks with a sheet of cardboard.
Wear safety goggles and adequate protective
clothing when servicing fuel system.

NOTE: DO NOT use a brush to clean around the
injector nozzle. DO NOT lubricate area around
injector nozzle. The injector may become
restricted with debris.
NOTE: Be sure a new copper washer/seal is
installed on end of injector and the old seal is
removed, before installing in cylinder head.

NOTE: Apply anti seize compound to injector body.

1. Install fuel injector in cylinder head with new seal and O-ring.
2. Install fuel injector retainer and bolt. Torque bolt to 32.4 N·m (24 ft. lbs.)..
3. Install fuel injector high pressure line.
4. Install fuel return line to injector.
5. Connect fuel injector electrical connector.
6. Install engine cover and bracket assembly (Refer to 9 - ENGINE COVER - INSTALLATION).
7. Connect negative battery cable.
8. Perform the injector classification procedure with the scan tool (Refer to 14 - FUEL SYSTEM/FUEL INJECTION/ FUEL INJECTOR - STANDARD PROCEDURE).
9. Start the engine, allow to warm, Turn Off the Ignition, Inspect for leaks.

Sonix · **Posted:** Sun Nov 16, 2008 5:37 pm

ok ...maybe it's gonna take longer than 2 weeks ..

Thanx for the info ...

crdjon · **Posted:** Sun Nov 16, 2008 10:13 pm

Injectors are not too dificcult. Be gentle, they will free up with gentle movement, most significant item i noticed is the orange rubbery oring they have, one of mine was stuck to the injector receptacle wall on the number four so you might like to drop a bit of lube (not too much) in around these before removal to aid them freeing up after you remove the bolt attaching the clamp for the injector.

Number the injectors in the order they come out from so you get them back in the same order, the injector numbers are entered into the ECU. Protect them whilst they are out. As a suggestion I put my injectors and bolts and stuff into a prepared upturned cardboard box that I put holes into to hold the bits.

Number the bolts or put them into a sheet of cardboard and number the holes so you get them back in the same holes, etc etc, usual stuff.
In fact, number and mark everything so you get it all back in the original position. Just my suggestion.

Let us know how you go getting gaskets, I only needed to remove the head cover and at reasonably low kilometres it seperated easily, I reused this gasket, it is paper covered metal and it seems to have sealed OK. Dont ask why I did it, maybe Ill tell more later on.

Interesting info regarding the rockers being designed to break, supplied by someone previously. This might be a good thing if its the case.

MrMopar64 · **Posted:** Mon Nov 17, 2008 11:37 pm

The rocker arms in these engines are designed to be the "fuse" in the event that something bad happens, even the same case in the "new" engine used in current platforms. Although they do break as they're supposed to, some valves do unfortunately get bent hence why it's better to check them while it's apart.

Sonix · **Posted:** Tue Nov 18, 2008 8:39 am

Busy dismantling the engine .... by checking the valves ...do you guys mean sending in the top with valves to an engineering place to get proparly checked??

ATXKJ · **Posted:** Tue Nov 18, 2008 12:31 pm

The one I had - had visible damage - it was obvious.
if you inspect the surface you should be able to see if there was any valve to piston contact.

BlackLibertyCRD · **Posted:** Tue Nov 18, 2008 6:04 pm

Before you take the head off, check and see if the top of the valves are even heights. If they are you can pressurize each cylinder with air and listen for major air leak. Since the rockers are off there should be no air leakage past the valves seats. This can be done where the fuel injectors come out. Try to keep dirt out of the cylinders when doing this. You shouldn't need the adapter that is used with changing valve seals because your only checking if you have air leaking past the valve seats.

Sonix · **Posted:** Wed Nov 19, 2008 6:09 am

The thing that worries me about the valves is the following:
The tech at the service centre, told me that the valves could get a small fracture .... so without removing the valve, everything might "seem" to be allright .....then once the engine is up and running again, everything might look good, until a week or two, or even a month, down the line, that little fracture causes the valve to totally break, and then you have a broken valve in the cylender, hitting the piston, causing damage etc. etc. that littlke story made me a bit paranoid...

crdjon · **Posted:** Wed Nov 19, 2008 7:49 am

I suppose the only way is to remove the head and the valves and check them out. Have a look where they contacted.

From memory the valves are straight up and down motion so they should have contacted flat on the Piston. Assuming a flat top piston.

I mean if you are really paranoid then you replace them, if they look real good though, and they are not bent, suggestion, use a good magnifiying glass and maybe dye penetrant to check em. If they are not bent and you cant detect a crack then might be good to go. But something has let go somewhere hasnt it, spinning srockets and all that.

Im just rambling here..... some ideas for you.

ATXKJ · **Posted:** Wed Nov 19, 2008 11:46 am

Sonix
has this tech ever seen a valve break in that manner?
I haven't - I have seen valves bent and VW exhaust valves overheated and broken at the stem.
but I've never seen an edge crack propagate to a break.
and the engine is designed to break at the rocker arms if theres a problem.

The only real way to check that would be to pull it apart and Magnaflux it - at that point you're doing all of the labor for a valve job - so you might as well have them clean up the valves and put in some new guides.

I think it's overkill - but it's your Jeep and you need to have confidence that you can reliably drive it.

BlackLibertyCRD · **Posted:** Wed Nov 19, 2008 7:46 pm

Sonix
In a previous post you stated. "Was driving along the highway ... no problem at all ... then got off the highway, and at the first traffic light, the engine just cut out ... no engine light ...nothing ..."

Since you wasn't at the time driving down the highway but stopped at the traffic light the engine RPM would be much lower and less likely to damage valves. I was a mechanic for only 35 years and seen many bent valves that hit at an angle on interference type engines after timing belt broke. We are lucky that some thought was put into the design and the valves would hit flat and rockers would bend first. If you was winding it out to red line when the belt broke then valves and maybe engine is junk, but sitting at or coming to stop at traffic light is minor to compare to highway speed.

If you really insist on spending the time and money, maybe it would be better to get a new or re-manufacture head with a warranty. It will cost an extra $1200 for part only new.

crdjon · **Posted:** Wed Nov 19, 2008 8:34 pm

First things first, get the head/valve cover off first.

Look closely at cam lobes, rockers and valve heights for indications of anything, etc, let us know what you see before removing the head. pressure test and vacuum test if possible to see how the head is behaving still fitted.

Basically dont stress too much about what might be, disassemble what you need to prove/disprove your concerns. Keep goin till you get that warm fuzzy feeling.

First thing is to determine why the camshafts were just spinning is it not?

Sonix · **Posted:** Thu Nov 20, 2008 2:38 am

Correct ....at THIS point, I just wanna see what the heck is going on under that top cover! :roll:

I still have this gut feeling that it's not as bad as I think .... At this point it's just a bit of a concern that the cam pulleys are turning totally free ....
We are just busy sorting out the @#$@# insurance I took out on the mechanical part ... by the looks of it, they will pay out about 80% of the price of the parts.. only problem ... my father in law's workshop is not on their list of approved service centres ... so once we have that little "technicality" sorted out, we'll start opening up and see what's "hidden" underneath :wink:

Sonix · **Posted:** Sun Nov 23, 2008 3:42 pm

Alllllllrigty then .... removed the valve cover today ... man it looked like a war zone! ...you just see dead rockers everywhere!
All 16 rockers are broken ... :cry:

allthough I've been expecting that ...
Tomorrow the top comes off ... all the valves looks good at this point, and all of them still seals nicely ... but with all the advice so far, I don't wanna take a risk, and will feel much better once the head and valves has been properly inspected ...
Now I've got another question .... at the stealership, they ask about R737 for one rocker ....and I need 16 ... that comes to R11800 ... at the current exchange rate, that's about $70,18 per rocker ...giving total of $1123 ... Any good ideas on where I can import them from?, and at what price??

CAM gears totally loose ... are all the valves broken??

Who is online