Timing Assembly and Rockers

[evomaki]

Montero Gurus,

This is kind of a silly question, but given the option with a vehicle that has the timing assembly off and the rockers off, would you install the rockers back on first and then the timing assembly, or the timing assembly first and then the rockers? This could be one of those either or deals. Maybe there will be way too much spin in the camshafts w/o the rockers on. Anyhow, if one way is even 10% easier than the other, sign me up for the easier. After doing those valve stem seals, I'm ready for a lot of easier. That was a nerve wracking job, the kind that once you get good at it you never want to do again. I do know that the cam timing marks are on the valve covers, so for sure those would have to be placed back on temporarily if timing assembly done first before final on the rockers.

Also anyone by chance happen to know if/where the neutral position is on the bottom end such that one can rotate the timing assembly w/o hitting a piston. Many thanks,

 

[normal_dave]

Not silly, but interesting. I'm not sure I'm ready to think hard enough to give a good answer, but I will say this, I would install the rocker assembly first, then setup the timing. Wait on the spark plugs of course, and turning the crank/cams should not be too difficult.

The valve seals are not for the faint of heart. What did you end up using to pull the old seals? I think one could make a small fortune building the proper tool to catch on the metal bottom of the seal and evenly pull the old seal loose, while still being able to reach down around the spark tubes for example. I can testify the results of taking care of the valve seals was so much worth the fight. Bleeding the lifters while I was at it completely eliminated the annoying lifter tick at idle, and driving rpms. I ended up replacing a few worn/broken lifters in the process, (see the club3g post I followed below).

Here's two posts that you might find helpful. First deals with the lifter bleed process, but also discusses proper rocker shaft installation and torque sequence. Second is a discussion about noise after timing belt install, but the Q/A is pretty informative.

lifter bleed/rocker install:
http://www.club3g.com/forum/maintenance/165458-how-bleeding-lifters-v6.html

Timing belt install questions:
http://www.justanswer.com/mitsubishi/8sxbg-mitsubishi-pajero-nl-just-done-timing-belt-change.html

 

[evomaki]

normal_dave,

Will check those posts out. I purchased these special pliers from Schley Products that are specially designed for grabbing valve stem seals. Check out ToolDiscounters.com. That job would be impossible without those. That job is a _itch even with all the right tools. There are some handy dudes on this forum. Guys write about this like no problem. I did it off and on over a couple of weekends and I'm no garage slouch. Also bought the Schley tool to compress the valve spring. There is some new feature available on this tool where the arm you push or pull on with your hand is separate from the bar that presses down on the valve spring. That was a good enhancement. Rope worked better for me than compressed air. One time I tried air pressure. The valve keeper was sticky and the valve actually opened as I pressed down on it with the tool,resulting in massive air leak. Freaked me out. Thought the valve might drop. Went back to using the rope.

Also got an OEM tensioner IncorporatedX has me convinced.

 

[nwoods]

Subscribed, for (near) future reference!

 

[normal_dave]

Thanks for the note on the special pliers.

This comes a little late for your project, but it was ideal when I replaced my valve seals. I may never us a conventional valve spring tool again... On engine, you would need compressed air of course, and it works great. I suppose equally well with the rope trick.

https://www.youtube.com/watch?v=b1DmJQ4Fods

 

[evomaki]

normal_dave,

I own that tool too. I spent some $$ at Tool Discounters. I did not care for it at all. People on this forum say they have used it. I don't get how. I could not get a good angle to give the hammer a whack. With the rope trick I found the valves had a little ability to slip down as the rope squished some (maybe a 1/16th inch). Even if I could get a good swing, that give in the valve took away the hammer's impact ability to compress the spring and set the keeper wedges into the retainer. With that Schely tool you could compress the heck out of the spring. I also gave up on the air method from my earlier incident. Also found out that slipping a 1/2" NPT brass nipple into the spark plug wells (one just long enough that it stuck out for easy retreival) reduced the I.D. of the pathway through which the rope slid through. This resulted in the rope slipping into the cylinder really easily and not wadding up in the spark plug well. Without that the rope was impossible to get to slip into the cylinder.

 

[normal_dave]

That makes sense. On the Lisle tool, it is really a heart attack maker the first time you whack a valve retainer a little too hard and hear that brief explosion of air! I used a hand held sledge, it provided just enough force to collapse the spring, catch the keepers and allow removal of the spring and retainer by hand. The reverse was pretty easy once you got the hang of it. I felt like a contortionist on a few of those. I pulled the battery and a few accessories loose from the fender wells on the '03 Sport, to get better access.

 

[RyanY]

Regarding the original question, I would install the cams and set up the timing before installing the rocker arms - that way you won't have any valve spring tension trying to turn the cams while installing the belt.

There is no neutral position that will enable you to rotate the crankshaft once the cams and rockers are installed. If the valves are being held open then the pistons have the capability of hitting them if they are not in correct timing.