The engine is torn down. No oil pan, no oil pump, no head, nothing but a naked engine, exposed to the elements, and my friends she wants to have her clothing back, but I hesitate with this timing gear issue.

I completely agree that the timing gear needs to be replaced now, yet I will freely admit that I am more than a little timid at the idea of changing these timing gears on my 84 2.5 I have never performed maintanence of this type and the instructions in the manuals seem fairly intense.

What things do I need to be especially mindful about regarding this procedure?

The manuals state that once the cam shaft is out, I need to have the gear in a press to have it removed and installed - that means a shop must do this for me.

Some body allay my fears about this and help me have confidence that I am not going to screw up this stuff.

Not putting a new gear in now is asking to get it in the ____ later....

Under the intake manifold is a cover.

Under the cover are the lifters for your valves.

Loosen the valve rockers so you can pull out the push rods. KEEP THEM IN ORDER! They must be reinstalled in the same holes they came from!

remove the lifters. KEEP THEM IN ORDER! They must be reinstalled in the same holes they came from!

Look at the face of each lifter... It it flat? If not you really should put in new lifters and cam. (OE style cam/lifters aren't horibly expensive. I'm told that mild upgrades aren't too bad either.) Use a straight edje to check flatness.

rotate the cam and remove the bolts under the gear via the large holes in the gear. Those bolts hold the thrust plate.

Now carefully remove the cam. Use as much caution as you can find so you won't bang up the bearings.

wrap the cam in an old blanket and take it to a shop to have the new gear pressed on.

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11-Sept-01, The day the world as we knew it ended.

Try not to bend up the timing gear cover when taking it off. Oil pump drive shaft comes out too, if you haven't already removed it. Make sure the marks are lined up on the gears when you reinstall the cam. Shinerdc just did this, if you want to email someone who has done it recently.

Ogre, thanks for the info.

BTW, I already have the rockers and push rods out and in order, just like you said.

The extent to which I am working on this engine is completely new for me, so I am a little hesitant to jump right in.

But with help from you guys and the stupid manuals, I can usually fix/repair just about anything.

I am looking for some additional advice here:
A) Should I replace the cam?

B) If I replace the cam, which is best: a stock cam, or a performance cam; and why?

C) From what I see, a cam kit comes with new lifters, if a new cam is installed should I replace:
1) the cam bearings
2) the push rods
3) the rockers (what type is best, roller?)

Keep in mind that a valve job has been done to the head, but no performance mods (if they can be done, I know I did not have any done).

If the lifter faces are dished then the cam lobes are also worn....

If you install a new cam, put in new bearings. You need special tools for that. Considers having that job done by a shop.

You don't need new pushrods or rockers unless you've got bad ones or you just want new ones.

As for OE cam or "performance" one, That's entirely up to you. You might get a little more HP and/or Torque from an upgrade. depends on exactly which upgrade. The cam supplier can help you with that.

Well I have changed these timming gears twice without removing the cam, but since you have the engine out you may as well just remove the cam and have a shop press off the gear. If I were doing it, I would use this as an excuse to install a better cam. You could just remove the old one and leave the gear on it. Then you could just install the new gear and new cam. In either case it is not as difficult as it seems, it is actualy pretty easy.

Erik-

quote Originally posted by erikred: Well I have changed these timming gears twice without removing the cam, but since you have the engine out you may as well just remove the cam and have a shop press off the gear. If I were doing it, I would use this as an excuse to install a better cam. You could just remove the old one and leave the gear on it. Then you could just install the new gear and new cam. In either case it is not as difficult as it seems, it is actualy pretty easy. Erik-

How did you get the timing gear on without removing the cam from the engine, eager to know cause I just found out tonight that I may have a distroyed gear. damn thing lasted only 60k miles. would prefer not to tear down half the engine thank you
heres my thread... https://www.fiero.nl/forum/Forum2/HTML/017706.html

[This message has been edited by Back On Holiday (edited 01-26-2002).]

Back On Holiday,
I put some info on your original thread. 60,000 miles? That was about what I was averaging between blown gears on mine! After the third time I went to all metal ones!!!!

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Rod Schneider, Woodstock, Ga.
White 88 GT :)

Yes, rebuilt engine about 139k, have 197k now.. 56k miles when I think about it. well, at least I know it wasn't just me

Heres some posts I found when I used the SEARCH Option: https://www.fiero.nl/forum/Forum2/HTML/017560.html
https://www.fiero.nl/forum/Forum2/HTML/016305.html

[This message has been edited by Back On Holiday (edited 01-26-2002).]

Heating the cam gear in motor oil might work, but it's gonna stink up your kitchen & oven. Just make sure the cam has no nicks or burrs on it, as well as the ID of the cam gear. One thing you don't want to happen, is to have that gear hang up and shrink halfway onto the shaft. We used to heat up large gears and hubs in industrial applications, try putting them on, have them lock up part way to the shoulder. After we got them off, checked the ID's, found out that they were no longer true, in size or runout.

Thats what my dad said about it, possibility of getting stuck. might use the tap and push method, oh BTW to all that said about "Put rags in the hole so gear doesn't fall into the pan" you forgot, if your cars gear is already messed up, a good portion (2 or more teeth) will be in your oilpan already. mine is missing about 4 teeth and they are in the pan which I removed the morning, better off taking the pan off and cleaning up then getting old gear parts stuck in the pickup of the oilpump or stuck in the drainhole. 4 teeth is alot of material.....BTW thanks to everybody whos given advice about this, really helped me out alot!

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84se Silver 2m4
86se Silver 2m6

I've put up the preliminary copy of the cam change info I have here.... http://theogre.home.sprynet.com/tunnel6/l4cam.htm

WARNING! This document is not finished. It is not linked to the index. It may only be a temporary file until I get to the final version.

The document does explain GM's specs to drill a pressing hole in the cam. Follow them. If that hole is the wrong size then you could cause the cam to break or strip the hole pressing the gear.

Ogre, thanks for the article and everybody thanks for all the information.

I have pretty much decided to replace the gears with metal, I don't want to do this job again any time soon. And, to do this job via the tap method on the cam.

It will be a while (about a week or so, hopefully) before I can get to the work, but when finished I will provide an update to this thread.

Thanks again guys.

I am not sure what all this business is about pressing on the cam gear. I have never had trouble just putting it back on with the force of the bolt.

Yes, whenever the gears go bad you should take off the oil pan and clean it out. We did not do this once and a piece was sucked into the oil pump causing it to jam.