Timing Chain Questions

[mt]

photos removed

[DeadlyPeace]

IMHO I think your best bet would be to go out and get a repair manual (Haynes and Chilton) for it. It will help you out a lot.

As for the TC it should be the mark on top for TDC. The one in the front should be for lining up the TC to the gears. There should be some silver plate on the chain. One at one end and two at the other end. The two together should line up on the camshaft gear and the single one on the crankshaft gear. The key on the Crankshaft should be at TDC.

FYI: To answer this question yourself you could have used the timing marks on the front of the engine to see where it line up at.

• Disconnect and mark all the vacuum, fuel, and water lines (one end only).
  
• Remove the 8 (I think) bolts/nuts that hold it to the head (obviously).
  
• Remove the EGR and Carb linkage.
  
• Underneath the intake there is an air box that has a metal air injection pipe connected to it. It wraps around the back of the engine with two bolts to the air box. Also a bolt in the back of the head that holds the pipe in place. You may need to loosen the other end of the pipe too (3 nut at the exhaust manifold).
  

• Unbolt the exhaust pipe from the manifold.
  
• Mark and remove lines.
  
• Remove air injection pipe
  
• Distributor
  
• Cam gear
  
• Remove head bolts. Don't forget the 10mm bolt at the front just before the cam gear (usually submerged under oil)
  
• Pull head with exhaust and intake still attached. Double check and remove slowly and make sure everything is disconnected.
  
• If too heavy or awkward then remove the the exhaust manifold
  

Also drain the coolant first before either of the above.

[fourwd1]

I would NOT pull the head if I didn't have to.

If you have no reason to suspect a HG problem, why waste time and money, and provide an opportunity to really f&*( up something that isn't broke.

And you do not have to pull the head to do a TC, even though the FSM says to.

[mt]

;D

Ok. First off, thanks. What I'm hearing is:

- I don't need to remove the intake or exhaust to remove the
head

- The first photo is TDC.

- I would have been able to use the pulley on the front of the engine to see where TDC was, but the guide I was looking at at that point in time said to remove it, then use the crank to find TDC. Oh well. Too late.

Now......166,000 miles. You would say that unless there's a problem, don't mess with the head, eh? No preventative maintance suggested when it comes to the head? Is that just because it's such a pain and so easy to mess something up? I'm getting both sides on this one, depending on who I talk to. I'd really rather not do it, but I don't want it to go out like it did on my '86 at 240,000, which isn't that far off now. I'd rather not tear into the engine again any time soon. But I also don't want to strip the bolt holes or anything. Hmm..

I've been using this board.marlincrawler.com/index.php?topic=45029.0 , which I'm pretty sure is the FSM online at a library. It works, but I'm just printing out sections as I find that I need them. Kind of annoying, but I don't have internet at home and can't really justify printing the whole thing on my work's dime....

[DeadlyPeace]

May 28, 2008 15:29:39 GMT -5 fourwd1 said:

I would NOT pull the head if I didn't have to.

If you have no reason to suspect a HG problem, why waste time and money, and provide an opportunity to really f&*( up something that isn't broke.

And you do not have to pull the head to do a TC, even though the FSM says to.

X2

I was thinking that in your 83 Shortbed Questions post you mentioned that you had/needed to pull the head, but I could be wrong. As fourwd1 mentioned there is no reason to pull the head if there is no signs of a problem. You will need to loosen or remove the oil pan depending on the type and condition of the gasket. And when unbolting the TC cover don't forget the 10mm bolt in head that I mentioned above. And when reinstalling it becareful of the part of the head gasket that goes between the head and the TC cover.


FYI: Here's a FSM that you can download and put on your computer at home if you want. You will need Adobe Acrobat Reader to view them, but you should be able to download/save the exe file to take and install on your computer.

[mt]

Ok. If I shouldn't mess with the HG, I sure won't. No, I didn't mention a bad head or that I had pulled the head on the other thread, but I did mention a LOT of things, including the timing chain, so that's understandable.

Thanks a lot. I will look at the oil pan, if it's leaky, I'll go ahead and pull it. Or if I notice missing chain guide pieces. It sounds like on this truck, because of the solid front suspension, I've got enough room to pull it without removing a bunch of steering linkages?

So........I guess that I've basically pulled everything I need to then (except for the oil pan & timing cover), and I can actually reattach some fuel lines. Next paycheck I can buy the chain kit and put it all back together.

Then all I need is a transmission & clutch! Oh boy. At least I've done that job before.

[mt]

Oooook. So I put the pulley back on. When the notch is at zero, there's nothing lining up on the cam. That's ok? Pulley notch at zero means TDC?

I've heard to check that the #1cylinders are loose.......well, I just can't figure out that. There seems to be a tiny bit of play in some, not in others, certainly not in any way that means much to me.

[DeadlyPeace]

You may need to spin the crankshaft around another 360*. The cam will make two revolutions to every one the crankshaft will make.

Both the intake and exhaust valves should be loose when the #1 piston is at TDC.

[mt]

I feel like I've done that............so with the notch at zero, I should be able to get the cam looking like the first photo? I guess the engine wouldn't run without lining up? Because otherwise I'd swear that I cannot get them to line up.

One more thing. What is this? I need to replace the gasket. Also, looking in there, it really needs to be cleaned! Is the fact that it looks like the next photo enough reason to justify pulling the intake so I can clean it? I'm guessing it would be a bad idea to chip any of it off into the hole.......



Buildup



Thanks again

[mt]

What do you think of this? The guides are still perfectly intact, but somehow the chain was making a TON of noise. I'm guessing this timing cover damage was from the original timing chain, not this newer one. But, what was making the noise if the chain wasn't hitting the cover?

I'll be checking my oil pump for damage this week, but hopefully I'll find all the little pieces in the oil pan........Oh yeah, and I know, way too much RTV. I won't make the same mistake.

[DeadlyPeace]

If your timing chain is loose enough then it could still make some noise.

It looks like you still have the original plastic chain guides too. Might want to change them over to metal ones while you're in there.

[mt]

Yup, I'm going to replace the whole thing. That's not the original. Somebody's been in there already. I can see wear marks on the cover, and they couldn't have happened with these guides in place. Somebody did this job not too long ago, the just did a bad job.

Should I be concerned about metal fragments having damaged other engine parts? I didn't see any evidence in the oil pump of having passed anything, but...you know. All that metal obviously ended up in the oil pan (but it's not there anymore, I pulled it over the weekend and it's clean). I wonder what noises I'll start hearing once the chain is quiet. Hopefully none.

Thanks a lot for the help. I'm pretty close to being fully disassembled, once I buy new parts, we'll see how good of a mechanic I am.

[mt]

Everything look ok here? Never been in so deep before, so I'm not sure what it should look like. I obviously decided to pull the head. I'm just going to take my time and a lot of photos and make sure I do it all right.



Also, on the back of the head, there's something with a couple bolts and a gasket. What is it? I've got a lot of oil all over the engine, and I want that to stop. Is this thing somthing I should remove and replace the gasket on, or is it not a cause of oil leaks?

[speedy]

Sounds like the cover is for coolant, I think that gasket comes with the major engine gasket kit. I thought mine was leaking from that for a long time but it turned out that it was leaking oil from the little half moon gaskets on the head.

[mt]

Yeah, I was wondering about those. They seem like they'd last forever, but maybe I should replace those too. There's so much oil, I think it's just hard to tell what's leaking. I'm just replacing gaskets as I come to them, but there are some things like that piece on the back of the head that don't need to come off, unless I feel like I should replace the gasket.

[DeadlyPeace]

It's been a while since I had the head back plate ("cover is for coolant") off, but I believe that just coolant does run though it so you would have any oil leaks from there. If you already have a gasket for it then you could go ahead and replace it if you feel like it.

If the oil is leaking from the back of the motor then more then likely it from the valve cover. For the half moon seals I usually put a thin coat of high temp sealant on the round part.

As for you pistons; did you get some water on the #1 piston when pulling the head or does it have oil on it? If it's water you're probably ok. If it's oil then your valve seals or rings might be bad.

BTW did you happen to do a compression test before pulling it apart?

[mt]

Great, thanks.

Good question...I know I was dripping oil and coolant when I pulled the head, but is that what's on the cylinder...good question. I'll stick my finger in it & taste it. Are valve seals & rings pricey? Hard to replace? Possibly a good idea to replace them anyways? Or no? I guess I can check into that.

So the buildup on them is normal, but oil would be bad?

No, I didn't do a compression test first. Oh well. Wasn't suffering from much lack of power. Mechanic mentioned it started running on only 3 cylinders for him when he was pulling it into the garage, but it never happened to me. Could have been bad plugs or wires or other stuff I guess, but could a compression test have helped there?

[DeadlyPeace]

Valve and rings are fairly cheap and aren't too bad to replace, but you would need special tool to do the job right. Plus if you do the rings you'll need to replace the rod bearings too. Speaking of which since you have the oil pan off; reach up and grab the bottom of each rod and see if you can move them around at all. There should tight with no movement.

Normally the top of the pistons should be clean or fairly clean like the two middle ones. A little build is ok too. Check the head for build up too, especially around the ehaust valves (the bigger of the two).

If it was runing on 3 cylinders then yeah it could have just a been bad plug or wire. Or if the rings, cylinders, or pistons were badly worn, but not likely the issue for that. A compression test would have helped in letting you know what was going on inside your motor like if the head gasket, cylinders, rings, valves, or valve seal were bad/worn.

FYI I would tatse that stuff. You should be able to tell just from the looks or feel of it.

[mt]

Yeah I wouldn't really taste it.

Thanks a lot. I'll check the rods to make sure they're tight. I'll also look into what it takes to replace that stuff, especially the special tool. Probably something I can rent if I need to.

[DeadlyPeace]

I figured you were joking about tasting it, but sometime you just never know with some people these days.

You'll need a valve spring compressor to for the head and a ring compressor for putting the pistons in. Might be a good idea to grab a Haynes and/or Chilton manual too if you haven't already done so. It will be very helpful. I think Haynes munals are better.