Chevrolet Trailblazer Valve Job Part 2; Reassembly 

+Randy White Can you do mine now?

Did u have to take tensioner bolts out of head through 2 access hole in front of head

dunno if you guys gives a damn but if you guys are bored like me atm then you can watch all the new movies and series on InstaFlixxer. Been binge watching with my brother lately :)

@Daxton Jace Yea, have been using instaflixxer for months myself :D

@Daxton Jace Yup, I've been watching on instaflixxer for since december myself :)

The age of small block fords and chevys is over, about the simplest you'll get these days is an LS.

I started using MMO - on this engine. Hopefully that will help with the tapping noise.

Carroll Crew removing the engine because if a screw extractor don’t work you’re fucked.

+Craig McDowell Gm actually created a new tool for doing this which is basically just a wedge on a stick. Works exactly the same way.

I'm saving your message on the chain tensioner just in case. haha. thanks

Do it in vehicle. You don't want to do this unless you absolutely have to.

+Adrian Lupparelli Usually I just hammer it with an air impact wrench, it's pretty tight. There may be some holes in the front cover you can put bolts through to hold it, or I may be thinking of another vehicle, Ive never tried to loosen a Harbonic balancer bolt without an impact before.

If you have a video time conversion machine everything is faster.

It can take 14 turns or more of the crank for the timing marks to line back up again. The marks have to be aligned while the engine is at TDC of the compression stroke on cylinder #1. Just being at TDC isn't enough, it has to be on the compression stroke.

your at the nerveracking part. I never used that tool, I used some wrenches and straps to hold the camshafts but you don't need to worry about that until reassembly. You need to hold the timing chain tight on the crankshaft sprocket to avoid loosing the timing, if it comes off the whole engine has to come apart to retime it. Rotate the crank until the #1 cylinder is at TDC and the timing marks on the chain are alined with the ones on the sprockets. I tied the timing chain tight with turnbuckles and bailing wire. tie the chain off to the sides, remove the cam sprockets, then re tie it almost straight up to the hood, lift the cylinder head and gasket straight up, retie them off to the sides again. maneuver the gasket around the timing chain while holding it straight up. Tie the chain to the hood through the new gasket and cylinder head. Lower the cylinder head and tie the chain off to the sides again. You need to keep the chain tight during all of this, I wouldn't even try to do it without an engine lift. This one was bought specifically for this job. Don't forget to unbolt the chain tensioners from the cylinder head before you remove it.. Watch all the way if you haven't already, you really want to know exactly what you'll encounter before you pull that chain off. I wasn't deatailed about how to tie off the chain, some parts were omitted due to time, When you tie it off follow what Ive written and keep it tight, you should be fine.

***** Thanks a lot man. I am finally ready to start putting everything back together. I placed the gasket on last night, with the help of a couple friends, just to realize after they left that we had not connected the black tubes behind the head, to the head. This seems like a ridiculously tight space, and I am unsure that I can connect them without pulling the head off again (which would be extremely difficult for several reasons). Do you have a tip on how I might tighten that bolt on the hose to the head?

Honestly, when I pulled it off I didn't know there was a bolt there, I ended up breaking the plastic around the bolt. There's also a little clip that just pushes into a hole on the head, I felt it was sufficient to hold those tubes on, given the lack of space for them to move around. If you can't get the bolt in I wouldn't worry about it, those tubes are for the smog pump so they don't see much stress.

***** Big ups for the fast responses man. It's people like you that make RU-vid a great resource! Thank you brother, I owe you a beer or two haha

+Daniel Lawrence It's not supposed to be adjusted. You're supposed to rotate it to the full advanced position before installation but mine was already at that position. Mine looked different from most pictures I've seen but it worked fine so I put it back in.

You should be able to just flip the link up and retract it. You may need to slightly release tension on it so the link isn't jammed.

I don't recall, mineral spirits should be fine though. Brake clean IIRC leaves a residue.

There's no special trick as I'm sure you figured out by now, just leave the bolts out until you get it lined up. One of the metal spacers may not be in all the way or upside down.

+achum2sum We don't know why the valve burned. Antifreeze level wouldn't cause this.Premature valve seat wear is very common on these engines. This one just happened to burn one for some reason.

It's normal for them to not line up every time the first cylinder is at TDC. 2 turns is not nearly enough for this engine. There are 3 timing marks on the chain, each one aligns with a corresponding mark on each sprocket. In order for them to line up again the crank has to rotate enough for the entire chain to make one full revolution, which is alot. Keep rotating and they will line up again. Just make shure they were aligned with the first cylinder on TDC of the compression stroke. It takes alot for a timing chain to skip a tooth. As long as the tensioner is working and you rotate it in the correct directionit should be fine. Make shure the flats of the "D" ends of the cams are facing up, then install the phaser with the timing mark aligned to the chain. The lettering should be level with the valve cover mating surface. Mine was already at full advance and didn't need to be rotated.

pfun41 hello pfun my name is Gabriel is there any sure way to make sure the chain and crank gear marks are lined as when I put the cam gears on, my marks are 3 to 4 links forward of my cam gear marks. So I think it is off timing. Or should I rotate 7 revolutions as you told the other guy so I can see if the mark return back on to the cam marks? Upon the headad being off i dropped the chain. So when I was turning the crank to clean the Pistons I the chain fell in then for a moment there I couldn't turn the engine like some of the chain was caught ul down in there.

Sounds like something let loose but these do have VVT on the exhaust cam which can throw compression readings off. Multiple cylinder misfires can mean its not hard enough to pinpoint a cylinder or that multiple cylinders have issues. I'd redo a compression test on all cylinders and then if it's still low do a leakdown test to see where the compression is going.

how much oil is your engine consuming? how many miles? if anything above 200k, it's pretty normal to consume oil about one quart of oil after 5k-10k. these engines are poorly designed, it's better to sell the car, else just keep adding oil. or move up the viscosity from 5w-30 to 10w-40.

Not always, it just did for me. 10mm hex socket IIRC for head bolts. Trying to do this without a hoist is asking for trouble.

@@pfun41 Thank you very much for your advice. I will try my best, one, not to snap a head bolt, two, not to jack up the shoe tentioner, three, hoist it properly.

@@rikarudo5 You're gonna snap a head bolt. Pretty much guaranteed. Just buy a set of extractors before hand and don't sweat it, they're easy to get out.

Ricky perkins If you get it right the first time I believe it was around $600-$700.

That's what I need to do to mine. How difficult was it for you?

im a little late but if you still wondering... when you take a look at any head bolt you will notice that it only has treads at the bottom without reaching the middle of it, so that way if the head of the bolt snaps loose, the thread will stay on the block and make it a pain more to lift and remove the head. once the head is off you just take some pliers and start removing them with the little remaining patience and pride you still hold

Make sure you use their torque specs and recommendations. If you try TTY tightening methods on standard bolts you're gonna have a bad time.

+Javier Lara forums.trailvoy.com/attachment.php?attachmentid=6894&stc=1&d=1254248410 forums.trailvoy.com/showthread.php?t=63402

John R McLellan, CH The lever looks like half a chain link. I just hooked it and pulled up and that allows the tensioner to compress.

***** Thanks. I broke three main head bolts taking the head off however they came out easy with an easy out. When I was putting the head back on I snapped the small bolt at the front driver's side flush with the head on an angle. If you want I can post how I solved it without taking the head back off or having to heli- coil the hole.

***** Thanks. I have a snake camera for seeing into place like that. Bought it on a hunch when it was on sale. Has it's own small screen but can be plugged into a laptop for a bigger view.

I didn't have any O2 sensor issues until it failed like 50k later.

Depends on the machine shop.

Just some dude in his driveway. A head gasket on these will require just as much work, as the head may be warped.

+Rafha Palafoxx If you get the chain out of time wile it's apart the entire Front timing cover has to come apart to retime it.

gabriel aramburu Could also be contaminated/old oil or the exhaust cam phaser.

My trailblazer is 2004 you can place an exhaust cam phaser. Engine 2005

What?

+t-bird shane Drill a hole in them and use a screw extractor. Once they break the remaining pieces are usually fairly loose in the block.

DO IT! But get an 06+.

Swapping out the engine for what?

I've done it twice. Huge pain in the butt

Unbolt the PCM, remove the bracket underneith it. Remove the alternator, there's a bolt for the intake manifold behind it that's hard to get to, also pull off the tube in the middle of the manifold, there's a bolt behind there too. The rest are easy to see, the one by the firewall is a PITA. When you have it all unbolted it will come off easily, if it won't move there's a bolt you missed.Don't try to get around removing any of that stuff, you'll only make it more difficult.

Thanks for replying bud, had a difficult time trying to get it offf, but finally got it. Keep up the good work on your vids and thank you very much for your help.

Yes, the lever looks like a chain link. You'll need to fish something down in there and hook onto it to pull it up. ( I used a coat hanger with a hook bent on the end.)Then with just a little pressure the tensioner pad should compress and give the timing chain just enough slack to slide the Exhaust Cam actuator onto the camshaft.

Thanx for responding so quickly. Yes, I made a rod similar to the one you made. I tried it out but I think I bent the hook end too much...the bent end looks kinda Vee shaped. I am going to cut off the bent end and rebend it to a 90* angle....Make it L shaped.

Ok, so you said that when you were tightening the headbolts, you heard the bolts creaking. Well, when did the creaking sound start? Was it when you were tightening them down to the first torque setting or was it when you were rotating the bolts the 155* turn? I tightened the headbolts to the initial 22lbs and already heard the creaking sound. I still haven't tightened them down 155* yet. I am wondering if I should tighten the final rotational degrees in stages. What I mean is: Should I tighten the headbolts 60 degrees and then another 60 degrees and then 35 degrees for a final tightening amount of 155 degrees? What are your thoughts on this?

When doing the final rotation to 155*. Once you torque the bolts past the initial Ft-lb reading you are stretching them and they have to be replaced if removed. Because you haven't gone past 22 ft-lbs they can still be removed safely. Remove them and clean the threads thoroughly. Use an old head bolt with a slot in it to chase the threads. Blow any debris out with compressed air. If they still creak at all lubricate the threads with oil. It's not shown in the video, but I had a bolt start creaking at 60* I got to 150* and it broke. I had to extract the broken bolt with the head installed and get a replacement from the dealer. I Had those threads spotless too. Because of this I recommend lubricating the threads if in doubt. It is recommend practice for most head bolts anyway. Torquing the bolts in stages is always a good idea.

Upon initial cleaning...as-far-as the headbolt holes are concerned, this is what I did: 1) Vacuumed out the headbolt holes. 2) Sprayed brake cleaner into the holes while I vacuumed the excess overflowing liquid until all traces of oil/coolant were gone. 3) Used compressed air to blow out the holes. 4) Used a thread chaser to clean up the threads. 5) Sprayed brake cleaner into the holes while vacuuming up the overflowing liquid till I felt all the debris was gone. 6) Blew out the holes with compressed air till dry. The creaking sound I heard was coming from the headbolt closest to the EX cam gear. The creaking began at less than the initial ft-lbs torque. All I can guess is that maybe I had missed cleaning this one hole properly. I removed that particular headbolt...welded my thread chaser to a long rod and chased the threads....vacuumed out the debris and then blew out the hole. Reinstalled the head bolt...torqued it to 22 ft-lbs then went 60 degrees rotation with no creaking. Continued with the remaining bolts then started the tightening pattern again with another 60 degrees. No creaking sound!!!! Things were looking great. Then I went to repeat the tightening pattern one more time with the final 35 degrees. The sixth bolt that I tightened the final 35 degrees snapped. I removed all the headbolts mad as hell. Pulled off the head. Looked at the remaining portion of the head bolt. It is down inside the engine block about half an inch. That's about where I'm at now.

any sucess on fixing the oil loss issue? Did you clean out the PVC hose?

@@voidisyinyangvoidisyinyang885 I've yet to have time to find pcv but with a closer look I did find a bad valve cover leak all the way in back where is was just burning off on the exhaust as it leaked. all of this was caused by my catalytic converter getting clogged putting pressure back into the motor. I just cut it off several mos back and straight piped where it was and have had no issues other than check engine light gives 420 code for catalytic system but that's it

@@voidisyinyangvoidisyinyang885 just waiting for warmer temp to replace valve cover gasket and continue look for pcv valve. if I find I'll post video on here about it since I can't find a vid on it

@@PplCantDriveOkc I found the PVC valve on rockauto - it is kind of tricky to get the part name correct. I didn't save the bag? I just installed it a week ago or so. First I used hose clamps - extended length - to pull the bottom of the PVC hose off the connector. Then I put some acetone in there to clean it out. The pressure shooting out was strong. So I figured the PVC hose was probably clean - actually I pulled it off the TOP connector and poured the Acetone down the hose. That was probably six months ago. Then I decided to just put in the new PVC hose recently. Thanks for that info on the valve cover leaking. I'll take a look - I just had a new catalytic converter put in because I added 300 ml of Liquid Moly and 200 ml of boron nitride to 7 quarts of new synthetic - and my spark plug wells clogged up from the Molybdenum - it got sucked in like some kind magnetic induction. My "test run" to work on the Snake Oil sounded terrible and then I was idling at the autoparts store contemplating what to do - the engine stalled out. I got engine misfire code after that - Cylinder Six. So I changed the spark plug and cleaned out that well - still had misfire general. Cleaned out all the spark plug wells - and all new spark plugs. STILL misfire. Put in all new ignition coils - fixed the misfire but now the CAT was burned out. I tried cleaning out the CAT - nope. So the Walker Cat is only $200 and the welding at the local Muffler shop was $200 (plus he gets to recycle the old Cat - probably got another $200 from that!). Anyway - I got a mechanical stethoscope since the bad Cat sounded like Engine rod knock and I was driving with low oil for about 30 miles - only like 3 1/2 quarts? I miscalculated when I had the wrong oil filter in. I never had changed my own oil before this!! haha. The autoparts store said STP Extended fit and I tried and thought I got it. nope. I thought I only lost a quart but I guess it was more like 3 quarts of oil? I still have to clean off the oil cover.... Anyway I put in the AC Delco filter - and with the new cat - no more misfire codes. I had tried to clean the CAT with the Lacquer Thinner -- so the new Cat had one misfire code - I think from some left over acetone - but I think it survived. hahahaha. OH yeah that mechanical Stethoscope from Harbor Fright - at first I thought - well the loud sound from the oil pan - the engine is doomed. But then I made sure to listen to the valves through the resonator and under the resonator on the sides - and it was JUST as loud and also it was that high pitch fast ticking sound. So no low knocking sound at all. So I think I just got super lucky hopefully as I have just about 272K on the engine. I'll see if there's any exhaust leak - but the muffler guy said my exhaust was good. He put in two previous mufflers for me and so he probably would have noticed any exhaust leak by the engine exhaust. thanks -

@@voidisyinyangvoidisyinyang885 surprisingly that motor holds 7qts. shocked me for a straight 6. lol. I always do my own oil especially after seeing things that can go on when I worked at a oil change place. where was the pcv located?

Rolled 230 a while back. Towing regularly and I don't baby it.

John R McLellan, CH I spent a good 20 minutes fishing around down there with that little hook and a flashlight, getting it on the lever is tricky but doable. To gain access to the tensioner itself the traditional way you would have to remove the timing cover and oil pan. Luckily with some patience you can just grab that little lever and release the ratchet mechanism. You will have to push the tensioner foot back in once you pull the lever and then keep it in or it will ratchet back out. Most engines including the atlas run clockwise when viewed from the front. The Delphi logo should be level when its all timed up.

John R McLellan, CH The GM techs are wrong and pfun41 is correct! The tensioner can be released without pulling the front cover.

@@SeekerFor1000 Hi Jack! Does the tensioner need 1) to be fully extended to then retract or 2) be completely un-loaded (no chain tension to retract? Or, can I keep the chain tensioned (so it don't fall of crank sprocket) even if it is not fully extended and just flip the link up? Thanks!

jean carlos salguero solorzano If you're saying what I think you're saying, you need to release the chain tensioner so that there is enough slack to get the chain on. There is a small lever on the tensioner itself. You need to get a hook onto that lever then pull it up while pushing the tensioner foot back in. This will allow you to compress the tensioner and get enough slack on the chain to put the actuator back on. keep pressure on the tensioner once you do this as it will ratchet back out if you don't

***** gracias amigo , ese gancho como es ?

I bent the end of a coat hanger into a little hook and used that to grab the release lever on the tensioner.

Billy Huskey 2005, The Cylinder head was redesigned for the 06 model year, by 07 the worn valve seat issue was resolved. Most of the time these problems show up early, if you make it to 120-130k without issue it's unlikely you will have this problem.

***** Will the 07 head fit the 05 engine?

Yes, it has a different valve cover and slightly higher compression.

***** Is there a reason your not answering the questions regarding the chain tensioner?

I thought I did, RU-vid made the comments system all funky and now I have a hard time keeping track of them.

John R McLellan, CH I'm not really shure if it's possible to do anything like that, usually when I need to share pictures I upload them to a hosting site. I use supermotors because it's mostly for car stuff but there are many others.

***** So you post them to supermotors and they post them to RU-vid?

I post pics to supermotors and then can link them in forums. Supermotors is a picture hosting site.

***** I will give it a shot. If anyone wants the lowdown on removing the oil pan from a 4 x 4 I have that down pat. I am shocked at how the Haynes manual leaves out details.

***** Thanks. Here is the link I hope to Supermotors pics. www.supermotors.net/getfile/1065198/fullsize/img_0349.jpg

+Craig McDowell Those head bolts break no matter once, Ive tried every trick and so have others. Just find the quickest way to break them and don't worry about it. Engine swap was out of the question for this one. 4X4 with the front driveshaft through the pan, more work than fixing it.

+Brandon Hudson That's odd. It would have to have a massive valve stem leak or tons of blowby for that to happen.

Yeah. I believe the intake valve on cylinder 3 is messed up. Because now it won't start. It usually would start but id have to stay on the gas pedal.

Like $700 I think. Most of that is machine work.

pfun41 Thank you very much sir

Fern Wolf Not too far, maybe an inch at most. You won't feel anything happen if you're just pulling on the lever as all it does is disable the ratchet. The tensioner is spring loaded so you'll have to push back on the tensioner foot while pulling up on the lever. I kept pressure on the tensioner foot while pulling up on the lever and once I got it I was able to push the foot back in. Keep tension on it afterwards or it will ratchet back out.

***** I am i the middle of dropping the oil pan and diff to remove the front cover. I have spoken to GM techs and they say it is not possible to push it back in.

That doesn't make any sense. It's a tensioner, all tensioners can be retracted somehow.

***** Your right about the tensioner going back in. I just can't understand why you didn't give detail about how to do it! The simplest way, and I screwed up, would have been to get one from the scrap yard see how it worked. The key is not to have tension on the arm and to very gently lift the half chain link! Dropping the diff etc.. is a royal pain in the ass.

My bad, sometimes things slip my mind, especially with large jobs like this. Often I forget to mention things until I'm editing. I try to add annotations for things like this that I remember after the fact. I'm going to add that little tidbit to this video. There was almost a month between when this video was filmed and edited. If I ever do this again I'm going to make a follow up video with everything that I didn't cover in the first one. I knew you didn't have to remove the tensioner, but I figured you had made your decision and were going to listen to the GM techs over me.

130k Later models didn't have as many problems though gm retired this platform completely.

So how's your 04 tappet noise? I have an 04 with 241K on it. So I started using MMO.

+Christian Flores Sounds about right to have a dealership do it, It's all labor. Though the engine doesn't have to come out if they know what they're doing, shop around see what others quote, auto repair costs vary wildly based on where you go but this job will cost a pretty penny no matter what. Most people sell the vehicle at a loss rather than pay to have this fixed because it's so much. If you do the work yourself you're looking at 600-800 for parts and machine work.

Thanks for the advice and have a happy new year

jore lopez Removing the Ac line would mean recovering all the refrigerant, then having to replace the receiver/drier since it would have been open for too long, then recharging. Not worth the effort if I can just work around it.

They (GM) should have routed that along the firewall

You have it wrong. Install with oil or you're asking for problems. Clean the threads out, clean bolts, oil the threads, torque them, then use angle gauge to tighten the rest of the way.

@@kc3689 how many of these have you done? Oil manipulates the torque and the threadlocker on the bolts. This isn't your 60s 350. And your comment about 'cleaning the bolts' prove your ignorance. They're throw aways since they have been stretched. Try again. Straight from GM service information,

@@richruiz9477 Just did one last weekend for a head gasket job. Cleaned out the holes real good, got the NEW bolts torqued and began the angle part and they started to creak long before they're supposed to. I wasn't going to pull the head back off to get broken bolts out so I pulled them back out, cleaned holes again and got another NEW set of bolts. Cleaned the residue from the package, oiled threads and they went in no problem and didn't start creaking until towards the end of the torque to yield phase like they're supposed to. Confused by your comment about a '60s 350 as I wasn't around in the century that engine came out. Not understanding what I meant about cleaning the bolts proves YOUR ignorance. Clean the NEW bolts when you get them out of the package since they have a residue on them and to ensure threads are clean. I'm not going to try again as my points have been thoroughly explained, however I will allow YOU to try again... but only once before I dismiss you for being so dense.

@@richruiz9477 "Oil manipulates the torque and the threadlocker from the bolts" I sure hope you're not using threadlocker on TTY bolts but judging by your intelligence so far I wouldn't put it past you. These bolts only get torqued to around 20 ft lb. Oil isn't enough to throw that off. These aren't diesel engines from heavy equipment that get torqued to 300+ ft lb before angle even comes into play. Angle is measured by how much the bolt has turned and that won't be affected at all by oil.

@@kc3689 Bolt Replacement & Tightening Important: Never reuse TTY main bearing or cylinder head bolts. Always make sure that the engine block threaded holes are clean and do not place oil or threadlocker on the bolts. Utilize a thread chase tool followed by cleaning with dry compressed air to insure threads are clean and dry prior to installation of new TTY bolts. Bolts that creak and snap while tightening will fail due to excessive torque caused by threads contaminated with debris, antifreeze or oil. Trace amounts of oil or antifreeze will cause this condition. In extreme cases the threads may need additional cleaning with a non-residue cleaner like a brake clean product followed by drying with clean & dry compressed air.