So I think I'm in over my head, but it's too late now....

[mattawajeep]

1995 Buick Century Custom 3.1L V6 - mixing oil and coolant.



And the problem:



I've got it all apart, found the bad gasket - but it looks like I'll need to remove/unhook the push rods to get the new one on. Anyone have a tool for this?



Or can I just loosen the above nut and get it apart that way?

Anything else I should be checking for, or looking at now that it's all apart. This is the first time I've ever taken a car engine apart.

[White trash]

Typical pushrod GM engine stuff. Just pull the nuts and the rocker and fulcrum ball will come right off and the pushrods will be free. You can also just loosen the nuts and turn the rockers to allow the pushrods to come out.


When you put everything back together there are many schools of thought on how to adjust them but I let the engine idle with the valvecovers off and I loosen them one at a time till they tap then slowly tighten them back down till they quiet down. Once quiet I'll snug them down another 1/4 turn and thats that.

[mattawajeep]

So do the push rods need to be adjusted no matter how they're taken apart?

I remember watching the mechanic do something similar to your adjustment method on a tractor - but there's a whole lot more room involved. I'm not sure If I'll even be able to start the vehicle with the rear valve cover removed with all the junk that goes over the top of them.

[White trash]

Thats where another school of thought comes into play. Snug them down slowly one cylinder at a time with that cylinder at top dead center. When you can no longer spin the pushrod by hand back it up about 1/8 turn and leave it.

[mattawajeep]

Hmmm, yah it looks like I'll be needing to adjust everything anyway.

I hate trying to find TDC and getting everything all lined up. Think a whole bunch more research is in order so that I can figure out exactly what to do there. I didn't think this project would be that difficult.

ETA: Service manual says to torque nuts to 18 ft lbs and then inspect for "valve train noise". Great.

[SPR]

It looks like my wife's S10 blazer has a similer problem. Man I don't want to do what you're doing.

[mattawajeep]

It looks like my wife's S10 blazer has a similer problem. Man I don't want to do what you're doing.

Yeah, it's definitely not the best way to spend a weekend. Oh well, doing it myself is probably $600 dollars cheaper.

[White trash]

It looks like my wife's S10 blazer has a similer problem. Man I don't want to do what you're doing.

Lemme guess vortec 4.3? The plastic intake manfold is notorious for cracking. Not a hard one to replace, it just looks hard.

[SPR]

You're correct about the 4.3. I was quoted $600 to get it repaired. It does look like a miserable job... lots of little things stacked on top. Trash, How many hours do you think it takes to make the repair?

Good luck with yours Dale.

[White trash]

For the standard shade tree mechanic I'd say 4-6 hours. For a GOOD dealership wrench about 1 1/2. Remember dealership guys literally run with air tools and have done that crap 500 times before.

If you can put a V6 in your yota you can change the intake.

[rennat_2006]

The upper plenum housing all of the fuel injection stuff on the 4.3l is plastic but the intake manifold is metal, just a FYI.

Plan on it taking probably around 5-6 hours like mentioned above if it is your first one. Good news is the 4.3l you dont have to pull any pushrods or anything like that. Heres a trick when pulling the distributor, Turn the engine over until the rotor on the distributor is facing the firewall now make a mark where it is sitting, Now slowly lift up on the distributor and you will see the rotor turn(counterclockwise IIRC), When it stops turning make another alignment mark on the firewall. Now when you go back together you just line up the top mark with the rotor and it should fall in and twist itself back in and line up with the lower mark(first mark) you made, If it is off when it is fully seated you need to pull it back out and either go ahead 1 tooth or back 1 tooth.

To the Original poster...
Yes the make a tool that you stick under the rocker arm and pry it back enough to remove the pushrod so you dont have to mess with the adjustment what so ever. A buddy of mine that worked at the Mccurley with me back in 2006 had one that i used all of the time. You could make something yourself out of some flat bar but i cant remember exactly what it looked like.

[SPR]

I wussed out and sent it to a mechanic. Feeling a bit guilty so I spent some quality time working on the Toyota last night.

[mattawajeep]

To the Original poster...
Yes the make a tool that you stick under the rocker arm and pry it back enough to remove the pushrod so you dont have to mess with the adjustment what so ever. A buddy of mine that worked at the Mccurley with me back in 2006 had one that i used all of the time. You could make something yourself out of some flat bar but i cant remember exactly what it looked like.

Hrm, what to do... Buy a nice torque wrench, get a pushrod tool, or get both....

[Lurch]

Well duh they're tools. Get both

[mattawajeep]

Yup, think that's what I'm going to do. Man, the right answer is always the most expensive.

[mattawajeep]

Running out of curse words is a bad situation to be in. And I know a good deal of spanish too.

Thing were looking good, everything all cleaned up, new gaskets, new bolts. Push rod tool made removal and installation a breeze:



And then:



At least I got the stupid thing out. New TSB (02-06-01-003B) has different torque specifications and pattern for re-installation than the service manual. Bolt snapped clean off way before what it was supposed to.

So either I have the wrong bolts, the TSB is wrong, or this one was a dud (don't really want to try the others). This is probably why I'm a computer guy and not a mechanic - computers can be 10 times more complex but its a lot easier to undo.

Here's the TSB for reference:

Bulletin No.: 02-06-01-003B

Date: April 15, 2008
Subject:
Revised Cylinder Head Bolt Torque Specification and Tightening Sequence

Models:
1994-1998 Buick Skylark
1994-2002 Buick Century, Regal
2002 Buick Rendezvous
1994-1996 Chevrolet Beretta, Corsica, Lumina APV
1994-2000 Chevrolet Camaro, Lumina
1994-2002 Chevrolet Monte Carlo
1997-2002 Chevrolet Malibu, Venture
2000-2002 Chevrolet Impala
1993-1996 Oldsmobile Ciera
1993-1997 Oldsmobile Cutlass Supreme
1994-2002 Oldsmobile Silhouette
1996-1999 Oldsmobile Cutlass
1998 Oldsmobile Achieva
1999-2002 Oldsmobile Alero
1994-2000 Pontiac Firebird, TransSport
1994-2002 Pontiac Grand Am, Grand Prix
1999-2002 Pontiac Montana
2001-2002 Pontiac Aztek

with 3.1L or 3.4L Engine (VINs J, E - RPOs LG8, LA)

Supercede:

This bulletin is being revised to include a Notice advising that the cylinder head bolts are NOT to be re-used. Please discard Corporate Bulletin Number 02-06-01-003A (Section 06 - Engine).

Notice: This component uses torque-to-yield bolts. When servicing this component do not re-use the bolts. New torque-to-yield bolts must be installed. Re-using used torque-to-yield bolts will not provide proper bolt torque and clamp load. Failure to install NEW torque-to-yield bolts may lead to engine damage.

The cylinder head bolt torque and tightening sequence have been revised. This revision has been made in the SI. If you are using a paper version of this Service Manual please make a reference to this bulletin on the affected page.

The revised specification is as follows:



Tighten the NEW cylinder head bolts to 60 N.m (44 lb ft) in the order shown. Use the J 36660-A torque angle meter in order to rotate the cylinder head bolts an additional 95 degrees.

Think I'm gonna try and call the dealer on monday and see if they stock the bolts I need. Don't think these ones (felpro) are worth messing with.

[SPR]

Man, I feel for you. I spent $550 bucks to get our blazer done. I chose to forgo dancing girls and whiskey for a couple weekends instead of bloody knuckles, sore back, and big oil spot on my shop floor.

[Lurch]

Your over tightening it. I thought you were just doing intake gaskets not head gaskets. The intake bolts are probably close to 23 ft lbs. If you weren't so far away I'd come give you a hand. I know a couple of gm techs maybe I'll give them a call and check. What year, make, model, engine size is it?

[White trash]

Brand, model and engine size are the first sentence in the first post... Wake up Tim.


As far as I know he is doing intake gaskets only. My best guess says someone confused head bolt torque with intake bolt torque. The intake bolts should be a lot less than the head bolts.


I love me some google...

The lower has two steps.
First pass for the 4 center bolt's is 62 inlb
Final pass is 115inlb

First pass for 4 outer bolt's is 115 inlb
Final pass is 18 ftlbs

The upper is 18 ftlbs


Notice the difference in INCH lbs vs FOOT lbs.

[mattawajeep]

As far as I know he is doing intake gaskets only. My best guess says someone confused head bolt torque with intake bolt torque. The intake bolts should be a lot less than the head bolts.

That someone would be me. I figured the intake and head bolts were the same thing (mostly cause there are lots of references to that TSB on the internet in conjunction with this specific intake problem). Meh.

I'm gonna ignore all extra info I've dug up and go with the service manual numbers - which match White trash's google results.

Think I'll be fine re-using an old bolt in place of the one I broke?

[Wrench]

Yes, you can reuse the intake bolts.

Your head bolts are called "torque to yeild", which means they are torqued to the point of stretching the bolt and are a one-use item. The intake bolts are not.

To identify the head bolts, they will be much larger than any other bolts in that area, run parallel to the cylinder bore, and are placed in a pattern around the cylinder bore in the top of the head.

The big bolt head in the lower center of this pic is a head bolt:

[mattawajeep]

Thanks for the help everybody. Got the intake re-installed. Just need to put all the little bits back together.

If I ever have to do something like this again it should go alot faster. Especially since I now know how a v block is put together....