V8 Balance Shaft

[Roger_850T]

I'm elbows deep in replacing the balance shaft on my 2005 V8. I'm planning to write it up in a nice summary for MVS, but meanwhile, I thought I'd share along the way.

I'm still tearing it down. I've been compiling a parts list, but haven't ordered anything yet, waiting until I confirm it's the balance shaft bearing (and not something equally insidious) before spending a ton of dough. Tonight I got the cam cover off. Hooray!

For those that missed it, the car came home making this noise back in October: The vision I have in my head is the back end of the balance shaft with the ball bearings all out of the race and the shaft flailing around in the casing.

I'll post more as things progress.

Roger

[ggleavitt]

There are not many photos of the front of a V8 with timing AND valve covers off. There have been a couple spun timing cover studs reported over the last year so photos of the timing cover removed with or without how you did it and how you get it all put back together with the engine in the car would be particularly valuable.

Above and beyond what's going to be a very interesting post once you get a little deeper, even less photos of that. A personal thanks for the post this far.

My apologies for a sec, I wanted to use these first photos to make a point-
For those reading, as the owner of a V8, the Volvo 150k interval for aux belt with all the spinning parts is NOT reasonable in my opinion. While conditions may vary, there have been reports of vehicles in the 130k range with spun cover studs, caused by frozen idler bearings. I believe that 100k is a reasonable range for replacement, and there are a couple ways to do this from OE full assemblies to simple bearing replacement for the idlers. A number of posts on what needs done and how to do it (pay attention to tensioner release instructions), but if folks wait for too long to do the job, even if you do not have a counterbalance shaft problem, you'll be seeing the start of this photo set. I've done valve covers, cannot imagine voluntarily doing a timing cover as well with the engine in the car.

My apologies for the diversion, back to the previously scheduled thread....

[Roger_850T]

One of my takeaways is that I'm happy about how clean it is inside the heads and timing cover. Sure, there's some discoloration, but almost no sludge buildup anywhere. I've been running regular dino oil, (no synthetic,) and changing it every 3,333 miles. This strategy seems to be working nicely.

Roger

[abscate]

Roger

If you do have some down time can you document size and qty on critical fasteners?

At some point we probably won’t be able to get these From Volvo anymore and head, shank, tool bit and length will/3 good info to have in DIY threads

[Roger_850T]

abscate - will do. VIDA is pretty good about calling out the fasteners, but I'll add detail as I go along, especially where I wish I knew what it was before diving in.

As of yesterday, I'm so close to getting it all apart. The timing chain is out, the cams are out, and the head bolts are TIGHT! It's a 14mm head, my existing 14mm 6 point socket wouldn't fit, (it's an impact socket,) and my 12 point socket already slipped once. So last night I called it quits, and will be getting another 6-point socket today.

Roger

[Roger_850T]

Here's the picture I wish I'd had in advance. This is the timing chain tensioner, and I could not figure out how to get it to release. In the end I just removed the bolts, and it fell out, no harm, but that's not how I like to do things.

The manual says "insert a drift to hold it" but doesn't give enough detail beyond that. If you look at the picture, you'll see that the lever that looks like a chain link causes a cam to engage with the piston. To release the tensioner, first you have to take up the tension externally (to relieve the pressure on the cam,) then rotate the cam so the piston can be pushed back in the housing, then after pushing back the piston, rotate the lever counter clockwise to engage the teeth, and then insert a drift to hold the lever in the locked position.

Roger

[jimmy57]

Push on the plunger and move the chain link looking lever back and forth and the plunger will work its way in. When plunger is bottomed use a nail or similar and keep the link hole out padt body of tensioner to lock in bottom position.
The rear bearing cap bolts are security torx (to assure no one steals the balance shaft cap?????????) and you will have to knock them loose with hammer and chisel. They should turn out with fingers once loosened a wee bit. Use m8x1.25 bolt of similar length. You can tighten with crow's foot for the one(s) under head not removed.
There is a bulletin that has been posted on here about the hole drilling and the filing of the edge of lower bearing saddle (block filing)

[jimmy57]

Important note! The cams are easily broken when pulling caps down. Make sure the cams are turned a few degrees to a point where there are fewest lobes on their higher lift. I forget which way for intake or exhaust but it is 20 -40 degrees away from marka aligned point and the front cap is the most crucial. Run the cap bolts down 1/2 turn each and then move the cam back and forth a few degrees to assure it moves to relieve stress. The front journal with the dual cam cap holding the solenoids is the thrust control. The edge of cam cam bind there and break the cam so that is the area to focus on. I have broken a cam and it shocked me since no bolts got hrd to turn and I thought I was being cautious. Since then the cam being moved for less lift and turning it check for bind and to allow the cam to enter the thrust journal has resulted in no more broken cams.

[abscate]

I'll bet that broken cam customer discussion sucked. Bad day.

Some days, the dragon wins

[jimmy57]

An overheated V8 perished and had a donor card.................