Serious front of engine oil leak '04 XC70

[prwood]

This actually happened to me just a few weeks ago. I ended up just pulling a new camshaft from an engine at the junkyard.

[jonesg]

Welp, now I've done it.....

Putting the cam holder tool on....both guides say put this on good and tight, the cam bolt is 85 lb-ft, blah blah......I sheared off a bolt.....INSIDE the G-dam camshaft. I wasn't even cranking on it - one hand on a 3/8 ratchet is not "good and tight." The instant I felt it start to turn, BOOM, snapped right off. 18-19mm of bolt are missing, deep inside the camshaft.

So this bargain version is what, EWK brand? Never heard of it. Had I been thinking, or not trusting this tool, I would have gone down and bought hardened bolts for it.

So now this afternoon job turned into a damn mess - I'm assuming the top of the head comes off to get the cam bearing caps off, to somehow get a bolt extractor in there..........??


My day's going great, thanks for asking, how's yours?

I re-read this, you made a mistake here.

Long shank bolts cannot take a lot of torque, the long shaft easily twists and sheers.
Similar bolts are used on my truck calipers and I broke one with a 3/8 ratchet,
Water pump bolts are the same design and are only rated at 12ftlbs. Careful.
My brake caliper long bolts were 10 ft lb and that's a 1 ton truck.

The clamp tool uses the tongue in the slot of thebcamshaft to stop cam rotation.
The long bolt only needs to hold the tool to the cam. It never works against the 85ftlb.

Any directions that say crank those extended shank bolts down hard are wrong.

I took my brake caliper to the local parts guy, not AutoZone type place, he smiled and pulled out a huge box of the identical bolt,
He said "they all do it".
This was the one I extracted by twirling it out with a pin.

[BlackBart]

Yeah, exactly, BOTH the video and the F250 guide say really tight - you can watch him with both hands at 2:30. These feel like cheep steel to me as well. I agree, it's just the teeth holding it from rotating. Let this be a warning to future fixers!

I don't get the twirling / pin description.


OK, depth of empty hole is 1 13/16". Depth with broken bolt is 3/4. That's 1 1/16", minus the 19mm missing end, should be 5/16" left, so it shouldn't be bottomed.

With the tool in place, the good bolt starts threading at about 13mm / 1/2" from bottom of bolt head to the tool face, so there's that much thread engaged, not just three threads.

The bolt's outside thread diameter is about 6.5mm. I assume that's a 6mm bolt. The unthreaded shank is 7mm. I will check on which bit(s) to try. I'm told Fastenal quality or nothing - not worth the risk.

There's about 6" of free space from the head to the ABS lines below the master cylinder to fit a drill in. Might have to get hold of a short case or 90º drill. The turbo hose and all that will come out of there.

The brass bushing or sleeve around the drill bit sounds like a genius idea if the sizes work out. I think the issue is going to be getting a drill in there, and somehow aligning with the threaded hole. Not sure how you'd get a punch in that small hole, 3/4" down in there.

The threaded shaft holds the 10mm head (6mm?) bolt that clamps the position sensor / tone ring onto those notches. How much thread damage is too much damage? Zero is preferable.

I watched a video where the guy drilled but not all the way through the broken bolt, then ran a reverse tap into it, and as the tap bottomed in the hole it backed right out. Depends on how snug this bolt is. There's no corrosion in the threads, just the tension against the tool, which is now gone.

Also, it's 14 degrees in the garage and dropping. Almost 40 yesterday when I started.

[BlackBart]

It's been suggested to me that when cutting the threads in the bore with the original tap, it's tapered of course, so the threads essentially stop even though there's more bore depth. That might explain the two rows of jimmied threads on the bolts, and why it slowed down and started to bind some, but not strip - it was still turning. The second I realized something was funny, it snapped. So the bolts should be spaced UP a couple of washers off the tool face I think. And yes, not so tight.

A right angle compact drill and a left hand drill bit are my next step. Another suggestion was to use the locking tool with one bolt installed to guide the drill bit straighter. There seemed to be quite a bit of slop in that tool though.

I feel a bit over my head pulling the head and re-setting everything so I'll try this first.

Moderators, please feel free to move me to the blunders thread!

[abscate]

Why not just leave the bolt shaft in the cam and see if the cam will lock to undo/ tighten the cam cvvt hub bolt as is?

You only need to lock the cam for the hub tire screws, it isn't essential to set timing. I found mine had to be removed to get hubs correct timed, by the way.

Hand tight on those screws or replace with good 8.8s

[prwood]

Just for reference, when this happened to me, these were the steps I followed:

0. Determined whether I needed to remove the bolt. Answer was yes, because the camshaft position sensor aperture would not screw back into place with the broken off bolt.
1. Drilled pilot hole in bolt using right-angle drill adapter. Broke three drill bits in the process.
2. Drove screw extractor into bolt. It seemed to be getting a good bite on the bolt, but then it stopped rotating, and then the screw extractor itself snapped off.
3. Removed camshaft from engine by removing cam cover. Attempted to do basically anything to get the bolt out on the workbench. No such luck.
4. Since the camshaft was already out at this point, went to the junkyard and pulled a replacement camshaft from another B5244T3 engine. Price was $40.
5. Cleaned camshaft cover/cylinder head, reinstalled camshafts, re-sealed cam cover, reassembled everything.

Hopefully you will have better luck and can remove the screw, but if not... Removing and reinstalling the cam cover to get at the camshafts is not hard, but is incredibly tedious. I've actually done it three times now:

First - to fix an oil leak in the spark plug tube seals which are between the halves of the cylinder head
Second - to remove the camshaft with the broken bolt, after I had reinstalled it in order to re-set the timing after the first attempt
Third - to re-seal the camshaft cover after it developed another oil leak after being improperly sealed the second time around (oil contamination in sealant).

The key (and the reason it's so tedious) is to get both surfaces of the cylinder head and camshaft cover completely clean, smooth, and free of any oil or contamination before applying the chemical gasket to re-seal. You also have to make sure all the screw holes on the cylinder head are cleaned of oil, because it can hide in there and spurt out when screwing the cam cover back on.

Regarding the source of these woes, the camshaft holding tool, mine was a CTA-branded tool that I purchased from FCP Euro:

https://www.fcpeuro.com/products/volvo- ... s-cta-2864

In my case one of the shorter bolts broke. Like you, I had also read the note in the VVT reset guide PDF that said you needed to get the bolts "quite tight", and this was a mistake. I had actually used the tool a couple of times before, but this was the first time I had read this guide and I should have trusted my gut and not made it so tight.

This latest time around, I ended up using the two longer bolts with the spacers, and just tightened them finger tight until there was no more play in the tool, then gave a slight (1/8) turn with a socket. You really don't want to take it any further past the point where the screw flange makes contact with the tool. I actually tried to source some higher quality replacement bolts locally, and couldn't find any. I even went to a specialty metric tool and screw shop that reportedly could get "any" metric screw one would need, and they couldn't locate any that were the right size.

[abscate]

When I did my 1999 CVVT hub last fall

viewtopic.php?f=1&t=83008&p=452202#p452202

jdawg and kahl saved my a$$ by warning me about these bolts. The collective is strong.

[jonesg]

Why not just leave the bolt shaft in the cam and see if the cam will lock to undo/ tighten the cam cvvt hub bolt as is?

You only need to lock the cam for the hub tire screws, it isn't essential to set timing. I found mine had to be removed to get hubs correct timed, by the way.

Hand tight on those screws or replace with good 8.8s

From memory, the bolt hole will be needed to attach the cam sensor rotor.

[BlackBart]

Answer was yes, because the camshaft position sensor aperture would not screw back into place with the broken off bolt.


Regarding the source of these woes, the camshaft holding tool, mine was a CTA-branded tool that I purchased from FCP Euro:

https://www.fcpeuro.com/products/volvo- ... s-cta-2864

Those bolts (in their pics anyway) look to be a higher quality than in mine. I won't use them again.

I'm glad to hear I'm not the only one who has ever done this.

[BlackBart]

When I did my 1999 CVVT hub last fall

viewtopic.php?f=1&t=83008&p=452202#p452202

jdawg and kahl saved my a$$ by warning me about these bolts. The collective is strong.

"... I broke one of the included chinesium bolts off..."

Mine says EWK...

Here's a fairly accurate view of the situation. This is a section thru the camshaft CL. I love the brass bushing or sleeve idea, but it's not going to help here. In my current view, the only resistance to backing this out is how jammed the bolt threads are at the tapering end of the threaded bore.

Camshaft section.jpg (11.37 KiB) Viewed 2256 times

Ohh...a quick search for EWK tools produces this corporate history........

"All EWKTOOL's Tools Are Manufactured By Advanced Processes, And Strict Quality Control Before To You."

"Because We Insist The Quality, So We Commitment The Best For You."