This week has been terrible for me. I finally got the chance this morning to finish getting my water pump replaced, got the new pump installed and set my torque wrench to 89ft lbs to tighten the water pump sprocket bolts, I'm using the online chiltondiy manual, which I've now discovered is wrong....The manual even gives a notice before this to "Pay special attention to avoid part damage and to ensure proper seating"......


So what do you think happened when I torqued the water sprocket bolt to 89 lb ft???? You probably guessed correctly, the head of the bolt snapped off. And where did it go? It went into the timing chain housing.......Can someone please help me with what I need to do to proceed safely from here? It is obviously in a very tough spot to get to. I have a flexible magnet coming tomorrow from Amazon to hopefully be able to fish it out. What if I can't fish the head of the bolt out? Thank you in advance....

 

You have a problem. If you cannot recover the bolt head you will need to open the timing cover for access. You also need to remove the broken bolt from the water pump hub. To be perfectly honest if you thought 89 ft/lbs was appropriate for a 6mm bolt the timing cover job is over your pay grade.

 

I'll admit my lack of experience as a mechanic, but the truth is that we all live and we all learn. My problem is not necessarily the task being above my pay grade, the problem is the the resources I paid (with trust) to guide me along the way were 100% wrong. I'm great at following directions, when the directions themselves are correct......The one working above their pay grade in this situation was the person who wrote the online chilton manual, and whoever reviewed what they wrote....

I have already removed the broken bolt from the water pump hub, that was a breeze. I'll hopefully be able to fish out the bolt head with a magnet today, and if not I'll start to research all the correct information in dealing with the timing chain, timing tensioner before I start to dig at it.

Thank you for your assistance, Andy. I wish GM had hired you to review and fix that chilton online repair manual, haha.

 

Kudos to you for successfully (except for the penultimate step) changing the water pump on that engine. It's a challenge even for experienced mechanics. You do follow directions very well if that's the only hiccup you encountered.

 

Thank you, Tony. In the future I will surely think twice before I torque a 6mm bolt with 89lb ft! I do now see how that is an outrageous amount of force for that little bolt. I just mistakenly trusted the source of info and thought "this is directly from GM, it can't be wrong..."(Chilton told me all their info is directly from GM) - We live, we learn.

 

It was probably supposed to be 89 inch pounds.
I usually just snug them. Kinda like spark plugs.
At least you got it out easily. That would be a pain to extract

 

You are totally correct, Billy (that it was supposed to be inch pounds). I really wish I would've just snugged them and moved on. In fact, I almost did, but backtracked to try to follow the repair by the book. And unfortunately for me, the book was wrong, ugh. I had the housing on for the water sprocket, and pulled it back off to tighten the bolts to the specs....

So I'm all in now, I spent an hour trying to fish the bolt head out without success. Is there any chance the bolt head could've dropped in the oil pan? Haha, that would be way too easy....

What is an estimated cost to have a shop get the bolt out for me?

 

Have you considered a borescope tool? Amazon sells one for about $33, and it may allow you to see the bolt head. Viewing the front area of the engine on a YouTube video, it's doubtful it went all the way to the oil pan. It is probably in a depression below the balance shaft timing chain (which also drives the water pump), and may stay put there until you can locate it and retrieve it. See this link for the tool:

See this video at about the 4 minute mark to see the area below the water pump sprocket: YouTube Timing Chain Video

 

Thank you for the link to the video, Tony. I actually ordered a borescope camera yesterday from Amazon, it was only 18 bucks. I ordered a flexible magnet at the same time but they only sent the magnet today. I'm hoping to have the scope shipped by tomorrow and I hope I'm able to see the bolt with it and fish it out. The video you linked to gives me a better idea of how to get it done. Much appreciated!

 

If the bolt head falls into the pan leave it there forever. The problem is that there is a lot of stuff between the access hole and the pan. When the guides break some of the plastic ends up on the oil pickup screen.
How many miles on your car? If you are between 100K and 150K you might as well replace the chain and guide parts. There have been several updates since 2002 and I always use Cloyes parts when I go into the timing components. Cloyes are OEM and through Rock Auto they are reasonably priced. I also like the Fel-pro gaskets I have bought from them. I have tried the less expensive gaskets and have had to replace them in short order. There are several torque to yield bolts involved with replacing the timing components so an angle indicator will be needed as well as the bolts. Do not try to replace the balance shaft sprockets just replace the chains, tensioners, all the guides and the oil nozzle. Replace the front seal and the cover gasket.