I need to take off the crank pulley and balancer to remove the housing for the waterpump.

Is this a right or left hand threaded bolt?

Is there something I should be wary of in pulling these off?

Any tools needed? I have a couple of different three legged 'gear' pullers.

 

Don"t remove the big center bolt! There should be six allen head bolts that hold the pulleys and "vibration damper' to the "balancing disk" (MB lingo) The center bolt holds the "balancing disk" to the crankshaft and it is tricky to replace.

Once you remove the pulleys and the "vibration damper" the part that remains on the crankshaft (the "balancing disk") should have notches around the outside diamet which allow access to the lower water pump bolts.

I have replaced water pumps on 616 and 617 motors without removing any part of the pulley/balancer assembly by using a long handled (13mm?) box wrench It's tight quarters but I"ve been able to get in there.

Why do you want to remove the water pump housing? replacing the water pump only requires you to remove the top (fan) pulley.

 

Okay, I read your previous thread, I understand why yo want to pull the water pump housing. The bolts holding the fan to the water pump are a problem, they show up on almost any list of 617 engine design flaws.

Like wise the little bolts holding the water pump in the housing are fragile. I would try drilling down the center and and using a screw extractor.

The key is to get a REALLY GOOD QUALITY DRILL BIT. I never had any success drilling into the center of screws until a friend who worked in a machine shop cave me what he called a "centering point" it's a very short drill bit with a point and only about 1/8 of flute along the lenghth.

He also gave me a few cobalt steel 1/8 bits. The "centering point" bit is key. Everyone says to use a punch to mark a starting point for your drill. That never worked for me, I always had the drill bit dance off the center and often drilled down the threads, messing up the part I was trying to save. The "centering point" bit does the trick. it gives you a little hole about 1/32nd deep and if you get your regular drill bit in there.

Then use a cobalt drill bit and drill down the center of the broken bolt, put in the right size screw extractor and turn the extractor left from the get go. Don't try to screw in the extractor to the right like you would normally do when starting a screw, turn it left and keep going til it bites.

I wish I could tell you where to get good drill bits, I lucked out and my friend gave me a few, they are not marked with a brand, just "made in Brazil" I've used the same bit to drill into half a dozen bolts. The junk drill bits available at home improvement or auto part or hardware stores I would be lucky to get through one bolt burning up six bits.

But I believe that "centering point" is really the key. It lets you get the screw extractor directly in the center of the bolt and thus the twisting of the extractor is centered. Before I used the "centering point" bit even if I got an extractor in the broken bolt, I would just as often break the extractor off in the bolt and I believe it was because the twisting motion being off center of the bolt was not transmitted to the threaded outer diameter evenly.

I"m attaching two pictures of the "centering point" bit

 

You can buy cobalt drill bits at most NAPA stores, you can also get them in the McMaster Carr catalogue

 

Thanks oldrebuiltdodge, looks like McMaster-Carrr also carries what my machinist friend calls a "centering point" bit. The McMaster-Carr term is "Drill-Point Countersink"

McMaster-Carr

If I was buying, I'd probably go with a #1 size in the cobalt

McMaster-Carr

I can't emphasize what a difference having a bit that will drill a tiny pilot hole precisely in the center of a broken bolt has made in my bolt extraction success record. Before I used these bits to mark a center pilot hole, I NEVER used a broken bolt extractor (EZout style) successfully. Since using the "centering point" or "drill-point countersink" followed by A quality drill of the proper size, I have NEVER had a problem. I am sure there is are other ways to mark the center of a broken bolt but all the other ways I tried didn't work for me.

 

It's a bit late for the broken bolts on this one, but an old trick is to hit the bolt heads with a hammer then gently try to loosen them. This doesn't always work, but it has sure reduced the number of broken bolts that I have had to drill out. sometimes a little heat works too if it's safe enough to apply it.

 

I used to work at a Navel Shipyard and often had to deal with sheared off Bolts or studs.
What I got from the experiences is that every little detail helps towards success.

Each Bolt Extractor/Ezzie Out has a specific sized Drill you are supposed to use.
Always use a Center Punch to dimple the Metal so the Drill Bit will not stay were it is supposed to.
If you have a smaller diameter Drill Bit it is often beneficial to drill a Pilot Hole before using the correct sized Drill Bit.
If you get the hole in the Bolt drilled off center the Extractor is not going to work as well.
Heating the area around the Bolt with a Propane Torch helps to expand the Hole.
If you have time and can get some Penetrating Oil to soak into it that is also a big help.

The Old Style Extractors with the course spiral on them are OK on hardened things like Bolts but can expand broken off Bronze or Brass Fittings and that can damage the threads.
The Snap-on type with sort of a Twisted/Spiral Square cross section work on anything.
The Proto Square type ones are good on Brass fittings but the edges are sometimes delicate when you pound them into a hardened Bolt.

I have a set but have yet to use the short extractors that have fine of fine spiral threads on them. I wish I had had access to them when I was working.

If you have access to Left Hand Drill Bits of the Proper size and a reversible Drill Motor sometimes the twisting of the Drill bit and the heat of drilling allows the bolt to thread out during the drilling.

 

I did try that. I used Kroil penetrating old. I tapped the threaded stud and sprayed on the Kroil. Next day 24 hours, I did that again, tapped, sprayed the Kroil, tapped. I did that three days. On the 4th day, I tried to use locking pliers and wiggle the first stud left and right, sprayed some Kroil and work it out.

It would not budge, so I used a propane torch and added heat, got the aluminum hot and sprayed some Kroil on the stud, tried to remove it. No good.

I think at this point taking of the housing and either getting a replacement part is the best bet or trying PFBENZ's approach. I think if I do the latter, there will be 4 helicoils in my future. At this point, I think a replacement part is the best route.

I do want to thank everyone for the suggestions and advice.

The bits look good PFBENZ!