Guy

Indeed they do, never had a full set of four come out cleanly.

Be sure to use antiseize on all new hardware when reassembling .

dr bob

Use An Impact Driver on the water bridge bolts to break them loose. Soak the bolts first with a good penetrating solvent like 50/50 ATF with acetone. Heat may hurt as much as it helps -- some temp differential might help break a corrosion bond, but the aluminum expands faster than the steel bolt so more heat = tighter. Plus the aluminum transfers heat away pretty fast. You really won't be able to get much heat in the top of the block with a hand torch.

As Guy recommends above, plan on installing new bolts when you put it back together. You probably want to chase the threads in the block to get any remaining corrosion out. Use a disk grinder with a metal-cutting wheel to cut a longitudinal slot through the threads on an old bolt for this duty.

Then use a good anti-seize on the whole bolt stem when you assemble, up to the bottom face of each socket capscrew where it mates with the water bridge. Adjust tightening torque down about 20% for the lubricated threads. You'll stand a better chance of getting it apart again someday in the future with this kind of care during assembly.

Chris Lockhart

That sucks Doc! I didn't realize that you'd run into that big of a problem with the broken bolt. I have an old school borescope if you want to use it. Call or text me.

drscottsmith

Yes Chris - you are correct!

Made a bit of progress today - both of the driver's side bridge bolts just came right out...quite unbelieveable!

Put the impact wrench on the back passenger side after soaking a good part of the day in ATF/Acetone mix. Looked it was starting to turn the entire bolt but alas, head broke off about three threads from the cap (flush with the top of the bridge). Lots of corrosion on the area where it broke.

After that I put another several rounds of ATF/Acetone on the remaining bolt on the front passenger side. We'll try it again tomorrow. I am only able to use a long allen wrench on that bolt as there is no room for anything else I have to get in there.

So we'll see what happens. Maybe only 1 out of 4 breaking will be a good start!

-scott

dr bob

Scott--

A hand impact driver is a hammer-driven tool that offers benefits of the impact from the hammer and from the twisting as you pop it with the hammer. "Impact wrench" offers the twisting only. It may of may not make a difference here. I know that with steel hardware into aluminum motorcycle cases, it makes a big difference. Doesn't need to be a really expensive one for this, by the way. Even the lowly Harbor Freight or Northern Tool version will be fine. Do use extended impact-rated drivers with it. Online from Amazon here.

The one you broke off already will come out easily with a Vise-Grip pliers once the water bridge is lifted off. With the bolt head missing, drown the remaining stub and threads with penetrant by filling the recess around the stub. You are almost there!

drscottsmith

Sounds good. Have been adding my mix of ATF and Acetone about every 4 hours or so to both the still attached bolt and the stub. Will try to get the impact driver tomorrow and give it a whirl.

-scott

RET

FWIW, here are a couple of things you might consider doing that have helped me remove corroded bolts: firmly tap the corroded fastener occasionally while it is being soaked with penetrating oil (ATF and acetone is a very good choice),and let it soak for a good long time (days, even...); and when it is time to remove it, unscrew it until it binds, then screw it back in a little, add more penetrating oil, and repeat.

Another possibility that worked well for me might be to weld a nut to the top of the broken bolt (electric weld, not gas...). I broke several bolts when I removed my water pump, most left enough of the bolt to TIG weld a nut on. The bolts, which had not turned at all when I used vise grips on them before welding the nuts, unscrewed easily.

The last broken bolt had sheared too close to the block for me to trust my nearly non-existent TIG skills. I ended up machining a drill guide, pressed it into the bore over the broken bolt of the old water pump, bolted the old pump to the block, drilled a fairly large hole through the broken screw, tried to use an easy-out, but ended up using a Dremel to slowly grind the remains of the old bolt out. A real time consuming PIA that I hope never to repeat...

Good luck.

drscottsmith

First a huge thank you to everyone who has been offering advice. Pics are below, but I finally have the water bridge bolts loose. Only broke one and was really concerned about another.

The trick that seemed to work was the combination of several days of secret sauce (ATF-Acetone) and the handheld impact driver. I was planning to post tonight something along the lines of "How long to wait is enough" and I whacked it a few more times with the impact, put the socket wrench back on, and low and behold it started to turn.

I went EVER SO SLOWLY as the one that broke had started to turn as well. When I could see threads turning at the same rate as the driver, I was relieved!

So, now to wiggle past the broken bolt, fish out the drill bit, drill out the thermostat housing bolt, replace all seals and etc., and then start putting it all back together.

Can't believe the difference in corrosion between the driver's side bolts (to the left in the pic) and the passenger side...is that typical?

thanks again all for the advice and encouragement to have patience. In a month of work that has become probably the biggest "tool" in the box - walk away when it gets rough!

-scott

skpyle

Very good, Scott!
Keep on keepin' on...


Seth K. Pyle

dr bob

Looks like your shopping list will include, at minimum, a set of new high-alloy bolts (they often come cad plated, although that won't help a lot...), and a pint of fresh anti-seize.

No answer on the difference in corrosion on the old bolts.

z driver 88t

Congrats on tackling that bolt. I had one of miine break off during disassebly and ended up sending the head off to a machine shop to remove it.

Good luck on getting the drill bit. Keep us posted.

dr bob

Good News is that, once the water bridge has been 'worked off' the stub of that broken stud, you can add a lot of heat to the stud to break remaining corrosion bond with the aluminum. I'd have my handy MAPP gas torch on that for a bit, let it cool for a while, repeat. After a few heat-cool cycles, a stud extractor or, in a pinch (so to speak...) a pair of sharp Vise-Grips. The stud remover places only rotational force on the stud, vs the Vise-Grip which adds an unwanted radial force component to the stub.

Have you shopped a replacement water bridge from Tom & Mark yet? Balance the cost against the fun of getting the old one off intact, plus the repair of the thermostat housing bolt threads. If the balance tilts towards replacement, grab your Sawzall with 18T metal cutting blade and carefully cut the old one off section by section. Stuff paper towels in the ports back into the motor to limit shaving ingress of course, and use your shop vac while you saw too. Once cut in at least halves, you can use a bit of brass persuasion and a pry-bar on the remaining pieces to break them free of the aluminum castings underneath.

drscottsmith

Yep - Have a price from Mark....in all honesty probably the best way to go. I dread cutting the old bridge though, as with my luck the entire thing will explode into a million shavings and exactly one will fall squarely into each cylinder head through a vacuum port I forgot to block and travel all the way down to the precise center of each connecting rod cap - squarely against the crank - just waiting for its chance to grind the bearing and shaft to bits when I try to turn it over for the first time...

...but that's just my luck! I am going to try again tonight for a removal and then will probably be calling Mark and Tom...