Oooops ! - Broken water cover bolt

[andrewkafp]

Re: Oooops ! - Broken water cover bolt

Clams "Goop" would be any RTV (Room temperature vulcanisation) Silicone, Black is usually High temp acetic cure that you make auto gaskets from, but they will all work in a low temperature application.<br />A brand name here in OZ is Silastic, or Permatex<br />There is also a high temp "Goop"

 

[Clams Canino]

Re: Oooops ! - Broken water cover bolt

Ya - Permatex black. Never use the copper (depicted) on these things - it reacts funny. Use the red for hi-heat.<br /><br />All those gaskets are readily available from Mercury individually. If your parts guy can't figgure out how to order you one - you need a new parts guy. <br /><br />-W

 

[Scaaty]

Re: Oooops ! - Broken water cover bolt

Always leave the EZout for the LAST RESORT. Best bet from the get-go is HEAT (be careful) then flood with PB Blaster or Kano Kroil...then if ya break it, take the Dremel and smooth the face, center punch, and step drill to the original tap drill. Try a tap...EASY..(use good tapping fluid) just as tough as an EZout so don't break in the hole either. Also try a small punch to pick/jab the remains out. USE THE BEST TOOLS. And you can always over drill to the next size, and also use Metric or SAE, which is closer or easier.And PLEASE leave a note somewhere in the motor so the next guy that works on it has knowledge of odd bolts. 21 years as a Journeymen Machinist, and could I tell you some horror stories. And I was relieved you got the EZ out removed. Other option is EDM machine (burn it out). Ya got lucky!

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

Hmmmm.. this is turning into quite an interesting thread. Hopefully useful for anyone who follows as this seems to be quite a common problem.<br /><br />Anyone got any comments on the "double helicoil" question (4 posts up) ?

 

[Dunaruna]

Re: Oooops ! - Broken water cover bolt

Originally posted by Duncan Ellison:<br />[QBAnyone got any comments on the "double helicoil" question (4 posts up) ? [/QB]

Never tried it and I don't think it would work, how would you marry up the threads? Some of the ones I've used are quite short compared to the original thread but remember that the heli-coil is much stronger than the original. <br /><br />I'll check a catalogue but I'm pretty sure M8 is available in 10mm, 12mm and 15mm long.<br /><br /><br />Aldo

 

[Dunaruna]

Re: Oooops ! - Broken water cover bolt

Hey duncan,<br /><br />Available lengths (Wurth & Heli-Coil catalogues)- <br /><br />M8 x 1: 8mm, 12mm & 16mm<br />M8 x 1.25: 8mm & 16mm<br />M8 x 1.5: 8mm, 12mm & 16mm<br /><br />Double coils are available up to 20mm long.<br /><br />What length did you get?<br /><br />Aldo

 

[mattsaks]

Re: Oooops ! - Broken water cover bolt

A sort of related question. What size drill do you use for the heli-coils? ie What size for 6mm? or 8mm? Thanks.

 

[Clams Canino]

Re: Oooops ! - Broken water cover bolt

The package will tell you what drill to use.<br /><br />-W

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

OK - I'm calling them Helicoils because that's what most people will know, they are actually a German equivalent called V-Coil which come in a beautiful case with the correct drill, insertion tool, tap, tang breaker etc.<br /><br />In my case the M8 is a 8.3mm drill.<br /><br />Dunaruna : They are 8mm long, which should be good enough for a water gallery cover bolt.

 

[Dunaruna]

Re: Oooops ! - Broken water cover bolt

Originally posted by Duncan Ellison:<br /> Dunaruna : They are 8mm long, which should be good enough for a water gallery cover bolt.

I agree, but I thought you were worried about the length - just trying to arm you with info.<br /><br />Aldo

 

[REN_IBOAT]

Re: Oooops ! - Broken water cover bolt

Old, but Interesting thread, and I just thought I would throw my chips in the bowl too.

First, I come from a small island in the middle of the ocean, so salt-water corrosion is more the rule than an exception here.

Secondly, EZ-out is good for nothing but earning money to the guys manufacturing them, Well perhaps removing a deep seated stud from a "not seized" bolt broken by over tightening would be a justifiable use, but I don't recall having ever extracted a single "difficult to get out" bolt from anything using those things..

When I need to get broken bolts out( I say when, not If.) I usually cover the flange surfaces with something, place a Nut, one size larger than the bolt I am trying to remove over the stud end, and give it a short penetrating Zap with the Arc welder and a Basic electrode. The thermal shock cracks the bond/seizure but is not large enough to cause stress in the block itself, and the new "bolt" will usually screw right out.
This also works if the stud is broken flush with the mating surface, but then it requires that you drill a conical hole in the nut to obtain sufficient room for the weld to bond.

R

 

[Michael F D]

Re: Oooops ! - Broken water cover bolt and more

Re: Oooops ! - Broken water cover bolt and more

Hello,
Engine top end has gradually degreased to the point of no power at all after1/3 throttle. Bogs
While trying to figure out why my 50HP merc outboard has no power I have rebuilt both carbs, they did need it. , No change,, compression test- good. Tested with meter everywhere, all good.,.Installed new stator, no change, new switch box, no change. While examining the engine at dockside in the dark looking for a electric leak I spotted a twinkle on plug boot #4 and had a AHAH! moment,,, for a moment . Well, it turned out to be water coming out from around plug#1.
What? So,,,read up on it and changed the Water jacket Gasket and 2 bolts did break on the right side,,, bummer! Soaking with penetrating oils for weeks did not seem to help as white oxidation appeared dry as a bone upon examination after bolt removal, After I got the jacket plate off I had two good stubs to work with. . I used a propane torch to heat them and spray more oil and tapped lightly with hammer for 10 minutes,, then gentle stress back and forth with large vise grips until they broke free and then I slowly went back and forth a little farther each time until it moved a complete turn,,then all the way out. rejoice!

Install new gasket,, test boat,, no difference,, red herring I guess. Really thought I had found my problem. Boat starts easily and runs fine at dock or test tank, top end has been slowly slipping away since last season. Is the exhaust cover gasket my next guess repair? Summer is slipping away,,need to get past this.

 

[emckelvy]

Re: Oooops ! - Broken water cover bolt

Well, this is definitely a good thread for how Not to remove a broken bolt!!!!

As we have probably figured out by now, the only GOOD way to repair a non-removeable broken-off stainless-steel bolt in an aluminum block is to completely drill it out and replace it with a Heli-Coil insert. The finished repair is Better than new.

I found out the hard way, fighting many Salty Dog motors here in the PNW, that you can't just drill out a stainless bolt and re-tap it. Any stainless left in the hole after you drill it out fouls and catches in the tap so badly that it'll just chew up any original threads that are left. Or worse, bind and break the tap!!!

Once you get the 'drill' down with doing a Heli-Coil repair, it's a cinch. You just gotta have a nice, sharp pilot drill, get an accurate center-punch and be real careful drilling. I find that a nice new titanium bit chews thru the stainless very well. Be sure to use cutting oil, or something like Marvel Mystery oil. WD-40 in a pinch but it's not nearly as good as the real stuff.

Once the pilot hole is drilled, use a drill about halfway-sized between the pilot hole and size of the Heli-Coil tap drill. You don't want to be removing tons of material on the last cut, it's better to work up to it.

Once you have the intermediate-sized hole drilled, blow out all the metal shards and drill the tap-hole. Blow out again and thread the hole using the Heli-Coil tap. Blow out hole again, screw in the insert IAW Heli-Coil instructions, break-off the tang and you're done!

If you held the drill and tap straight, you'll have a nice hole for your original sized cover bolt. The biggest challenge I have is getting the holes centered, once this is done the rest is a cinch.

One last thing, if you put a thin coating of Permatex No. 3 Aviation-Type gasket dressing on the bolt threads, they'll never seize again. Works great for Salty motors, it's so much nicer when you can get them apart the next time! I always have kind words for the previous mechanic of a motor I'm working on, if they took a few seconds to spread a little Permatex or even grease on the fasteners so I could get them apart!

HTH & G'luck with the repairs............ed