Oooops ! - Broken water cover bolt

[duncan_ellison]

Now I've done it, I was trying to remove the bolts on the water jacket cover to replace the rusted off brackets holding the plug wires and various pipes and replace them with stainless steel ones.<br /><br />I've I'd bothered to check iboats first, I would have found that these ALWAYS break.<br /><br />Well, I broke two next to each other. I looks like this http://www.sarian.co.uk/drat.jpg Anyone got any ideas on the best way forwards with these :<br /><br />a) leave them alone and hope for the best<br />b) drill and try an easy-out<br />c) weld a stud and try to get them out<br />d) drill out and re-tap<br /><br />Why don't I learn that if it's not broken don't try to fix it ! <br /><br />p.s. this is a circa 1982 3 cyl 70Hp.

 

[andrewkafp]

Re: Oooops ! - Broken water cover bolt

Salt water motors "Usually" break water cover bolts ... I think Clams and Ed Mc have posted that info up a few times.<br />Lucky they are the ones you can get at without P/H removal. If you aren't going to proceed with the cover removal, I would go (d) as I think the other methods have been raised and rejected on iboats for one reason or other.<br />You will need GOOD drill bits and lots of them, and your drilling skills need to be pretty good.<br />Good luck and keep us posted.

 

[wjphunter]

Re: Oooops ! - Broken water cover bolt

always try to avoid welding to something like this,It is possible to get a stray ground and boy that could be hard on motor bearings- last option.Personaly I would try the easy out (sprial type) they seem to work better. Start with a very small drill bit and work your way up to a sutiable size to remove the bolt.The larger the extractor the better chance you have to get it out.Being careful on to go to big. Also remeber to center punch the bolt it will be alot easier to start a small drill. <br />I hope my advice is help full.

 

[Clams Canino]

Re: Oooops ! - Broken water cover bolt

Before you do anything, check under the bottom side of the bolts to see if that block casting has "vestigal" places (slots) to insert a nut.<br /><br /> The older ones has a nut under each bolt. <br /><br />If your block has the slots - just drill it out clean and use a nut and bolt.<br /><br />-W

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

OK- Thanks guys. This board surely is useful . <br /><br />Looks like drill and easy-out, then drill and tap it that doesn't work. Might be a good idea to drill slightly oversize and tap in any case as the bolts I did manage to get out were showing bad signs of corrosion on the block threads (loads of white powdery stuff came out)<br /><br />Good point, that one though clams, I would not have thought of that.<br /><br />I'll post up how I get on.

 

[KCLOST]

Re: Oooops ! - Broken water cover bolt

Duncan, <br /><br />Since this is just a water jacket not the head, don't worry to much about drilling out all the holes and re-tapping. After you get the two broken bolts out... Find a tap of the right size for the current threads.. And carefully retap each hole to clean the corrosion out... After that, if you find a few that are in really bad shape then and only then do you want to re-tap to a larger size. And make sure you won't drill into the into any combustion or water passage area. There is also stuff called "thread-restorer" that can be used to build new threads that have been damaged... I've used it a few times and it works well.<br />Since these bolts are tightened to such low torque numbers, you don't need to worry too much about drilling and creating new....<br /><br />Use anti-seize for steel to aluminum (head bolts) when re-installing.

 

[Clams Canino]

Re: Oooops ! - Broken water cover bolt

Originally posted by Duncan Ellison:<br /> Good point, that one though clams, I would not have thought of that.

It's also the fastest fix. Drill it straight through and use 1/4-20 nut and bolt.<br /><br />-W

 

[jim dozier]

Re: Oooops ! - Broken water cover bolt

Do NOT attempt to use the EZ-out suggested by WJPHunter above if the engine has ever seen salt water (He lives in Kentucky and its fresh water only). The grip of corrosion on the broken bolt shaft exceeds the max torque of the EZ-out and you will break off the EZ-out and you will have to learn how to extract the extractor Drill out the broken stud and replace with a helicoil. The helicoil threads will be less likely (stainless steel threads) to break subsequent bolts. It also keeps the stock OEM bolt size.<br /><br />Make sure you center punch the stud before you drill. Start with small drills and increase the diameter in small steps. I find it helpful to use a Dremel tool with a carbide tile cutter bit to recenter the hole if it starts to drift off center.

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

Jimd - too late !!!! I just read your post and guess what I've now got a broken off EZ-out stuck in the block <br /><br />Out of the 10 bolts, 7 came off with no big fight, just a lot of creaking from the bolts and and cursing from me. <br /><br />One snapped off leaving a stub I managed to get out with a stud extractor, another went badly wrong so I've drilled and tapped it oversize to an M8 and the final one is going to be a real pig.<br /><br />In the position it's in, I won't be able to drill though and use the "nut and bolt" method as the rib on the casting ends up at the fuel pump see here http://www.sarian.co.uk/doubledrat.jpg <br /><br />Incidentally, I wasn't expecting to find a whole load of sand in the bottom of the water jacket, is this normal for a salt water run motor ?<br /><br />So - Jimd what's the secret to getting the extractor out ? I was going to get a supply of cobalt drills tomorrow and try to drill it out, but there has to be a smarter way.<br /><br />Also while I have you guy's attention , I managed to damage one of the holes on the cover (the one where the EZ-out went wrong). A pic is here http://www.sarian.co.uk/tripledrat.jpg I'm planning to put a thick washer under the bolt head to spead the load a bit. As you say KCLOST, there's no big torque on these bolts and I don;t want to have to spring for a new cover on top of the rest of this disaster ! Any comments guys ?

 

[jim dozier]

Re: Oooops ! - Broken water cover bolt

To extract the broken stub of the EZ-out use the Dremel tool (If that brand tool isn't available in the UK its just a small hand held high rpm grinder) with a carbide tile grout cleaner bit. You can chew up the stub of the extractor if you are careful. Go slow and let the rpms do the work. Make sure the bit is tungsten carbide. <br /><br />Once you get the EZ-out stub removed, just drill out the broken stud as I described in the earlier post. If you know how long the bolt is (using the others as a guide) make sure you only drill no further than necessary. There will be a small space at the base of the broken stud. I prefer to install helicoils as mentioned above.<br /><br />I would take the damaged casting (since you have it off) to a welder and let him heat the whole plate in an oven and them fill in the hole with a welder and redrill the hole, good as new.<br /><br />Sorry man, I like to be right but not late.

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

Jimd, somehow , I just knew you'd know how to attack this problem.<br /><br />I've got a drill similar to a dremel (you can get Dremels over here, there was a hillarious ad campaign where they showed them doing everything from putting up shelves to building entire houses - yeh right ).<br /><br />I'll seek out a carbide bit and let you know how I get on. It'll be a few days as work is taking over from boating for a couple of days

 

[wjphunter]

Re: Oooops ! - Broken water cover bolt

 

[andrewkafp]

Re: Oooops ! - Broken water cover bolt

Have to hand it to you Duncan. You are a pro-active dude. Did you end up having to pull the powerhead ? or did the bottom bolts come out OK?<br />You may be lucky enough to get a good cover from an outboard wrecker..<br />BTW great pics.

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

Hi Unicorn, thanks for the encouragement ! For now the p/h is firmly attached to the l/u and that's the way I aim for it to stay, but the way this project is going it probably wonlt be long before I've got even more of Mercury's finest spread over my garage bench. <br /><br />If this end up being a machine shop repair, I guess I'll end up learning how to separate the two, but it's the experience that this stuff is all about right ?

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

Just reporting back - Thanks to the advice from jimd I managed to extract the broken EZ-out. <br /><br />For reference this was a real difficult job, you don't want to go there, but if you do this is how I did it :<br /><br />I used a 1.5mm COBALT drill to make a couple of holes in what was left of the bolt itself.<br /><br />Then I used a thin (~2mm) solid carbide milling cutter from Dremel in a Dremel(lookalike) drill. Make sure you go at least 20,000rpm. These are expensive and tend to slip in the chuck. <br /><br />Work slowly - it took me a good two hours to finally remove the broken bolt and EZ-out.<br /><br />I then used a standard electric drill with an attachment from a company called Wolfcraft which endsures that the drill goes in exactly vertical and drilled a tapping hole and inserted an 8mm heli-coil to replace the 1/4"UNC bolt I broke.<br /><br />It was necessary to go up to such a large bolt because of the damage to the original thread hole. Fortunately an M8 bolt will just go through the cover plate holes. HOWEVER, this give you no tolerance at all in the plate fitting, so if you have made the new threads at all off centre from the original ones, you will need to SLIGHTLY enlarge the cover plate holes.<br /><br />I haven't actually started it again yet (waiting for a new gasket), but I don't expect problems. However, as I said earlier, this incident nearly cost me the motor. So my advice would be to only remove the water jacket cover plate if you absolutely have to and then to expect to helicoil at least some of the bolts. DON'T BOTHER TRYING TO GET THEM OUT WITH AN EXTRACTOR.

 

[Clams Canino]

Re: Oooops ! - Broken water cover bolt

Use some black silicone goop on the new gasket. Particularly around the plug holes.<br /><br />-W

 

[jim dozier]

Re: Oooops ! - Broken water cover bolt

Glad it worked out. If you are going to work on marine outboards you have to get handy with a tap and helicoil set. (Bet you are rethinking the hilarity of those Dremel adds ) Always use heat (torch) first not as a last resort and be prepared for broken bolts.

 

[stant1man]

Re: Oooops ! - Broken water cover bolt

im just about to carry out this procedure on my inline. Not looking forward to these problems but I will persivere.

 

[duncan_ellison]

Re: Oooops ! - Broken water cover bolt

Good Luck Stant1man, you'll need it. If luck doesn't hold out -report back here, someone is sure to help.<br /><br />Clams, good point WHEN I get the gasket (proving a little difficult to obtain locally), I was wondering what sort of "goop" to use. Exactly what sort of goop is "black silicone goop" <br /><br />Just as an interesting aside question, the Helicoils I got from the local engineering store are quite short, does anyone know if it's possible (reccomended) to follow one in after the other. I would have though there would have been a tendency for the threads to jam up on the bolt if they were not perfectly aligned, but the guy who sold them to me swears that because they are following a "master" thread in the tapped hole they will work fine. Anyone tried this ?

 

[stant1man]

Re: Oooops ! - Broken water cover bolt

Duncan, these guys are supposed to be good for parts, only heard good reports http://www.oldmercs.com/contents.html <br /><br />Im replaceing a lot more than just one gasket but if it was just the one you mentioned i would have made one. Heck, the old cerial box trick!(make sure you get a box with 33% extra free to cover the length of the cover lol) Take your cover, trace a gasket cover it in the world renound "goop"(i swear im gonna start a silicone business by that name) and bobs your uncle, job done. Repaired many an inlet and rocker gasket on cars this way. Dont see why it wouldn't work here.<br /><br />Your thoughts guys?<br /><br />Cheers<br /><br />Stan...............