Broken Bolt on Exhaust Plate

[turtle1173]

Re: Broken Bolt on Exhaust Plate

Hello all,<br /><br /> I just wanted to keep you all updated a bit and perhaps provide some more information. I haven't done anything with my situation yet because it's been raining for the past couple days.<br /><br /> The exhaust plate is probably 3 inches wide, taking into consideration the outer plate, gasket, inner plate, and gasket. So these bolts are fairly long. If there are no threads in the plate, how effective is heat going to be? Also how effective will the PB Blaster be? Is any PB blaster even getting to the corroded threads?<br /><br /> If I get the plate off, even with a busted bolt, there will still be a couple inches sticking out from the powerhead.<br /><br />OB, the bolt is slightly below flush with the exhaust plate. I can't take it off yet because of that one bolt on the bottom.<br /><br /> I would prefer not to break the bottom bolt head off but let me ask you this: If it does break off, won't that just allow the plates to come off and then actually give me better access to the rest of the bolt for heat or PB Blaster?<br /><br />Just wondering....<br /><br />Shane

 

[G DANE]

Re: Broken Bolt on Exhaust Plate

Hi Shane<br /><br />I had a problem like it on a 73 evinrude. When I got the plate off ( which was hard ) the bolt was easy to unscrew with a visegrip. The aluminium corosion was sizing the bolt at the unthreaded part, going thru the cover. If its binding in the threads, it will most often break exactly at the outher end of threads as it is the weakest point. Perhaps you will find the same. Find something you can carefully squese between cover and block to get disassembled when all bolts are out or snapped.

 

[ob]

Re: Broken Bolt on Exhaust Plate

Turtle , after the bottom bolt soaks for a spell and the weather lifts attempt toremove it .If it comes smoothe great.If not ,don't force it to the point of breaking before reversing in and out and relieving gall.When applying heat ,concentrate the torch tip on the stud or bolt head until it is almost cherry red and remove heat.Let it completely cool down and try removing.This is a procedure I have carried out many times through my career as a powerplant tech and is quite effective as transmitting the heat down the lenghth of the threads and breaks down the scale that is causing the binding.Good luck and keep us posted.

 

[bonitoman]

Re: Broken Bolt on Exhaust Plate

Turtle, I would heat it and use vice grips to see if it does move. If it does not while your are heating around the bolt then I would take it to a machine shop.I am sorry to say that sprays do not soak all the threads on a bolt. P.B blaster is probably the best one and wd40 is worthless cause it evaporates. The wd stands for water disbursement and is good to remove moisture from uner a ditributor cap. As for lubricating properties it lacks them. Try to heat around the bolt if not go to a machine shop.

 

[wishinIwasFishin]

Re: Broken Bolt on Exhaust Plate

hi te<br /> after hearing you say that The exhaust plate is probably 3 inches wide, taking into consideration the outer plate, gasket, inner plate, and gasket. So these bolts are fairly long.I think that with heaps of care and time you will get this .good luck.<br />cheers daryl<br />ps. I use inox as my pentrating oil works great as it does not evaporate

 

[turtle1173]

Re: Broken Bolt on Exhaust Plate

Well, after much time, patience, and care the bottom bolt still broke off. It broke at the same place as the other one. It is about an 1/8" below flush with the exhaust manifold.<br /><br /> I still can't get the exhaust plate to budge. How do I get this thing off??<br /><br /> Unless some others have some suggestions, I'm going to work next on getting the broken bolt on the top off. I found a left-handed drill bit at a local store so I'm going to try that.<br /><br />Shouldn't the plates just slide off of these broken bolts since there's no threads in the plates? Or perhaps these so much corrosion that they can't. Anything I can do to help besides dynamite. I tried tapping on it with a hammer but it still didn't budge. I don't want to wack it too hard. I thought about trying to get a screw driver between the gasket and plate but I hate to risk damaging the metal. Any suggestions??<br /><br />Thanks for all the help.<br /><br />Shane

 

[alcan]

Re: Broken Bolt on Exhaust Plate

Hi Turtle<br /> This things are usually a real pain. Don't get frustrated, take your time. I know, thats what everybody has said. Your are correct the corrosion in the bolt holes is most of the problem. I would advise against drilling right now. The wedging of the screw driver is not a good idea either (as you note). Is there a ridge,lip or a bump that you can get on with a drift of some type? So you can tap it loose. I would go with the heat and tap, soak a little, then heat and tap. When you get that plate off the odds on those broken screws coming out nicely will greatly increase. Drilling now might spell disaster.

 

[Yepblaze]

Re: Broken Bolt on Exhaust Plate

It's just corroded all together. <br /><br />IF ALL THE BOLTS ARE OUT <br /><br /> You'll need to smack it around some till it comes free. A good slightly downward and to the side (on a thicker section if available) should start it to loosen. If you feel a little shy about a hammer directly on the metal use the blunt und of the handle of your biggest hammer.<br /><br />If it frees up to the mating surface, (you'll see a crack forming) and still hangs on the studs, it will require a lot of taps from different angles along with spray and maybe a slight pry with a putty knife.

 

[turtle1173]

Re: Broken Bolt on Exhaust Plate

Hello Everyone,<br /><br /> I haven't posted anything about my situation in a while. Winter has been pretty tough over here and today was the first nice day in a while that I could get outside and work on my engine.<br /><br /> I've got the exhaust plate off now. I also got the top busted bolt out as well. The bottom busted bolt is still giving me fits.<br /><br /> THe good news is that I have good access to the bolt, as the plate is off. The bolt is sticking out of the head about 2 1/2 inches. I've tried heating it and using PB Blaster but it's still not coming.<br /><br /> I'm having a hard time getting a good grip on it with my pliers. Should I try to get a different tool to hold on to this broken bolt?<br /><br /> What is the proper procedure for heating this thing?<br /><br />Thanks everyone,<br /><br />Shane

 

[jim dozier]

Re: Broken Bolt on Exhaust Plate

I am having a similar problem with the exhaust plate on a DT85 Suzuki. 8 of 15 6mm bolts snapped off even after extended torching and PB Blaster soaking. I was able to remove the exhaust plate and remove two of the 8 broken studs by welding a nut onto them with a MIG welder. The others just snapped again closer to the block. Them suckers are really in there. They've been heated repeatedly. I am now in the process of drilling the remaining six out for helicoil.<br /><br />I will echo the other advice to avoid the EZ-out. I had an unpleasant experience with a thermostat cover where the EZ-out broke off in the stud flush with the block. I did learn something then that I am using now. A carbide tile/grout bit for a Dremel grinder enabled me to remove the EZ-out before and I find that it is useful for assisting the removal of the old broken studs. I'v got 3 done and 3 to go.<br /><br />1. I cut off the stud flat with a disk cutter on the Dremel tool.<br />2. Then I center punch (as close to center as possible) the stud.<br />3. Using a small drill, I drill through to the bottom of the broken stud. Using graduated drill bits I increase the size of the hole in the center. When you are near the original diameter of the stud, if you're not careful the drill will wallow on one side (the side closest to the threads if you're not perfectly centered) and this is where the Dremel carbide tile cutter is handy.<br />4. The Dremel carbide cutter allows you to recenter the hole very slowy and remove the threads. Once the old threads are removed you can use the appropriate drill to install the helicoil.<br /><br />This is a lot of work and the idea of a trip to a machine shop is probably not a bad idea. You can blame them if they screw it up.

 

[Walker]

Re: Broken Bolt on Exhaust Plate

Oshi, heat the bolt stud itself until it gets red. Let it change back to regular color then grab it as close to the block as possible with a good pair of vicegrips and try to turn it.

 

[catfish]

Re: Broken Bolt on Exhaust Plate

do the threads go up to the top of the bolt.<br />if so try threading two nuts on the bolt<br />and screwing it down some then back out a <br />few times. if no threads on top file flats<br />on the sides of the bolt and use cresent <br />wrench to run it down and up! and use the pb<br />blaster. good luck!

 

[catfish]

Re: Broken Bolt on Exhaust Plate

did you get it out ?<br />bumping up post!

 

[kavin]

Re: Broken Bolt on Exhaust Plate

i've used a penitrant called aero kroil thats worked the best for me. everyone are right about ez out that should be your second to your last resort. with 2 1/2 inches sticking out you're way a head of the game. heat is your best solution. heating and oiling back and forth with some tapping on the stud and taking your time with this don't rush. one of the best ways i have found to remove a steel bolt from aluminum is to arc weld a washer to the bolt let it cool and remove with a good vise grip. a washer because most of the time i've been left with about the width of a washer sticking out of the block. if your able to weld a nut on then you would have a good aid in the removal. but don't use a vise grip to hold the nut up the whole time that you are welding. that would steal the heat that you want to go to the block. the aero kroil that i mentioned penitrates the smallest cracks that i've found. i think it was something like 5 microns of space to pass through. <br /> if you decide to drill it out make sure that you have a lot of sharp drill bits and or a good drill bit sharpener and take your time don't put too much pressure or the drill bit will walk. remember that the bolt that you're removing is probably hardened through the exhaust heat. good luck take your time you'll get it out. kavin

 

[Hooty]

Re: Broken Bolt on Exhaust Plate

Roger the Kroil Kavin. That's good juju. The only thing is you can't find it in stores. It's also excelent bore cleaner for pistols, rifles and shotguns.<br /><br />c/6<br /><br />Hooty

 

[catfish]

Re: Broken Bolt on Exhaust Plate

?

 

[bret walters]

Re: Broken Bolt on Exhaust Plate

ahhh the joys of saltwater corrosion. heat heat heat and more heat. forget the easy out. if you have to drill it out plan on helicoiling it. a machine shop might still be a good route.

 

[NitroBoy543]

Re: Broken Bolt on Exhaust Plate

Take a dremel wiht a cut off disk and make a notch in the threaded bolt, so its like a flat head screw. make it nice and deep and then use a pice of thin metal and turn it like a t handle. once its loose use a screw driver

 

[jim dozier]

Re: Broken Bolt on Exhaust Plate

I got the other 3 of my 6 broken studs out of my Suzuki DT85 with my drill and carbide dremel. All fixed with helicoils. One of the broken studs (one in the middle of the exhaust stream island)had a lot of corrosion around it and the seal face on the water jacket side has gone away. The motor is up and running but I had to use high temp RTV silicone to keep the bolt hole from squirting. I imagine this will eventually require having the sealing face on the block welded up. BIG QUESTION. Can this be done on the powerhead while it is still on the boat? If not, and I have to remove the sucker (powerhead) again, can it be done without disassembling the case? I really don't want to crack this engine if I don't have to. Any welders out there?