I've snapped the head off my thermostat cover bolts...
Discussion
EDIT: I've fixed it! See a later post for how
What next? Other than riding my bicycle to work for the next week
I've drilled a hole in each and tried using my bolt extractors but not enough purchase so I tried drilling the bolts out. Combination of me being rubbish and the drill mean that I've gouged the cover itself. So that needs replacing, no biggie, I can get that part from autolink for £12 ish.
But how to I get it off without damaging the thermostat housing, that's much more expensive and I'd have to take the timing belt off (which I just paid someone to replace, would've been nice if they'd spotted the thermostat gasket was leaking whilst doing the work, they're a well respected 'specialist in these parts).
Note that I'm not shipping this off to a garage again, get fed up of other peoples poor workmanship I'd rather just have myself to blame.
On a side note are MX-5 bolts made of cheese? Didn't take much to snap them and I can't believe I could be undoing bolt wrong!
What next? Other than riding my bicycle to work for the next week
I've drilled a hole in each and tried using my bolt extractors but not enough purchase so I tried drilling the bolts out. Combination of me being rubbish and the drill mean that I've gouged the cover itself. So that needs replacing, no biggie, I can get that part from autolink for £12 ish.
But how to I get it off without damaging the thermostat housing, that's much more expensive and I'd have to take the timing belt off (which I just paid someone to replace, would've been nice if they'd spotted the thermostat gasket was leaking whilst doing the work, they're a well respected 'specialist in these parts).
Note that I'm not shipping this off to a garage again, get fed up of other peoples poor workmanship I'd rather just have myself to blame.
On a side note are MX-5 bolts made of cheese? Didn't take much to snap them and I can't believe I could be undoing bolt wrong!
Edited by Benrad on Wednesday 21st August 12:36
Cheese - yes it seems that way.
If they're broken can you not take the cover off? Soak thread in plus gas for 24 hrs, also any remaining bolts. Use a Stilson/mole type grip on the length of stud, sometimes a few taps with a hammer on the head of the bolt or broken stud help break it loose. If not feasible or it breaks you've little choice but to go back to drill and stud extractors.
When really stuck I've drilled them out to say 1mm less than the diameter of the thread and picked the bits of thread out with a dental pick and then retapped to clean it up. Needs a steady hand and not to be rushed.
If they're broken can you not take the cover off? Soak thread in plus gas for 24 hrs, also any remaining bolts. Use a Stilson/mole type grip on the length of stud, sometimes a few taps with a hammer on the head of the bolt or broken stud help break it loose. If not feasible or it breaks you've little choice but to go back to drill and stud extractors.
When really stuck I've drilled them out to say 1mm less than the diameter of the thread and picked the bits of thread out with a dental pick and then retapped to clean it up. Needs a steady hand and not to be rushed.
Oldandslow said:
Cheese - yes it seems that way.
If they're broken can you not take the cover off? Soak thread in plus gas for 24 hrs, also any remaining bolts. Use a Stilson/mole type grip on the length of stud, sometimes a few taps with a hammer on the head of the bolt or broken stud help break it loose. If not feasible or it breaks you've little choice but to go back to drill and stud extractors.
When really stuck I've drilled them out to say 1mm less than the diameter of the thread and picked the bits of thread out with a dental pick and then retapped to clean it up. Needs a steady hand and not to be rushed.
I'm not sure if the cover is threaded too? Feels that way as the cover isn't budging. If someone could confirm the cover isn't threaded then I'd put a hammer handle up the water inlet pipe to lever it off (it's scrap anyway). If it is threaded then I'd almost be tempted to drive on it for now...If they're broken can you not take the cover off? Soak thread in plus gas for 24 hrs, also any remaining bolts. Use a Stilson/mole type grip on the length of stud, sometimes a few taps with a hammer on the head of the bolt or broken stud help break it loose. If not feasible or it breaks you've little choice but to go back to drill and stud extractors.
When really stuck I've drilled them out to say 1mm less than the diameter of the thread and picked the bits of thread out with a dental pick and then retapped to clean it up. Needs a steady hand and not to be rushed.
Can't actually confirm that but it seems unlikely. If it was threaded it would be on the same thread as the one going into the base. It would never tighten down onto the gasket that way. More likely stuck in place with corrosion and or sealant. Try gentle tapping with a small hammer, initially.
Benrad said:
Note that I'm not shipping this off to a garage again, get fed up of other peoples poor workmanship I'd rather just have myself to blame.
You have my utmost sympathy. I'm in a similar position with my daily driver after bodged work by a local "specialist". I'll be needing a few more bits before I can undo and then correct his work!Good luck.
After soaking with penterating oil overnight give the remainder of the bolts a few sharp taps with a punch and hammer.
Localised heating may work i.e. a pencil gas torch on the ali surround - in theory that expands the ali faster than the steel of the bolt.
Failing that you'll need to drill out to within an ace of the threads to then pick the remainder of the bolt out.
At the risk of incurring the wrath of the mods see this post on ANOther site :http://www.locostbuilders.co.uk/viewthread.php?tid=173087
HTH. Cheers Pewe.
Localised heating may work i.e. a pencil gas torch on the ali surround - in theory that expands the ali faster than the steel of the bolt.
Failing that you'll need to drill out to within an ace of the threads to then pick the remainder of the bolt out.
At the risk of incurring the wrath of the mods see this post on ANOther site :http://www.locostbuilders.co.uk/viewthread.php?tid=173087
HTH. Cheers Pewe.
Edited by pewe on Monday 15th July 10:37
Got the cover off a couple of weeks ago so I've got the two studs showing. Been GT-85ing them daily since then but not a bit of movement.
I think I might push it round to the local independent, fortunately not far with next to no incline. Any more ideas before I do? And are they likely to be able to help!?
I think I might push it round to the local independent, fortunately not far with next to no incline. Any more ideas before I do? And are they likely to be able to help!?
Heat, get them as hot as you can (at least glowing red) then wack wd40/diesel/anything else that creeps on there, may have to do it a few times, wallop the end of them with a hammer, knock them round a bit gently to free the thread as much as possible, then get them hot one last time, let them cool off for a minute or 2 then whack some stilsons on there and wind them out.
Sooo yesterday I took a day off work and cracked on.
~10 hours later I have an engine that runs perfectly (but is making a racket because I left something rubbing.
Just thought I'd document the fix incase anyone googles this in future!
The procedure was rad out, air intake cross over pipe off, aux belts off, timing belt off. Then the camshaft sprokets needed to come off but wouldn't budge (I suspect the aformentioned monkeys either loctited or over torqued them, they're only retaining bolts ffs!)
No problem I thought, I'll take the camshafts out... couldn't get the front bearing caps off (I know they're pretty tricky)
The only reason for taking the sprokets off is to remove a sealing plate which stops oil falling on the cambelt if the camshaft front oil seals go. I got fed up and bent the plate out of the way.
With that I was able to replace the thermostat housing (around £60 from the usual suspects)and reassmble. Except the sealing plate wouldn't quite go back straight and is rubbing on the intake camshaft sproket. Engine runs great and when I get time I'll figure out a way to stop the noise. It'll get me about for now though.
The enthusiasts manual is now covered in oily prints and I appreciate the architecture of my engine must better!
If you've just googled this... good luck, factor in at least a day, make sure you have a breaker bar (I didn't) and a torque wrench and don't forget the o ring for the thermostat housing (get the OEM one)
~10 hours later I have an engine that runs perfectly (but is making a racket because I left something rubbing.
Just thought I'd document the fix incase anyone googles this in future!
The procedure was rad out, air intake cross over pipe off, aux belts off, timing belt off. Then the camshaft sprokets needed to come off but wouldn't budge (I suspect the aformentioned monkeys either loctited or over torqued them, they're only retaining bolts ffs!)
No problem I thought, I'll take the camshafts out... couldn't get the front bearing caps off (I know they're pretty tricky)
The only reason for taking the sprokets off is to remove a sealing plate which stops oil falling on the cambelt if the camshaft front oil seals go. I got fed up and bent the plate out of the way.
With that I was able to replace the thermostat housing (around £60 from the usual suspects)and reassmble. Except the sealing plate wouldn't quite go back straight and is rubbing on the intake camshaft sproket. Engine runs great and when I get time I'll figure out a way to stop the noise. It'll get me about for now though.
The enthusiasts manual is now covered in oily prints and I appreciate the architecture of my engine must better!
If you've just googled this... good luck, factor in at least a day, make sure you have a breaker bar (I didn't) and a torque wrench and don't forget the o ring for the thermostat housing (get the OEM one)
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