Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

Stripped hole on engine case!!

Discussion in 'Technical and Troubleshooting Torque' started by rodgonzbea, Dec 1, 2009.

  1. :censored::censored::censored:Good afternoon, dear people... I need your advise.. I have an 85 Yammy SRX, slowly looking better as ive been fixing it up.. anyhow, did an oil change, changed filter, few days later ai noticed a little oil seeping from the oil filter cover (this model has the filter on the r side of the engine, just above the hole for topping up). I thought id check the bolts as i did not tighten them that hard as i have destryed some bolts in the past.. maybe a little more.. really i was retarded bcause even though it didnt have a gasket when i pulled it out, it wouldnt have hurt it to put one... anyway three bolts, two long on top, one short on the bottom.. as im looking at it and retightening the top right....yeap..screw goes loose.. :censored: i slowly pull it out and the screw thread is intact but the thread is on it.. so i stripped the hole.. now.. one advice was to put a helicoil in it.. cant find a helicoil kit so far.. could i retap a thread.. or stick a self tapping metal bolt just a little bit thicker than the original? or would that crack the case?? if i went to do that, would i have to warm the engine up (ie run it for a bit) so the metal gets softer?

  2. Drill it out and tap a new thread into it, The next size bolt upwards.
  3. Thank you sir.. that i can do with what i have...
  4. Deadman's solution sounds good if there is enough metal to drill out. If not, you can find helicoils in any nut and bolt shop.
  5. Supercheap have a thread replacement kit, while you're there, pick up a torque wrench & use it! Might not have helped in this case, but it's better safe than stripped!
  6. There is a product that is like a putty that claims to be stronger than steel. You put a release compound on the bolt and coat the putty on, then screw it in.

    It recreates the thread.

    My experience is it is not as strong as steal. You wouldn't use it where the bolt has any loading.

    You cna get it at repco etc

    Still I'd go the Helicoil myself.
  7. If you're going to cut a thread be very careful that absolutely NO swarf from the cutting goes into the oil where you can't get it out. Changing the oil afterwards is not sufficient insurance.

    Helicoil IMO.
  8. You own a 24 year old Japanese motorcycle. You need to find a helicoil kit and learn how to use it because this won't be the last time you require it.

    A little mechanical sympathy re gaskets and bolt torques would not go amiss either.
  9. mmm... maybe i should go for a helicoil kit....(y) so far is holding with a brand new high tensile of the same size, till i can get to the shop..leaking is minimal.....sux though when one the high points of the engine was that the case was bone dry.. I kno its an old bike.. but man its nice to ride!! Anyway..thanx a lot for the advice!!!
  10. Tap that out baby.
  11. The trouble with tapping out to the next size up is that, even if you've enough metal, you end up with exactly what you had before; a thread cut in cheese which will wear out rapidly and leave you with exactly the same problem not so very far down the track. Not to mention the pain in the arse factor of now requiring two spanner/key sizes to change the oil filter.

    A helicoil gives you a steel thread, which won't wear out, which is important for something like an oil filter cover which is being removed regularly (it is being removed regularly isn't it?), with the added bonus that the bolts remain standard.

    Frankly, bolts into alloy threads are shithouse from an engineering point of view (they should be studs and nuts), but the unholy alliance of stylists and bean-counters has ensured that almost everything is held together in this horribly sub-optimal fashion.
  12. +1 to patb post

    don't just tap a new thread as same thing will happen over time
  13. Makes perfect sense, thanks Pat. Will file that away for later (30yo kawasaki aluminium has held up so far with just one failure on my watch on a part I had to replace anyway, but you never know).

  14. But even using a (an?) helicoil requires drilling and tapping a new thread for the insert. I agree tho', it's the best solution. I'd also add that an application of some anti-seize compound on all steel-into-alloy is a nice bit of insurance against any dissimilar-metals reaction.

    You won't regret having a few sets of helicoils around if you have an older bike ;-)

  15. Agreed that a helicoil still needs enough meat around it to work.

    Also agree about anti-seize, although it's worth being cautious as the lubrication can allow the bolt to be overtorqued. Strictly speaking, copper based compounds shouldn't be used on aluminium, but I've never had a problem. Anything else is expensive or hard for amateurs to find. I've got a small tub of (IIRC) nickel based stuff that is theoretically better, but I'm not sure if it really makes a practical difference.

    Here in Australia, I'm less concerned about corrosion (which was a major problem in my previous life in the UK) and more concerned about mechanical wear if the bolt is removed and replaced frequently.
  16. **** i hate that. i did that to a rocker cover once. tried everything. easy outs ect.

    eventually i gave up as my ability to tap couldnt be better than my ability to get the snapped bolt out.

    didnt leak once in 10,000kms.

    i snapped a few bolts in that old bike... now im super carfull when tightening ;)
  17. I have some of both, but like you, I find they both seem to work equally well. Got them from the local nut & bolt guys you see in most of the industrial estates.

    I've come across too many badly seized and corroded screws that have sat for years not to use this stuff. For the 10 seconds it takes to apply, it's good insurance I reckon. I don't want some guy years down the road thinking I didn't respect my bike. Been there, done that ;-)

  18. Too late for me. I'm well known for grinding vehicles to financially worthless powder :demon:.