31-08-2022, 07:59 PM
(This post was last modified: 04-10-2022, 11:33 AM by Colin Morgan.)
As there was a noticeable drip from the sump whilst the car was in the garage last week, I did a check on how many sump bolts would still tighten 'fully' - turned out that three were 'a bit soft' and two were 'soft'. Seemed (last week) that best course of action was to Helicoil them - so over the weekend put the car high up on axle stands and removed the sump and now have five new Helicoils fitted.
Am in the process (mail strike today not helping) of obtaining a new set of bolts, as some of those I have taken out were decidedly worse for wear - not to say necked. If a bolt snaps off in situ then it is a whole different problem?
Once the bolts and oil are back in, I will know whether or not a bit of extra tightness has helped? From what has been said above, given a couple of the Helicoiled holes aren't blind, further sealing may yet be necessary... will find out in due course.
Update edit: The sump bolts are now tight after Helicoiling those that were weak and the oil is back in. But the sump still drips - possibly because a couple of holes that were previously blind now break into the crankcase following the drilling for Helicoiling - so this now needs some investigation. I get the impression that thousands of other Seven owners have been down this route - stopping drips from the sump perhaps needs a more sophisticated approach - say studs? - as others have spelt out.
Further Update: Turns out none of the Helicoiled holes has broken through - the leak came from two of the bolts not being tightened properly - one that was Helicoiled and one where a new bolt had been substituted instead of stretched one - both were stiff to tighten, felt like there was a risk of shearing the bolts so took it very gently. After ensuring all the bolts are properly tight, there is still a slight drip this evening. The next stage might be to try some sealant or Locktite to improve matters, should this prove necessary?
Update two weeks later: Tightening the bolts did not help. Still dripping seriously enough to need attention. Made a gasket out of 2mm cork sheet to replace the paper one. This was fitted dry (with a cotton loop threaded through the front end holes to help hold it in place) and tightened carefully - just holding the socket drive in the palm of my hand - so probably less than 5 ft pounds torque. It is - so far - leak free.
Am in the process (mail strike today not helping) of obtaining a new set of bolts, as some of those I have taken out were decidedly worse for wear - not to say necked. If a bolt snaps off in situ then it is a whole different problem?
Once the bolts and oil are back in, I will know whether or not a bit of extra tightness has helped? From what has been said above, given a couple of the Helicoiled holes aren't blind, further sealing may yet be necessary... will find out in due course.
Update edit: The sump bolts are now tight after Helicoiling those that were weak and the oil is back in. But the sump still drips - possibly because a couple of holes that were previously blind now break into the crankcase following the drilling for Helicoiling - so this now needs some investigation. I get the impression that thousands of other Seven owners have been down this route - stopping drips from the sump perhaps needs a more sophisticated approach - say studs? - as others have spelt out.
Further Update: Turns out none of the Helicoiled holes has broken through - the leak came from two of the bolts not being tightened properly - one that was Helicoiled and one where a new bolt had been substituted instead of stretched one - both were stiff to tighten, felt like there was a risk of shearing the bolts so took it very gently. After ensuring all the bolts are properly tight, there is still a slight drip this evening. The next stage might be to try some sealant or Locktite to improve matters, should this prove necessary?
Update two weeks later: Tightening the bolts did not help. Still dripping seriously enough to need attention. Made a gasket out of 2mm cork sheet to replace the paper one. This was fitted dry (with a cotton loop threaded through the front end holes to help hold it in place) and tightened carefully - just holding the socket drive in the palm of my hand - so probably less than 5 ft pounds torque. It is - so far - leak free.