Author Topic: Oil in cylinder  (Read 1539 times)

0 Members and 1 Guest are viewing this topic.

mrsumner

  • Newbie
  • *
  • Posts: 10
  • Karma: 0
Oil in cylinder
« on: June 15, 2020, 05:12:43 PM »
Sudden oil leak into one of the cylinders in my 1991 126 bis.Not feeling good about it but could it be something that members have come across and a simple fix will rectify the problem without having to have the engine rebuilt.I do the very basic repairs and maintenance jobs on the car but internal engine stuff is way beyond me!!
Any thoughts out there?

Pete126

  • Administrator
  • Super Member
  • *****
  • Posts: 3369
  • Karma: 35
  • Location: West Yorkshire
Re: Oil in cylinder
« Reply #1 on: June 16, 2020, 07:44:05 PM »
If it's just started doing it and is overheating, check under the oil filler cap for condensation/water (cream gunk) if so do a head gasket test as that's the most common fault.
Pete.      il cavallo piccolo

ChrisRLewis

  • Administrator
  • Super Member
  • *****
  • Posts: 1709
  • Karma: 25
    • Club126uk
  • Location: Swansea, UK
Re: Oil in cylinder
« Reply #2 on: June 17, 2020, 10:18:29 AM »
How do you know you have an oil leak in one of the cylinders?

mrsumner

  • Newbie
  • *
  • Posts: 10
  • Karma: 0
Re: Oil in cylinder
« Reply #3 on: June 17, 2020, 08:33:42 PM »
When I took the plugs out and turned the engine a mixture of water and oil came out of one of the cylinders.After further research and talking with other people who know more about engines than I do I am coming to the conclusion that the cylinder head gasket has gone.I hope that this is the case as otherwise something more internal in the engine has failed which would probably mean the engine is caput in which case my  lovely bis has come to its final resting place!!I could not afford an engine rebuild so would have to sell to the best bidder.Have had the bis since 2001,only done local miles and generally in the summer months,have regularly serviced it and replaced many original parts-all catalogued.It is also in perfect structural and cosmetic condition.Let's hope it is just the head gasket!!   

Pete126

  • Administrator
  • Super Member
  • *****
  • Posts: 3369
  • Karma: 35
  • Location: West Yorkshire
Re: Oil in cylinder
« Reply #4 on: June 18, 2020, 02:13:36 AM »
You can change the head gasket without taking the engine out but you’ll need to check the heads not warped if it is it will need skimming
Pete.      il cavallo piccolo

mrsumner

  • Newbie
  • *
  • Posts: 10
  • Karma: 0
Re: Oil in cylinder
« Reply #5 on: June 19, 2020, 09:55:50 AM »
I am hopeful that the problem is only to replace the cylinder head gasket BUT I have visited my local engine  restoration specialists in Blackburn who point out that the cylinder head bolts attaching the head to the engine block are susceptible to shearing when taking them out.Apparently a small section of each bolt has been in contact with coolant and will have weakened.If this happens the end of the bolt will remain in the engine block and will have to be drilled out,the engine having to come out of the vehicle for this to be done.Apart from all this I can't find any supplier of a bis cylinder head bolt kit.Has anyone out there taken the head off a bis and/or experienced any problems with the bolts?

ChrisRLewis

  • Administrator
  • Super Member
  • *****
  • Posts: 1709
  • Karma: 25
    • Club126uk
  • Location: Swansea, UK
Re: Oil in cylinder
« Reply #6 on: June 19, 2020, 10:22:19 AM »
The Bis uses cylinder head studs with nuts and not bolts. Don't think that there are many issues with these engines stripping the threads, but helicoil kits are available if the worst does happen. Just take care when tightening the cylinder head nuts, use an accurate torque wrench and tighten in the correct stages. May also be worth getting a replacement copper cylinder head gasket which are less prone to failing.

I am sure that other forum members will give more advice.

mrsumner

  • Newbie
  • *
  • Posts: 10
  • Karma: 0
Re: Oil in cylinder
« Reply #7 on: June 19, 2020, 12:19:05 PM »
Many thanks for your info.Do you have any details of how to tighten the nuts in the correct stages?

ChrisRLewis

  • Administrator
  • Super Member
  • *****
  • Posts: 1709
  • Karma: 25
    • Club126uk
  • Location: Swansea, UK
Re: Oil in cylinder
« Reply #8 on: June 19, 2020, 02:10:13 PM »
Also I would get the cylinder head checked for any warping etc. and also replace the valve oil seals.

mrsumner

  • Newbie
  • *
  • Posts: 10
  • Karma: 0
Re: Oil in cylinder
« Reply #9 on: June 19, 2020, 04:02:08 PM »
Wow-that's great.Many thanks.