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| Author: | drmini in aust [ Thu Oct 06, 2016 12:49 pm ] |
| Post subject: | Re: Blue smoke |
No. More likely worn guides, or valve stem seals. Smallbore heads didn't have proper valve seals, but 1275 ones can be fitted. Replacement guides have grooves fo seals. |
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| Author: | simon k [ Thu Oct 06, 2016 5:09 pm ] |
| Post subject: | Re: Blue smoke |
a head rebuild is probably a good idea, but blue smoke at idle can be caused by glazed bores and worn out oil scraper rings. Even though compression is good, it can still have worn rings Try checking your compression first thing in the morning, and then again after the engine has been driven |
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| Author: | Minicooper4me [ Thu Oct 06, 2016 6:54 pm ] |
| Post subject: | Re: Blue smoke |
Would a wet and dry compression test achieve anything ? |
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| Author: | simon k [ Fri Oct 07, 2016 9:12 am ] |
| Post subject: | Re: Blue smoke |
GuamMini wrote: Okay I will, I thought leaded and unleaded have different components like valve seats, valves only the seats... when modifying a head for unleaded the machinist bores out the valve seat area and fits a hardened insert |
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| Author: | Lillee [ Fri Oct 07, 2016 2:25 pm ] |
| Post subject: | Re: Blue smoke |
GuamMini wrote: simon k wrote: GuamMini wrote: Okay I will, I thought leaded and unleaded have different components like valve seats, valves only the seats... when modifying a head for unleaded the machinist bores out the valve seat area and fits a hardened insert Thanks I assume there is no way to know after is has been installed unless it was installed during ones ownership of the Mini. You have to take the head off and have a look |
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| Author: | awdmoke [ Fri Oct 07, 2016 8:12 pm ] |
| Post subject: | Re: Blue smoke |
Or take out a spark plug and use a $20 endoscopy camera on your phone. Way easier and cheaper. Also good for finding the TV remote under the couch. |
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| Author: | gtogreen1969 [ Fri Oct 07, 2016 8:17 pm ] |
| Post subject: | Re: Blue smoke |
awdmoke wrote: Or take out a spark plug and use a $20 endoscopy camera on your phone. Way easier and cheaper. Also good for finding the TV remote under the couch. I have a $7 ebay endoscope for my phone. It works well for checking bore and piston condition but you need a good mirror attachment on the end to see the valve seats. |
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| Author: | simon k [ Fri Oct 07, 2016 8:39 pm ] |
| Post subject: | Re: Blue smoke |
gtogreen1969 wrote: awdmoke wrote: Or take out a spark plug and use a $20 endoscopy camera on your phone. Way easier and cheaper. Also good for finding the TV remote under the couch. I have a $7 ebay endoscope for my phone. It works well for checking bore and piston condition but you need a good mirror attachment on the end to see the valve seats. especially when they're covered in soot & buildup - seat inserts are really hard to see unless you know what you're looking for and they're clean... |
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| Author: | Lillee [ Sat Oct 08, 2016 8:12 am ] |
| Post subject: | Re: Blue smoke |
I was going to say, endoscope, you guys make it sound so easy! When my head came off the exhaust valve, seat and port was completely covered in 1/2mm of black soot. There's no way you're going to be able to spot a hardened valve seat insert... unless your endoscope comes with a scraper attachment to scrape some carbon buildup  Coincidently a new head gasket is about $20 
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| Author: | drmini in aust [ Sat Oct 08, 2016 10:30 am ] |
| Post subject: | Re: Blue smoke |
The machined edge of the insert. The trouble is, a standard head is often machined there and looks similar. You really need to pull the valves to check inside. |
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| Author: | Lillee [ Sat Oct 08, 2016 11:25 am ] |
| Post subject: | Re: Blue smoke |
drmini in aust wrote: The machined edge of the insert. The trouble is, a standard head is often machined there and looks similar. You really need to pull the valves to check inside. Yeah I thought of that but in theory you could turn the engine over I gear so the valve is open and stick and endoscope in there to see the seat, but as I said it would be covered in carbon as the OP's engine is already blowing blue smoke, it would caked up big time |
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| Author: | Lillee [ Sat Oct 08, 2016 11:27 am ] |
| Post subject: | Re: Blue smoke |
Don't believe me? Here's only a small portion of what came off my head and mine wasn't blowing any smoke or even using up oil. Attachment: IMG_3030.JPG
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| Author: | gtogreen1969 [ Sat Oct 08, 2016 1:01 pm ] |
| Post subject: | Re: Blue smoke |
Here is a before and after of a 12G940 I did on my last car.   Here is a close up of the inserts for the exhaust valves. The seats standout when it all cleaned up but you need a good eye if there is carbon and soot.  I would be looking at pulling the head. It is a pretty easy and cheap job on a mini and you can get so much information about your engine condition from doing it. But getting back to your original question your valve guides are probably worn and the valve guide seals have probably gone hard and are not holding tension on the valve stems. |
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