Well the Mini decided to blow out plug #2. Now we got it fixed with a helicoil but I am unsure of the reliability of it the fixing of the head. Has anyone put on a lot of miles since having their plug blown out and fixed by any method other than replacing the head? The mini gets drove 50 miles round trip for work a day and wondering if I should keep it or trade it off it's a 2005 R53 with 103xxx on it.
I bought an R50 with blown number 2 which I found out later had been repaired. In the end I bought a used R53 head
If it was done right it will last as longer than the original threads......I would not worry about it. The reason plugs come undone is either they were over-tightened and stripped the threads or they were not tightened properly, allowing them to work loose. Most of the ones I've seen have been due to the latter......
Welcome, thanks for joining Motoring Alliance, the FUN and Friendly MINI Community. This is not terribly uncommon. Many have used the helicoil route with no problems.
Ok good deal. It's the GFs car and she is deadly afraid of driving it now after it just got fixed today. She thinks that she is the reason it broke and after I told her no it wasn't her it's just a design flaw and the fact that the plugs weren't seated properly. Sounds like we will be keeping it then and keep on motoring
Haha very funny Nathan. Actually it was before the race car days That's how I got the mini cheap off eBay. Mine was done with a insert which fell out with the plug. If your job was done correctly it should be fine
Ok sorry that might be a bad choice of words but I know of many aluminum block heads that are not prone to the issue of the heating and cooling of the block allowing for the expansion on the aluminum causing plugs to go loose and cause this issue. This is the first aluminum head vehicle that I have ever heard of people recommending retorqing the plugs every time that you change the oil. I have known to check torque on them after a heat cycle in an aluminum block but not consistently over and over again. But all things said I'm new to the mini ways and there are many things that are highly different than American or even Japanese motors. So thanks for the reassurance that I can tell her to keep on driving it like she stole it.
Well, as I said before if the plugs are installed properly they don't come out. You do not have to re-torque them - ever - if you install them correctly. There is nothing wrong with the heads, nothing different about them that requires any sort of different procedure than any other aluminum head. But there seem to be a few people who don't understand the right way to install the plugs and that's what causes the problem. Then their misunderstanding gets reposted all over the net as fact. Every one of these I've ever heard of that popped out were shortly after the plugs had been changed - improper installation. I've never heard of a plug installed by the mfr that came out. It's pretty simple, tighten them down till they crush the washer, then torque to spec. Done. Personally I've never had a plug come loose on any head, aluminum or otherwise in the 50+ years I've been putting them in internal combustion engines. Not one. And many, many of those were aluminum heads, including MINIs...... I'll bet the fellows who run professional shops here don't have them pop out either.....
The plugs on it where changed 15k ago by a professional. I honestly have never heard of anything like this happening in vehicles either that's why I was so taken back by it all. Thanks for your help
I agree. Never had the problem myself. But I've just done it by feel - which is not very good, or accurate. What is the proper torque specs for the spark plugs for our MINIs?
Frankly, that's how I do them too.....crank it down till the washer is fully compressed, then turn it till it's tight - that's my method. Hasn't failed me yet and like I said, over 50 years now.... jrahn I don't know what to tell you, but there's nothing magical about Mini heads, and there are plenty of examples of the same problem on lots of other car forums too.....
This happened to me when I first got my mini... driving along then sounded like a huge exhaust leak and no power.. got it off the road and saw the boot on #2 a little higher than the other 3. LUCKILY it just worked it's way out... retorqued it when I got home as it was vacuumed hose tight since that's all I had in the car at the time to put it on but it held till i got home like 15min later.. it's been fine since over a year now..
spark plug threads.. We have found the torque is the key in most of the cases. However we have also found that when the chambers crack, MOST of the time the crack goes into the threads. SO when you get the Heli-coil or Timesert installed make sure the shop LOOKS for the cracks and then make the adjustments . see the attached. Hope this helps..
Great info man! Luckily I know ours wasn't cracked as I was there with the tech while he was doing it since he is a good friend of mine. Plus on a side note the mini might be getting some racecar upgrades since it finally snowed here so a new ported and polished head might be one of them.