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Title: Spark plugs won\'t thread back in
Post by: Tim_B on July 04, 2010, 07:43:09 PM

Help :2Confused

This may sound daft but 2 of my spark plugs won\'t go back in. Bottom two are fine, but top 2 I can\'t get in at all :3Confused
They just don\'t seem like they want to thread back in at all, which is bizarre as they came out fine. Presumably if the thread is destroyed its an absolute nightmare?
Any thoughts gratefully received

Title: Spark plugs won\'t thread back in
Post by: m1tch on July 04, 2010, 07:54:03 PM

Is there any muck on the threads? Might just be the angle you are trying to thread them in. Cross threading BAAAAD lol

Title: Spark plugs won\'t thread back in
Post by: rx-dave on July 04, 2010, 07:56:04 PM

Are the threads on the plugs ok and are you sure you are at the correct angle? If they are intact i doubt you\'ve knackered the internal thread in the engine itself. If they are damaged then i\'d presume it\'s an engine out job :Hammer Fingers crossed for you!

Title: Spark plugs won\'t thread back in
Post by: Tim_B on July 04, 2010, 08:22:12 PM

Threads on plugs ok as I have the same problem even when I swap the plugs around. Think the angles OK as I\'ve been trying to get them in for hours :Grrr
feels like it could be muck on the engine threads but not sure how best to tackle these.

Pushed it in the garage - enough for 1 day :2Confused

Title: Spark plugs won\'t thread back in
Post by: Prof on July 04, 2010, 09:34:49 PM

The hole into the engine from the top plug is quite small - so a soft cloth wetted with some spirits rolled round the whole gently should get a lot of the crap out of it with minimal risk of pushing crud into the engine. Just don\'t pack it in hard when cleaning.

You can get plug taps for chasing the threads - M14 plug I think you can search for - it\'s a fine thread.

I\'d try cleaning the threads out first, then go for the tap chaser 2nd.

Title: Spark plugs won\'t thread back in
Post by: Tim_B on July 05, 2010, 05:48:00 PM

Thanks I\'ll give it a go

Title: Spark plugs won\'t thread back in
Post by: marcusd666 on July 07, 2010, 12:13:11 AM

Sorry to hear about this Tim, Hope you get this sorted for the 7 7 meet

Title: Spark plugs won\'t thread back in
Post by: clive on July 07, 2010, 10:27:33 AM

I helped a guy sort his RX-8 a few weeks back with the same problem,

As Dave suggests you really need a No1 tap running into the hole rather than persevering with a plug and bruising the thread more.

I put a small 1/4 drive socket on the end of the tap to wind it in and out as you will find theres not enough room to use a tap holder

I use a heavy grease on the tap which means that most of the swarf sticks to the grease then once you know that the plug screws in, remove it and spin the engine over to blow out any remaining swarf
Hope this helps

Mazda Rotary Club

General => General Technical => Topic started by: Tim_B on July 04, 2010, 07:43:09 PM