SS is actually worse, it rounds off and snaps much easier than a basic 8.8 grade fixing.
The screws, whilst they ‘look’ like POZI or Phillips will more than likely be JIS ones.
Barrie
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Agree I don’t think they are pozidrive I flattened the end of a small size 1 pozidrive but had already rounded the rear ones so lightly hammered in a small torx head and managed to remove them quite easily.
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It wasn’t so much about rounding off but more about removing and refitting the screws without a straight line of sight for a screwdriver. It’s easy enough to shorten an allen key to approach from the side or use a 1/4" drive hex key on a flex attachment. Because they are steel in aluminium a bit of antiseize and not overtightening would also help
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Agreed on not using stainless to replace high tensile bolts but I’ve never rounded a stainless fastener and drilling stainless fittings on my boat is seriously difficult, even with cobalt steel drill bits.
I do get marine grade fasteners from a chandlers though and they are much harder than Ducati fasteners, which are generally regarded as being made of Italian cheese.
Perhaps Mazda fasteners are made of tougher stuff…
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Drilling SS is not trying to use a screwdriver with it, they are totally different things. Grade dependent you will round off or snap an SS fixing very easily, you’ll have real trouble drilling it especially if the drill slips a little and/or is the slightest bit blunt.
It work hardens in a second, a bit of slip on a drill bit to make it blue and that’s it, you might as well be trying to drill a piece of granite with a carrot.
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Try drilling Inconel bolts out…now thats a challenge !
Yeah i’ll steer clear of that thanks, machining SS is bad enough!
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Going on 2 years now and mines been fine since.
I thought I had a problem with my EGR valve, it was diagnosed after I fitted a new battery and rebooted the engine warning light, that the problem lied with the EGR valve.
Got it it diagnosed at Total MX5 Barry by Mark.
Used his diagnostic machine… NO ISSUES, the engine lacked power and was flat going up hills.
After some thought, I realised I’d filled it up previously using E10 not E5!
On the next fill up used E5…… it runs like dream again !!
Mines a 2008 1.8 NC, despite whatever Mazda say, stay with E5!
And thanks Mark !!
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Just to add to some of the previous comments the EGR valve on my 2010 Miyako (only 17k miles from new) was throwing the fault code and despite resetting it several times as soon as the engine reached full working temperature it came back on. The engine was running perfectly and after reading the posts above, I figured it was not a faulty valve but an electrical fault in the stepper unit. I stripped it down and swapped the electrical stepper unit over from a new EGR valve to save the aggravation of trying to remove the body of the main unit from the engine. Took me about an hour altogether and nothing difficult to do just a bit fiddly and cramped at times but saved a load of cash over taking it to a dealer to be repaired. Used a Nike step up box to gain a bit of height to make reaching across the engine bay a bit easier. Total cost circa £80 for the brand new Ford EGR valve(but only used the steeper unit off the top of it). Definitely worth doing yourself. Thank you for the detailed information on how to access it. Much appreciated.
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Brilliant post DannyW. Thank you for taking the time to post this. I have added some further comments below.
Is there a correlation between EGR issues and poor quality fuel, or stop-start driving?
Good question but mine has only been ran on Esso super unleaded for 4 years and is generally used for longer runs with plenty of spirited driving. The valve itself was spotless and not gummed up like some I have seen. I suspect the failure is more to do with electrical gremlins but who knows.
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I wondered if the actuator burnt out when the valve became clogged and hard to move. Obviously not, then.
It seems a long time since I started this thread and I’m happy to see that members have been helped and have improved the knowledge base. The identical EGR on the Mondeo doesn’t appear to have the same problems. I suspect the unreliability of the MX5 EGR is heat related; the Mondeo is in the centre of the engine bay in the direct air flow from the front grille whereas the MX5 EGR is in a confined area where it doesn’t get much cooling.
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I think you might be right. The valve in mine was absolutely spotless (it did get revved regularly) and not gummed up like on some cars. I think heat soak from the engine after driving has probably damaged it. I meant to get an electrical meter before removing it to test the resistance but had to swap it in a hurry as I was part exchanging the car for another one. I still have an MX5 so the knowledge gained is useful but I don’t want to have to swap another in a hurry.
Hi all - just doing my stepper motor now and got to the very end of the process but having a tough time getting to the 2 screws at the back of the stepper motor.
Any advice/ideas on how best to get to them please?
Don’t want to go too heavy/clumsily handed and round the damn things off!
Thank you!
Might be worth investing. In a long screwdriver. I’m guessing that your issue is yous is too short.
https://www.machinemart.co.uk/p/laser-1797-phillips-screwdriver-ph2-x-450mm/
Something like this but maybe not that long.
Or is it something else?