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Auzeras

Replace this piston?

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So over the last few months I've been finally rebuilding my M30 head, cam rebuilt and welded up by franklin cams (can't recommend them enough) and the head is being done at Headmaster In Wellington. The other day headmaster called me and said when they pulled the valves out one of the exhaust valves was badly bent. I was surprised as the engine had run okay up until the day I parked it up, none the less I decided to investigate a little more closely... 

 

Turns out cyl 1 high fived a valve at some point, I rotated the engine over and there's no scoring on the cylinder walls, a little wear but no worse than the other cylinders. Honing is clearly present 93% of the way around, the rest a little more polished but still okay. Looks like any debris from the impact vacated the engine without scratching anything up.

 

I know the real answer is replace that piston.. But I'll ask anyway, do you think that damage is worth leaving in there? It's a daily driver not a race car. Piston comes cleanly up to the top so rods aren't likely bent. Bearing may be damaged, I'll look at that when I get the oil pan off, rotates smoothly. Just give it a little peen around the edges, pray to the gods of oil and leave it?  

 

IMG_20170113_075851.jpg

IMG_20170113_075845.jpg

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I would say it will be fine .

but I do have a set of 10;1 c/r pistons if you want to upgrade ;) 

but you will be pulling whole engine apart and rebuild everything by the time you do that .

did you still want that new valve ?

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Thanks BM World, the guys at headmaster agreed they reckon it should be okay. I'd upgrade if I could - we all know that ;) but for now this M30 is just going to be hauling from A to B. Far too much work to go full out rebuild right now!

 

I rang your shop a few days ago, parts department said the only had valves for M20's? At this stage I'm waiting on a new valve from a supplier in Australia. Headmaster in Wellington are going to combine shipping with another order, it was about $25 + P&H  so if you do have a similarly priced unit in stock I can pick it up and cancel the Aussie order no problem.

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6 hours ago, Auzeras said:

Thanks BM World, the guys at headmaster agreed they reckon it should be okay. I'd upgrade if I could - we all know that ;) but for now this M30 is just going to be hauling from A to B. Far too much work to go full out rebuild right now!

 

I rang your shop a few days ago, parts department said the only had valves for M20's? At this stage I'm waiting on a new valve from a supplier in Australia. Headmaster in Wellington are going to combine shipping with another order, it was about $25 + P&H  so if you do have a similarly priced unit in stock I can pick it up and cancel the Aussie order no problem.

no one rang me ?? 021433600 im the only one that answers the phone

what number did you ring ?

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On 1/15/2017 at 6:27 PM, BM WORLD said:

 

what number did you ring ?

Obviously the wrong number :rolleyes:

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hey come on Mac, we've been waiting for an update about the 750D on your other thread...

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Yea, spill the beans MacB)

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