Joined: Aug 2017 Posts: 158 Threads: 51
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Hello all,
Just giving the top end of my engine some attention, and my exhaust valves are well past their best and will need replacing. My inlet valves appear to have been replaced more recently, and are the later pin type, which I believe are incorrect for my car.
Are there any advantages or disadvantages to either type? Aside from being incorrect for the year, the pin types look like a lot less effort to fit compared to the fiddly cotters, and there doesn't appear to be any difference in terms of cost. I'm assuming the spring cups are specific to each type as well?
Any thoughts or advice much appreciated as always
Joined: Aug 2017 Posts: 3,215 Threads: 100
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Location: Darkest Bedfordshire
Yes the spring cups are specific to each. No matter really, I have mixed types in my present engine (exhaust are one type and inlet the other). On balance I prefer the collet type if only because they are easier to retrieve if you drop one (and less likely to end up in the sump).
Joined: Aug 2017 Posts: 1,808 Threads: 99
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hi rupert,
i dont know if there is much advantage on a standard engine.
personly i dont like the way the pin type wear a groove in the cup, it makes me feel they are mot the best way of doing the job.
also when people supply new pins, they dont seem to know what material the originals were made of. so what are they supplying.
also is longevity of supply, everyone gets collet type made first. as a supplier myself i dont even buy stocks of pin type. as its twice as expensive to hold both types in stock.
tony
Joined: Dec 2017 Posts: 1,132 Threads: 66
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Location: Nottinghamshire. Robin Hood County
Car type: Austin Ruby Mk1 1935
My engine has the pin types In 20 years I have only had one problem when a pin sheered making that valve useless as it should not close. I have worked on cars with collets but not 7s. There is little difference in fitting. One thing on the point of pins yes they do wear a groove in the stepped washer.
John Mason
Would you believe it "Her who must be obeyed" refers to my Ruby as the toy.
Joined: Aug 2017 Posts: 1,667 Threads: 38
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Location: Malvern, Victoria, Australia
From Bill Sheehan,
Unable to know if original, but my Speedy engine had the cotter types fitted.
The engine was in the pin type era, so interesting to know if there was a good reason to be different.
Cheers, Bill in Oz. i
Joined: Aug 2017 Posts: 2,748 Threads: 31
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Location: Auckland, NZ
The pins are stressed by wide clearance, over strong springs and revving to valve bounce
Joined: Oct 2017 Posts: 1,392 Threads: 45
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You have to be careful fitting the pins to make sure that they are central which can be fiddly.
Joined: Aug 2017 Posts: 158 Threads: 51
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Thanks all, doesn't sound like there's any particular advantage of switching to the pin type then.
I've recently invested an entire £7 on a phone connected endoscope which has already made things a lot easier with the engine still in the car - I'm hoping it'll make refitting the cotters a bit easier as well!
