Author Topic: Lister SR-1 exhaust valve seat regrind question.  (Read 6557 times)

Bablitz

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Lister SR-1 exhaust valve seat regrind question.
« on: October 17, 2010, 05:36:50 AM »
I have some pitting around the lip of the exhaust seat on my head, are there limits to the depth that this can be reground? In a ST manual it says the exhaust valve can be .033" to .045" below the combustion surface of the head. Would .045" be the absolute limit or can I go farther, in order to get past the pitting? It would be a shame to have to junk the head.
Thanks in advance
Bud

listard-jp2

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Re: Lister SR-1 exhaust valve seat regrind question.
« Reply #1 on: October 18, 2010, 11:48:53 AM »
I see no reason why you cannot go deeper than 0.045" (within reason), however when recutting the seat take great care to select a seat cutter that only cuts the seat, and not the surrounding head area.

With care the SR cylinder head can have seat inserts fitted, but you need to be very careful in your selection of  seat inserts, as the design of the ports is such that the seat insert will not be supported around its entire periphery if you bore the seat insert hole too deep.

Bablitz

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Re: Lister SR-1 exhaust valve seat regrind question.
« Reply #2 on: October 21, 2010, 05:30:09 AM »
Thank you, that makes sense
Bud

horsefly76

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Re: Lister SR-1 exhaust valve seat regrind question.
« Reply #3 on: February 22, 2011, 08:35:16 PM »
I have some pitting around the lip of the exhaust seat on my head, are there limits to the depth that this can be reground? In a ST manual it says the exhaust valve can be .033" to .045" below the combustion surface of the head. Would .045" be the absolute limit or can I go farther, in order to get past the pitting? It would be a shame to have to junk the head.
Thanks in advance
Bud

I know this is an old post but there is/was a New Old Stock SR1 Cylinder head for sale on E bay if you need it ($300 ish). I had it saved as I have a SR1 myself
2007 Metro 6/1 Running on Biodiesel (Thank's Sam!)
4 Hp Air Cooled Yanmar Clone
6.5 Hp Kubota EB-300 D
2007 kawasaki KLX 250 Dual Sport
2003 Jetta TDI 5 Spd.
1971 Lister SR1
2 Lister Petter LPA3

dieselgman

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Re: Lister SR-1 exhaust valve seat regrind question.
« Reply #4 on: February 27, 2011, 04:54:52 PM »
I will see about getting the valve data for your SR posted in the White Papers section... it is also possible to replace the valve seats in those, but maybe a better/easier option to replace the head.

dieselgman
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dieselgman

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Re: Lister SR-1 exhaust valve seat regrind question.
« Reply #5 on: February 27, 2011, 10:20:57 PM »
Lister SR1 valve machining specs and limits now posted on micro-cogen White Papers section.

I still could not figure out how to paste into this post.

dieselgman
ALL Things Lister/Petter - Americas
Lyons Kansas warehousing and rebuild operations