Lister Engine Forum

How to / DIY => Engines => Topic started by: Bablitz on October 17, 2010, 05:36:50 AM

Title: Lister SR-1 exhaust valve seat regrind question.
Post by: Bablitz 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

Title: Re: Lister SR-1 exhaust valve seat regrind question.
Post by: listard-jp2 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.

Title: Re: Lister SR-1 exhaust valve seat regrind question.
Post by: Bablitz on October 21, 2010, 05:30:09 AM

Thank you, that makes sense
Bud

Title: Re: Lister SR-1 exhaust valve seat regrind question.
Post by: horsefly76 on February 22, 2011, 08:35:16 PM

Quote from: Bablitz 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

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

Title: Re: Lister SR-1 exhaust valve seat regrind question.
Post by: dieselgman 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

Title: Re: Lister SR-1 exhaust valve seat regrind question.
Post by: dieselgman 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