Propshaft Posted August 16, 2023 Report Share Posted August 16, 2023 I have a 81 standard tr7 I don’t think the head has ever been off would that year of tr 7;have hardened valve seats also the spark plug threaded holes are getting a little sloppy has anyone any experience , knowledge of the insert that can be used thanks Quote Link to post Share on other sites
malcolm Posted August 16, 2023 Report Share Posted August 16, 2023 The information I have come across over the years suggests the following: 1) Brico manufactured all(?) the valve seats for ali headed UK engines (Rover V8, Dolomite/TR7 engines) 2) They were all to the same spec 3) Brico said that the seats are OK for normal use with unleaded 4) US TR7 valve seats are the same as the UK items and the US has used unleaded since around 1980 Hope this helps. Its actually dug up from an old forum post from back in April 2006. I can’t credit the poster as he is long gone and only appears now as a guest… Quote Link to post Share on other sites
Propshaft Posted August 17, 2023 Author Report Share Posted August 17, 2023 Thanks just need to hear from anyone regarding rethreading / thread inserting the spark plug hole Quote Link to post Share on other sites
stuart Posted August 17, 2023 Report Share Posted August 17, 2023 3 hours ago, Propshaft said: Thanks just need to hear from anyone regarding rethreading / thread inserting the spark plug hole I dont know if you still can but you used to be able to buy a kit to rethread, IIRC it came with a tap and an insert to fit in the head. Stuart. Quote Link to post Share on other sites
malcolm Posted August 17, 2023 Report Share Posted August 17, 2023 Looks like you still can. I was keeping quiet as never tried it myself! Quote Link to post Share on other sites
stuart Posted August 17, 2023 Report Share Posted August 17, 2023 (edited) 4 minutes ago, malcolm said: Looks like you still can. I was keeping quiet as never tried it myself! Had to use them a few times back in the day when racing Jaguars, Lag the tool in grease to contain the swarf and then spin it over to expel anything else after and they worked well. Only ever used on Ally heads mind. Stuart. Edited August 17, 2023 by stuart Quote Link to post Share on other sites
RobH Posted August 17, 2023 Report Share Posted August 17, 2023 Looks as though you can get two types, wire helicoil or solid insert. https://workshopping.co.uk/engineering-tools/helicoil-type-products/thread-repair-kits/spark-plug-thread-repair-kits/helicoil-type-spark-plug-thread-repair-kit-m14-x-125mm https://workshopping.co.uk/engineering-tools/helicoil-type-products/thread-repair-kits/spark-plug-thread-repair-inserts/spark-plug-solid-thread-inserts-m14-x-125-x-112mm-pack-of-10 Quote Link to post Share on other sites
stuart Posted August 17, 2023 Report Share Posted August 17, 2023 13 minutes ago, RobH said: Looks as though you can get two types, wire helicoil or solid insert. https://workshopping.co.uk/engineering-tools/helicoil-type-products/thread-repair-kits/spark-plug-thread-repair-kits/helicoil-type-spark-plug-thread-repair-kit-m14-x-125mm https://workshopping.co.uk/engineering-tools/helicoil-type-products/thread-repair-kits/spark-plug-thread-repair-inserts/spark-plug-solid-thread-inserts-m14-x-125-x-112mm-pack-of-10 Ive only used the solid type, I think theyre better in service as they have a small lip on the top so they cant move down. Stuart. Quote Link to post Share on other sites
Peter Cobbold Posted August 17, 2023 Report Share Posted August 17, 2023 The TR7 head is alloy. Usual problem is not the seat inserts but the cam followers wearing away the recess in the head. Quote Link to post Share on other sites
Propshaft Posted August 18, 2023 Author Report Share Posted August 18, 2023 Thanks just need to hear from anyone regarding rethreading / thread inserting the spark plug hole Quote Link to post Share on other sites
Propshaft Posted August 18, 2023 Author Report Share Posted August 18, 2023 Yes one of the reasons I bought this topic up was I set my valve clearances a couple of years ago after about 3 k miles just set them again and mainly the exhaust had closed up by about 8 thou so asking the question about hardened seats thanks for all your replies Quote Link to post Share on other sites
Propshaft Posted October 13, 2023 Author Report Share Posted October 13, 2023 Just completed the RBRR and at least one tappet wants resetting spot on 2.5k miles ago before I started the run Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.