Valve seat inserts and E10 fuel

[Andy8421]

If you are considering replacement valve guides look into fitting phosphor bronze liners.
Results in much less valve seat work.

Any info please on typical costs for fitting PB valve guide liners?
Thanks
Malcolm

Malcom,

I dealt with these guys:

http://www.gosnays.co.uk/acatalog/_DFL__COATED_BRONZE_BULLET_GUIDE_LINERS.html

The liners themselves are quite cheap, and my Son's guides were already the right size to accept them. I made the broach myself on my lathe, so the total cost to me was just a few £. I recall Gosnays would do the whole job for you, and return a refurbished head. I have no idea how much this cost, but I am sure if you call them they will quote. I have no idea of the quality of the work they do.

Andy.

[friedy]

I'm about to get my guides sorted and been looking around, im in Essex. I also found the K inserts and think they sound a good idea. There are another 2 company's close, Thurston engineering in Ongar who can do the K inserts or replace, or Vulcan Engineering near Brands Hatch they will only replace the guides, both cost about the same, sort the guides and recut seats just over £200 +vat. I don't know anything about their quality of work, but both seen to have done a lot of twink heads. I'm going to try Thurstons because it's a little closer to me.
Alan.

[englishmaninwales]

I'm about to get my guides sorted and been looking around, im in Essex. I also found the K inserts and think they sound a good idea. There are another 2 company's close, Thurston engineering in Ongar who can do the K inserts or replace, or Vulcan Engineering near Brands Hatch they will only replace the guides, both cost about the same, sort the guides and recut seats just over £200 +vat. I don't know anything about their quality of work, but both seen to have done a lot of twink heads. I'm going to try Thurstons because it's a little closer to me.
Alan.

Alan please let us know how you get on.

[512BB]

' I've been in workshops where this has been done (warm head, liquid nitrogen for guides) and they still needed knocking in so I guess they didn't get the head hot enough and guides cold enough !'

I am surprised you make this comment Alastair. Of course they still needed knocking in, they should be a very tight interference fit in the head. And for 'warm', when fitting or removing valve guides, bearings etc in alluminium, read bloody hot. If the metal feels all lovely and warm to the touch, you haven't got it hot enough. If guides of whatever metal, just plop into an aluminium head after it has been heated, they are going to move when the engine is being driven hard. They need to be pressed or tapped into the head with some force. Then you know they are a good fit and not going to move when the head gets very hot in service.

Leslie

[rgh0]

Do the maths on expansion of the head hole and shrinkage of the guide its not that hard... why speculate ?

The hard bit is every time you heat the head you shorten its life

cheers
Rohan

[alan.barker]

+1 a little calculation and meaure to see if you need oversize Guides.
On one of my cars a 1978 TVR 3000S the Essex V6 has "K" Inserts fitted by Burtonpower no problem.
Alan

[avro]

Over the years l’ve fitted K-Line bronze guide liners to many classic cylinder heads but would not fit them to the Lotus Twin Cam head.
With cylinder heads such as the Ford Crossflow where the valve runs directly in the head casting its a very straightforward and relatively easy operation as the guide liner is supported throughout its whole length by the casting which is important when you come to the last stage of fitting guide liners. ( The broaching )
With the Lotus head the valve guides protrude into the ports by some way and the inlet guide has a taper to the end making it rather thin walled and weak.
Once the liner is fitted and cut to length the last operation is to broach the liner to size with a selected ball broach.
This will leave the correct valve to guide clearance. The guide liners have an internal interrupted spiral groove in them and when you drive the ball broach through the liner it displaces the soft material of the liner into the spiral grove.
This operation takes a certain amount of force and with the Lotus head there is a very high risk of the guide
cracking where it is unsupported by the head casting within the port area.

Alan on a previous post mentions Vulcan Engineering. This company has specialised for many years in the machining and overhaul of Ford and Lotus Cylinder heads and he mentions also that they too will not fit guide
liners into Lotus cylinder heads.

Nick

[englishmaninwales]

Thank you for your expert view on the risks associated with fitting K Line liner inserts to the Twin Cam, Nick.
(With apologies to the OP for taking the thread off topic).
Malcolm

[promotor]

' I've been in workshops where this has been done (warm head, liquid nitrogen for guides) and they still needed knocking in so I guess they didn't get the head hot enough and guides cold enough !'

I am surprised you make this comment Alastair. Of course they still needed knocking in, they should be a very tight interference fit in the head. And for 'warm', when fitting or removing valve guides, bearings etc in alluminium, read bloody hot. If the metal feels all lovely and warm to the touch, you haven't got it hot enough. If guides of whatever metal, just plop into an aluminium head after it has been heated, they are going to move when the engine is being driven hard. They need to be pressed or tapped into the head with some force. Then you know they are a good fit and not going to move when the head gets very hot in service.

Leslie

Thanks Leslie, I was being diplomatic in my response regarding having to still press/knock the valve guides in, and I'm aware the temperature of the head should be above 100 degrees C and no more than 150 degrees C (max) when doing so!

[Craven]

If anyone is still interested in the valve guide sleeve option this YouTube clip may be of comfort.
https://www.youtube.com/watch?v=MJ8AnUKANpA

[Fourducs]

I am a new owner and just checked valve clearances for the first time on my 1969 Elan + 2 non Federalized engine. Engine #21117. The inlets were all within the workshop manual spec. of (.005/.007in) The exhausts were all tight at .007in. vs. the .009/.011in. specified in the manual "from engine LP.9952." I am assuming this means engines numbered after 9952 such as 21117 require the .009/.011 clearance. The fact that all the exhaust clearances are the same and that they are right in the middle of the spec. range for the earlier engines makes me think they were deliberately set there. Anybody care to comment? Supposedly the car had a valve job at some time in its history, but I have been unable to determine exactly what was done.