Valve seats

[p.faurie]

Hi guys,
Can any one recommend an engine shop in NE Lincolnshire that can fit some exhaust seats in a tc head, my local garage said they send their head work to some one in Scotland, I'm fairly new to the area,and tried to find local firms on the web etc,but am unable to find some one, I know I could take it further afield,but would prefer to use someone local
Thanks guys

[RichardHawkins]

I was unable to find anyone competent within 100miles of NE Lincolnshire. I had the job done poorly by Coventry Boring and Metalling, and eventually went to Serdi UK in Uxbridge (near Heathrow). Someone on this site said something to the effect that travelling to the far end of the country is nothing compared to the hassle of sorting out incorrect work. I think Rohan, one of our Australian Lotus owners, sends work to the USA to get it done correctly.

J R Hawkins (Richard)

My phone number is in the Grimsby phone book if you want to talk.

[p.faurie]

Hi Richard, thanks for your reply, looks like I've got to go down south , will look you up,I'm in Horncastle, speak soon
Regards Phil

[jono]

Phil,

I've had 3 heads done (valves and seats) by Paul Exon in Coalville, Leicestershire, and they were all good...if you're not in a hurry.

Jon

[alan.barker]

Sorry, silly question but why do the Exhaust Seats need changing. Are they badly recessed or you have cracks between the Exhaust seat and the Sparkplug hole.
Alan

[p.faurie]

Well Alan,it all started as I was trying to sort out oil leaks from the front cover and sump area, i removed the cam cover and realised it appeared I had odd cams (I have a s130) 1 has 2 grooves 1 has no grooves around the sprocket hub, I checked the clearances and they were a little tight, I removed the head and carried on with sorting the oil leaks etc.
The engine runs fine,no smoke I've run it for approx 7 years in my ownership,stripped the head inlet valves look as new, clearances spot on,shim thickness around 80thou,exhaust valves shims below 60thou,removed valves and it appears that the top of the valve stems have been ground down, My thinking was to buy 4 new exhaust valves(which I have) grind them in put the inlet cam on the exhaust side to see if I have a different cam as I don't have a dti gauge ,and if I did I wouldn't know what to do with it.after faffing around swopping cams etc I concluded I need new exhaust seats as I have zero clearance with the new valves, the original valves don't leak but my concern is the thin shims,and I need to get the cams measured to find out what I have,bloody expensive oil leak,I should have let the chassis lub system do its job.

[Mazzini]

Phil,

I've had 3 heads done (valves and seats) by Paul Exon in Coalville, Leicestershire, and they were all good...if you're not in a hurry.

Jon

Funny I've had two engines built by Paul, one was superb the other problematic, I ended up pulling both apart, the machining was excellent, but the valve seats on both engines were awful, I ended up sending them to Nick Stagg to get rectified.

[p.faurie]

Sorry for the ramblings Alan, yes I think seat recession or over cut,
Thanks Jon, looks like I will be travelling.

[alan.barker]

The other possible thing is to get the unmarked cam reprofiled Big Valve which will reduce the base circle of Cam.
This will increase Shim thickness to more than 60 thou.
Alan

[steveh]

Phil,

I've had 3 heads done (valves and seats) by Paul Exon in Coalville, Leicestershire, and they were all good...if you're not in a hurry.

Jon

.

I wish i could say the same , he made a shockingly rough job of mine in many respects .I took it elsewhere after to get it rectified .

[jono]

...I almost qualified my post to say others will disagree!

No interest, just the work he did for me was good... perhaps I've just been very lucky.

The only issue I did have was poor communication.

Jon

[alan.barker]

In all the Years of owning different Lotus i have never had any Valve Seats changed.
However when i had a Ford Cortina Twin Cam and rebuilt the Engine the Valve Shims were thin.
I was looking for more power bhp so i got the Cams reprofiled to Piper FY2. Which killed 2 Birds with one stone.
More bhp + lower base circle on Cams so thicker Shims. I was very happy with the result more power, cost less and no risks of someone bodging with new Valve seats. I changed the Valve Guides of course which is not too difficult.
Alan

[Famous Frank]

While you are on this quest, should you need them, I have brand new NOS Ford valve seats available for $5 US each plus shipping. Pics available.

Either way, I hope you find someone extremely competent! That head is too valuable for someone to use it as a learning tool! Best of luck
Frank

[alan.barker]

If someone needs to fit new steel seats (not old stock too soft) imho the only way . Warm head slowly in an oven + submerge /chill seats with liquid Nitrogen. Never fit using a Press.
If it was me do as i said above fit a reprofiled Cam with smaller base circle, thereby increasing Shim thickness.
I know of several people who have had their Engine Valve seats fall out.
Alan

[p.faurie]

Ok, I've measured the length of the new valves 3.850", original (looks like they have been ground down) 3.800,so my question is, is it recognised practice to grind the top of the valve stem? If so how much is safe,with the original valves (ground to 3.800) I have 57-60 thou thick shims so I think I will need to shave about 60 thou off the new ones to give me around 70 thou thick shims,,would this be ok,as it seems new seats may open a bigger can of worms.
Phil