Excellent work. Knew you'd fettle it!
Thats promising news Richard!
"Merlins always drip oil, when they don't....worry!"
One of our newer members (Lee Thorn) has been hard at work starting a new website for WR963, so you can find out all about what we're doing on there.
It's only in its early stages, but if you fancy a peek, it can be found at
Web site is looking very nice, it should be a good advert for the project. Always good to have focal point for anyone interested in the aircraft. Web sites are so good for giving information and generating interest. Can I just ask that the text is either passed through a spell checker or someone reviews it, there are a number of errors and it detracts from the message. Please accept that remark as it it meant, not critical but intended to be helpful.
could always put my pic under the "honourary useless southern member"
Spot on website though mate
Last edited by Nashio966; 18th December 2010 at 13:12.
I haven't seen your resignation in writing yet - and thats assuming I accept it.. (You got me into this, so if I stay, you stay! )
E-mail me a picture that you're comfortable with and we'll put you on there mate. You're still part of things however much you protest.
lmao, dont worry about it Rich, wouldnt wanna ruin the website with my ugly mug :diablo:
Sat 8 January
Today was our first day back working on WR963. We were quite happy to find that she has made it through all the bad weather with minimal water ingress into the aircraft - fuselage, structures or fuel tanks. The cleaning and sealing has started to pay off.
Thankfully the rain held off for us, though it was cold.. very cold! Suggestions were made that we should rename our little group as "Brass Monkey Flight".
The object of todays exercise was to finish up the work started on No 4 engine just before Christmas. The oiling system was checked and tested again to make sure it wasn't just a fluke. Sure enough it works! While we had the cowlings off we checked and filled the hydraulic tank, before refitting everything and tightening it all up. We have a small amount of lock wiring to do but No 4 engine is more or less ready to run.
Next week will see the same work done on No 3, with the intent being to have one side prepared for running. Its been a long job so far, but we have resolved to put all effort possible into things as this year is WR963's 20th in preservation.
Rich, after a period of remaining dormant, before you start the engines on WR963 are there any preparations that need to be done to them first or is it a case of 'turn the key and cross yer fingers'?
WANTED - Westland Wyvern & Short Sturgeon parts & photos!
I'll have to ask the engineers further on this one to be sure. The engines have been getting a lot of attention.
Pre-oiling was always the problem - the new set-up and electric pumps now take care of that now though. The engines have been regularly pulled through by hand several revolutions while they have been dormant to try and avoid anything sticking. The plugs have all been cleaned, and the oil is new.
One of the last jobs is to test the priming pumps. We had a little scare at the back end of last year when we found water in the fuel, but that has been drained all the way up to the manifold at the back of the engine.
Other than that I think it's a case of plugging in the ground power and seeing if she will wake up.. No 4 was turned on the starter this afternoon and spun over nicely with no nasty noises, and no leaks. No fire cover and a lack of trained crew meant we couldn't go any further, unfortunately.
Ok thanks Rich. Just wondered if you ever had problems with cylinders firing through damp plugs etc. My knowledge is only based on car engines!
WANTED - Westland Wyvern & Short Sturgeon parts & photos!
Have you replaced the damaged cams yet?
nope, cams havent been changed
We have a few bagged fuel priming pumps for the Shack which may be available.
No point in doing any running on old cams - once the chrome is through, and the cams are damaged, they will continue to wear regardless of how much oil they are getting. Short step to a big fire then.....
I can't make any claim to be an engineer - as I'm not - but what I was told when I last asked whether we were going ahead with swapping them out, was that several of them while worn were within limits, and the worst one was going to an overhaulers for regrinding.
What the current situation is regarding them I'll have to ask about; but I don't like the idea of fire at all.
From the last report on the situation from our engine men:
"adjustments revealed little of no wear on Nr 1 and Nr 4 and some cams of these did not even require adjustment. But Nr 3 is in poor shape with extensive wear and corrosion. It is intended to dress-out the wear and re-polish where the corrosion has pitted and scored the cam lobes. This is obviously not a permanent fix , but advice from several sources is that with improved oil priming, more careful running regime at correct operating temperature and above all some fresh oil in the tanks, our very limited annual running time may allow us to continue running even Nr 3 for a year or two. Ultimately we could consider either a double camshaft change or even an engine change as a fix."
I'll let you all know as soon as I can if this is still the case.
Would appear to be self defeating to run the engine with a source of self dosing particulate grinding media contaminating that expensive new oil? Especially when you have new cams in the spares stores.
I remember the photo, it was taken of No 3 when me and Ben were stripping the cam covers off.
I don't know how many good cams we have... I think there is a reluctance to split up the last few good inhibited engines in store, as they would likely be the only source of them.
As I say, I'll have to try and clarify better what is going to happen. You guys want to know - I want to know - so bear with me, I will find out.
I think Bruce may have meant the chrome plating on the pads of the 'fingers' that follow on the lobe of the cam. As I understand it when the chrome goes beyond pitting and starts to come off, they start acting like a cutting tool on the lobe of the cam, accelerating the wear.
Any Griffon experts that can confirm this for me?
Yes, sorry, thats what I meant, but it was late!
Once the cam starts to go, it continues on the downward spiral very fast. You need to chaneg the whole CRM with a fresh one, having checked the pads on the fingers very carefully,and indeed the cam itself. Once the cam is damaged, thats it - you cant grind metal that isnt there!
All you will do if you leave it is fill the oil system with lots of metal particles, which wont do the rest of the system any favours at all.
Without trying to condone running with worn cams, are you sure there is a fire risk?
I am aware of a problem with the Merlin on bomber operations where expansion caused the valve clearances to close up and presumably torching of the flame traps.
What would be the mechanism that causes a fire with large valve clearances?
We do regrind our cams on ground-runners if we catch them in time, the hardening is 0.040" deep, but sometimes they have worn more than this and even with good filtration it still damages the scavenge pumps and in the case of the Merlin, the pressure pump as the (aftermarket) filter is located after it. The Shack has a filter that looks more than just the usual strainer on the return to tank, but I don`t know how many microns it is.
:diablo: If I had a quid for every time someone mentioned "buried crated Merlins", I could buy one!
You are of course, far more knowledgeable than I - I suspect that is what I was remembering from the various books of my youth. The Griffon 58 is of course rather different to the earlier Merlins.
So, perhaps that is an exaggeration!!
The pictures that were shown at the time showed a cam with a good chunk of the lobe missing - tenths rather than hundredths I would guess. I dont think that will last long, especially if the fingers have not been attended to.
I just dont see the point in doing all the work they are doing, and then not changing the cams. Looks like a ha'porth of tar to me!
Hope Rich doesnt mind me posting this.. Correct me if any of it is wrong mate
As far as im aware Bruce. The reasons for not changing the cams were as follows
a) As Ric said above, all the chaps were loathe to cannibalise any of the few inhibited engines they have left up at the storage barn
b) AFAIK None of the chaps up there had done a complete cam change before
c) It would certainly be a job that took longer than an the few hours a week the chaps get up at the old girl, which leads to....
d) Lack of any decent (heated?!) workspace to do what id guess is a frustratingly fiddly job
I believe that 790 in the states went through sets of cams like you wouldnt believe... Due to preoiling (lack of) and long periods of inactivity
963 has clocked 20 minutes of running (on 3 engines) in 12 months (one fireup) - I believe after having spoken to the chaps where the oil priming systems came from, it was generally agreed that with the EXTREMELY limited running of the engines, the new preoiling systems along with the new grade of oil and complete flush of all oil systems from all four tanks - that further damage would be minimal and acceptable until further arrangements could be made...
heres what we do on ours for instant starts and clean plugs!
do youself a favour to save labouring the starters, props and spinners. since you haven't run her for a long time. Do your prep in the morning and run her pm. check your lp filter bowls first, they will have water in them after this length of time.
1) in the morning, crack all of the bank fuel priming lines at the firewall and run the priming pumps, bleed the lines through to there, reconnect. 2) open all four lp cocks in the morning, push all 4 throttles fully open, and leave it that way for about an hour, then run the boost pumps briefly whilst mags off turn each engine through 3-4 revolutions until fuel issues from the bottom cowling drain.
if you do this, she will start within 1 blade turn on every engine in the afternoon. it saves a shed load of wear and stress on the starters, airframe, props, translation unit, fuses etc. that's the secret to griffon starting on the Shack, if they run infrequently, more importantly is stops you fowling the plugs during start, and saves you having to clean them that often. once shes running clean, run em all up to 26-2700 in pairs before shut down and your plugs will be as clean as a whistle on shut down
as for your cam issues, suck it and see. if that engine runs like a dog still, then you know your going to have to do a cam swap.
Last edited by mjr; 9th January 2011 at 18:50.
I believe the eng was pretty sure that the majority of the 'orrible running on number 3 was down to 2 of the cylinders on the port bang having no working plugs...
Rich better be paying attention to all the above :diablo: that said, the likelyhood of "some" listening is....
Last edited by Nashio966; 9th January 2011 at 19:15.
Ah well, you can lead a horse and all that.
None of the above is a reason for not changing them. My own opinion, and it is only that, is that if you want to play the game, then you stick to the rules. The wear shown in the picture we saw leads me to believe you are storing up problems for the future.
Don't rush it - there's no hurry!
Im nothing to do with them anymore chap
Just remembering discussions from the past... It was never a discussion I agreed with and I believe you will find that richard is the same
these are for reference - three separate lobes AFAIK
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