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Post by lumpy on Aug 20, 2008 23:09:29 GMT 12
Sounding like "sticky motor " , might actually be " mildly seized motor " . For what its worth ( in what I do anyway ) I found PB blaster to be average . I need cans with lots of pressure , and find innox to be really good . Good luck though , as you say "she is only an engine " , and your results so far speak for themselves .
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Post by Radialicious on Aug 21, 2008 21:12:42 GMT 12
Lumpy, you are bang on! She sulked for a few days in a completely seized up coma. She is mobile but as you say is still mildly seized. I have high hopes for her but am trying to get oil in amongst her bits without taking off cylinders. I'll look up Innox. My oil rig worked well today but I think I need to do more. I'm planning to make up an adaptor that I can attach to the induction 'belts' that feed the three inlet ports. If I can force penetrating oil into the inlets, much of the sleeve will benefit from that. Today, I did consider completely filling the entire engine with oil so that I didn't have to rely on internal jets that may or may not reach the dry bits! We'll see. As mental as it sounds it could be an easy fix. However, tomorrow I'll try and plumb my rig into the external oil circuit and see if that helps.
Seizy STBD is in some ways like George W's Pentagon. Slightly round-ish and all the secrets are on the inside.
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Post by Dave Homewood on Aug 21, 2008 21:37:38 GMT 12
My oil rig worked well today but I think I need to do more. It's probably a good thing you own an 'oil rig' by the sounds of things, is it in the Tasman or the North Sea? ;D
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Post by Radialicious on Aug 22, 2008 21:47:21 GMT 12
! Lack of oil was the initial problem but to look at her you wouldn't think so at the moment. I have a bottle of Jif and a Scotchbrite pad in the shower to help clean me up after a day of Bristol-ing. My tinkering clothes are looking decidedly secondhand (again). I plumbed my Husky-pumper into the external oil circuit today as was a bit surprised by the results. The circuit that lubricates the sleeve drive cranks is very reluctant to accept any great flow of oil. In fact my Husky-pumper stalled shortly after I plumbed her in and got her cranking. The outlet pressure gauge pegged itself against her stop at well over 150psi. That led to another visit to Enzed hose doctors to buy a tee, some hose tails and a ball valve tap. This lets me bypass a lot of the flow back to the rig tank and reduce and control the outlet pressure. On the first pump run I noticed a small drop in the oil level in the tank initially and then it failed to drop much further. To monitor the rate, I drew a line on the tank against the level before I started the engine. The level dropped about 1cm and then stayed put even with a good deal of pressure against it. After what seemed to be a lot of nothing, I shut the rig down and again marked the level. When I started the rig the next time, the level dropped a similar amount and stopped. After the forth run, the same thing happened. I thought at the time that the gallery might have a blockage in it. The gallery is fed from the external circuit via a 'Purolater' filter and lubricates the bushes that support the sleeve crank drive gears. As it is filtered oil, a blockage is unlikely. My rig is kept clean by filtering the return oil through one of my socks (?!?!) The sleeve drive crankshafts to the front and rear banks are hollow and port oil to the ball joints at the base of each crank. As I write this, I suspect that there isn't meant to be a huge amount of flow and the consistent 1 cm drop in the rig tank is the result of the gallery and 14 cranks filling up with oil.
I'm slowly isolating what is causing this problem. The next plan of attack is to work from the upper cylinders downwards and get into the sleeves via the three induction ports. Im confident that most of the lower cylinders and sleeves are satisfactorily lubed up just because of where they are.
She is only an engine. Man made her. Man can fix her.
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Post by Bruce on Aug 22, 2008 22:49:55 GMT 12
Have you tried the same trick on the other engine to see whether the pressures / level with the rig are similar? it might help determine whether there is indeed a gallery blockage somewhere. If I remember the sleeve train arrangement on the centaurus, the feeds aren't particularly big. Regarding your idea of filling up the engine with oil, When I was at Aeromotive I once was tasked with filling up the RR Griffon off the former Alpine Spitfire Mk 14 (The one Tim Wallis had his accident in) in order to preserve it whilst the wreck was awaiting sale. It took two of us two days to fill the sucker up - over 200 Litres of inhibiting oil! Every drop was poured through the centre of the camshaft bevel gears - about 10mm diameter - as that was the only opening high enough to get oil into everywhere. The additional weight was quite a concern as everything was loading up the attachment lugs (which were already damaged). We left it to sit a couple of days and drained most of it back out again as we couldnt move the thing that full of oil. I would hate to think how much additional weight you would be putting on the mount frames of the bristol if you tried it - I would keep that method as last resort (you would also need a LOT of oil!) I would try pulling cylinders before getting to that stage... Keep at it Al - it will come right!
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Post by lumpy on Aug 22, 2008 23:39:50 GMT 12
Have you ever tried to undo a bolt , only to have it come out a few turns then stop ? Usually you can turn them back in about a quarter turn , then back out a quarter , but nothing you can lube them with allows them to come right out without breaking , or wrecking the threads . I think this is like your engine , and fear that you may need to find the source of the seizing ,before worrying so much about lubing it . It may only be one sleeve , but if its a bad seize it may keep on "eating itself " .If its a minor sieze , it may " heal itself " . Pretty tough call really . But dont give up !
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Post by Radialicious on Aug 23, 2008 19:45:00 GMT 12
Thanks guys, that is excellent advice. Plumbing into the other engines external circuit is a very good idea. BTW, I am staggered that a Griffon would swallow 200 litres of oil! Just that on its own is a good reason to try other things. As for the engine bearers, I suspect they could handle the weight as they would have to support a whole lot more in +ve G flight conditions. Today I got Wayne Tantrum's new boroscope on the case and pumped in a good amount of engine oil that was thinned down with JetA1. This time I tied a lanyard around it to prevent the disaster with the last one! Access throught the inlet ports is probably out of the question due to a complete lack of access. However, I reckon todays work should give some results. In one cylinder, the oil which was pumped into one exhaust pipe eventually found its way out of the exhaust that is fed from the other port. This showed that it had penetrated around the sleeve as the ports are several inches apart. That was good to see. I left these cylinders soaking tonight and if the weather plays the game tomorrow I will see if it did any good and attack the others.
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Post by Radialicious on Aug 25, 2008 21:46:25 GMT 12
Had a bit of a win today when I managed to turn Miss Stbd on her starter motor for the first time in over two months. It was nice to see her turning but it felt a bit odd that for the first time, I had no 'feel' through the propeller blades. That happened just in time for yet another heavy southerly downpour to ruin my plans. I'd just set up the Husky-pump and reconnected the oil system - external and internal when the rain came. It was a bit of a bugger that it came when it did as I was looking forward to see what an oil prime and cranking would do. As I type this, it is still pissing down outside. Hopefully it passes overnight and I can launch into her tomorrow........
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Post by Dave Homewood on Aug 25, 2008 22:30:23 GMT 12
Good luck Al, it sounds like progress is being made!
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Post by Radialicious on Aug 28, 2008 23:21:22 GMT 12
Yeah Dave, progress is being made. When the weather cleared here yesterday, I set up camp again on my step ladder. After the last few days of continual downpour it was nice to see some blue sky. The first thing I did however was to buy some new workboots. The ones that SAFE Air bought for me in 2001 had served me well! I nearly threw them out today but its like a guy with old jocks or old socks - we need to be pushed. I wore those boots in the deserts of Israel on the Skyhawk project so they mean a lot to me. In Israel they would be sweet as, but in the trenches under a Bristol Bombsite, they had lost their charm. I stormed onto the airfield in my new boots this morning ready to bust some caps and get amongst it. After a few hours on the job I gained a valuable practical appreciation of the B170 oil system. With an oil pressure of up to about 140 psi, there is very little flow through the system when the engine is stationary. When the level in the tank is studied, it is clear that there is a small flow rate. If the delivery pressure is watched closely and the prop slowly turned, a noticeable drop in pressure and rise in flow occurs. This is due to an interrupted flow to the supercharger bearings that occurs only when certain ports and galleries align. Above 140 psi, the flow rate suddenly skyrockets and for a long time, I couldn't explain why. I have the scavenge system blanked off at the moment. The scavenge system incorporates what I call a 'skive' valve. When it all gets too much, the oil skives off thru the skive valve and into the oil tank via the coolers. In the context of what I am doing I don't want any oil skiving off to the tank when there are hard yards to be done in Bristolville. Also the electric isolation ball valve is closed at the moment. To digress a bit, the oil pump has the main system pressure regulator valve built into its delivery housing. If the delivery pressure exceeds a certain amount, it bypasses output flow back to the inlet side of the pump. When the engine isn't turning very fast, this only ends up in sending oil back into the tank. The B170 has emergency isolation valves that I have selected closed to prevent this from happening. Both the scavenge system and the inlet hose are an easy way for my efforts to be diverted from the problem areas. The skyrocketting flow puzzled me until I explained the results of my day to the guys from Marlborough Helicopters. I had borrowed their battery cart to run the starter motor throughout the afternoon. As I explained what had happened, it became clear that the sudden flow at high psi's was the normal operation of the crankshaft oil jets. I now have a couple of options available to me and they need careful consideration by both myself and all who care to provide some input. First up, I can crank the engine when this pressure and flow is achieved externally, and hope that the internal flayings and commotion will achieve complete lubrication. This may suffer in that the speed of the engine under its starter motor might not be enough to splash lube everything. The other option is to oil prime the engine as best as I can and start her knowing that splash and pressure lubrication is guaranteed by the fact that the machine is running. The bit that I have to get my head around, is that the engine isn't as free as I want it to be. Will it free up after a short run or will I be back at square one? I do know (from experience) that she ran beautifully on little or no oil pressure for her glorious minute. A tentative plan is to crank her over a couple times when it is clear that the crankshaft jets are at their oil gushingly best and then attempt a 30 second run.
She now wants to go again and I know the port engine is fizzing at the bung (not in the techical/chemical sense) to have another run. There are blossoms on the trees in Bristolville at the moment. Hopefully they can pass on some of their enthusiasm to old CPT. Its hard to believe that a whole season has passed as I battle this problem! Perhaps the change is season is symbolic. Today I finished off my part in the annual servicing of our beloved Andrews Special ZK-BLU. I did find some time however to have a quick swing on a prop blade and the result was heartening. Hopefully a full day in Bristolville tomorrow will provide some good results.
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Post by Radialicious on Aug 30, 2008 19:58:35 GMT 12
JOB DONE!!!!
After two months and two weeks of battling against a very sad and stubborn 2360 cubic inch monster I finally got the result I was after. I'm not sure what was more rewarding - bringing those two big engines back to life or reversing what happened to the STBD one.
It had become clear that the only way I was ever going to get her fully lubricated was to either pull her half to bits or, (after very careful consideration) attempt to start her up. My fear was that if I was unsuccessful, I could be back at square one - or worse....
Today three of us put her all back together again to see if the starter could cope with the stiffness and 14 sets of compressions. I was surprised to see that she could. Suddenly I had the decision to make with regard to firing her up again. It was pretty clear that I should give it a crack. All the right signals were there and deep down I knew that if she ran so well last time without lubrication, there was a very good chance of a good result WITH lubrication! I had the husky-pump running and pumping out a nice 100 psi in the cockpit before I flicked the switch. That wee machine is worth its weight in gold!
The end result was an engine that roared into life and ran beautifully with a nice steady 120 psi on the gauge. She started on the first attempt and coated everything behind her with two months and two weeks of almost every type of oil know to man. After a couple of minutes of running I shut her down know that the biggest test was yet to come. Would she remain nice and free? I felt a huge relief when my mate on the ground was able to move the prop with one hand. That was a great feeling! After a quick inspection of the engine it was round two. Again she roared into life and with Roger in charge, I left my seat to stand in the cockpit escape hatch to survey the commotion. All I can say is awesome! It is an incredible sound even at idle. Down below was the lucky audience that just happened to be around when she woke up. Lots of grinning faces.
I look forward to tomorrow afternoon when I get to run both at once for the first time. Watch this space!!!
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Post by Bruce on Aug 30, 2008 20:17:01 GMT 12
Good stuff! well done that man. Important note - photos and or video of dual engine run are mandatory!
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Post by Dave Homewood on Aug 30, 2008 23:37:01 GMT 12
Excellent work Al, well done to you and your helpers. Good luck for the double run tomorrow.
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Post by Radialicious on Aug 31, 2008 21:50:27 GMT 12
As the above photo shows, it seems like the hard stuff is now done and dusted. We managed quite a good audience this afternoon and again there were many smiling faces. One of the biggest smiles I saw was that of my 'First Officer' Jim Howard. Jim was the delivery pilot of ZK-CPT from the UK. His daughter is my landlord and I arranged for him to share the cockpit on the big day. Jim is quite elderly now but shocked his family by scampering up into the cabin and cockpit without the assistance of his grandchildren who had turned up to help him. Good old CPT didn't miss a beat today and ran perfectly. She is still a bit rich at idle but settles down nicely above 1300 rpm. I was quite wary of the fact that I now had double the thrust tugging at the tiedown chains and chocks but was able to run each engine up in turn to 1500 rpm. A lot of comment was made regarding the vibration that comes out of the ground when you stand nearby. My former CO and SAFE Air boss Mike Nicholls said that she is only half the sound of a Halifax bomber and wondered what a 300 bomber raid must have sounded like. Certainly not steathy........ I look forward to checking it out for myself. In the meantime I'm enjoying the beautiful din in the cockpit. Jim said it played havoc with his hearing aids! I imagine it is the same as blowing a referees whistle down the ear of a German Shepherd. He didn't sound like he was complaining tho. My good mate Wayne Tantrum shared the cockpit also. It was good to give something back to him after he has helped out so much with equipment and materials. He also enjoyed the view from the cockpit escape hatch. Ryan Southam turned up just in time in a Tiger Moth to get a Bristol fix on his stop over. There are now just a few small jobs to do before I look to reactivate the pneumatic system to complete her return to taxiable condition. Now that she is a known quantity again, I look forward to sharing her with the public. Friends of the Bristol plan on public running events every two months until Easter. There are a few of us that are also keen for a night run that should show off the effect of 28 short straight exhausts. The cowls for a good metre or so behind the exhausts are steel so I imagine the flames should be quite impressive. There is a certain rpm that the Hercules have a very distinctive note that is quite unexpected from a twin row radial. It is almost a brrrrp, brrrrp, brrrrp type sound that that almost sounds comical when they are both doing it together. I will try and quantify the cost of a ground run so that they might happen on demand from interested groups. The AHC has the odd tourbus load go through the museum and if enough interest is shown by those visitors, they can have a fully 'interactive' visit to Omaka. There was a bit of video camera action around today so hopefully I can hook up a bit YouTube action. Those of us that were beavering around her today had a good old time. Suddenly the big old girl was relaxed and ready and looking forward to getting rowdy just as much as we were. It was interesting to note that the Husky-pump starter cord broke just as the rig was started for the last time priming the port engine. She had worked incredibly hard over the last few weeks of repairing Seizy STBD and held it together right to the very end. The other outcome of choosing 5pm to flick the switch was that the aeroclub bar was open. A number of pints were chopped whilst watching and hearing a living machine that for the last twenty years had been a silent relic that possibly hadn't even been noticed by many visitors to the clubrooms. It was kinda cool to leave her tonight in the dark with warmth in her cowls and suspect that she enjoyed her big day almost as much as we did.
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Post by nzompilot on Aug 31, 2008 22:05:43 GMT 12
Nice work Al, but did you have to do it when I had rehearsal and couldn't be there to see it?? So when is she going for her first taxi under her own power?
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Post by flyjoe180 on Aug 31, 2008 22:16:06 GMT 12
Great work Al, and a fabulous photo from Gavin too.
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Post by Peter Lewis on Aug 31, 2008 22:31:32 GMT 12
Well done that man. Looking forward to next Easter. My own hearing has never quite recovered from an Air Scout trip Whenuapai-Ohakea in a RNZAF B.170 40 years ago. I can hear the din still.
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Post by Radialicious on Aug 31, 2008 22:37:19 GMT 12
Aha, Craig! Good point. However you are in an enviable position to be only a few minutes away from any Bristol Blowout in the future.
We tried pretty hard to refit the port spinner today to get the aesthetics just right but for some reason she wasn't very keen. The diaphragm that supports the spinner against the prop dome is lined with Bakelite and I suspect its internal diameter has swelled somewhat since being removed.
I'd dearly like to sort out the pneumatics and brakes so that she could taxi off her pad and onto the airfield under her own power. I think that would be quite symbolic and triumphant. However, the chance of something going wrong - ie taxiing into the clubrooms or demolishing a fence or two is up there. There is about 4 ft of prop clearance so taxiing across gravel is probably not too serious. We'll see. As I type that, I fall back on my Bristol Mantra - she doesn't belong to me and any doubts about anything should be met with "is there a better way?"
I intend to charge the pneumatic system with a dive tank shortly just to see if it is still intact and functional. I know that both Hymatic compressors aren't charging and as I understand them, they are quite simple.
To see her taxiing will be quite special!
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Post by baz62 on Sept 1, 2008 16:42:26 GMT 12
Well done. I love seeing and hearing radial engines running and would love my own engine project one day. I was lucky enough to be one of the few allowed to ground run the RNZAF Museum's Avenger in 1980 (I was only 18 and one of the Sunday volunteers so was feeling very privileged!!) I also remember one of my jobs on the Museums freighter removing all the plugs and spraying inhibiting oil into the bores and praying I didn't cross thread those long long plugs putting them back in! (I must have done a good job as those original engines ended up on the Safe Air Bristol donated to the Museum and then flown to Canada! Wish I was closer I'd lend a hand so will have to see about being there when you fire her up sometime (with various recording devices about my person!!!!) Here is NZ 2504 being runup by your's truly circa 1980: rides.webshots.com/photo/1531332790083531880HuCFmo?vhost=rides
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Post by Dave Homewood on Sept 1, 2008 17:11:44 GMT 12
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