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[SailorGreg]

A question for those who have been here before me -
A couple of evenings ago I was running the engine to run-in the water pump (and for the joy of watching all those different parts moving in harmony!).  I stopped the engine to wipe off some dirty oil, then it wouldn't start again.  Even turning by hand it seemed rather stiff.  Puzzled?  Just a bit.  Anyway, when I persuaded it to turn by hand, I noticed (eventually) that the valves were now moving in time with each other - that is, they both reached the top of the stroke at the same time.  Obviously one of the eccentrics had slipped.  I know when I built the engine that I was probably cautious tightening the tiny set screws that hold the eccentrics in place, so slipping isn't too big a surprise.  I re-timed the engine and now it runs better than ever, and I did the set screws up as tight as I dared - in fact as tight as I could using the miniature allen key provided.

My question is, is there a chance of this happening again, and is there anything I can do to prevent it?  Obviously the timing going out in the middle of the lake is going to be a bit of an issue.  Has anyone had this problem when running, and how did you fix it?

Greg

[Jerry C]

Mine has had no problems. I followed the instructions. Used no loctite. The secret of the little Allen key is that it IS little. When tightening it bends alarmingly but doesn't break. I bent mine about 90 degrees when tightening the grub screws and (fingers crossed), no slippage. I agree it's not a good idea if it happens on the lake.
Jerry.

[pettyofficernick]

Hi Greg, I had the same problem, it happened twice, I eventually put a tiny drop of threadlock on the allen screw with a pin, and all is good now. A couple of bolts on the valve linkages also worked loose during running in, these I also cured with some threadlock, again, applied with a pin. I used the low strength variety of locking compound to ensure the job can be taken apart without too much fuss should the need arise.

[SailorGreg]

Thanks guys - I have snugged up the set screws as much as I can and I'll leave it at that for now.  It'll be a while before the steam plant goes beyond arm's reach, so there's plenty of time for it to go wrong again if it is going to happen.  If it happens again I'll break out the Loctite. 

Greg

[SailorGreg]

OK, a little riddle for everyone - when is 1/8" not 1/8"? 

Answer- when I try to put my 1/8" tube into an 1/8" nipple. It doesn't fit.  It's not a big difference but enough to make it impossible to join the two.  Do I just use some emery cloth to reduce  the tube diameter a bit, or pop the tube in the freezer for half an hour?  Obviously a bigger hammer is not the answer in this case but it does seem odd to me that what should be a sliding fit isn't.   

Is this a common problem?  I have had no problems with the 5/32 nipples.  If I buy another batch of nipples from a different supplier will that solve the problem? 

Greg

[pettyofficernick]

Never had a problem like that before, I would try some from another supplier. Are you sure you are not trying to fit metric pir into imperial nipple or vice versa. A possible problem trying to shrink the pipe is that you could end up with insufficient clearance for the solder to run. Hope this helps,
Regards,
Nick.

[SailorGreg]

Well, I ordered 1/8" for both the tube and the nipples - admittedly from different suppliers.  The label on the tube says 1/8" as did the label on the bag the nipples came in.  I'll order some more and see if that makes a difference.

Meanwhile - the connections are all made apart from the water feed from the pump.  Sometime soon I'll run out of excuses not to fill the boiler and light the burner    More news  and piccies soon

Greg

[pettyofficernick]

Gerrit lit man! I get all my pipe and fittings from steamfittings.co.uk, good quality, good prices and usually arrive next day.

[SailorGreg]

Well, a bit of a red letter day today.  I filled the gas tank, filled the lubricator, checked all the connections, filled the boiler, lit the gas - and it all worked!!! 



So I am pretty happy so far, but I now have a whole raft of questions.  Most of these are novice stuff I am sure, so apologies for that.
Firstly, filling the gas tank.  I assume you should fill it until you can feel the gas sloshing around and it is mostly full by feel?  I found I was nearly out of gas, so I couldn't fill the tank more than about a quarter full, if that.  When I get a new supply I'll have another play with this.  And I assume that leaving gas in the tank is not a problem?
Next filling the boiler.  I was using a large syringe to fill the boiler and I expected the sight glass to show the level in the boiler - but the water overflowed when the sight glass was only this full -



I did try tilting the boiler, and the level rose in the sight glass, but I didn't seem to be able to get any more water into the boiler - it just overflowed.  What am I missing?  I put something like 300 ml into the boiler.  The spec on the Maccsteam sight says the capacity is about 750 ml so why did I keep getting the overflow?  Was I just filling it too fast?  Or is there a special technique like putting a narrow flexible tube into the bottom of the boiler and filling through that?

Anyway, the pressure built up pretty quickly, and after about 7 minutes I opened the steam valve.  There was quite a lot of water bubbling out of various places on the engine, but once I gave it a flick it ran fine.  It kept going for about 8 minutes, then the pressure started to drop and after a few stop-starts, I decided that was all I was going to get from my first run.  The level in the sight glass had dropped almost to the bottom of the glass by this point.  The gas tank was also pretty low.

Another question - should I drain the boiler completely after each use or is a small amount of water left in there OK? 

There are a lot of small leaks around the engine so I will check the tightness of all the screws.  If that doesn't fix it I will probably revert to the gaskets supplied with the kit.  And in case anyone is wondering what that closed-off stub of pipe is by the sight glass, I have a gas attenuator on order from Forest Classics and that will be the line that supplies the boiler pressure to the attenuator.

So, not a bad day.  I have more questions than answers at the moment, but that's half the fun.      I need to get some more gas then I'll do a few more runs to learn some more about how to make it all work properly.  In the meantime, any advice for beginners most welcome!

More news soon I hope.

Greg

[Kerrsy]

Hi Greg
I don't wish to teach you to suck eggs but did you order 1/8th i.d. or o.d. that could be the difference.
alan 

[pettyofficernick]

Hi Greg, are you sealing the filler/safety valve hole with the syringe when filling, this would not allow the displaced air from escaping. I use a laboratory wash bottle to fill mine, it is basically a flexible plastic bottle with a curved plastic tube about 1/4" od which fits in the hole nicely and allows air to escape. Fill your gas tank as you would a cigarette lighter, ie untill a little gas escapes from the filler valve. I presume you will be doing this with the tank out of the boat, as the gas is heavier than air and any overspill will lie in the bottom of the boat. I usually leave the boiler as is after a run and top up at start of next session, although others may disagree on that one.
Regards,
Nick.

[SailorGreg]

Hi Alan, yes I believe I ordered the right tube and nipples.  The tube is definitely 1/8" od - it says so on the label and on the vernier when I measure it - and the nipples are VERY NEARLY 1/8" id - but are about 0.03mm shy of being the right size (sorry for the mixed units!).  I've ordered some more tube and nipples, both from the same supplier, and we'll see if that sorts it.  And please don't worry about the egg sucking - I really am a neophyte when it comes to anything engineering or steam, so I welcome being told the simple things.  Anyone familiar with a subject tends to assume that everyone knows the basics - they're obvious aren't they  .....  No, not to me!!

Hi Nick, you might be right, my syringe does nearly fill the hole, maybe I'm simply trying to force the water in without letting the air out.  Next time I'll do it much more gently.  As for the gas tank, yes I'm filling it out of the boat - mainly because I don't actually have a boat yet!  I have just got back from buying some more gas and filled the tank as you suggest.  I've also been round all the screws and given them a tweak to try and close the leaks.  Tomorrow we'll have another go 

Greg

[SailorGreg]

Well that didn't go quite as well as I'd hoped.  I filled the boiler more slowly with a smaller syringe and that worked well, albeit a bit slow!  Lit the burner, and I had 30 psi in 10 minutes.  I opened the valve and got some hot water bubbling out of various places around the engine, but when I flicked the flywheel the engine ran fine.  The pressure dropped to about 10 psi straight away, but the engine seemed to be running OK.  I had less steam escaping around the engine so tightening the screws obviously did some good.

After about 5 minutes running, the engine slowed and stopped.  I span the flywheel and it started again, but a bit reluctantly.  It did this a few times then wouldn't start at all.  Pressure still 10-15 psi.  I couldn't persuade the engine to turn by hand so decided to abandon the run and see if I could figure out what is going on.  Even with all the pressure released, the engine still seems locked up (although it hasn't cooled down yet). 

None of my pipes are insulated yet, and I know you can get hydraulic lock from steam condensing in the cylinders, but I thought once the engine was running and warmed through that this wouldn't happen.  Why might the engine lock up after 5 minutes running?   Given that the engine ran on air for as long as I cared to leave it switched on,  it is clearly something to do with running on steam - but what?  As it stands this engine isn't going to be driving anything anywhere - apart from me to distraction!

Help!  Any suggestions or solutions?

 

Greg

[pettyofficernick]

Hi Greg, check the clearances between the linkages for the valve gear, and also that they are tight, also make sure the allen screws on the weighshaft are secure and that one side or t'other hasn't slipped. That also happened to me. There was a distinct rubbing sound when I turned the engine over by hand. Recheck all the valve gear and timing while you are at it. I had to set timing 3 times as it kept slipping.
Regards,
Nick.

[Jerry C]

First observations. Boiler should reach 60 psi in 8-10 minutes and safety should lift. Keep heating and pressure should stabilise at <66 psi. This engine needs to be run slowly, throttle only just open. Experiment to find the max revs for steady pressure. This is for bench test. In the water the throttle will need to be opened more but only enough to keep the rpm low. You will need a big 3 blade prop with 4-6" pitch. The engine should be run at 35 psi according to the maker and I try to do this but it doesn't fly apart if you run at more pressure. Is there any restriction in the exhaust side and does plenty steam come out of the flue? Can you see thin oil film on top of condensate in separator. Is the feed water entering the boiler hot. Feel pipe just before the clack valve. If eyes water it's ok. If feed water cold then pressure will plummet. I have heating coil in flue. Cannot vouch for heating coil in separator. Engine will need to run for a while before separator. Gets hot enough(I think) whereas flue heater(economiser) is instant. I was advised not to fit an economiser so didn't. Big mistake. It proved vital. Hope this helps you.
Jerry.

[pettyofficernick]

I have a preheater coil in the seperator, works fine, water comes out hot enough to brew up with, I tried it, made a nice cuppa it did. Only takes a few seconds of running to get nice and hot. I have posted a video link a while ago of it working.
 http://www.youtube.com/watch?v=uXE0a38D1Iw&feature=youtu.be

[SailorGreg]

Wow, you guys must have been lying in wait to respond so quickly!

Yes Nick, I think the timing might have gone out - it just seems odd that it happened after 5 minutes of steam but not after 50 minutes of compressed air.  I'll check that, and all the other linkages and stuff.  I have decided I will fit the gaskets as well, to cut down the leakage as much as possible.

Jerry, thanks for the advice.  I will let the pressure build up rather more next time before letting the engine run.  Yes, I am getting plenty of steam out of the exhaust and yes, it does have a film of oil on it.  I'm not actually using the oil separator at the moment, just an old butter carton so I can see exactly what I am getting out.  I am also not filling the boiler when running either.  The pump is fitted but not connected up yet, so cold water isn't affecting anything.  The suggestion to "pre-warm" the water is a good one, so I will think about running the feed through the flue when I do get around to organising the top-up water.  Right now I just want my engine to run for 15 minutes without needing attention!

A bit of work to do on the engine, plus I apparently have some chores ( ) so it will be a day or two before steam is raised again.

Thanks again for the help.

Greg

[pettyofficernick]

Hi Greg, remember everything will expand slightly and tighten upp a bit when running on steam, as I said, mine ran like a clock on compressed air, but it took 3 go's to get it running right on the hot fog. Keep at it and you will get there.

[SailorGreg]

Not too sure I am progressing much at the moment.  After my last attempt reported above, I rechecked the timing.  It had gone off a bit due to one of the set screws in the reverse linkage connector slipping, so I tightened that up, reset the timing, ran the engine on compressed air - everything hunky dory - then lit the boiler again.  I intended to follow Jerry's advice and let the pressure get towards 60 psi before setting things going, but the safety lifted at just over 30psi.  OK, not to worry, open the steam valve and run on that.  Well, no - the engine barely turned over and then stopped.  It was rigid - couldn't budge it by hand.  I let it all cool down and rechecked everything.  The timing seems fine and the engine runs beautifully on air.  Tried again this morning - raised steam to 30 psi, opened the steam valve, the engine ran for about a minute then started to sound laboured and I could hear something rubbing badly.  It stopped after a minute and a half and again I could barely turn it by hand.  One good thing - the gaskets seem to have fixed just about all the annoying little leaks.

I am not discouraged, just puzzled.     I clearly need to do something different, but I'm not sure what.  If the timing is right then what stops the engine running when I put steam through it?  All the linkages and locking nuts seem firm, nothing binds when the engine is turned by hand or run on air.  What should I try next?  Nick, did you make any adjustments to get the engine to steam properly?

Tried to phone Mike at Maccsteam this morning to ask about the safety but he is obviously busy building boilers.  Not sure if he knew I was going to be using the boiler with a TVR1A but if he did he might have set the safety at 30psi on purpose.  I'll drop him an e-mail. (Is the safety valve setting something you can play with yourself?  If so, how do you adjust it?)

Oh, and the saga of the 1/8" nipples continues - got some new nipples and pipe with the same result - none of my nipples fit any of my pipe.  I assume they ought to slide on just like the 5/32 ones do on to the 5/32 pipe?

I hope to get to my local club on Thursday (intended to go last week but a sick cat put paid to that) so with a bit of luck I might meet someone who can point me in the right direction.

Gosh this is fun, isn't it!   

Greg

[Jerry C]

Sounds like an elimination procedure required here. First off the safety valve. When I got my Maccsteam boiler I asked Mike if ok to reduce from 60psi setting to 35psi and he said that they sometimes become unreliable when slacked off so. Not unsafe but erratic. I did it anyway and found he was correct. I reset it to 60psi. The thread is finely center popped to lock in position. Your boiler certificate states the designed working pressure (mine states 60psi). I'm assuming that's what yours is set for. Many peeps say if you change the setting you invalidate the stickyfoot. Mike says not so. Stickyfoot only for boiler itself not fittings.
Also not good practice to use fitted gauge to reset safety valve. So I would deco have a chat with mike to find out if he set it at 30psi or 60psi. Once that is sorted I would confirm that the oiler really is working. Fill it to the top and then screw down the top. This will force some oil into the steam supply pipe. At the end of a decent run, check the oiler drain. Does a drop or two of water come out. If so good as this is the water that dispolaced oil into engine. If no water then oiler not working. I would try it with needle valve one turn open and reduce later as you gain experience. Next I would disconnect the exhaust pipe at the manifold and exhaust straight to atmosphere in case of build up of back pressure in exhaust/separator/flue. (You never know). How long did you run in on air before changing to steam? What grade is your steam oil? Mine is 600sae. Like syrup when cold. Ok when hot. Any more and I'm stumped I'm afraid. If all your grub screws are tight why should a thing slip? When it tightens up can you jiggle the big ends with tweezers? If yours is the BB version these are the only bearing surfaces that can pickup. The bores have o rings and so unlikely to pickup. Can't think of anything else and brain hurting. Over to you George.
Jerry.

[ooyah/2]

Guys,
Unfortunately I don't have any experience running TVR engines but there seams to be some people that  have no problems with them but others have.

In Gregs first pra it is in my opinion that a Hydraulic lock  is happening, i.e. steam condensing in a cold cylinder.

In all of the bigger engines that I have built, D10's and 10V's, it's only a matter of wiggling the forward reverse lever to clear the condensate, I no longer fit cylinder drain valves they are more trouble than worth.

If the engine was in a boat with a prop fitted it would only be a matter of turning off the steam supply and turning the prop by hand , firstly clockwise and then anticlockwise to clear the condensate and then bleed in the steam to get the engine to run with the help of turning over with the prop.

If screws are coming loose I would start from scratch by timing the engine and put a dab of 243 on the screws and let them cure overnight before trying it on steam.

Is there a steam dryer fitted to the steam line ? perhaps if not the wet steam from the boiler is only aggravating the hydraulic locking process.
Could it be unlagged steam pipes that is condensing the wet steam further before getting to the engine.

If I was fitting a steam dryer to a boiler I would not fit anything like the hair pin bend that Mike at Maccsteam supplies, in my opinion they are useless, I would make a coil which fitted tight to the inside of the funnel, 3-4 turns would be enough, this would get the heat from the burner more effectively.

Jerry I can't think of what you mean in your last para, what is the bearings and the "O" rings picking up ?

I am sorry that I can't be more helpful but the smaller the slide valve engines and steam pumps are, the more trouble is experienced.

George.

[Jerry C]

Sorry George, picking up, automotive term for partial seizure during running in. Shows as smears of one metal on t'other. Frees off on cooling.
Jerry.

[derekwarner]

Greg....you have some sound advice here from Jerry C & ooyah/2 & you could work through the points....however in parallel with this why not pen a note to the manufacturer
There may be a simple explanation or recommendation he can make........good luck.....
Just one question....those successful air trials...what air pressure are you using?.................Derek
 

[SailorGreg]

Thanks everyone for the advice and encouragement.  It's nice to know I'm not alone!      Jerry, I am sure the oiler is working - the oil is going somewhere, and I drain water out of the lubricator.  Don't know the sae (I just bought steam oil), but yes, it is like golden syrup.  I ran for about 2.5-3 hours on air and made sure everything was well oiled when I did so.  Everything certainly feels smooth and easy when you turn the cold engine over by hand.  George, I think you are right, my problem is probably hydraulic lock, because when I turn the cooled engine over by hand, spurts of water come out the exhaust.  I don't have a steam drier at the moment - just straight out the boiler and into the engine.  There seem to be plenty of TVRs running perfectly well without drying the steam.  Maybe something for the future.  However, I did put on some temporary lagging -



OK, not too pretty at the moment but better than nothing.  Derek - I haven't contacted Graham Industries at the moment - I think there are more things I want to try first to see if I can crack it.

I also had an exchange with Mike Abbott about the pressure gauge.  He had set it to 30psi, which explains that, and was perfectly happy for me to adjust it.  I did so, although I didn't really know how much to turn it.  I think I did about 1 full turn or a bit less, and as we'll see later that seemed to do the trick.

The other lesson I have learnt is about filling the gas tank. Previously I stopped filling when the liquid gas bubbled out around the filler, but I have now discovered that you need to pause, then fill again - and again.  I had about 5 or 6 goes before I could feel a reasonable amount of gas sloshing around inside the tank.  I also have been following the advice on the Mainsteam site not to hold the tank when filling it.  You want a warm canister dispensing the gas but a cold tank receiving it to get maximum pressure difference between the two.

So of I go again, fill the boiler and light the gas.  The safety lifted at about 50psi by the boiler gauge and I opened the steam valve.  The engine started, ran for about a minute then slowed and stopped.    I moved the reversing lever back and forth, spun the flywheel and the engine ran intermittently.  After a few stops and starts I discovered that if I left the lever in the "economy" position at the bottom of the detent bar (ie one slot up from the bottom), the engine ran fine.  If I tried to change direction, it stopped and only ran intermittently.  Similarly, if I moved to the very bottom slot, it ran slowly and then stopped.  Only in that one position would the engine run well.  So I left it there and had a 20 minute run.  I could adjust the speed with my throttle, from a slow tickover to - well, fast! I tried a few times to reverse the direction or use the "fully open" position, but with the same result.  The boiler pressure was about 35psi during the run.

So, success! My engine has run on steam until I stopped it, not until it stopped itself.   

But it is still a little way from being reliable in forward and reverse - and I am puzzled by it running in the economy position but not in the fully open position.       Other than some more careful checking of the timing, is there anything else I should be looking at?

As the old British Rail slogan used to say - We're getting there!!   

Greg

[pettyofficernick]

Hi Greg, have you centered the slide valve so that there is equal opening of the ports, maght be worth rechecking, keep at it, you will get there in the end.