Has anybody bushed valve guides yet??

[hotater]

 I'm going to be bushing my Listeroid 6-1 valve guides in the next month or so.  Has anyone done the math and found the reamers, bushings and correct sizers, yet?  I'm hoping it's standard enough to find something close on the shelf, but I have the bronze to do it on the lathe otherwise.

[quinnf]

Jack,

I guess so far that's a "no."  What's the objective?     Clueless individual needs to know, and all that.

Quinn

[hotater]

Quinn--

At just over 2000 hours my pinion and cam gear failed.  While repairing I did a complete teardown and measured and microscoped and examined just about everything.  I'm just trying to identify the weak links and improve on them.  This is my prime generator and I'd like for it last several years before *needing* something done.

There's a report on George's site on the failure and findings.  My guides are very worn now.  The stems are within tenths of being right, but the guides are several thou over.
    There are several grades of self lubricating alloy bushings materials made and I was hoping somebody had alread found the secret formula.     Right now it looks like a tin/bronze bushing with figure eight oiling groove covering the top 80% would be my number one pick for the Listeroid, but some of the sintered oil-lite materials would be a VERY close second...and that's available to me now.  I have some 1/2" round stock in the shop.

The GOOD news is that the guides are within shimming distance of being straight up and down in the head.  I can block the head up from the bottom on the milling machine bed and indicate true from the valve seat and ream, seat, and size the bushings in one set-up without pulling them....OR, if somebody tells me it's no hassle, I can pull the guides and just chuck them in the lathe and do the whole job there in much less time.

I'm also going to make and install a manganese/bronze bushings on both cam ends.  The end towards the fuel pump takes impact loads.

[quinnf]

Jack,

Yes, I heard from George that the gear failures were confined to one supplier.  Don't recall the name, but the gears in the Ashwameghs are marked Swastik, which wasn't the company George mentioned.  You know, the lash in the gears is pretty bad.  Every time a cam lobe passes 12:00 you can hear the gears lash back.  Don't know if that happens at speed, but if it does, that could explain the failures. 

I noticed my guides were looser than I'd like them but didn't bother to pull them.  According to the manual, the inlet guide may be pressed out, and the exhaust is threaded.  Turn CCW to remove.

Pardon my ignorance of this subject, but regarding the oiling grooves and such, won't the exhaust valve stem be too hot for oil?  I thought guides were usually ceramic these days.  Wonder what the Brits used.  Theirs seemed to last a long time . . .   

Quinn

[hotater]

Quinn---

My gears were not marked in any way....not even timing marks on them.  The engine is a Prakash FuKing and, as you can see by the photos on George's site, was pretty much as crude as it could be made and still run, but the holes and decks and location points are straight and square so the foundation is good and the details bad.  I can fix details but not foundations. 

I'm running an experimental gear from Joel now that so-far shows NO wear except tooth polishing and I don't hear the clatter of the gears as much.   I'm paying close attention to backlash all the way around the gear.  They fail by wearing away most of about nine teeth.  A new gear should have NO backlash in that particular spot....mine is consistent all the way around. That means the wear came under power, by force, instead of from a miss-fit.  Hopefully the harder gear from better material will solve the problem forever.

Valve guides have come a LONG way since lead-free fuel came along.  Bronze or cast iron used to be the standard, but with no (lubricating) lead in gas engines and the drastic increase in head temperatures in modern engines have made ceramic guides and Hastaloy valves a good choice.  They're usually sealed at the top and get no oil at all.

http://www.anchorbronze.com/    This site *really* opened my eyes to the possibilities of alloy bushings and their design.

The Listeroid is built so that the oil in the valve guide recesses under the springs serves as a reservoir for valve stem lubrication.  The exhaust valve guide has a slight 'bell' near the bottom internally that fills with carbon and acts as an oil seal.  (Clean that recess every 500 hours or so).  The intake tries to draw oil down the stem on every intake stroke.  The figure eight groove in the top of the intake bushing will spread the oil around the valve stem some and prevent 'channelizing' of the oil "flow"....actually very little oil is present there and one reason the sintered oil-lite material may be the best choice.

I was surprised at the wear of the cast iron guides in 2000 hours, but there’s cast iron and then there's *Indian* cast iron.  Mine is probably from the same outfit that supplied the pinion gear.   (I heard they lost their boat anchor contract because the porosity made them float.   )     

I talked to an old friend yesterday that's re-bushed a BUNCH of valve guides.  He suggest making new bushings from oil impregnated bronze and said doing the job on the lathe with the guides out of the head is best in this case.  Factory bronze bushings are usually very thin and have to be internally swaged to keep them in place.  That’s done during the sizing operation.  By making a thicker-walled bushing I can just press them into place then finish ream the bore for a valve stem slurp fit.  No oil grooves are needed with sintered/oil impregnated material, just a 'funnel' chamfer at the top of the guide.

"Wonder what the Brits used...? 
     ME TOO!   I'd love to have an original Lister just to look at, inventory and examine, but I've never seen one.
    As a pure gun guy with a penchant towards perfection, I've studied and worked on a LOT of English guns....even been to England to see for myself.
    The mechanical designers and craftsmen in Briton 'between the wars' were some of the best the world has ever seen.  They took a 'worst case scenario' look at everything and then designed 'prevention' into the original parts.  The quality of the materials, whether for furniture, guns or engines, was the best the world has ever known, before or since. I saw common *windows* in Scottish farm houses that would cost more to make now than the wall to put them in!   Amazing detail and over-engineering.  I love it!

Here's one of my favorite web pages to show people that say "You can't expect something to last forever.."
http://www.greenandcarter.com/

[quinnf]

Let's see.  Whois . . . yes just as I thought:.

[kpgv]

Hi Hotater,

Any luck with the valve guide job?
I think the main potential problem is tooling.
The way metric, inch, and on these "whitworth" get combined can be frustrating.
We used to "knurl" them sometimes.
It was more like a "thread former" tap, and then ream.
There were those that swore by this method, and thought it was better than new guides.
I don't know.
If the origonals are removable, are they "wet"?
I had trouble with a BB Chev that had a water leak on a new guide one time.....Major problem.
Anyway, let us know how it's going.

Thanks,

Kevin

[Reno Speedster]

I went to see my machinest today to look at the head now that its all apart and it turns out that the valves are very loose straight from the factory, loose enough so that I could rattle them in the guides.  They are going to bush them with bronze bushings and fit the valves to the bushings.  Hopefully this will improve their service life.  I am also having them chec and see if there is another valve which can be substituted for the origionals.  Modern valves are much better than the old stuff. 

[hotater]

It would be easy to 'over-technologize' one of these engines.  One reason they do well on dirty fuels and 'unusual' fuels is that tolorences are generous by design.  Tight fitting, ceramic/carbine/ect.  valves CAN be a detriment to trouble-free operation.  The *operator* is the oiling system. 

    Remember,  the Lister has built-in valve lash tolorences that self centers the valve in the seat well before ignition.   The reason to bush the guides is to prevent further wear, because once a part gets room to 'run' it'll keep wearing due to abrasion AND impact from the sloppy fit. 

I've not found anything metric on my Listeroid, but I haven't checked everything, yet.  I tend not to notice when the primary wrench is a Crescent.   

I intend to fit new bushings to the same specs John Deere and Cat and others used before turbo charging and other high performance engine designs increased  speed, friction, heat and pressure.  The purpose of oil-lite bushings is to reduce the dependance on faithful lubrication.

Right now the valves are still sloppy and the guides need bushing,  BUT, there's no oil spatter from high-pressure leakage around the valve stems or other signs of distress.

I had made plans to attend the procrastinator's convention this year....but decided to put it off again.... 

[kpgv]

Hi Hotater,
This is a thought provoking post.
I'm an avowed " Complicationelest"....
"If it ain't broke, don't fix it"
You're thought about the valve oiling system being "operator" gave me an idea...
What about putting one of those "morning" oilers like "Bridgeports" have to oil the ways to work on one of these.
When I was in College, I worked at an old style "service station" on the weekends.
There was an old guy in town that had a ???1914??? Olds that he would drive down when he needed gas or to mount a tire.
The engine was a straight "4", overhead valve, with "open" valve gear like a "Lister".
On the "dashboard" was an oil reservoir with ~12 little "finger" pumps to put oil on the valve gear while driving....
Hope all is well up there.

Kevin

[hotater]

Kevin---

A Bijou oiler would sure work but you'd have to replace the return spring that forces the oil....with the Lister clearances in the valve train it'd leak like a stepped-on frog otherwise.   

I thought about all kinds of ways of doing it including fitting an oil pump and a drain line that went back to the cam end bearing, but the truth of the matter is.....it ain't broke!
  BUT, they ain't perfect, either.

I'm toying with the idea of a gravity oil system that just drips oil in critical spots all the time the engine is running.  Mine uses a pint of oil every 30 hours or so....a quart of oil hung in the rafters with a Medusa-like cluster of three or four 1/8 copper tubes with little end valves on them.... should work, but anti-sieze and assembly lube is long lasting stuff!  An average of one 'squirt' of oil per day for the rockers is sure not excessive and three squirts every three days works just fine.

The originals had grease twist caps on the rocker shaft.  I recovered an old lube cup up in the bone yard and may put that on the next rocker shaft.  I'll bet some lo-tech moly grease forced into bronze rocker bushings on a hardened Thompson shaft would last longer than basketball play offs.   

And,   the rocker shaft and arms are standard sizes.  Sealed needle bearings would make lubrication of THAT part moot.  Oil-lite bushings in the valve guides would just about make an oilless head...but then there'd be nothing to run down the push rods and make it look important!
 

[sid]

just reading about oiling the rocker shaft and could not remembering oiling mine.but I checked and mine has the small grease cup on the end. just to show how many different ways they can make these listers/I am sure that parts are available to change over to the small grease cup.it would be a simple change and would save oiling.  on a daily basis/my engine is 6 years old so I guss they dropped the grease cup to save a few pennies/a nickel here and there and pretty soon you have a quarter.

[quinnf]

Hey Jack,

How's that cam end bearing oiler working for you?  Any wear on that bushing?  I saw your idea and did the same.  Drilled the oil cap and pressed in with epoxy a 16 ga. finish nail (all I had handy).  I'm getting a little oil leaking from the gasket on that end, so it seems to be doing something.  Just wondering if you've checked the wear on the bushing yet.

Sid, seems each manufacturer has different priorities.  Like yours, my Ashwamegh has bushed rockers and a grease cap on the end of the rocker shaft, though after I read Jack's last post, I wonder if it's hardened. 

Quinn

[hotater]

Quinn and all---

My cam bushing on that end seems to be doing will, the wear at the other (fuel pump) end will soon take out the off-side, too.  I'm going to make my own from oil-lite manganese bronze.

The Indians seem to have trouble truing their grinding wheels.  Magnify any ground part and you'll see a 'Herringbone/washboard' pattern.  that means there's highs and lows.  Some say it holds oil better, but I say it puts more stress on less area.  Maybe they balance out.  All I know is that the BEST engines have accurately ground shafts and they seem to last longer.  I'll regrind and make bushings to fit as things need it.

Here's something neat--
http://cgi.ebay.com/FUEL-FILTER-CHROME-GLASS-VERY-HIGH-QUALITY_W0QQitemZ8022491938QQcategoryZ9903QQrdZ1QQcmdZViewItem

[hotater]

This morning I went out to crank the Lister as every morning, nearly, for seven months.  On shutdown last night there was nothing at all unusual.

My usual 'below 50*F start' is to check oil (ok), squeeze water hose and watch the overfow (open),  set the valve release, release the rack, squirt one bit of ether through the air cleaner, crank hard and getting harder for three squeeks of the fuel injector, then rotate the valve lifter and lock it down as the start handle slides off.  It's  NEVER failed....until this morning. 

I heard a hiss from the air cleaner this morning....it surprized me so much I quit cranking and just kinda STARED at it for a minute....What de H....?

I had a piece of aircleaner screen sucked into the intake one time but I heard that weirdness and shut it down and found the problem...AND, I'd put a piece of hardware cloth over the intake to prevent it happening again.  I knew this had to be a valve problem, and on the intake side.  It either had to be a valve that suddenly quit seating or a cam lobe came loose, somehow.

By the watch, it took an hour and a half to take it apart, drive out the old valve guides, clean the TAR out of the intake and a tiny bit of carbon from the exhaust ports, install new guides, lap the valve seats, de-carbon without pulling the piston, reassemble and start on the first try.  Ninety minutes.

It's true, I have other gensets that run a wire brush and air compressor and lights....it would NOT be a good idea to have nothing but a Lister to run mamma's iron lung, but this kind of repair job without having to go to town and nothing in the freezer thawing is a GOOD thing.

HAPPY NEW YEAR!!!

Both valve guides are drive-ins....warm the head and hose the guides with propane and they drive right in.  DON'T use the flang on the guides to drive with, make a brass punch with a half inch hole in the end so you don't bugger the guide.
  Valve stems are 11 MILLIMETERS (.433).  That's the first metric thing I've found.  I'll have to order a reamer to do my bronze bushings.

Both my valve guides were loose but the intake side was SLOPPY....especially fore and aft.  The action of the rocker pushes the lashcap a little sideways as well as down.  NO wonder it didn't start!!