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Introduction following is part 2 of Quinn's report. As we know, India is slow to embrace QC, this means that you'll find little things that may not be perfect, seldom discussed in forums, webpages, or even British Lister manuals is build tolerances. I guess they thought this was more about manufacture, and they'd be doing that, but for many of us, we attempt to re-manufacture at a high tolerance when we can. We believe the more accurate we can make things, the longer it may live; but we must keep in mind, some stockers have 8000 hours on them already! Perhaps they are lucky? I tell people they are foolish if they don't make the basic checks prior to putting an Indian engine in service, what tolerances did the British allow? Many of us who have the time and the equipment attempt to get things as accurate as possible, and some of us are not quite sure where to stop. For your reading pleasure, here's one man's approach to making his kit engine the way he wants it. Let us hope he doesn't paint it John Deere Green! All the best, George B. ---------------------------------------------------------------------------------------------------------------------
July 22, 2006
Gentlemen,
Here’s the proof. I removed my other engine from its generator bed and bolted down the test engine. After filling the crankcase with oil and evicting the air bubbles from the fuel lines and filter, I engaged the starting handle and gave it a whirl. I closed the decompressor and the engine chugged to life. The governor linkage was initially set too high and I had to close the fuel rack by hand. Best to warn customers to start the engine with a hand on the linkage, then turn the adjusting screw until the desired speed is reached.
The engine settled down to a smooth and steady beat. No different in action or sound than my Ashwamegh. Tappets rotate about ½ turn each time they lift, the governor seems to be working, and there are no fuel leaks. Even the petcock on the bottom of the tank doesn’t leak a drop. And the engine seemed to be well balanced. My Ashwamegh is a very smooth running engine, and this one is no rougher, and possibly a little smoother.
I’ll eventually transfer the generator from Old Silver to this engine and hook it up to cooling water so I can put a load on it. But for now, everything is working just as it should. No surprises.
Quinn.
Beta Test Part II
September 17, 2006
Gentlemen,
“No surprises,” I said. Sometimes your words come back to haunt you. A number of us have been going back and forth recently about how and what to check on these engines to make sure they are set up correctly. And it appears that while things may look right on the surface, problems may continue to lurk in hidden places. Sad to say, but it appears that there might be deliberate concealment of dirt and misfit parts by assemblers while their supervisors are either absent, incompetent, or corrupt and intentionally looking the other way.
However, these engines are very much individuals. One thing that seems to be consistent in the quality of Indian Listeroids is their inconsistency. One engine appears to be just about perfect and the next crate opened contains an engine with a piston wrist pin full of sand. So until India decides to stop paying lip service to quality by citing I.S. (Indian Standard, i.e. “good enough for India”) these engines should continue to be checked out thoroughly before being put to serious work.
The British built Lister engines have attracted a following by virtue of their excellence in design and quality. Parts were carefully made from good quality and appropriate materials by skilled machinists. They were installed and fitted with care, and the result was an engine that seemingly runs forever.
The Indian “Listeroid” shares the same basic design as its English parent. That design has even arguably been improved by the addition of tapered roller bearings (TRBs) and the elimination of the unnecessary Freeman-Sanders compression changeover valve, which Lister themselves did away with in 1958 with the introduction of the 8/1. That engine featured a single combustion chamber plug and a higher running 17.5:1 compression ratio, which is more in line with that of modern diesels.
So even with the known quality problems of these engines, we know the design is a good one, and the parts are largely of good quality. However the assembly and fitting of the parts is one area that must be improved, or perhaps the engines should be imported as parts rather than subassemblies. With some care and a little work, and in extreme cases with help from an engine machine shop, the experienced do-it-yourselfer can come up with an engine that is fit right, and one that should run for a long time.
Disassembly
I began disassembling the engine by removing the gib keys and the flywheels. I found that at 140 lbs., the flywheels that come with the PS kit weigh about 15-20 lbs. more than did those on my Ashwamegh. So I felt better about how much difficulty I had lifting these flywheels out of their crate than I did moving the Ashwamegh’s 125 lb. flywheels a year ago. It wasn’t just advancing age after all! I e-mailed an inquiry to David Edgington about the weight of the original Lister 6/1 flywheels. After some checking, he replied that the original 6/1 flywheels weighed 120 lbs.
Next came the fuel tank, fuel lines and fuel filter. Then out came the fuel injector and the high pressure fuel line. I placed the fuel injector and its copper gasket in a clean zip lock plastic bag. Keeping small parts including nuts, bolts, pins, keys, etc. in plastic bags is a good way to keep them from getting lost. And if you place all the small parts from an engine subassembly, such as the cylinder head, in the same bag, reassembly proceeds much faster because there are fewer parts to sort through on the way up.
Next, I took the rocker arm assembly off the head, and removed the push rods and set them aside. Then the head nuts came off and I removed the head.
Next, off came the camshaft end cover and there is where the fun began. The Indians don’t seem to understand how tapered fittings work. That’s obvious when you look at how they “fit” gib keys. When the mating surfaces of a tapered pin and seat match correctly and are clean and free from oil and grease, all that is required to set the pin is a firm tap from a hammer. Some folks insist on lightly peening the small end so that it cannot work its way out. But to mash both ends of the pin to nearly double its original diameter is crude and unnecessary. The parts can also be dusted lightly with chalk or lime dust to provide a little more friction, but a firm tap should be all that is necessary to keep the parts together.
I used an abrasive cutoff wheel in a 4.5” angle grinder and cut off BOTH ENDS of the tapered pin. The pin had been so deformed, it was impossible to determine which was the large and small end of the pin without cutting both ends. Once I found the small end of the pin, I tapped it out using a 32 oz. ball peen hammer and a drift pin, but it wasn’t easy. I really had to whack the pin to get it to move and was afraid I would shear off the end of the camshaft doing so. Fortunately the pin yielded, and the camshaft held, but my patience didn’t. I was so annoyed I was in no mood to snap a picture.
I disconnected the linkage between the governor and the injection pump on the other side of the engine and removed the camshaft after first removing the tappets and guides. Below is a picture of the camshaft end bushing.
Looking inside I discovered a very small amount of dirt, but more bothersome to me was the poor finish of this bushing. It looked like it had been drilled on a cheap drill press. There are rough spiral marks in the bore that look like what you’d get if you drilled a deep hole without periodically withdrawing the bit and blowing out the chips. However the part of the bushing that rides on the camshaft is the outer end and as can be seen in the next picture, that surface is acceptably smooth. The camshaft showed no wear marks after ½ hour of total run time.
The bushing measures 3.005”
long, 0.880” inside diameter and 1.375” outside diameter. The camshaft is
0.875” diameter, so the clearance is 0.005” a decent slurp fit.
It would be possible to improvise a puller for the bushing with a piece of threaded rod, a 1.5” pipe nipple and a couple of nuts and washers, and I’ve given some thought to replacing the bushing with either an oil-impregnated bronze bushing, or possibly a piece of brass milled to accept a ball bearing. That would ensure that the cam bearing was adequately lubricated, but that idea might fall into the same category as needle rocker bearings and carbon fiber pushrods. A clean steel bushing should last almost forever so long as it gets lubricated.
Next, I rotated the crankshaft until the piston was at BDC and lifted the cylinder off the piston. Here’s what I found beneath the cylinder:
What the heck would that be? Two 0.0075” half gaskets had been stacked on the starting-flywheel side. Note the tears in the shim for the stud holes. That indicates the shims were placed beneath the cylinder after the cylinder had been placed on the crankcase. I had been alerted to the existence of the yellow half-shims by Jack Belk, and John Ferguson e-mailed me that he had seen these half-shims before, too.
Evidently someone in India was paying attention to quality. He evidently thought the cylinder casting or the cylinder sleeve was not square and shimmed up one side 0.015”. That’s cause for worry because if the cylinder is not square to the travel of the piston, it might scuff against the liner at the bottom and/or top of its travel, or excessive side loading might prematurely wear the wrist pin bushing and/or rod bearing. I took the cylinder to a friend’s machine shop and placed it on a ground slab of steel and using a height gauge determined the cylinder base and head surfaces were parallel to each other without any shims. However that doesn’t mean that the cylinder sleeve is perpendicular to the base.
Next, I replaced the piston with rings into the cylinder and lowered the cylinder onto the crankcase WITHOUT any base gasket or shims. Metal to metal. I also remounted the crankshaft in the TRBs and torqued everything up to spec. Because the shim gaskets were absent, at TDC the piston projected slightly above the rim of the sleeve.
I took the edge of a combination square, sighted along it by eye, then ran it across a sharp mill file a couple of times to be sure the edge was flat and balanced the straightedge on the top of the piston. I slowly rotated the crankshaft until the piston backed down inside the cylinder liner, leaving the straightedge balanced on the liner with a sliver of light gleaming between the piston top and the bottom of the straightedge. The sliver of light was even, side to side. Had the piston been out of square with the cylinder, by even a couple of thousandths, it would have been visible. So the piston is square to the liner, the crankcase is known to be square and the cylinder base and head surfaces are known to be parallel. So how come the Indian assembler thought he needed to shim up one side of the cylinder by 0.015”?
Next I pulled the cylinder sleeve. If you have a drill press, you can easily remove the sleeve by inverting the cylinder and placing it on a couple of pieces of wood on the table. I cut the corners off a piece of plywood to just fit the skirts of the sleeve and cranked the table up until it was resting against the chuck.
Then I cranked down on the spindle, and “Clunk!” out came the cylinder.
Once the cylinder sleeve moved about an inch the O-rings slipped off a ledge and the liner dropped out. Piece of cake.
There was a lot of dirt/grit around the cylinder sleeve, amongst the O-rings, and especially in some of the nooks and crannies of the cylinder casting. That shouldn’t be a problem because that grit would never see the inside of the crankcase, and it might even wash out of the water outlet once some vigorous convection currents get going. However in the interests of total disclosure, here are pictures of the sleeve and the cylinder casting just as they appeared at separation.
Note the location of the double grooves near the bottom of the sleeve for the O-rings and the inverted ledge machined near the top of the sleeve.
Looking down the bore of the cylinder casting in the picture below you can see a ledge machined into the cylinder casting that engages another ledge that projects out from the sides of the sleeve. These ledges must be absolutely clean or the cylinder will not be square to the casting and the lip will project higher above the cylinder casting than it was intended to project. You can see the grit that was left on the ledge, which raised the cylinder sleeve appx. 0.005” above where it sits when the ledges are clean.
If the cylinder liner is found to project more than 0.008” - 0.010” above the surface of the casting, the head gasket might leak coolant. The projecting lip of the sleeve can be milled down, or either of the ledges might be machined. This is a job for an engine machine shop. Find an independent auto mechanic and ask them who they recommend to do engine machine work. These sorts of tasks are routine for them and shouldn’t be expensive. Auto machine shops are also set up to quickly assess the squareness of castings and cylinders.
The height of the cylinder sleeve was measured at 0.030” above the cylinder deck, so this is a job for a machine shop. However another way of solving a height problem would be to obtain some shim stock from McMaster.com or equivalent, and make your own shims. Five dollars and change for an 8” square of 0.015” brass and a little elbow grease could save some money that would otherwise go to a machine shop.
TRB Housings
Next task was to remove the crankshaft. I removed the rod bearing cap, and pulled the piston and connecting rod through the top of the case and set them aside. I noticed the crankshaft was a little stiffer in its bearings than I would have liked it to have been, so it was clear that whoever assembled this engine wasn’t very careful to avoid pre-loading the TRBs. The specification for the TRBs calls for 0.005” - 0.010” end play in the crankshaft. Anyone who has replaced front wheel bearings in a car knows how to set them up. You tighten the keeper nut until there is no wobble in the wheel, then continue tightening until you can detect a little drag, then loosen a bit, then tighten again until you feel drag, then loosen . . . then lock it down when it feels just right. However adjustment on these engines is effected by the number of paper shims that are placed between the crankcase and the TRB housing flanges.
I removed two 0.018” (rust colored) shims from the left side TRB housing and one 0.018” and two (yellow) 0.0075” shims from the right housing. I think there probably should have been about another 0.020” there to get the proper spacing for the bearings, but I’ll address that when I’m reassembling.
With the TRB housings removed, the crankshaft came out and I set it aside in a safe location with clean rags tied around the crankshaft pin to prevent any damage to its polished surface.
Oil Pump and Lines
I removed the oil pump and oil lines from the crankcase. The oil distribution system has a crossover tube that lies just inside the big crankcase access door. While I was disassembling the engine in preparation to strip the paint, I puzzled for a while at how the crossover tubing could be disconnected. It appeared that there must be a compression fitting somewhere. Otherwise I couldn't see how to remove it. The picture below shows the relationship of the components.
By the way,
what appears to be buggered up threads in the lower left stud hole in the
picture is actually the remains of a rubbery thread sealer the thoughtful
assembler placed on the threads of the stud during assembly. Since water may
find its way into the stud cavity from a weeping cylinder head gasket, it’s a
good idea to seal the threads when you replace the studs to keep water from
dripping into the crankcase.
Here's a shortcut taken that nobody is likely to find until they tear an engine apart. Both ends of the crossover tube were ground to a taper but were never soldered. No compression fittings, no tapered seats. One wonders how much oil delivered by the pump leaked out of these fittings. It is fortunate that this engine is splash lubricated and that the oil pump is really not necessary for effective lubrication of the TRBs.
When this engine goes back together, I'm going to redo the oil distribution system and use proper fittings with either flared steel or copper distribution lines.
Stripping Paint From Engine Castings
While I was removing small parts from the engine, I had been experimenting with different methods of removing the paint, gray primer, plaster filler and some rust-colored filler (brick dust?) that seems to be used everywhere on this engine. I finally settled on drain cleaner which is essentially sodium hydroxide (lye) available from Home Depot in 32 oz. (2 lb) bottles for just under $6 U.S. This is the dry, granular drain cleaner, not the liquid.
This stuff works best on parts that aren’t covered in oil/grease, so it’s a good idea to first wash really greasy/oily parts with paint thinner/kerosene/diesel, and then dry them with rags before stripping paint. (Dispose of the rags properly. You don’t want to start a fire with oil-soaked rags.) If you are really intent on doing it right, you’ll then wash the parts off in hot soapy water before subjecting them to the stripper.
Make sure you observe all the cautions on the bottle of drain cleaner. Especially be careful of your eyes. Wear eye protection when working around this material. Fill a 5-gallon paint bucket (plastic only) about half full of really hot water. Sprinkle a quarter to half of the bottle of drain cleaner in the water and stir it around until the granules dissolve. Then carefully lower the parts into the liquid. Don’t allow them to splash. Then continue filling the bucket with hot water until the parts are just covered. Then stir to mix the solution thoroughly. After a while the liquid turns any of several colors as the paint dissolves.
I left the cylinder and several small parts in the bucket for 24 hours. At the end of that time I removed the cylinder and hosed off the residue.
Here’s the result. Green paint gone. Gray primer gone. White plaster filler gone. Red brick dust gone. Bare paintable metal is all that’s left. If you place the parts out in the sun or give them a rinse with hot water, the metal will hold enough heat to evaporate the remaining surface water, minimizing any rust formation.
The Do-It-Yourself Hot Tank
While I was at it, I got inspired (carried away?) and decided I’d hot tank the crankcase, too. So I got a new 34 gallon plastic trash can (my old one has holes in the bottom). I placed a few bricks in the bottom to use as spacers, then with some help I placed the crankcase, stripped of everything removable, inverted in the trash can so the cylinder deck was resting on the bricks. Then I began filling it with hot water and added 1 ½ bottles (3 lbs) of drain cleaner.
The liquid bubbled like a witch’s cauldron. Lots of vigorous activity in there. Again, care was taken to ensure that no liquid splashed out, and the pilot light on the gas water heater in the background was turned off as a precaution. To my knowledge only cast iron and paint and sodium hydroxide were in the can, so I don’t know what was reacting to produce the gas bubbles. But it’s possible that flammable hydrogen gas was being produced, so it’s best to be careful and make sure there is plenty of ventilation available.
The next morning I lifted the crankcase out of the can and hosed it off. You can see in the picture below that the paint removal was not 100 percent effective after only 8 hours soaking. I was too eager to see results and the concentration of drain cleaner wasn’t enough to do the job in the time I allowed. There are still a few places where the paint didn’t quite come off. And two areas in the bottom of the crankcase held bubbles of air, keeping the caustic solution from reaching them, so I’ll have to strip them the old fashioned way. Next time I would use two full bottles (4 lbs) of drain cleaner and let the case soak a full 24 hours before removing. No harm is done to the metal by allowing it to soak a little longer.
While the parts are drying, some minor surface rust might form. The rust is very thin and can be wiped off with a rag. Without the paint, I was able to see the cast iron for the first time. This is really nice material. Very few voids or imperfections in the casting, and like good cast iron, this material isn’t very rust-prone.
Below is a shot of the inside of the crankcase. That nice smooth white paint that the Indian painter carefully applied is history. The bare casting remains. I poked around and found only one dime-sized area of grit behind the bumpout that holds the cam bushing at upper right of the picture below. Whoever prepared this crankcase did a great cleaning job before it was painted.
Ok, fun’s over. Back to work.
Sand Alert!
As I was drying the stripped castings I noticed that the inside of the main bearing housings were very rough. On closer inspection I discovered that the castings were coated with a very thick layer of casting sand. These parts were not cleaned before they were painted.
A close-up photograph shows the gritty surface.
The grit was removed in a few minutes by using a wire wheel in the chuck of a portable drill. Gray casting sand was removed from the surface, which is now ready for paint. But to really do the job right, the part should be shot blasted. To think this surface was next to the main bearings, concealed beneath a layer of paint would be unacceptable, were it made anywhere but India. And had the worker responsible for this oversight been employed by any company in the West, he’d be fired for doing such a thing.
Measurement of Cylinder Sleeve Squareness
I replaced the cylinder sleeve in the block and set it up on wooden blocks in order to test the squareness of the cylinder sleeve to the top of the cylinder casting. I used a piece of ½” machined aluminum as my straight edge and measured the protrusion of the cylinder sleeve above the casting in four places using brass feeler gauges.
This measurement will tell two things. First, it will indicate how square the sleeve is to the cylinder casting and it will also indicate how much I need to reduce the height of the sleeve. George recently indicated that the cylinder liner should protrude between 0.008” - 0.010” above the cylinder casting surface. It looks like most Listeroids have sleeves that protrude more than 0.010” and that may explain why so many people are plagued by leaking head gaskets. Before pulling the sleeve I measured its protrusion at 0.030” and I’m sure my Ashwamegh sleeve projects considerably higher than that. It’s possible some grit or a machining irregularity held the liner higher on one side than the other, so the earlier measurement needed to be confirmed.
Results, displayed in the drawing below, indicated that there was 0.001” difference between the front and back measurement (I call “front” the side where the camshaft is), and 0.004” along the axis of the wrist pin.
Now the shim is beginning to make sense, in a bass-ackwards way. Here’s why. The yellow 0.015” shims were placed beneath the right side (starting flywheel side) of the cylinder, raising that side by 0.015”, or perhaps less once the gasket had been squished down a bit (how much?) from pressure exerted by the head nuts. So the assemblers must have known that there was something not quite right about the level of the cylinder along the axis of the crankshaft and wrist pin. However, the right side measured 0.027” clearance, while the left side measured 0.023” so the assembler appears to have placed the shim under the WRONG side of the cylinder to effect an adjustment. I’ve known people like that.
So how far out of level is this engine? We can disregard the 0.001” front and back. That’s nothing. How ‘bout 0.004” along the axis of the crankshaft? That’s 0.004” measured 5” apart (on either side of the cylinder liner). The stroke of this engine is 5.5” so that’s about 0.0045” along the entire length of the stroke. I’m tempted to say that’s almost nothing, however when you’re interested in setting up an engine for longevity, and you’ve already got it stripped down to the point that even the paint has been removed, many things are possible. Engine machine work is not very expensive to have done, and there are LOTS of places that do it. I think I’ll run this one by an engine shop and see what they recommend.
Quinn
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