why does the 45 turn over so hard?
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Topic: why does the 45 turn over so hard?
Posted By: JM
Subject: why does the 45 turn over so hard?
Date Posted: 29 Jan 2011 at 8:05pm
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Several years ago grandpa overhauled the 45 with a engine kit he got at some auto store like NAPA or somebody like that. He told me he got a good deal on it because it was a left over they had for a long time. It was for a cotton picker or some kind of harvester, cant remember. Ever since after the engine is warm and you shut it off, the starter will barely turn it over the compression stroke. You have to make several attempts with the starter until it will roll over compression and then it starts instantly. Cold, it seems to roll over ok. Is something to tight or is it just from higher compression? Runs good , been like this for years and nothing has come apart. Still 6 volt. Should we try a 8 volt or just convert to 12? I wonder if he has the timing to advanced. JM |
Replies:
Posted By: CTuckerNWIL
Date Posted: 29 Jan 2011 at 8:13pm
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It could be higher compression. If you were to check the compression that might give some better idea why it does this. Could be a weak starter, poor ground, or a bad or undersized cable or even a timing issue. Some say you know the timing is right if you have the engine at operating temp and run it to high idle, then back of all the way, it should backfire once or twice.
------------- http://www.ae-ta.com" rel="nofollow - http://www.ae-ta.com Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF |
Posted By: mlpankey
Date Posted: 29 Jan 2011 at 8:17pm
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I am going to say somethings to tight. try twelve volt battery to the starter ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Jacob (WI,ND)
Date Posted: 29 Jan 2011 at 8:31pm
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Just a thought, If you tried to hand crank the engine, both when cold, and then once warmed up, you might be able to see if it is really harder to turn, or if something else is the culprit (like starter or wiring etc...) Not sure if this helps, but might eliminate some things.... I was going to guess something is too tight as well, but if it's been going this long, maybe not..... Leads me to think something electrical maybe. If everything is good, there is no reason 6 volt won't work properly. It was designed that way from the factory, and has worked for 50 years, if maintained and fixed, it will work for another 50 years, my humble belief.
------------- Jacob Swanson 1920 6-12; 1925,1926 20-35 longfenders; 1925,1926 15-25's; 1927,1929 20-35 shortfenders; C; B's; IB; WC's; WD; WD45 |
Posted By: JM
Date Posted: 29 Jan 2011 at 9:12pm
| What would get tight? I not sure but I think 45 bearing are non shim type arent they? I remember him saying the crank was guaged and had no wear on it so I know he didnt have it ground. I will see what the compression is when I get a chance. Any idea how much 6 volts can handle? It doesnt seem like it turns hard until it comes up on compression. |
Posted By: tractorkid1
Date Posted: 29 Jan 2011 at 9:23pm
| I would have to agree with ctucker and jacob on it being an electrical issue. Bad grounds will cause major issues with 6 volt systems. Another thing that happens with these old machines is the starter and ground cables get replaced with 12 volt cables. This is a no-no. The smaller cables won't let enough current get to the starter and will cause hard starting. If it was my machine I would clean all connections. Pull the starter out of its hole and clean the hole and the backside of the starter. Use electrical contact grease on all of these surfaces to ensure a good electrical path ,especially on that single jam nut/bolt that holds the starter in place. Ron |
Posted By: JC-WI
Date Posted: 29 Jan 2011 at 9:45pm
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Well I remember starting our 45 in winter, you better have her started by the third turn because if it had to turn over the 4th cylinder, you better have somebody on the crank or get a boost. Was that way until the dad went to change oil in it and got side tracked and started it up and ran it long enough to hook the spreader up nd start backing the spreader under the cleaner. It never had that top end compression again and still hasn't been apart either... But the engine should be rebuilt because it now smokes and uses oil.
And it did dyno 45 hp on the pto.
When the engine was warmed up, it would only take one piston over and it would be running. 25-30 years ago, I changed it over to 12 volts and alternator and put a resistor ahead of coil wire.
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Posted By: Dave in il
Date Posted: 29 Jan 2011 at 9:46pm
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After all these years if something was to tight I would think a problem would have developed other than hard starting. I assume this has been a working tractor since it was overhauled.
More than likely the 6 volt starting system is the culprit. If the starter is still original it could need rebuilding, if your cables are original they may need replaced. With "proper" maintainence (as in like new condition) the 6 volt system is adequate to start the tractor in most conditions. However unless you want to keep the tractor original, changing it to a 12 volt will start the tractor much easier with less maintenance headaches.
I have a WD with an 8 volt, a WC with a 6 volt and a WD45 with a 12 volt and the WD45 starts much easier. The starter and cables on the WD45 are the same ones that were on it when it was changed to 12 volts in 1983, it has a one wire Delco alternator.
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Posted By: Steve M C/IL
Date Posted: 29 Jan 2011 at 11:33pm
| I vote for higher compression being the culprit.The D17's were higher compression and 12 volt starters.45's were marginal for hot starts on 6 volts with 6.5(stock) compression.Raise the compression and you'll be crying if you kill it hot. |
Posted By: Brian Jasper co. Ia
Date Posted: 30 Jan 2011 at 12:28am
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The hard to start hot sounds like my CA was before I found out about the battery cable size requirements of 6V vs 12V. 6V needs a minimum of 02 gauge with 00 being best. Cables for 12V are typically 04 to 06 gauge. To do the same work, a 6V system will require twice the amps as compared to a 12V system because you have half the volts. More amps need thicker cables. ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 12:36am
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And that starter would draw even more current on 12 volts if it wasn't limited by the cables and the battery. One other place to check. The distributor centrifugal advance mechanism. Usually its not advanced past top dead center while cranking or it will stall the starter or kick back on the crank and break the cranker. If the mechanism is rusted up, it can advance while running and ooze back to no advance after siting a while. That gets worse when the springs the centrifugal weights pull against rust off and the WD 45 is more than old enough for that to happen. It might be just a lack of lubrication usually applied to the felt in the center of the shaft when the distributor rotor is removed. You can get a feelling for stickiness or stiffness by trying to rotat the rotor with the discributor cap off. It should rotate towards advanced tolerably easy and return to the initial position instantly on its own when released and it should not be possible to rotate more retarded than the springs return it. Else it will be fireing on the compression stroke and WILL stop the starter. Gerald J. |
Posted By: Brian Jasper co. Ia
Date Posted: 30 Jan 2011 at 12:54am
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Gerald, not according to Ohm's law. If the only change is volts, load staying the same, amps will drop. ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: WC Fields(N_ILL)
Date Posted: 30 Jan 2011 at 8:52am
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Gerald is correct. 6v / 1 ohm = 6 amp 12v / 1 ohm = 12 amp ------------- 37 WC 49 WF 53 WD 67 D15 |
Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 10:03am
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I learned about ohm's law about 56 years ago. Hasn't changed yet. I learned about motors a little later. The starter is a series wound motor and its current when stalled (as when power is first applied) is limited temporarily by inductance of the windings and the wiring, but soon (in a couple millesconds) is limited only by resistance and with 12 volts applied that current will be twice what it was at 6 volts. The torque applied to the DC motor shaft has several variables affecting it. There's the current, torque goes up proportional to current. More current, more torque. Torque goes up according to the number of turns in the armature that are in the magnetic field from the field poles. More turns, more torque for a given current. Then until the field poles saturate there's more torque from greater field current. Since in the series wound starter motor the field current and the armature current is the same, more terminal current means more torque. Current is reduced when the armature is spinning to generate a counter EMF called back EMF, voltage in the armature windings that opposes the flow of current in the armature to reduce the current. Which reduces the field current and the back EMF so the effect is less in the series motor than in the shunt motor. The series motor has a useful characteristic of being nearly constant torque so the load determines the speed and a series motor with enough power (usually long about 2 or three real horsepower rating) with no load will reliably self destruct by turning so fast it throws the windings out of the armature slots. That constant torque is why small tools use a series winding for high speed, why starter motors have been series winding for most of their history, and why trolley and locomotive traction motors are series wound. These can all work with shunt wound except that the shunt wound (or permanent magnet field) motors tend to have a constant speed characteristic and if slowed by load they drop the back EMF and drastically increase the armature current. That would make the trolley climb a hill as fast as staying on level track, but would work at pulling the power plant to its knees. The AC induction motor is considerably more complex and because its shaft speed is set primarily by the AC frequency, and the shaft load is usually set by the shaft speed, its power tends to remain constant with varying voltage and so low voltage makes it demand higher current. But its operating voltage for a constant frequency does not vary 2:1 except for very small motors. Yes, doubling the voltage and holding the power constant takes half the current, but almost always that holding the power constant requires rewiring or rewinding the load device to change its resistance and that's true of an AC motor with reconnecting paralleled windings into series windings. Both AC and DC motor operation is complicated by saturation of the magnetic core which tends to happen on shunt wound DC and all AC a few percent above the rated name plate voltage, depending on how conservative the design is. Gerald J. |
Posted By: mlpankey
Date Posted: 30 Jan 2011 at 4:09pm
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Ohms Law . George Simon Ohm a intelligent man. Batteries are rated in volts and cranking amps. Starters have field windings rated in kw. What a six volt 1000 ca battery cannot turn over sufficiently without dragging and heating the insulation up to the melting point. A 12 volt 500 ca battery will turn sufficiently and cranking time is less building less heat . The AC WD ,WD 45 starter windings will handle 28 volts at 500 ca . The switch has to be changed to a lug terminal and a Warren winch solenoid has to be utilized but it will start a 400 Ci engine at 15.1 compression ratio. Mitch Pankey not a very smart man but one who gets by. ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Thad in AR.
Date Posted: 30 Jan 2011 at 4:26pm
| I don't wish to hijack this post but I have a question. My thomson B has a rebuilt motor with aluminum flat top pistons. They were all I could find at the time. It cranks real hard. The starter was rebuilt but it didn't help and it has a new 6v battery. I did find out that it will crank easier with the ignition switch off (distributer ignition). Why is this? You can crank it over and hit the switch and it just about stops. It has new cables but maybe not big enough. |
Posted By: smuggler
Date Posted: 30 Jan 2011 at 4:27pm
| timeing? |
Posted By: mlpankey
Date Posted: 30 Jan 2011 at 4:35pm
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Amps = 1000 X kw/volts Ac starter windings 2.4 kw 2.4x1000=2400/12volts=200
( ) /6volts =400
not a very smart man just one who gets by scratching his head alot. Thad ark. ignition load and timing advanced trying to light it off. ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Brian Jasper co. Ia
Date Posted: 30 Jan 2011 at 5:04pm
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Like Mitch is pointing out is the load has not changed, the volts did. Now I'll throw in another variable. Resistance changes with heat. We have less current flowing on 12V so the starter isn't getting as hot. That means the resistance doesn't change as much. Convert it all to watts and see what happens... ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: Brian Jasper co. Ia
Date Posted: 30 Jan 2011 at 5:13pm
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Another way to look at it can be compared to modern automotive electrical applications. Last time I checked, a fully loaded Suburban held the record with 28 modules all consuming 12V. When any programmable module has to be reflashed (programmed) it's key on engine off. 28 modules typically will run the battery down to the point of no start in about 10 minutes. That same Suburban has a 140 amp generator. If it were using 6V, the current use would easily double. Where we gonna put a 300 amp generator, and how much engine power is it gonna use? ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: Ed (Ont)
Date Posted: 30 Jan 2011 at 5:58pm
| Lots of info here - almost enough to fly to the moon. Just make sure you have 2 good heavy cables for power and ground not the 12v auto stuff. Time the engine with a light to the F mark thru the inspection hole. We put up with all the same symptoms you describe for 50 years. I got the tractor & went thru the basics. Starts any time now with 15-40 oil and no heat or help of any kind. Sat from Oct to mid Jan 2011 in outdoor shed and fired up in 2-3 rotations. 6 volt UAP battery about 5 years old now - replaced that as soon as I got it. WD45 by the way. 1954 model. |
Posted By: mlpankey
Date Posted: 30 Jan 2011 at 6:27pm
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Why is it when you whip out the correct formula someones feelings get hurt and they make a wise crack about knowledge? ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 6:27pm
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Motor ratings are based on winding heat. Heating windings doesn't cause instant failure of wire or insulation, but the heat does. A given starter on 12 volts will produce (if the battery and cable resistance isn't a factor) twice the torque it will on 6 volts and will do 4 times the torque on 24 volts. Any engine (neglecting spinning it so fast the magneto impulse start mechanism doesn't work) will start faster when spun faster, so higher voltage on the starter shortens the time it heats and if that time is reduced faster than the current went up from the higher voltage the starter will last longer on the higher voltage. Normal operating currents in a motor winding are a long ways below the current required to melt the wire. Its the insulation and the brushes that will give up first because the current has to go through the brusses and they aren't nearly as conductive as copper. When you go to a battery with smaller cranking amps, you have the same potential available at the chemistry and the plates but more resistance from smaller plate and connecting bar area. When you use cables made for import sewing machines the resistance of the 6 and 8 gauge wire drops significant voltage and so limits the current when trying to draw 200 or 400 amps through the small wire. Heats that wire too and its connections which you can often find with a soon to be burned finger feeling for hot spots. Gerald J. |
Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 6:29pm
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A 300 amp 6 volt generator is going to take the same shaft horsepower as a 150 amp 12 volt generator or a 75 amp 24 volt generator. And fit in the same space if properly done. If I was to do a 300 amp 6 volt generator/alternator, I'd use the same wires as I did for the 24 volt, I'd just hook four wires in parallel in the 6 volt winding but use the same winding space with the same packing factor. Gerald J. |
Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 6:35pm
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The Thompson B that cranks much harder with the distributor powered is the classic sign that the idle timing is too far advanced. Either its just too far advanced all the time or more likely like I described above, the centrifugal advance is stuck advanced from rust, lack of lubrication (that oil wick in the center of the shaft under the distributor rotor is there for that purpose only), or the springs actually rusted off. My dad had a 73 Torino that would stick advanced and the starter could barely crank it over. Vibration made it time right once it was running and it might be months between those occurances. And one was the day I sold it for him in 1980. 351W I think it was. It cranked like the battery was almost dead. Time to work on the distributor advance mechanism and the basic timing. It probably won't improve on its own if the problem is grunge or rust. Gerald J. |
Posted By: mlpankey
Date Posted: 30 Jan 2011 at 6:35pm
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Interesting I have never seen the service factor on a starter. Insulation on a number 2 wire will handle 200 amps but not 400 amps. welding lead is expensive! Interesting thing about tractors centrifigual advance is they are all in at 800 rpms. ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 8:30pm
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The advance curve depends on the tractor, maybe 800 rpms at the distributor, but more like 1800 to 2000 rpm on my 4020 I think because its supposed to be timed at 2200 RPM. Gerald J. |
Posted By: mlpankey
Date Posted: 30 Jan 2011 at 8:46pm
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Pardon me I thought the question or post was on a Allis Chalmers wd45 with a delco remmy 1111 series distributor . Maybe he should ask on the Johny popper forum. A engine requires more spark advance at higher rpms or to be timed for the highest rpm. ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 11:53pm
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I don't have the advance data for the WD45 engine. I presume a good shop manual like the factory one has reliable data for that. The cranking problem can come from advance before top dead center at cranking speed, that shouldn't be a design problem but can be a rust or grunge problem in the distributor sticking it advanced. All engines need more advance at part throttle than at full throttle for good throttle response and part throttle efficiency. Very few tractor gas engines ever got that. Gerald J. |
Posted By: mlpankey
Date Posted: 31 Jan 2011 at 10:15am
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I really dont see part throttle response being a issue on a tractor nor is it on round track and drag race engines which throttle seams to be operated the same ,at least when I am in the seat of either one of the three. I ran the advance locked out and total timming on the pulling tractor as I did when racing. ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: SeanD17
Date Posted: 31 Jan 2011 at 10:30am
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I had the exact same symptoms with an Oliver 1650 after doing bunch of work on it and it was 100% a timing problem problem. I would definately look there first, if you been using it awile this theory is also supported because something mechanically that much too tight would have failed of at least be showing other signs of problem by now. ------------- D14 N.F., Series lll D17 N.F, 3 Bottom Snap Coupler Plow, 4 Bottom Slat Snap Coupler Plow. |
Posted By: Gerald J.
Date Posted: 31 Jan 2011 at 12:29pm
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Farm tractors don't spend their entire operating time with plow in the ground geared fast enough to pull the tractor down a bit off the governed speed. E.g. working at the maximum available power. Lots of farm work involves less load, like going from shed to field, mowing hay, raking hay, hauling wagons, cultivating, planting. Its these lightly loaded conditions where some more advance would improve throttle response, e.g. not stumbling with taking on a load or climbing a slope or anytime the load changes and the governor calls for more power. Gerald J. |
Posted By: mlpankey
Date Posted: 31 Jan 2011 at 12:53pm
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If its a wd45 allis its all in at 800 rpms . So after 800 rpms there is no more advance. 300 or 400 rpm is starter cranking rpm . Safe to say the advance is a narrow rpm range for any field work . ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Gerald J.
Date Posted: 31 Jan 2011 at 4:03pm
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Are you sure that's crankshaft speed or distributor speed? Most distributor specs are based on distributor speed, not crank speed. Gerald J. |
Posted By: mlpankey
Date Posted: 31 Jan 2011 at 4:23pm
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I am certain its engine rpm . every recurve kit i have used is based on engine rpm .Are you certain? ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: Brian Jasper co. Ia
Date Posted: 31 Jan 2011 at 5:10pm
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Hmm, been to 7 county fairs and never saw anything like it. Up until the time distributors started going away for spark timing, every engine I've seen used crank speed for everything. Like someone's tag line is "fill the back of the shovel and the front will take care of it's self". Who cares about dist speed? The load is connected to the crankshaft, not distributor... ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: DaveKamp
Date Posted: 31 Jan 2011 at 10:04pm
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Back to the original question... IF you find that ignition advance has no noticeable effect on starting when hot, the next thing I would suspect, is a coolant leak into the chambers. I'd THINK that you'd've noticed the coolant level falling, but making assumptions... well... |
Posted By: Dave in il
Date Posted: 01 Feb 2011 at 9:23am
I doubt it's a mechanic al issue, after all these years a mechanical problem IMHO would have gottem worse. If your timing is set right and your timing advance in the distributor is working and it still starts the same, borrow a 12 volt battery and swap your 6 volt.
Don't turn on the ingnition just pull the stater, if it cranks the way you want, you can put a resister in front of the coil (or just get a 12 v coil), change your light bulbs and find a 12 volt alternator and it's cured.
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DaveKamp wrote:Posted By: mlpankey
Date Posted: 01 Feb 2011 at 10:04am
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Jm Take a chisel with a sharpened edge . make a reference mark on the distributor base and the housing in which it sets. Now then after having a reference mark to where the distributor was originally . Turn the distributor If my memory serves me correct clockwise to retard .to where the line you made on the distributor looks as if it would be beside the the mark on the base . Depending on how fat your line is it should take a minimum of 2 degrees of timing out the wider the line the more degrees it takes out or puts in. This will let you see if it starts easier due to ignition timing. I still however suspect the piston rings being the culprit by your description of it doing it more when hot. Reason being is I ran a stock starter with more battery voltage and fixed timing on my puller. . You can also check the distributors advance with a advance degree timing light . The advance should be all in at 800 engine rpms or by removing the distributor and making it advance the plates in your hand . I still suspect piston rings though. ------------- people if they don't already know it you can't tell them. quote yogi berra |
Posted By: DaveKamp
Date Posted: 02 Feb 2011 at 12:23am
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ML... You thinkin' that mebbie the rings are warming up and binding due to lack of proper gap? That wouldn't sound out-of-place, but I wouldn't think it'd cause that much drag without having a profound effect on the color of the crankcase oil, and of course, long-term compression... Here's another thing that may, or may not have substantiality... The ground connection point... I was having starting probs with my '50 WD... regardless of conditions, it cranked slow, like the battery was dead. Had decent spark when hand-turning, but when the starter motor was running, it'd have miserable spark... at least, until the moment you released the starter switch. After changing battery, cables, and starter switch, I decided to move the ground wire from where it'd been installed (on the transmission top cover, IIRC) to the starter housing somewhere, and it totally changed attitude. Obviously, the conduction path from tranny top plate to starter wasn't as good as someone had hoped. At 6v, the starting circuit is VERY DEPENDANT upon low resistance to work properly. |
Posted By: mlpankey
Date Posted: 02 Feb 2011 at 10:31am
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I think either a ring or two were cracked on installation or they are possibly gualded stuck to the ring lands possibly from butting together. may have came with the wrong set of rings per the pistons ring land depth in the kit even. I am not saying his grandfather did this . I am just saying that I have seen some rationalize that a tight ring end gap is better and that .010 long file fit rings were made to take up cylinder wear. Again this is general not implying his grandfather did or didnt . ------------- people if they don't already know it you can't tell them. quote yogi berra |