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My L654 Has Different Timing Marks?

JeepWagoneer

Registered
Hello All,

I acquired a Hesco Mobile Power Unit about a year ago and have been stumbling through repairing it. Everyone that looks at it (car mechanics I know) says the issue seems to be timing related and so I've looked at the countless threads about timing this engine on this website and noticed a couple of things.

First, I see a lot of reference to "T/M" and "S" marks on the generator fan (Took me a little while to realize people where talking about the "Flywheel.") I don't have those marks, instead I have two colored marks. One is yellow (or orange.. can't remember) and the other is white.

The white one I think is TDC and the Yellow one I think is the 16 degrees before TDC Mark or the "SPK" mark i see people refer too.

I've timed the Mag to both marks one of them it won't even try to do anything and the other it will always "Hit" on one cylinder but never actually start the engine (seems too retarded) I think the white mark is the one where it hits if I time the mag to that.

Known goods on the engine:
1) Makes good compression (Farmers trick I use where the compression blows my thumb off spark plug hole I don't have any fancy gauges) :D
2) when the starter cranks the engine it makes about 20 PSI of oil pressure
3) Sparks on all cylinders

Interesting note, It won't run on gasoline, propane, or starting fluid it will only ever "try" to start on propane (That's the only fuel its set up for.) If you try to start it normally it will putt on 1 Cyl and then die. If you try to add starting fluid it wont do anything until the starting fluid clears out, then it will putt on 1 cyl again. If you try priming the engine with propane (pushing primer button on regulator) it wont do anything until the excess propane clears out then it will putt on 1 cyl again.

Also, the timing whole is on the same side of the engine as the mag right? maybe that's my whole problem is that I'm not looking at the correct thing?

Any info would be much appreciated before I head out this weekend to work on it again! Please let me know if you guys need more info. I can get pictures and info this weekend if need be.

Thanks for taking the time to read my "novel" :)
 

nblack

Registered
Hi Waggy. (good moniker, BTW) OK. first, does your MAG "CLACK" when it turns over to crank the engine, or you turn it by hand? If not, If sounds like the impulser spring has broken (happens) and therefore the spark will be improperly timed to the position of the pistons in the cylinders. (If you attempted to time it correctly). What the impulser does is to fire the spark plug on the cylinder AFTER top dead center while the engine is cranking to ASSURE that the engine does not try to run backward and break your wrist whilst cranking.(assuming that you have one of the thousands of units that allowed for hand cranking) As soon as the engine fires and gets above a baseline RPM, (200ish) the impulser will lock out, and the timing will then advance to the proper advance for the engine, which should be 16' i think.
Second, Oil pressure sounds good. 20psi is perfect at operating temperature.
The way I time an L600/ L654.
1. find TDC on #1. Your Farmers trick is good. Fine tune it by using a thin screwdriver that tops out on the compression stroke for #1.
2, After verifying your MAG clacks, (and it is assembled correctly) check the FAQ at the top of this sub forum. (BTW, WhereTH is the OTHER helpful info that used to exist on the old site????????????????????)
3. Turn the MAG until it fires, and then turn it BACKWARDS until the points JUST START to open.
4. Mount the MAG in that finely adjusted postion.(may take a couple of attemps, as the gears are helical)
5. Put that wire (that just sparked) on #1.
6. Firing order is 1,3,4,2
Next,
We here are all old iron whores, and LOVE dirty pics. The more you post, The more we can help. Never mind the drool. It's normal.
best of luck.
Noel
 

Vanman

Subscriber
Last Subscription Date
07/10/2019
And one other thing that you should rule out is the possibility that it is getting too much fuel. Sure sounds like it.

Either adjust the mixture leaner, or shut off the propane altogether and try a little ether.

Does the carburetor have a choke? If so, it must be fixed wide open at all times for propane. If the choke were to be closed it would be getting WAY too much propane.

Keith
 

JeepWagoneer

Registered
Haha nblack, thank you for the well crafted reply. Yes the impulse coupling clacks but it seems (the more I remember it) I get a weak spark, I have a points and condenser kit I'll be installing into the MAG to see if that helps. I'll also be installing new plugs gaped to .018 (Service manual says that's the proper gap for propane) and new plug wires.. cap and rotor are pretty expensive so i'll only replace that if those turn up bad in our troubleshooting. Its a starter only unit (no hand crank) so as the starter is going I can hear the clacking of the mag until it fires in the 1 cyl then the engine speeds up passed 200 RPM and the clacking stops but the engine quickly goes back to under 200 RPM and the cycle repeats. It never seems to fire above 200 RPM.

As far as the timing instructions, I will follow those hopefully this weekend and let you know how I make out! As well as those pics you requested (this trip is a little up in the air but more than likely I'll be going)

Vanman, Thank you for the info. Admittedly, I never worked on anything using propane so I'm kinda feeling my way around the system. I did mess with where the propane line goes into the carburetor (long bolt with a nut on the end) I've adjusted it both ways and in either direction and once you get to far off in one direction it wont do anything when the engine turns over (leaner or richer) so my final adjustment is in a spot that has the engine trying to start most. Is there a proper baseline adjustment I can try? on some small Briggs it's something like 2 1/2 turns out after you screw the adjustment all the way in. I also have tried no propane and just either.. no juice. :( Just putts occasionally until there is too much starter fluid. And yes the carb has a choke, it's electric though so I just kind of assume its doing its thing (I will check.) It has two wires connected to it, what controls it?

Thanks again guys for the helpful replies!
 

jack0

Registered
Age
60
Haha nblack, thank you for the well crafted reply. Yes the impulse coupling clacks but it seems (the more I remember it) I get a weak spark, I have a points and condenser kit I'll be installing into the MAG to see if that helps. I'll also be installing new plugs gaped to .018 (Service manual says that's the proper gap for propane) and new plug wires.. cap and rotor are pretty expensive so i'll only replace that if those turn up bad in our troubleshooting. Its a starter only unit (no hand crank) so as the starter is going I can hear the clacking of the mag until it fires in the 1 cyl then the engine speeds up passed 200 RPM and the clacking stops but the engine quickly goes back to under 200 RPM and the cycle repeats. It never seems to fire above 200 RPM.

As far as the timing instructions, I will follow those hopefully this weekend and let you know how I make out! As well as those pics you requested (this trip is a little up in the air but more than likely I'll be going)

Vanman, Thank you for the info. Admittedly, I never worked on anything using propane so I'm kinda feeling my way around the system. I did mess with where the propane line goes into the carburetor (long bolt with a nut on the end) I've adjusted it both ways and in either direction and once you get to far off in one direction it wont do anything when the engine turns over (leaner or richer) so my final adjustment is in a spot that has the engine trying to start most. Is there a proper baseline adjustment I can try? on some small Briggs it's something like 2 1/2 turns out after you screw the adjustment all the way in. I also have tried no propane and just either.. no juice. :( Just putts occasionally until there is too much starter fluid. And yes the carb has a choke, it's electric though so I just kind of assume its doing its thing (I will check.) It has two wires connected to it, what controls it?

Thanks again guys for the helpful replies!
If you think you have weak spark, you most likely do. Any idea when the unit was last run? I would start with the simple things, like checking the points. They're most likely pretty crusty. You could just dress them and see if it will run. If your going to replace them, I find it easier to remove the mag from the engine. Put a reference mark on the flange for reassembly and proper rotor orientation at tdc comp.

If your L654 is anything like mine, the chokes aren't that great. The heater coil is only energized until the generator has output, by then manifold vacuum has already pulled it open. Not the best design if your running on gasoline in a cold environment. Mine was touchy till I found the right spot.


Looking forward to some pics.
Good luck. These are nice running engines.
 

Vanman

Subscriber
Last Subscription Date
07/10/2019
Yep, and check / replace the condenser. I was running my L600 during a scheduled power disruption, when it suddenly sounded terrible and began to loose speed. I chased carburetor problems for quite a while, but it just kept getting worse. Finally basically wouldn’t run at all, much like yours, and I brought in another set. The condenser tested good on a multimeter, but I tried a new one for the heck of it. And away she went! Never had a carburetor problem to begin with.

“99% of carburetor trouble is ignition related”. ;)

Keith
 
[QUOTE="Vanman, post: ]
.“99% of carburetor trouble is ignition related”. ;)

Keith

Oh, so true. From one of my old engine books "The spark should be 'fat' and bright blue. If it is white and spindly, suspect the ignition condenser".
 

dkamp

eMail NOT Working
Yep, the impuler should be loud, the spark should be strong... here's the proper test:

Pull one of the plug wires out of the mag towers, Place your first finger over the hole. turn the motor over slowly with your other hand. After the 4th click, if you're incontenent on both continents, and emptied the encyclopedia of all languages of profanity, you're good.

Really, it needs a mean, loud snappy spark. You'll probably find that after replacing the points and condenser, that it'll be a whole lot better, but my preferred handling is to carefully remove the mag, and take it to the local 'magneto guy' to have it completely rehab'd and set up, and after that, keep it dry and regularly exercised. The magneto is a slick gadget, but to work properly, there's several things that really need to be set up right, and one of them is 'phasing'... meaning, the points need to open at just the RIGHT time in the rotation angle of the magneto's armature. You can have the gap right, and not have it properly phased... and you can have it phased right, not the wrong gap... and you'll have flaccid spark in both cases.

As for the propane mixing system... locate ALL the adjustment points, properly identify them, and then religiously LEAVE THEM ALONE...

It's not a gasoline engine... propane is a totally different system, and after you study them, you'll realize just how incredible they are.

Propane starts out as a liquid, entrapped in a can, under pressure... depending on ambient temp, that pressure could be as high as 210psi or so, all the way down to ... nothing at all. Your engine does not burn LIQUID propane... it may be set up for liquid withdrawl, but it will not BURN it (liquid will not burn, because it cannot mix with oxygen!). This is like gasoline, except... that gasoline engines spit lots of unburned fuel out the pipe because it never fully evaporates.

That big bolt you found, is probably the LOAD VALVE. It controls NOTHING... at least... until your generator is alive and running at WFO... full load... max. If that throttle plate is anywhere other than WFO, the load valve is NOT involved. It's job is strictly to serve as a limit for maximum fuel flow, and nothing else.

Your generator's mixer MIGHT have a 'minimum fuel mixture' orfice. Some do, most don't, and it's basically irrelevant on a 60hz generator. It MAY have an 'idle screw'... but on the generator, the idle screw's ONLY purpose is to provide some method of preventing the throttle plate from being jammed shut if the event that the throttle closes for some reason (but they basically never do).

The MIXTURE that your generator is processing, is metered by one wonderful, dandy little gadget called either a Fuel Controller, or a Demand Regulator, a Zero Governor, or a Negative Pressure Regulator. Same dude, three names, it's simply an baromechanical analog fuel injection control unit. Fuel comes in at a high pressure, and it is 'metered out' based on demand.

At ANY given engine speed and load, there will be a certain amount of engine fuel/air demand, and this air, flowing through a fixed venturi, will develop an atmospheric pressure differential between the venturi bore, and the outside air. The fuel controller manages this with a large diaphram and a spring.... and NONE of it is in the combustion airflow- it's strictly in the fuel path, which by the way... is a WHOLE LOT cleaner than the stuff you're pulling out of a car gasoline tank. Propane is handled in a totally sealed environment, and it does NOT degrade.

Fuel is introduced into the mixer's venturi through plumbing (which includes the 'load valve') and because of the pressure differential, fuel is 'sipped' by the venturi. The Fuel Controller's diaphram has a large acting surface, and a spring. The spring shuts off fuel, but if the atmospheric pressure on one side is HIGHER than the INTAKE, the diaphram deflects, allowing propane to enter into the cavity of the fuel controller's vacuum side, thus, drawing it into the engine.

Imagine an ordinary air regulator... it's set to 95psi... if the pressure in your hose is only 60, the regulator opens to flow in more air...

And it's ALL about proportion... and because that valve is mechanical, it wears. Over time, the diaphram hardens, and a spot is worn in the valve, a little dirt and corrosion, resulting it to be 'catchy' at that point... and it doesn't meter well. When this happens, you have two choices- rebuild, or replace the valve. They're SO safety-dependant, that most of the valve you go looking for... will be priced so that a rebuild kit, or a replacement valve... is about the same price. Don't waste thought on doing a rebuild.

Propane engines don't run like gasoline. If you're a gas-engine gearhead, throw away what you know about engines. Most accurate advice I ever got- If the propane engine sounds like it's running 'lean', it's actually running rich. If it sounds like it's running RICH, then it's running lean.

Did I mention that you need a REALLY REALLY REALLY hot spark? Yeah... incontinence on both continents.
 

JeepWagoneer

Registered
Oh man, all kinds of excellent info! Okay, let me start my update with pictures! I know everyone wants to see it so here it is, the 1984 Hesco Mobile Power Unit!
IMG_1365.JPGIMG_1366.JPGIMG_1368.JPGIMG_1372.JPGIMG_1374.JPG

So with this last pic... Is this the timing hole? Under the starter solenoid? Also does anyone know what red cylinder is to the bottom left of that same pic?


A little back story on this former Verizon owned unit. I bought it around August of last year from a liquidator in Maryland sight unseen, I was feeling gamblie.. Really I was looking for a fun project. I found out pretty quickly that it didn't run and seemed like a timing issue but my little knowledge with Mags at the time stopped me in my tracks and as the winter came it really curbed my enthusiasm. I did notice a couple of interesting things at the time that helped me diagnose timing issues other than the putting. On the air pressure tank for the compressor system it had the firing order written on it in marker. The mag got similar marker treatment... what plug wires went to what cylinder where written on it. The final nail in the timing coffin was that someone took off the large plastic cover for the mag that covers the points and must have wrecked the gasket because it was RTV'd back in place. You could pretty much smell the anger and frustration that some poor guy had working on it before he decided to throw in the towel and sell it (at least he put it back in one piece. :) oh also I do have a new gasket set for the mag!) Not much has happened in the months that followed so that pretty much brings us to now and the adventures of today!

I drove down with the plan of installing new points, condenser, felt wick, gaskets and installing it back into the engine with the correct timing to hear it run. But plans changed so I ended up bringing the mag home with me to work on it. After a lot of feeling my way through points ignition (repeated trial and error) I managed to get the mag all back together with a HEALTHY and FAT blue spark and a nice loud clack to boot! You could practically hear the thunder coming off that baby! So that makes tomorrow and installation and timing day. Hopefully that solves everything, I will report back tomorrow, Let me know if you guys need more pics of anything specific.

Final adjustments are:
.015" gap for points (highest point of cam)
.018" gap for spark plugs

Thank you Jack0, Keith, George Andreasen, and dkamp for the spark tips! And dkamp again for that very in depth guide into propane, lots of useful info there! I will take special care to "locate ALL the adjustment points, properly identify them, and then religiously LEAVE THEM ALONE..." 😁
 

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dkamp

eMail NOT Working
Wow- that's a NICE unit! If anyone comes across another complete HESCO, I could really use one (really... )

Okay, so two other notes:

Magneto- NEVER use resistor plugs or wires. Solid core only!

Kohler four cyl engines... #1 is end OPPOSITE the fan... it's the cylinder closest to the gennie...

The red thing down at the bottom... does it have a flat AC cord coming out of it? Perhaps two water lines? If so, it's an electric block heater... your HESCO probably has that, and a float charger on it, so that (at the shop) it'd be parked and plugged in, so that when it got called-to-duty, they could hitch up and unplug, head out, and it'd fire right off.
 

Vanman

Subscriber
Last Subscription Date
07/10/2019
Dave, we should start a thread dedicated to the use of resistor plugs and wires with magnetos. ;)

Keith
 

JeepWagoneer

Registered
Hey guys, I was out there today working in it and to my surprise it started right up! Okay it wasn't that easy but here's the scoop.

Oh and a link for anyone that's interested in the unit running thanks to all your help!
(Yes that genuine excitement you hear :))

first thing I did was time the engine to nblacks specifications, but I was having a lot of trouble for some reason. It sounded like it was way to late again. I noticed a timing mark on the rotor and decided to click the mag until it reached number 1 on the distributor cap then reversed direction until that timing mark was back in the window. Now with the engine back in TDC on cylinder number 1 (oh I figured out that it was actually the orange mark on the flywheel) I installed it with the mag straight up and down and reconnected the spark plugs (I had cracked one of my spark plugs by this point and was getting a little frustrated, I pushed on and reused one of the old plugs) Now at this point I was not ready for how easy this engine started up.. as you'll see it really just started right up! After sitting for who knows how long before I got it and then 7 months since I've owed it. it was also around 45-50F so slightly chilly though warm for this time of year in Massachusetts but there it was! Running!

So now I had it running but no way to test the genny out. I couldn't believe I didn't bring anything to load it up! Until I realized that this thing is chock full of goodies to try out! First I tested the Blower motor on low and high, that worked. Then the super heater and receptacles and those worked too! Unfortunately one of the compressors sounds bad and the other one wont turn on. The dryer switch (no idea what that controls) was making a grinding sound when I turned it on so that's no good. The water pump that was built into the trailer also wouldn't tun on but I imagine its because I didn't have the control switch flipped to manual.. silly me. I'll check that out next time I'm out there.

With the good and the bad out of the way I decide to leave the blower motor on high with the heat all the way on and the super heater on. (Not really sure how the super heater works.. I think it creates a dummy load on the generator to cause the engine to work harder that in turn makes the coolant hotter and makes the heat for the blower hotter.. it pulls 20 amps alone!) With this combination I was able to put a 3500 Watt load on the generator and I let it run for a 1/2 an hour like that. I kept an eye on it to make sure it wasn't gonna over heat or run poorly as it warmed up and honestly it just kept humming away without any drama. Once it warmed up the oil pressure gauge read 30 PSI which I imagine is more like 20 as the gauge rests at 10 when its off.. and that's that!

Next on my list is getting proper propane tanks for it.. anyone know what these units take? I was thinking 2 100lbs tanks but not sure whats supposed to go there. As well as an oil change. It looks brand new but its been in there for a long time so I think i'll replace it and just keep up with a regular interval from there on out.

dkamp, You were absolutly right about that red cylinder being a block heater.. There is a coolant line that runs from the head of the generator to it (In my last post with pictures you can see a rusty pipe coming off of the cylinder head just to the right of the "Oil Fill" tube and to the left of the oil filter that runs to the other side of the block heater)

Another question for anyone who happens to know. Hesco operating manuals.. they seem to not exist does anyone know where to find them? I'm dying to know how the "Remote Pump" receptacle works.

IMG_1371.JPG

I've seen one used on youtube for a newer generator and it turned out that the pump had a float on it that could start the generator when the water level was too high, then once the level went down it would shut the generator off. Like a giant sump pump. I wouldn't use it for that, I would probably try to find out how I could make it remote start using that port... just a thought anyway.

Final thoughts let me know how you guys think its running. all I had with me was my tools and a copy of the Service manual for this generator (which oddly enough said that the #1 cylinder is at the radiator) so I hooked up the spark plug wires that way and don't seem to notice anything wrong. Not bad for a machine that's just shy of 5,000 hours of operation! Not even burning oil!

And with that, I thank you all for your help! You guys helped give another l654 a second life! 😊
 

Vanman

Subscriber
Last Subscription Date
07/10/2019
Awesome! (y)

On an in-line four, either end may be designed as number one and it will not make a difference. :brows:

Keith
 

dkamp

eMail NOT Working
Heh... as long as it's a 'wasted spark' system, Keith... if not, and you're switching 1 with 4, and 3 with 2... it'll be rather unhappy. Had a guy do that with an Allis B once, it really left him baffled... turn the crank, and it belched fire out the intake each time :jester:

And JW- you hit the nail on the head... the 'remote pump' connection is for a switch that self-starts the unit to power the pump when water level is tripped.

A pair of 100lb'ers and a Y-pipe 'tween 'em would be a good choice. Your single 20 will chill rather fast, and leave your tanks frosty and vapor sluggish on even very warm days. I saw a HESCO up in northern Wisconsin some years ago, they'd piped the exhaust out with a directing elbow onto the twin 100's, and I'm pretty certain they did that to make sure it'd stay happy on a -25f day.

Ain't it a sweet running little motor? ;-) I'm happy you got her woke up!

Now, if you live in a rural-ish area, and have a big farm tank, put an appropriate disconnect fitting on the vapor tap of your big tank, and make a jumper hose that'll connect to your HESCO. Pull a wire from an interlock backfeed breaker your house panel to connect to your HESCO, and include a control connector to the remote pump" control, with a switch by your house panel to control the HESCO, and a 20A receptacle to plug in your HESCO's engine heater/charger. Put a temperature switch and control relay on the HESCO (so the engine heater is disabled above say... 35F) and a timer on the charger (so it only runs an hour a day or so), and when you're not using it on a job somewhere, you'll have it ready as a standby backup generator!
 
Last edited:

Vanman

Subscriber
Last Subscription Date
07/10/2019
Dave, if you follow the firing order, the sequence is the same, regardless of which end you start with. At least for a 180* crank. I haven’t thought about it for one of those weird engines with a 90* crank.

Good advice on the backup setup. (y)

Keith
 

dkamp

eMail NOT Working
Okay, so after Nole chewed my ear for a few minutes (yes, I had a mask on), he's clarified that the GEN end on the L600 is #4. He confirmed that L654 is same- they started from the cooling fan end. I stand corrected on the enumeration there.

Which kinda surprises me... on the Waukesha-powered machines, they started from the rear.

MY point is, that if you have it set up and timed and running, and arbitrarily swapped wire 1 with 4, and 2 with 3, it will NOT run.

If you follow the setup procedure, and use the procedure from the git-go, it won't matter, as long as you set the mag and pick the end in the SAME way.
 

Vanman

Subscriber
Last Subscription Date
07/10/2019
Ahh, I see where we were not quite on the same page. Indeed if you merely swapped the wires around then it would not work as the mag would be 180* out. But no matter which end you designate as #1, and set the engine to TDC compression on that cylinder, and the mag timed to fire that plug at the same time, then it will work from either end.

The inline four firing order is always symmetrical. Either inner cylinder to outer, then the other inner to the other outer, or vice versa depending on whether it is 1342 or 1243.

BTW I discovered this accidentally when working on one of the early overhead valve Kohlers. The firing order is cast into the rocker cover, but #1 is not marked on the engine. I checked it both ways, using my thumb over the plug holes, and well, there you have it. :brows:

Keith
 

JeepWagoneer

Registered
Dkamp, Excellent idea on the setup for standby power! I'll have to come up with a clever adaptation for when I move. Any idea how that plug is wired? (I imagine 1 is hot, 1 is neutral/signal/volt sensing?.. and a ground) Just trying to see a way I can jump the connectors in the plug to test the auto start system.

For anyone else that's trying to follow along with this thread for their own timing troubleshooting adventure, I figure its only appropriate to summarize my solution.

On my l654, the timing marks weren't labeled with the "S" and "T/M" marks that others have noted on other threads. Instead my example has Orange and white marks. (I don't know if it came from the factory like this or it was someone getting crazy with a paint marker) If yours is like this, this is what mine was:

Orange: Cyl 1 is at top dead center (TDC) (Its possible its on TDC for compression or in between exhaust/Intake strokes, take care to know what stroke the piston is on.
White: Not exactly sure on this but my guess is this is the mark for 16 degrees before TDC. so with the engine running you can adjust the magneto to get that mark in the center of the timing hole for optimal engine performance.

Feel free to correct me on that guys, I may be way off on the white mark.

I had rebuilt the points part of the ignition system. New condenser, Points and felt wick came with my kit (found it on ebay) as well as new gaskets all the way back to mounting the mag (Magneto) onto the flange on the block. I also bought new plugs and wires

Here are the final adjustments I made to my engine:
Points gaped at: .015"
Spark Plugs gaped at: .018"

Note: The .018" spark plug gap is for Propane and .025 is for Gasoline.

And there we have it, a timed l654 (and in my case a running one that didn't misfire once the whole 40 min test run and load. It was really quite an amazing sight!) . I think that sums up my adventure and hopefully will help anyone following along on this post.

Thanks again everyone!

Dkamp, I look forward to your reply 😜
 

dkamp

eMail NOT Working
Dunno, JW... but if I had the panel off, or was lookin' at the back of it, and could trace some wires, I'll bet I could figure out fairly quick... any way you could get in there for a little exploratory investigation?

So... timing a magneto, particularly one with an impulser coupling, is a little different from say... a distributor with mechanical and/or vacuum/electronic advance.

The impulser coupling's trip point is more than just something that makes it whip around quick for a hot spark. It's an ignition retard.

In my 'universal' instruction, you'll see that I mentioned pulling it slowly past TDC, and waiting for the CLACK.

When running slow, the impulser ALWAYS fires the cylinder AFTER TDC... that's to prevent kick-back. Once you get up to high enough speed to centrifugally-disengage the pawl-weights of the impulser, it runs in direct-acting state, which is inherently EARLIER than when below impulse.

The impulser, therefore, has integral advance by nature of the 'fixed' angle of impulser's pawl engagement geometry.

And the short/sweet of it, is that if you adjust the impulse release point so that it's just a few degrees past TDC, it will inherently be advanced the proper distance.

As far as the colors are concerned, if it were Orange and Green, I'd venture that The Troubles of Ireland had carried over to your flywheel. On my Allis B, the hard-to-see notch carved in the flywheel is painted white... because I happened to have a white paint pen at the very moment I finally found that @#$!^%R after crawling in and out from under it eleventeen dozen times.

Don't they run nice? Yeah, and when guys have little flatheads that DON'T run nice, I always do the same routine- drain the pan and coolant, pull the intake/exhaust, cyl head, clean out all the passages, scrape the piston tops and gasket surfaces clean, pull the side cover, release all the valve springs, lift out and wire brush each valve, carve out all the crud in the ports, carefully, gently run a cleaning ream through the valve guides, drop the valves back in, give them a visit with the lapping-stick, then clean everything up nice, check the valve spring pressures, set valve clearance, and put it all back together... for any head bolts that protrude into coolant passages, I lube the threads with Teflon pipe compound, new gaskets, new manifold studs (if they're eroded), clean and inspect the manifolds (especially where intake and exhaust meet... look for cracks!), and then retorque, and fire it up. MOST of the time, if it's a flathead, and it's grumpy, the CLEANING OUT is what it needs first and foremost.
 

nblack

Registered
OK, my instructions were general instructions based on no knowledge of your particular Magneto, or choosing a specific High Tension tower on your Mag. Kohler used at least a couple of different Mags on these units. One (the one you had) has a window that is often blocked with age and fog. The other has no window at all. Any tower will work as #1 with my instructions. The other assumption that I made with my information was that your Mag was internally timed correctly. (ref DKamps phasing comments) Glad you got your unit hummin'! These are venerable units. Also, with reference to the paint marks as opposed to the SPK, It seems like I have seen this before on other units. It still shows up with a timing light... ;)
 
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