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Yet Another Webster Begins

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awake

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Bob, at the risk of telling you things you already know ...

The touchiness of the throttle may be due to either / both the mixture setting and the spark timing. Get the engine running, then experiment with the mixture. You'll pretty quickly get a feel for the range in which it runs best. (Note that it will want to be richer when cold, leaner as it warms up.)

As for spark advance, I don't recall if you included any adjustment. I would say that this makes less difference on my Webster than I expected, but in general the closer the timing is to TDC, the easier it will start, but the less well it will accelerate or run at higher speeds. Advancing the timing too far can lead to the opposite - hard to start, but eager to run at higher speeds. Again, with the engine running, adjust the advance (if it is adjustable) until you find a happy medium.
 

CFLBob

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Werowance,

Does this help?

TestOverview1.jpg


The spark plug wire came with the electronic ignition from Roy Scholl at Roy's CDI Ignition Systems I'm not sure what gauge wire that is but it's a thick insulation and the cap on the plug is softer than I remember those being on any car I've ever worked on. The thin black wire is the ground, and it goes to a screw I added in the cylinder head when I was wiring it up.

The black module is the electronic ignition, the white wire going under the fuel tank holder is the points contact to that. The battery pack that runs it is at the top. The green wire jumpers out one battery in a holder that I had lying around that holds 4 AA batteries, so it turns a four cell holder into a three cell.
 

Steamchick

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Hi Werowance. Just a couple of comments about HT cable. As the spark energy is high frequency, it is susceptible to the impedance of the circuit, including the spark plug. Manufacturers of systems optimise the system usually by using the optimum HTC cable resistance, capacitance and inductance (combined as impedance) different diameter and insulation designs are of different capacitances, and different 'wires' can be of varied resistances and inductances. . .. So you need the correct HTC cable as specified by the system manufacturer for best performance. Of course, often you can 'manage' with a different design of cable, but it risks higher voltages appearing inside the 'spark generator' (coil, capacitor, trick box, etc.). The wrong cable can mean poor sparks at full throttle - when the spark has the highest resistance to break-down the gases in the combustion chamber and generate the spark.
Take care,
K2
 

werowance

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Thanks, I'm just using a car plug wire for a ford coil. I think I asked for a 1976 Lincoln continental coil wire. and just a regular old ford coil driving it. it works fine on mine but was curious if there wasn't something a little nicer for a model engine is all.

the Lincoln is the model my parents had when I was a little kid. I stayed car sick and I called it the vomit comet as I got sick everytime I got in that thing. had that strong smell of leather, was dark blue almost black, and the ride was In all different directions. the car didn't just spring up and down but seemed to "float" in all axis's all of which just made me sick as could be...... but that's another story I guess.
 

ZebDog

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congratulations sir on getting your Webster engine running.
I had the same problem with the head rocking back and fourth I fixed it by putting two extra 4mm screws in the bottom, it worked for me.
 

Steamchick

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Thanks, I'm just using a car plug wire for a ford coil. I think I asked for a 1976 Lincoln continental coil wire. and just a regular old ford coil driving it. it works fine on mine but was curious if there wasn't something a little nicer for a model engine is all.
Hi Werowance: On ignition systems: Ford and "the rest" had different strategies for coils - from what I learned in the UK "as a lad".
Most 12V cars (in the world) used 12V coils. But back in the days of yore - when battery electric systems were first designed to replace magnetos - the Batteries had times when they were at very low voltage when cranking - so the sparks were weak and with an aged battery customers complained of poor starting. Ford decided to overcome this by using a 6V coil + Ballast resistor, which allowed the coil to run safely on the 12V system. When the starter button was pressed, the feed to the starter solenoid also fed the coil - thus by passing the ballast resistor and allowing "full battery voltage during cranking" to provide the sparks. As the batteries typically dropped to between 9V and 6V during engine cranking, the customer got really good sparks and a much more reliable starting system. I think this allowed Ford to use slightly smaller batteries and the cost saving off-set the cost of the extra wire and ballast resistor. I think many Fords had this certainly up to the 1970s, and really no reason to change until coil-on-plug became the way to go. I don't know if any other manufacturer used this arrangement? - So is your Ford coil a 6V job?
As an alternative, for a small 6V coil for your next engine, you could research using a Honda step-through (50cc to 90cc motorcycle) coil, or something similar? - e#@y has stuff for around $20 from China, complete with HT cable and regular automotive plug-cap. e.g. 6V Ignition Coil with Cap For Honda CB100 CL100 SL100 XL100 CB125S CL125S SL125 . Then all you need is the contact breaker, condenser and 6V battery? May be cheaper than Roy's CDi stuff, but his will be good and reliable if you don't want to assemble your own "old fashioned" coil system?
Enjoy!
K2
 

CFLBob

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After a dab of green LocTite (680) and letting it cure overnight, I sat down to start the engine, with the idea of letting it run once a day for a while. It simply would not start. While figuring out what was wrong, I tried tightening the screws to reduce the wobble as the piston moved, but they were already tight. I found the batteries in my electronic ignition needed to be replaced, and the lower level of fuel in the tank made positioning it difficult. It eventually did turn over a few times, but wouldn't keep running. The vibration was so bad that the carburetor throttle lever would bounce out of the range it works over.

Last week @Steamchick had mentioned a triangular brace on the other side of the head, so I started thinking about that. The first thing I did was pull the drawings back up - this is on sheet 4 of Webster's plans. He left out all hidden lines on the head "for clarity" (a note in the top left). I started adding the hidden lines so I could see where everything was. The top of the head is probably the best place to put a reinforcement, since the force from piston pushing on the head produces the most torque farthest from the base, but there's no more than 1/4" of wall up there to drill and tap without breaching the combustion chamber.

I eventually added two #8-32 screws in the base, on the opposite side of the 6-32 screws that hold it to the side frame. Adding in the hidden lines allowed me to see the screws coming in from that side would hit the #10 screw that holds it to the base. I displaced them "forward" (farther from the flywheel), which looks to the right in the view on the plans. So I redrew the head from the other side (where the cylinder used to be) to show the way they look from the side looking at the engine. This screen capture off my computer should help show it. Dimensions in black are all mine, the bottom half is all mine, the notes in black are mine.

HeadBracketMod.jpg


The bottom half shows the bracket that would be flush with the front of the head, adds two screws on the left, 0.160 from the end, and two screws in the bottom. The head is shown with bracket copied onto it on the right.

A little search around the shop led me to a piece of scrap the same thickness as the side frame (5/16" or 0.313"). Coincidentally, almost exactly the distance from the edge of the head to the edge of the base plate. The scrap had an odd shape, but I just needed to trim and square it up a little to have something usable. A second search led me to find exactly two screws for each of the two places. That meant I had what I needed to clean up the scrap and make a brace. I spent some time trying to figure out how to do this without disassembling the entire engine. I figured I'd clamp that bracket to the head and use it as a guide to drill and tap the new #8 holes. Once the holes were in the side of the head, I could pull the bracket off, move the engine over to the CNC mill, zero on the vertical line where the new screw holes are, use the 1.586" calculated distance from there to the first, new vertical hole, and drill through the base plate.

It actually all went together easily. Pay no attention to the fact that the two 8-32 screws on the side holding the new bracket don't match. One isn't stainless. That's just cosmetic.

Mod_Completed.jpg


By the time I finished this, I had used up the afternoon, so I don't even know if it works yet. I think that curved surface on the top of that bracket or brace or whatever you call it needs some more finish work
 

Steamchick

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Thanks Bob! I'm humbled that you have followed my advice. Looks much better now (to me). Hope it fixes the wobble?
K2
 

Brian Rupnow

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Bob--you may have missed it on the plans, but there should be two #6-32 flat head bolts positioned directly across from the new bolts you put in which hold the long crankshaft support plate against the side of the cylinder head plate. There is also one bolt up from underneath the base which threads into the bottom of the cylinder head plate.--EDIT---I have just looked back to the beginnings of this thread and seen that you have the holes in the appropriate places. If these bolts are in place and tightened, there is no way the cylinder head should have been wobbling around like it was in the video.-Brian
 
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CFLBob

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If these bolts are in place and tightened, there is no way the cylinder head should have been wobbling around like it was in the video.-Brian
All three are in place and I can't tighten them any more. Any ideas what I could look for?

Pretty much the only thing I can think of is that the screws are bottomed out early - too long - so that the screw won't go in any further, but don't bear enough load onto the base and side frame. That doesn't seem to be the case.
 

Brian Rupnow

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Check the screws for bottoming out. If they are doing their job, there is no way that plate can wiggle around.---Brian
 

werowance

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Hi Werowance: On ignition systems: Ford and "the rest" had different strategies for coils - from what I learned in the UK "as a lad".
Most 12V cars (in the world) used 12V coils. But back in the days of yore - when battery electric systems were first designed to replace magnetos - the Batteries had times when they were at very low voltage when cranking - so the sparks were weak and with an aged battery customers complained of poor starting. Ford decided to overcome this by using a 6V coil + Ballast resistor, which allowed the coil to run safely on the 12V system. When the starter button was pressed, the feed to the starter solenoid also fed the coil - thus by passing the ballast resistor and allowing "full battery voltage during cranking" to provide the sparks. As the batteries typically dropped to between 9V and 6V during engine cranking, the customer got really good sparks and a much more reliable starting system. I think this allowed Ford to use slightly smaller batteries and the cost saving off-set the cost of the extra wire and ballast resistor. I think many Fords had this certainly up to the 1970s, and really no reason to change until coil-on-plug became the way to go. I don't know if any other manufacturer used this arrangement? - So is your Ford coil a 6V job?
As an alternative, for a small 6V coil for your next engine, you could research using a Honda step-through (50cc to 90cc motorcycle) coil, or something similar? - e#@y has stuff for around $20 from China, complete with HT cable and regular automotive plug-cap. e.g. 6V Ignition Coil with Cap For Honda CB100 CL100 SL100 XL100 CB125S CL125S SL125 . Then all you need is the contact breaker, condenser and 6V battery? May be cheaper than Roy's CDi stuff, but his will be good and reliable if you don't want to assemble your own "old fashioned" coil system?
Enjoy!
K2
Hi Steam chick, mine is a off the shelf ford Lincoln continental coil. i made a coil kit in a box that i can move to my other engines. there is an external ballast resister on it. it runs on 12 v. i make my engines with quick connects to the points setup and then the spark plug wire to the plug. i use a 12 v gell cell alarm battery to power it with all held together inside a converted ammo can.

i use this same setup on old 6 v tractors when i convert them to 12 v for example a few farmalls i have done. delco 4si alternator and the coil / ballast resister. honestly the 6v coils work fine with 12 v on the farmalls but they are usually in such bad shape when i see them full of white corosion or the the metal case rusting through that i change them out.

all that said, i just thought Bobs plug wire looked neat and nice and wondered where he found a coil wire that small. my full size one works great and is only connected when running them.
 

CFLBob

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Short version of the story is this seems to make all the difference in the world. Steady as can be. Unfortunately the engine is still being a pain about not starting reliably.

While I was troubleshooting, I noticed the red LED on the ignition would show the spark going off when the cam wasn't in the right position, and then not sparking when it was supposed to. My points have crapped out. I mentioned before that they would stop moving and wouldn't work until I oiled them. That isn't working today. It has been since the early 80s that I worked on an engine with mechanical points and I never oiled points.

I think it's time to get some new ones. These were from NAPA. Based on these, I wouldn't go back for another set.
 

awake

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Bob, for no particular reason other than easy availability, I used a points set for older Ford tractors - readily available for not much money on Amazon, but also through places like Tractor Supply. I have no idea if this was the best choice, but it has certainly worked reliably for me on my Webster.
 

Brian Rupnow

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Bob--If you are holding those points in place with a #10 bolt, they won't operate freely. Run a 3/16" drill thru the points mounting hole and then put a dab of Loctite on the bolt threads and don't tighten it down--just run it into the threaded material until the underside of the head just barely touches the points, so that the points are free to rotate. You should be using a #6 pan head bolt thru the slotted hole in the points, and it should be snugged down to set the points gap.
 

CFLBob

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Bob, for no particular reason other than easy availability, I used a points set for older Ford tractors - readily available for not much money on Amazon, but also through places like Tractor Supply. I have no idea if this was the best choice, but it has certainly worked reliably for me on my Webster.
Andy, I recall your post about the Ford tractor points from a couple of pages ago when I was first posting about some issues. Someone else posted about these CH14VT points and they got a set for a couple of bucks. I ordered these yesterday:
Just because they were about $5 less, including shipping, than the Ford tractor points on Amazon.

Bob--If you are holding those points in place with a #10 bolt, they won't operate freely. Run a 3/16" drill thru the points mounting hole and then put a dab of Loctite on the bolt threads and don't tighten it down--just run it into the threaded material until the underside of the head just barely touches the points, so that the points are free to rotate. You should be using a #6 pan head bolt thru the slotted hole in the points, and it should be snugged down to set the points gap.
When I was building the support where the points are mounted, I made the mistake of making both holes 10-32 instead of 8# on the left and #10 on the right, like Webster drew it. I've used a #10 pan head screw on the slotted hole, and needed to widen the slot with a needle file. On the #10 side, I drilled out the hole, but I don't recall if it was a full 3/16 or slightly smaller.

The points seem to have been ruined, so I need to approach this more carefully when the new ones get here. Right now, if I squeeze the points to open them, they won't spring back to closed. They just sit there open. If anything, I'll drill out the points with something bigger than 3/16. If it looks like the metal can bear it. The drill size chart I have for tapping holes says a "Free Fit" for a hole to pass through to get to a tapped #10 hole is 0.201 and close fit is 0.196. 3/16 is quite a bit smaller than the close clearance number they give.
 

Brian Rupnow

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Bob--Pick up a #10 bolt and measure it across the threads with a vernier. They measure 0.188" diameter. A 3/16" drill will always make a hole about .0005" over. You won't end up with a lot of clearance, but there will be enough to let the points rotate freely.
 

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