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LarryF
08-26-2010, 11:19 PM
It's a 10HP B&S
Model 243432
Type 0732-01
Code 7908281

Problem is no spark. Plug, points and condenser seem to be ok, and I didn't see any wire breaks in the vicinity of the coil when I removed the recoil starter assembly. I set the points at 0.020", but I don't see any sparks when I pull the starter cable. I'm thinking it might be the coil, but I don't have the engine parts manual and can't find any reference to it on the web, so I don't know which coil to order.

Can anyone help or perhaps suggest what else might be the problem?

Restrorob
08-26-2010, 11:51 PM
Larry,

Just purchase part #398811 electronic ignition coil and be done with it, Just cut the wire coming out of the points cover and leave the points/condenser in place. The new coil should come with a new kill lead wire in the box.

LarryF
08-27-2010, 08:51 AM
Larry,

Just purchase part #398811 electronic ignition coil and be done with it, Just cut the wire coming out of the points cover and leave the points/condenser in place. The new coil should come with a new kill lead wire in the box.

Thanks! That's much appreciated. I'm so out of touch with this that I wasn't even aware this could be done. When I Googled that number, I saw a lot of places that can provide it but no explanation of how to go about making the replacement. Do I just remove the recoil starter assembly and take out the old coil and make a swap? Is there a web site showing what to do?

LarryF
08-27-2010, 11:00 AM
While waiting to hear from someone who might provide instructions for making the replacement, I did some searching on my own and while in the process, stumbled upon the Outdoor Distributors web site that provides the owners manuals for almost all B&S engines, including the one I didn't have. In case anyone is interested, this is the site:

http://www.outdoordistributors.com/briggs_and_stratton/briggs_part_lists.html

and if you go to their home page, there are similar manuals for many other engines and lawn-equipment.

But I still didn't find what I had been looking for, so if anyone can provide the procedure for replacing a point-condenser-coil system with a 398811, I'd like to see it before ordering that electronic coil system.

LarryF
08-27-2010, 11:39 AM
This must be the one you recommended, Restrorob. But maybe not since I don't see a kill lead in the photo. Looks like there are a lot of after-market substitutes for the 398811, so maybe one of them had the kill lead.

Restrorob
08-27-2010, 01:13 PM
Do I just remove the recoil starter assembly and take out the old coil and make a swap?

Yes,

The black rolled up wire in the lower left is the new kill wire lead, One end plugs onto the new coil the other end with the gold wire connector goes to the screw post on the throttle control assembly.

All you have to do is remove the old coil and install the new, Use any business card between the new coil and flywheel to set proper air gap. To save having to remove the flywheel just cut the points wire as close to the flywheel as you can and let it be, If you do it this way you wont need the rest of the parts in the above pic. Just the coil and kill lead.....

LarryF
08-27-2010, 02:03 PM
Yes,

The black rolled up wire in the lower left is the new kill wire lead, One end plugs onto the new coil the other end with the gold wire connector goes to the screw post on the throttle control assembly.

All you have to do is remove the old coil and install the new, Use any business card between the new coil and flywheel to set proper air gap. To save having to remove the flywheel just cut the points wire as close to the flywheel as you can and let it be, If you do it this way you wont need the rest of the parts in the above pic. Just the coil and kill lead.....

Thanks again! OK, it's now been ordered. The place I'm getting it from volunteered an alternate to the B&S product for 10 bucks less, but I declined since I'm not too sure a bad coil is my real problem and would like to keep this repair as painless as possible. On this particular engine the points & capacitor are mounted external to the flywheel in a box on the side of the engine, but I appreciate your advice about not removing it anyway.

pugs
08-27-2010, 04:33 PM
I just looked this up and cant find a type 0732...but there are 0733-0739.

They dont show the points coil forwarding to the non points coil on these engines like they do on most of them so you may have the wrong parts coming.

The right coil for your engine would be a 298968.

398811 is used on later dates of your engine so it may work...but usually they forward the older parts to the electronic coil if that is the case.

Is this an old Cast Iron briggs by chance?

Restrorob
08-27-2010, 08:38 PM
You may be right pugs,

I didn't go to Briggs to look this up, I whipped open my Rotary catalog and the 398811 is listed as fitting 7 thru 16hp single cylinder engines both horizontal and vertical. And we all know the old 326400 series 16's were iron blocks.

If you look at 0733 type number engine it's shown with the magnatron bug that can be installed on the 298968 coil and the coil appears to look the same as any other.

We also know that type numbers denote different charging systems/air filters/throttle controls etc on the base model series engines, Therefore the coil mount post should be the same on all engines in that series.

I haven't a clue as to why this 298968 coil doesn't supersede to the 398811, Maybe a error in Briggs part ?

Since the magnatron is listed, All Larry has to do is take his old coil to a local dealer and match it up with a 398811.

pugs
08-27-2010, 08:46 PM
Yah I really dont know as they list the Magnetron for models after 81 code date for the 0733 or others. And the flywheel doesnt change....so I would think it should work but no clue. I did not pay attention whether there were different keys and they dont give info on the block itself...so if the flywheel, key and block mounting for the coil are all the same...I dont see why the magnetron would not work.

I just thought it might be iron because it has that separate oil pan. I am not familiar with Briggs vintage the time of my birth LOL.

Could be an error on briggs part but my distributor has like 30 of those old coils in stock and their system doesnt forward them....so guessing there might be a reason for that.

LarryF
08-28-2010, 11:20 AM
I just looked this up and cant find a type 0732...but there are 0733-0739.

They dont show the points coil forwarding to the non points coil on these engines like they do on most of them so you may have the wrong parts coming.

The right coil for your engine would be a 298968.

398811 is used on later dates of your engine so it may work...but usually they forward the older parts to the electronic coil if that is the case.

Is this an old Cast Iron briggs by chance?

pugs,

Thanks for the concern and the warning, but I hope you are wrong. I checked with a different source and it indicated that Restrorob gave me the right info (which by the way he has a reputation at this website for doing). The on-line store I ordered the unit from also provided a list of all Briggs engines with which the 398811 is compatible. Here is that list, and my engine is highlighted.

So if what I get turns out to be the wrong thing, I'd guess the supplier shouldn't have a problem taking it back.

scottr 2006
08-28-2010, 12:14 PM
It's a 10HP B&S
Model 243432
Type 0732-01
Code 7908281

Problem is no spark. Plug, points and condenser seem to be ok, and I didn't see any wire breaks in the vicinity of the coil when I removed the recoil starter assembly. I set the points at 0.020", but I don't see any sparks when I pull the starter cable. I'm thinking it might be the coil, but I don't have the engine parts manual and can't find any reference to it on the web, so I don't know which coil to order.

Can anyone help or perhaps suggest what else might be the problem?

Did you check the condenser with a ohmmeter to verify that it is not open or leaky ?

LarryF
08-28-2010, 01:57 PM
Did you check the condenser with a ohmmeter to verify that it is not open or leaky ?

Yes, I did. And even though it seemed to be ok, I bought a new one anyway and tried it without success. I admit that this no-spark situation had me stumped, so it left only the coil as a potential culprit. After my original post, I was able to find the owners manual on the web that identified the part number for the original coil. Since it's only a few bucks less than the 398811, the electronic one seemed like a good choice because I'm not too sure of the wiring from the coil to the points & condenser, nor of the one to the plug for that matter. Sure hope this works.

LarryF
08-30-2010, 11:37 PM
Restrorob,

Looks like I struck out. Still no spark with the 398811 installed and the wire going to the old points and condenser disconnected. I set the gap as you advised with a business card and then even reset the gap a couple of times to .010" per the enclosed instructions, first using the tab that was provided and then using a feeler gauge. Still nothing. Even while holding the terminal of the spark plug wire with one hand as I pulled the engine through, slowly at first and then faster, I couldn't feel anything. Is there any way I can bench test this 398811 with a volt-ohm meter?

The old spark plug looked good, but I replaced it with a new one anyway. Didn't make any difference.

Larry

Merkava_4
08-31-2010, 05:01 AM
All you have to do is remove the old coil and install the new, Use any business card between the new coil and flywheel to set proper air gap.


You forgot the step where you pound the plug into the plunger hole.

Unless you want the guy to have oil shooting out all over the new Magnetron coil. :D

LarryF
08-31-2010, 08:47 AM
You forgot the step where you pound the plug into the plunger hole.

Unless you want the guy to have oil shooting out all over the new Magnetron coil. :D

I'm glad you brought that up, because the note Briggs provided baffled me too. It says:

"Plunger Hole Plug Instructions

If engine is equipped to operate with breaker point ignition, discard plunger hole plug.
If engine is equipped to operate with Magnetron or Magnevac ignition, install plunger hole plug as shown.
CAUTION: Crankshaft must be assembled in cylinder before installing plunger hole plug."

And they it shows a picture that doesn't really look like any part of my engine. If by "plunger", they mean the thing that opens and closes the points, mine is in a separate box cast into the engine apart from the location of the flywheel. I presumed that the wording of the first line should have been "If engine had been equipped..............", but since no plunger plug was provided in the Briggs-labeled box the new coil came in and mine originally had been a breaker-point ignition, I just ignored that step. I don't see any oil coming out of the engine. Did I do right?

BigFish
08-31-2010, 10:15 AM
Didn't that list of model no's attached to your prev. post mention that it wont work on old cast iron engines? Is your motor cast iron? Could be your problem.
You may have to get a new coil, points, etc. Or you may be able to fit a magnetron module, as per Restrorob's " bug".

LarryF
08-31-2010, 11:27 AM
Didn't that list of model no's attached to your prev. post mention that it wont work on old cast iron engines? Is your motor cast iron? Could be your problem.
You may have to get a new coil, points, etc. Or you may be able to fit a magnetron module, as per Restrorob's " bug".

I noticed that remark too, and pugs mentioned it too. Well, yes it is a cast-iron engine, but I didn't understand what the significance or "old" meant. Since it specifically identified my engine number (243432) as one on which it would work, I just assumed mine didn't fit into that "old" category.

I also don't know what the magnatron bug Restrorob mentioned might be, perhaps someone can elaborate on that. Well, I'm still in the dark about this, so all suggestions are appreciated. In one of my previous posts I asked whether one could test this 398811 with an ohm meter. I once had a coil problem with the Kawasaki on my ZTR that I had identified by measuring the resistance between the plug wire and engine ground, and a new coil solved that problem. When I made a similar measurement with the 398811, I got about 50 Kohms. Does anyone know if that sounds like it's correct?

Restrorob
08-31-2010, 07:26 PM
You forgot the step where you pound the plug into the plunger hole.

Unless you want the guy to have oil shooting out all over the new Magnetron coil. :D


:nono: . :weightlifter:


Just cut the wire coming out of the points cover and leave the points/condenser in place.


As long as the points are left in place the plunger will be also so no chance of a leak or need for the plug, Unless it was leaking before hand. http://www.ostfriesenpower.org/neues.htm/e124.gif


Larry,

I'm not sure what to think of this no spark, Even if the timing were different on your engine it would still have to spark every time the magnet goes by the coil.

I tried to install a magnatron module on a early iron 16 about 15 yrs. ago, The timing issue came in to play and the engine ran like crap but it still sparked and ran ?

Sorry Larry but I gotta ask, When you mounted the coil did you mount it with the kill wire spade connector closest to the cylinder fins (plug wire facing you) ?

I've never seen any test specs for meter testing these Briggs coils, But I did throw my meter on a new one from stock and got the same spec you did.....

LarryF
08-31-2010, 09:30 PM
:nono: . :weightlifter:





As long as the points are left in place the plunger will be also so no chance of a leak or need for the plug, Unless it was leaking before hand. http://www.ostfriesenpower.org/neues.htm/e124.gif


Larry,

I'm not sure what to think of this no spark, Even if the timing were different on your engine it would still have to spark every time the magnet goes by the coil.

I tried to install a magnatron module on a early iron 16 about 15 yrs. ago, The timing issue came in to play and the engine ran like crap but it still sparked and ran ?

Sorry Larry but I gotta ask, When you mounted the coil did you mount it with the kill wire spade connector closest to the cylinder fins (plug wire facing you) ?

I've never seen any test specs for meter testing these Briggs coils, But I did throw my meter on a new one from stock and got the same spec you did.....

Good question! No need to apologize since if I did it wrong it will be 180 degrees from the correct orientation. The installation instructions made no mention of the proper orientation, but here's a photo of it. I had presumed the spade connector should be on the outside for easy access, so that's what I did.

By the way, that rusty terminal connector to the left of the 39881 has a wire that goes to the points/condenser, and it used to the connection point to a low-voltage wire coming from the old coil. So when I removed that coil, that wire came with it and I made the disconnection at that point. I left the wire to the points alone thinking if someone ever wanted to go back to the original coil, the wire to the points would already be in place.

Restrorob
08-31-2010, 09:40 PM
Turn the coil around and see if you don't get spark, Go ahead and plug the new kill wire on before you re-mount the coil. Run the other end out through the backing plate next to the plug wire or that other hole with that wire, This will go to your kill switch.

BigFish
08-31-2010, 09:45 PM
Again, according to the chart you attached to a prev. post it stated that the flywheel has reversed polarity and the magnetron won't work!

Restrorob
08-31-2010, 10:12 PM
BigFish,

If you look at this link Larry posted; http://www.outdoordistributors.com/briggs_and_stratton/briggs_part_lists.html It shows that all 243400 thru 243499 engines have the same part number flywheel. I wouldn't think Briggs would list a magnatron module for a reversed polarity flywheel ?

Sooo, What do they call a "old" cast iron engine ?

pugs
08-31-2010, 11:09 PM
BigFish,

If you look at this link Larry posted; http://www.outdoordistributors.com/briggs_and_stratton/briggs_part_lists.html It shows that all 243400 thru 243499 engines have the same part number flywheel. I wouldn't think Briggs would list a magnatron module for a reversed polarity flywheel ?

Sooo, What do they call a "old" cast iron engine ?


I am thinking briggs reversed polarity of the magnet on the flywheel but never changed the part number. Probably doesnt matter what polarity you use with points so why bother making 2. If you have an older engine...pre 81 or wherever the code break is you may be stuck using points for this reason...might be why they dont forward the old coil to the new magnetron coil. I am just guessing here. Briggs considers anything this old to be an antique LOL.

Briggs has no test for the coils other than hooking up a spark tester and spinning the flywheel. Honestly the Japanese one give you ohm readings but they are generally useless. You are better off just checking for spark. I have had Hondas test bad that work fine and ones that test good and wont make spark ever.

LarryF
08-31-2010, 11:19 PM
Turn the coil around and see if you don't get spark, Go ahead and plug the new kill wire on before you re-mount the coil. Run the other end out through the backing plate next to the plug wire or that other hole with that wire, This will go to your kill switch.

I did as you suggested, but still no spark.

Focusing on what BigFish has been referring to, someone outside of this LS forum has suggested to me that I can send the flywheel to B&S along with an explanation of what is happening and they will reverse the polarity of the magnets and send it back. I have a name and address, but I haven't yet contacted the person because I don't have a phone number or email address. But I'll try to get in touch with him tomorrow. Supposedly, the service is free except for the out-bound freight charge. But I'll have to admit, Restrorob, that I see your point that this 398811 is what B&S recommends for my engine, so it seems strange that I should need to have the polarity of the flywheel reversed. My reservation in doing this is ...maybe this won't work either, then what? As it is now, I could return the 398811 and order the a new 298968, which is the original armature-coil used with points and condenser.

Restrorob
08-31-2010, 11:36 PM
As it is now, I could return the 398811 and order the a new 298968, which is the original armature-coil used with points and condenser.


Well Larry,

Since no one knows what their doing (Briggs or myself) maybe you'd be better off getting the proper coil and a new set of points since you already have the new condenser.

Sorry for all the aggravation...... :hammerhead:

pugs
09-01-2010, 12:49 AM
Is the magnet strong? Like pull a screwdriver in from an inch or more away strong?

Have you tried this coil with no kill wires attached to it? Just wondering if its in your wiring. I would say do one final try with the Magnetron on the engine. Hook up a known good spark plug. Spin the engine one way and see if there is spark..if not, try going backwards.

LarryF
09-01-2010, 07:56 AM
Is the magnet strong? Like pull a screwdriver in from an inch or more away strong?

Have you tried this coil with no kill wires attached to it? Just wondering if its in your wiring. I would say do one final try with the Magnetron on the engine. Hook up a known good spark plug. Spin the engine one way and see if there is spark..if not, try going backwards.

Pugs,

Seems strong to me! When I was installing the 398811 and adjusting the gap , the magnet pulled it in with a strong force. As far as wiring is concerned, since the points are no longer being used, there isn't any wiring except for the one to the spark plug. And yes, I did buy a new spark plug. So far, I didn't hook up the kill wires. My engine doesn't have a kill button yet. It's one of those old ones that requires the plug to be shorted in order to stop the engine. I was thinking I would jury rig a door-bell button somehow to the new kill-button wire if I ever got the engine running again.

I'm starting to think that even though the engine serial number (243432) remained unchanged since 1979 when mine was manufactured, something about the flywheel, like the polarity, did change in 1981. But I don't have a clue as to how to find out more about that. Anyone know?

scottr 2006
09-01-2010, 09:49 AM
Pugs,

Seems strong to me! When I was installing the 398811 and adjusting the gap , the magnet pulled it in with a strong force. As far as wiring is concerned, since the points are no longer being used, there isn't any wiring except for the one to the spark plug. And yes, I did buy a new spark plug. So far, I didn't hook up the kill wires. My engine doesn't have a kill button yet. It's one of those old ones that requires the plug to be shorted in order to stop the engine. I was thinking I would jury rig a door-bell button somehow to the new kill-button wire if I ever got the engine running again.

I'm starting to think that even though the engine serial number (243432) remained unchanged since 1979 when mine was manufactured, something about the flywheel, like the polarity, did change in 1981. But I don't have a clue as to how to find out more about that. Anyone know?

Many years ago a friend told me that his 5hp Yazoo flywheel was pulled with the hammer/screwdriver method and it hit the cement wall. It would not spark after new points and condenser. Did the flywheel take a hit ?

LarryF
09-01-2010, 11:40 AM
Many years ago a friend told me that his 5hp Yazoo flywheel was pulled with the hammer/screwdriver method and it hit the cement wall. It would not spark after new points and condenser. Did the flywheel take a hit ?

No, and as far as I know, this flywheel has never been pulled.

I still have the old armature-coil and wish there were some way to have it tested. I don't really know if it's bad, but the spark stopped mysteriously when it was on the engine. Plug, points and condenser are all ok and I couldn't find any wire breaks, so I assumed it had to be the coil. But now that this new electronic ignition coil doesn't provide a spark either, maybe it's something else.............but I can't imagine what it might be.

Remember the old saying that "the hardest part of solving a problem is finding out what the problem is!" That sure seems to be the case with this one.

scottr 2006
09-01-2010, 12:59 PM
Have you measured the primary and secondary resistance of the original magneto armature ? Also have you measured to assure that the primary and secondary windings are isolated from the laminations ?

LarryF
09-01-2010, 01:26 PM
I did, but now I forgot the readings and I didn't know what they should be anyway. I did it to see if they were open or shorted. But I'll do it again tomorrow when I have some free time. Do you know what they should be?

scottr 2006
09-01-2010, 01:46 PM
I did, but now I forgot the readings and I didn't know what they should be anyway. I did it to see if they were open or shorted. But I'll do it again tomorrow when I have some free time. Do you know what they should be?

I don't know the specs for your magneto armature but I have a 3hp B&S magneto that is good for comparison . Another question would be, did you clean any corosion off the mounting surfaces of the magneto ?

LarryF
09-01-2010, 03:42 PM
I presume you mean did I clean up the original one. No and not only is it very rusty, but some of the laminates are separating from each other. That's another reason I thought of replacing it. When I started this thread, I didn't have the part number, but since then I found the parts list for B&S Series 243400 to 243499 on the web, so now I do.

scottr 2006
09-01-2010, 05:32 PM
I presume you mean did I clean up the original one. No and not only is it very rusty, but some of the laminates are separating from each other. That's another reason I thought of replacing it. When I started this thread, I didn't have the part number, but since then I found the parts list for B&S Series 243400 to 243499 on the web, so now I do.

The ground circuit being rusty is not good. The mounting surface on the engine also needs to be clean, it's part of the circuit to the threads of the spark plug. A former neighbor from Florida told me that he had to sand the rust off the flywheel of his mower to get it to run.

BigFish
09-01-2010, 08:04 PM
BigFish,

If you look at this link Larry posted; http://www.outdoordistributors.com/briggs_and_stratton/briggs_part_lists.html It shows that all 243400 thru 243499 engines have the same part number flywheel. I wouldn't think Briggs would list a magnatron module for a reversed polarity flywheel ?

Sooo, What do they call a "old" cast iron engine ?

Dunno......do know it's 30+ years old, time to buy a new one.

LarryF
09-02-2010, 08:53 AM
Dunno......do know it's 30+ years old, time to buy a new one.

Well, that's right, it's more like 31 years old rather than just the 20+ I had originally posted. And a new engine is certainly an option I might consider. But on the other hand, the one I'm having a problem with has good compression, has no oil leaks, has only a few hundred hours on it, and did run well before this no-spark issue came up. It seems unreasonable to trash it only because a less-than-$50 part failure. I think the light bulb will go on eventually and I'll get it running again. Thanks everyone for all of the help. I really appreciate it.

LarryF
09-16-2010, 03:39 PM
I just looked this up and cant find a type 0732...but there are 0733-0739.

They dont show the points coil forwarding to the non points coil on these engines like they do on most of them so you may have the wrong parts coming.

The right coil for your engine would be a 298968.

398811 is used on later dates of your engine so it may work...but usually they forward the older parts to the electronic coil if that is the case.

Is this an old Cast Iron briggs by chance?
Well pugs, you were right about a couple of things. First of all, I made a typo and itís really a Type 0762 rather than 0732, and more importantly, the 398811 didnít work, as you seem to have suspected. It took me a while to find out why, but I think I got it now. When Briggs converted from points & condenser to electronic ignition in 1981, it also changed the design of the flywheel slightly in that the polarity is revered from what had been provided previously. The Briggs literature didnít explain this too well, and although the IPL for that engine indicates the 298968 coil is to be used on engines made before 1981 and the 398811 on engines after 1981, the same document doesnít provide that kind of note for the flywheel even though there are also two of them, 395250 and 395269. Seems to me that they should have. I also found out that I could have send my flywheel back to Briggs (I have the address if anyone is really interested) and it will reverse the polarity free of charge and return it to me if I really want the electronic ignition the 398811 can provide. However, I decided that this was getting to be more trouble than it was worth, so I just traded the 398811 coil I had gotten for a 298968 and now Iím back to the points & condenser configuration. Everything is working as it should and for today at least.

Thanks for the help!

scottr 2006
09-17-2010, 09:49 AM
Larry, did the original magneto/coil have a high voltage burnt ozone smell ?

LarryF
09-17-2010, 11:09 AM
Larry, did the original magneto/coil have a high voltage burnt ozone smell ?

I didn't notice that. It was running ok one day, and the next day it wouldn't fire up. When I went through the usual test procedure, there was no spark. Points, condenser and plug were changed but it still wouldn't start, so the coil was the only logical thing left to focus on. I had bought the machine used, so I don't know the repair history, but it had some rust, most of which I have now cleaned up. That rust wasn't too serious in my opinion, but I presumed it had been left outside a lot. When I took off the recoil-starter housing, I saw that the coil was badly corroded and de-laminated, so I suspect it had never been changed before. A failed coil after many years didn't seem too surprising to me since one of the ignition coils on the Kawasaki of my ZTR failed before it had even a couple of hundred hours on that engine.

scottr 2006
09-18-2010, 10:42 AM
Larry, check your private messages.