CA running rough
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=14388
Printed Date: 02 Feb 2025 at 10:50pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: CA running rough
Posted By: Leon B MO
Subject: CA running rough
Date Posted: 26 Jun 2010 at 4:23pm
|
About halfway done mowing the other night and out of nowhere everytime the govenor would kick in, it would cut out, miss and sputter. If I pulled the trottle back a notch or 2 it seemed to help alittle. It might run fine for 5 minutes and then as soon as the gov kicked in it would cut out. Today I installed a carb from a good running CA and made sure I had good fuel flow through bowl and line to filter(did find a little piece of O-ring in the sediment inlet, I thought I had the problem solved) started the tractor and runs even more poorly than before, like whatever the problem is, it's geeting worse. I need to put a timing light on to see if spark is cutting out but any advice in the mean time would be helpfull.
Thanks
Leon B
-------------
Uncle always said "Fill the back of the shovel and the front will take care of itself".
|
Replies:
Posted By: CTuckerNWIL
Date Posted: 26 Jun 2010 at 4:35pm
I think I would do a tune up. At least check to make sure you have a good sharp blue spark.
-------------
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: Brian Jasper co. Ia
Date Posted: 26 Jun 2010 at 5:46pm
Put new points and condenser in it and try again. It takes more coil output to fire when engine load increases. Don't forget to check the distributor shaft for looseness. If the shaft has any play in it, it will be impossible to accurately set the points, plus the timing will never be constant. I'm a fan of the electronic conversions. Both of my gas tractors have them and run like Swiss watches.
-------------
"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: Leon B MO
Date Posted: 26 Jun 2010 at 6:18pm
|
What would it cost to convert to electronic ignition, the points and condensor are about year and half old and when I set the points then it ran better than ever.
Leon B
-------------
Uncle always said "Fill the back of the shovel and the front will take care of itself".
|
Posted By: Gary in da UP
Date Posted: 26 Jun 2010 at 6:30pm
|
A pertronix will run $85 or so depending on the vendor.And a pertronix will allow a wider gap on plugs and compensate for a little slop in distributor shaft bushings. I think they are great. Planky don't like them, but he has a problem with plasma under his cap, so he says.
|
Posted By: Leon B MO
Date Posted: 26 Jun 2010 at 6:32pm
|
Looks like 122 for the conversion at Tony's. Does it replace the whole distributer, would it solve the problem of loose shaft? I don't know anything about the conversion. Thanks
Leon B MO
-------------
Uncle always said "Fill the back of the shovel and the front will take care of itself".
|
Posted By: caRon
Date Posted: 26 Jun 2010 at 6:53pm
|
I've had new condensor's go bad after a short period of time. Under load or when hot they'll kick out. Might try and swap one out just to be sure. Ron
|
Posted By: GregLawlerMinn
Date Posted: 26 Jun 2010 at 7:57pm
|
If you have a 12 volt ignition (neg grd) I would recommend the Petronix EI kit. I now have them in most of my tractors, and will be adding them to the others in the near future). Installs in just a few minutes (pull the points & conensor, install the module where the points were, and slide the plastic thing over the shaft, hook up the wiring, replace the rotr/cap and you are done). You may have to retime the engine it after it is installed. Have heard mixed reports about the 6 volt EI modules.
-------------
What this country needs is more unemployed politicians-and lawyers.
Currently have: 1 D14 and a D15S2.
With new owners: 2Bs,9CAs,1WD,2 D12s,5D14s,3D15S2s, 2D17SIVs,D17D,1D19D;1 Unstyled WC
|
Posted By: Gary in da UP
Date Posted: 26 Jun 2010 at 8:09pm
|
I agree with Greg, I would only install with a 12v system, I don't think a 6v pertronix would be that hot, but then I don't have any exprience with a 6v pertronix. I think I'd rather have a good mag.
|
Posted By: Leon B MO
Date Posted: 26 Jun 2010 at 9:26pm
|
This CA has 12 volt neg ground, I am seriously thinking about the electonic ignition in the near future but for now I will put in a distributor from another running CA and see if that gets me back to mowing. Thanks everyone for the info, I'm going to print this and keep it for future reference. Where is the best place to get the Petronix EI.
Leon B MO
-------------
Uncle always said "Fill the back of the shovel and the front will take care of itself".
|
Posted By: Fred in Pa
Date Posted: 27 Jun 2010 at 7:35am
|
I have installed MANY 6 volt kits. If the starter and generator along with all electric system is in good working order they work fine.
|
Posted By: ohnomrbill
Date Posted: 27 Jun 2010 at 8:33am
FWIW I inetalled a Pertronix kit on my B and it made a huge difference in how well the tractor ran. Best $$ I've spent so far on the B. Best part - no more points to adjust or wear out.
-------------
1949 and 1952 WDs
|
Posted By: DaveKamp
Date Posted: 27 Jun 2010 at 9:36am
"Planky don't like them, but he has a problem with plasma under his cap, so he says.
"
According to my wife, we ALL have problems with a little plasma under our caps...
Or mebbie it wasn't plasma.... something like that.
The Pertronix Ignitor is nothing more than a passive triggering unit- there's a really stout semiconductor in there, and a detector, probably hall-effect or reluctance coil (like a guitar pickup coil/magnet) that detects little vanes on a card that slips over the distributor shaft. Everytime a vane comes by, the detector triggers the semiconductor, and causes it to pass current through the coil.
The advantage to such devices, is that there's no 'gap' involved, and no mechanical actuation, so there's no friction, no wear, no drag, no variation, there's no resistance (across dirty contacts), so they'll either work, or they won't. Finally, if you inadvertently leave the key on (like... you turn off the gas to run it out of fuel), and forget... you won't wind up with a dead battery.
The downsides are that, they either work, or they don't- if there's a problem, you can't 'adjust it out' to get it out of the field. Also, since the triggering is done by a semiconductor, it imposes the basic 0.60v 'drop' across the semiconductor junction. This is insignificant at 12v, but at 6v, that means your coil is getting 5.2v... and some people have a 'scholastic issue' with it. In reality, those who've had poor performance likely had this 0.6v penalty included with the penalty of poor battery/cable/coil/coil wire issues amounting to more like 4.8v (where points would only give them 5.2v)... but I've used 'em on many occasions, and found that they work just fine, and always better than contact points.
The final downside (and this only occurs under extreme conditions) is that ANY reluctance or hall-effect type sensor can be false-triggered by ambient magnetic conditions... anything that 'seems' like a magnetic change can trigger a hall-effect or reluctance sensor. Good example is if you take a cordless drill, and operate it in front of an electric guitar, you'll hear the motor running. In the case of a distributor-mounted sensor, a short (particularly high-voltage short in the rotor) can oftentimes yield a discharge path-to-ground for high voltage that was intended for a spark plug. Usually, this discharge goes right through the rotor, down the rotor shaft, and then to block, burning away at everything in the path... distributor shaft bearings, oil pump gears, advance weights, condenser... anything else that looks attractive to a discharge. Of course, false triggering meant that there were more spark events, causing more misfires, more stray shorts, and more misfires, with the commensurate more welding going on. This was frequently observed with the old GM 'coil-in-cap' HEI system, as the coil's magnetic field was close enough to affect the distributor's trigger... hence the reason why GM discontinued it and went to the external-coil EST system.
By the way... the amount of spark energy required, is a function of compression pressure... if you're running standard compression on these old tractors, and relatively speaking, it doesn't take much to make 'em run, but what you see with the plug out, and what happens with the plug IN are two totally different atmospheres. IF the ignition system (mag or battery/coil) appears to throw a good spark, but it won't run, the ignition system most likely IS the problem... the spark you got looks good in free air, but once compression pressure is applied, the spark isn't nearly as effective. Oftentimes, lackluster ignition performance can be detected by noting how well an engine starts cold. If it doesn't seem to want to start without cranking fast, or it's REALLY picky about overchoking, you likely need a bit more spark energy.
One of the silly, but true truths about hand-start magneto ignited engines, is that they're better maintained... when right, it usually only takes one well-charged cylinder, brought over-center, with a good magneto/impulser CLACK to fire off that first event, therefore kicking it to life. Rare to find electric-started battery-coil engines that'll do that.
This isn't saying that you need a high-performance ignition system to make it run well- just a good, well-attended stock system will do fine. If you're bumping up to 17:1CR and running on methanol, though, you'll be fighting Mother Nature to put fire in the holes.
|
Posted By: Leon B MO
Date Posted: 27 Jun 2010 at 10:14am
|
I started early this morning to beat the heat, I put a coil and points in from a running CA. When I took the points out, I was shocked, they were burnt up and they are only a year and half old. Anyway, I'm back to mowing, and will install a new electric system soon. Thanks everyone for the info and help.
Leon B MO
-------------
Uncle always said "Fill the back of the shovel and the front will take care of itself".
|
Posted By: Dave(inMA)
Date Posted: 27 Jun 2010 at 11:15am
|
Leon, I had some discussion with Steve Barbato about the cause of burned points. I'm sure that Steve will correct me if I have this wrong!
I THINK I am recalling correctly that a mismatched coil can cause that kind of damage. Some coils are designed for 4 cyl engines, some not. The "nots" will burn the points. If one of the "nots" is installed on your CA, this could be the cause of the burned points.
-------------
WC, CA, D14, WD45
|
Posted By: Leon B MO
Date Posted: 27 Jun 2010 at 1:42pm
|
I didn't realize a coil is for a spacific # of cyl. I thought a 12v coil was indiscriminent on whether it's 4,6 or 8 cyl. It's running great now and I am pretty sure I will convert it over to an electronic ignition this winter. But thanks for the info.
Leon B MO
-------------
Uncle always said "Fill the back of the shovel and the front will take care of itself".
|
Posted By: pumpkin man
Date Posted: 27 Jun 2010 at 5:34pm
|
A coilcoil is acoil 6 volt or 12 volt put a ballast restor befor the coil this will stop the points from burning works fine on 11 a/c tractors & 1 J D
|
Posted By: Brian Jasper co. Ia
Date Posted: 27 Jun 2010 at 10:35pm
I agree with pumpkin man. No such thing as a 4 cyl, 6 cyl, 8 cyl coil. There is also no such thing as a true 6V or 12V coil. You need to check the primary side resistance with an accurate digital ohm meter. A coil circuit intended for use with 12V will have 3 to 4 ohms resistance. A 6V coil circuit will be 1.5 to 2 ohms.
Notice I say circuit. Some 12V gas engines used a ballast resistor with a bypass circuit to get a hotter spark while cranking.
-------------
"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
|
|