Miss on 1 and 4
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=139514
Printed Date: 18 Dec 2025 at 5:28pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: Miss on 1 and 4
Posted By: blue924.9
Subject: Miss on 1 and 4
Date Posted: 17 Jun 2017 at 7:57pm
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The wd has a miss on cylinders 1 and 4. When we take spark from 1 and 4 there isn't much change in engine sound. 2 and 3 it starts missing like it normally would. Have checked plugs and swapped them around with no change. All valves are moving and compression is good and equal on all cylinders. This engine is freshly rebuilt. Cam ground to 175 specs and 45 crank. The carb hasn't been touched. It was also converted to distributor. Also tried switching the old and new distributor cap with no change. The cylinders don't seem to be completely dead as it only sounds like a slight miss but pulling the plugs on 1 and 4 doesn't change. Anyone have any ideas ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
Replies:
Posted By: Brian Jasper co. Ia
Date Posted: 17 Jun 2017 at 8:19pm
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Do you have the plugs wires set for 1 2 4 3 firing order? ------------- "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: blue924.9
Date Posted: 17 Jun 2017 at 8:46pm
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Yes it's run for 1243 ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
Posted By: bradley6874
Date Posted: 17 Jun 2017 at 10:29pm
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Is it 1243 the right way around the cap going one way its 1243 going the wrong way makes it 1342 btdt ------------- You can wash the dirt off the body but you can’t wash the farmer out of the heart and soul |
Posted By: blue924.9
Date Posted: 17 Jun 2017 at 10:58pm
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I believe so. According to the manual the distributor . Rotates clockwise which with the rotor off I confirmed it does. From there the wires are routed 1243 in clockwise direction. ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
Posted By: blue924.9
Date Posted: 17 Jun 2017 at 11:09pm
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It seems odd that those two plugs don't change engine note when the wires are pulled off yet the tractor still runs well with a slight miss. Pull two or three of and the tractor behind missing profusely, stuttering and on the brink of dying out. Plug a good one back in and take off 1 or 4 and there is no change. All the spark plugs are getting good spark that will jump a large gap and all the plugs make spark. I have a tester with a new plug an old plug and a window to watch the spark and they all make decent spark but not as good as the new plug. Compression is good as well so that's not the cause either. We are going to change plugs and dyno the tractor to ensure all 4 cylinders are contributing as the miss seems to go away under load in road gear with the brakes on. I will also note that the timing doesn't line up with the mark on the flywheel compared to where it runs. The mark on the flywheel is too retarded. The timing marks are Lined up as well. The only thing is it changed to a 45 crank and used the 45 cam and gear in the wd block. The cam was also ground to 175 specs by Barry's cams I believe in minnesota ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
Posted By: old farmer
Date Posted: 17 Jun 2017 at 11:27pm
| What are your valves set at? My cam done by Barry to 175 spec is to have valve clearance set 18 thousands per there spec sheet with the cam. |
Posted By: blue924.9
Date Posted: 17 Jun 2017 at 11:32pm
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They are set to 18 thousands of an inch warm per the cam card. I also had barry do my cam ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
Posted By: SteveM C/IL
Date Posted: 18 Jun 2017 at 12:05am
| Start over...reset everything...even the stuff you know is right...cause something isn't. Think the fire mark on 45 is 30deg BTC. Too much for higher than stock compression.Guessing the WD flywheel is timed the same? Be sure you are looking at "F" not TDC mark. |
Posted By: blue924.9
Date Posted: 18 Jun 2017 at 12:41pm
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Any idea what timing should be? We ran it until it labored then back until it loaded up and then put it in the middle. Have noticed that 1 and 4 are across each other on the distributor. Swapped cap and rotor with no change. Is it possible it's in the carb? I would think carb would effect all the cylinders though ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
Posted By: DougS
Date Posted: 18 Jun 2017 at 12:48pm
| You've swapped the plugs. Have you swapped the plug wires? Don't merely swap 1 and 4 as both wires my be bad. If that doesn't change anything your problem has to be something other than electrical. |
Posted By: JC-WI
Date Posted: 18 Jun 2017 at 2:07pm
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Maybe it is the distributer lobes are worn, or the bearings on the shaft... "the miss seems to go away under load in road gear with the brakes on." Getting enough fuel in it? Carb to small? using the WD manifold? got an air leak in the manifold gaskets? Identical compression PSI on all cylinders? Or the camshaft is not timed right? Or possibly a degree change got made while grinding camshaft? How many HP is it dynoing at? Maybe just for giggles, swap the wires on the cap from hole one to hole four and four wire to one hole. and see what happens. Have you used a tester for checking continuity in the spark plug wires? Solid core wire or carbon core? ------------- He who says there is no evil has already deceived himself The truth is the truth, sugar coated or not. Trawler II says, "Remember that." |
Posted By: old farmer
Date Posted: 18 Jun 2017 at 3:37pm
| What kind of spark plugs? Most AC's don't like champion plugs |
Posted By: blue924.9
Date Posted: 19 Jun 2017 at 10:33pm
Does yours have a bit more lopw to it now after the regrind ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
old farmer wrote:Posted By: WF owner
Date Posted: 20 Jun 2017 at 5:38am
| Is the advance in the distributor working? It sounds like it may be stuck, if the tractor runs better at full throttle. |
Posted By: blue924.9
Date Posted: 20 Jun 2017 at 7:24am
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It seems to be, everything moves freely and snaps back ------------- hi my names dan, I am a young guy. i have a problem, i prefer my tractors orange and my clutches mechanical, thanks for letting me share |
Posted By: DrAllis
Date Posted: 20 Jun 2017 at 7:28am
| The basic premise of the advance mechanism is at very, very slow idle the timing will be at TDC. At full throttle the timing will be at "F-30" or "F" whatever the flywheel is marked with. One of your posts was asking where the timing should be set at?? sounds like you don't know where it should be. TIMING IS ADJUSTED AT WIDE OPEN THROTTLE TO F-30 OR F. |
Posted By: LeonR2013
Date Posted: 20 Jun 2017 at 8:01am
| I believe I'd check the rockers for wear plus the shaft. They can be worn at the shaft and also where the rockers contact the valve. You might try opening up the valve clearance a few thousands on 1&4 and see if that makes any difference. Do you have a WD or a WD-45 head? Don't know whether if it would make any difference. |