QuestionQUESTION: It only has 130 hours but it misses at all RPM's. I changed the plugs and one of them was fouled with carbon. I also tried running the engine on one cylinder at a time and it did stay running on each. A local shop recommended I try this to rule out a blown head gasket. The engine does not seam to miss when running on each cylinder individually? The carb has no external adjustments. The engine is on a cub cadet LT1554. I checked the fuel supply and it seams ok but I don't know how to check the fuel pump. It does not burn oil and it has ok power but it misses? Choke is opening properly. Any help would be appreciated.
ANSWER: Hello Tony:
First, you Need to Soak and Clean the Carburetor to Eliminate it as the Possible Cause for this Problem. A Dirty Carburetor will Run 1 Cylinder Properly, But cause a Miss when trying to Supply Gas to 2 Cylinders. It is a Rare Occurrence, but it Happens More than One would Think. Remove, Disassemble and Soak the Carburetor Overnight in Carburetor Cleaner (I Use Gunk). I have Found that Most People can Use a Breakdown/IPL and Disassemble the Carburetor Enough for Proper Cleaning. You Only have to Remove the Bowl, Float Pin, Float (if Applicable) and Needle Valve and Any Adjustment Screws that Go Into the Carburetor Body. The Welch Plugs Do Not have to be Removed. Then Soak the Carburetor Body and Parts in a 1 Gallon Can of Gunk Carburetor Cleaner Overnight. The Can has a Parts Tray Inside it for the Small Parts. Once the Carburetor and Parts are in the Cleaner, you can Replace the Lid for Safety and to Prevent Accidental Spillage. Then Blow Out the Passages with Compressed Air. Install New Parts if Required. Second, The Valve Clearance May Require Adjusting. If the Fuel Pump were the Cause, the Engine Would Run and Quit Completely or Run and Almost Quit then Catch back Up. A Minor Miss while Running is Not a Fuel Pump Problem. You can View a Breakdown of the Mower at this Site Addy, http://www.emerichsales.com/home.asp and Select Shop Online, Parts and Accessories. Then Select the Model Tab. Then Select the OEM (Cub Cadet) and Enter the Proper Model Numbers (Usually Located Under the Seat). Then Double Click on your Model. Now Select the Section of the Mower you Wish to View Online. If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.
Respectfully
John
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QUESTION: John
I soaked the carb and blew it out. It still misses like it did before? Could it be an electrical problem? I also read a possible intake gasket? One thing I noticed is a condensation coming out of the breather separator. not a lot but enough to notice. Does this mean anything? Thanks
ANSWER: Hello Again Tony:
With Small Engines, I Learned a Long Time Ago Not to Dismiss Anything as a Possible cause. It may be the Coil is in the Process of Going Bad. A Valve May have a Burnt Seat. Usually a Bad Intake Gasket will Cause Idling Problems and Power Loss. The Condensation you are Asking About is Common and Not a Worry. It is Actually Gas Moving Inside the Intake. Good Eyes. Most People Miss it. If you Suspect the Intake Gasket as Being Bad, then Replace it. Is the Miss at the Same Interval or Just Missing At Different Times? If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.
Respectfully
John
---------- FOLLOW-UP ----------
QUESTION: John I pulled the shroud off of the engine and checked the wiring going to the ignition coils. I also ohmed them out and they checked out within spec per kohler's service manual. I also checked the coil to magnet clearance's and they were both good. Have you seen many SAM modules go bad and throw off the timing a little? Have you ever seen a flywheel key shear a very small amount throwing off the timing? I read that kohler uses a steel key so this is very rare. I did not check for this condition. Again the engine runs smooth with one cylinder at a time but starts to miss at all rpm's once I attach the other spark plug wire? It is a very slight miss but you can hear it through the muffler with a slight sputter instead of an even tone once in a while. I don't think it is causing the engine to lose power. The SAM module is over $100.00 and I don't want to start throwing that kind of money into it by guessing. How often have you seen a SAM do something similar to this? Thanks for all of your suggestions. I do appreciate them.
AnswerHi Tony:
I have Seen Flywheel Keys have Just a Faint Impression in them and the Timing be Far Enough Off to Cause Backfiring. I have Seen this Happen a Few Times with a SAM (Spark Advance Module) Going Bad. I have Also Seen the Ign Module Itself Cause this Problem. A Bad Lifter will Also Cause this Problem. As you can See, there are Several Possible Causes for this Slight Backfire. I Usually Start with the Flywheel Key and then Using Tester Ign Modules and SAMs I Isolate the True Cause. You can View a Breakdown of the Equipment at this Site Addy; http://www.emerichsales.com/parts-browse.asp and Select the Shop Online Parts and Accessories Online Parts Catalog Box. Now Select the Model Tab. Now Select the OEM and Enter the Model Numbers. You can Also Use the Product Tab if you are having Trouble Locating the Model Numbers. If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.
Respectfully
John
