QuestionHello.. My Son in Law has an MTD mower with a 14 hp B & S. engine. It is about 5 years old. From day one, it has been extremely hard to crank.. It comes up against compression, and the starter simply will not push it. If you bump it a few times, eventually the compression drops enough that it will crank on over, and eventually, it will crank through enough revolutions to start. We have replaced the starter with a new one, jumped it directly to the starter, bypassing the mower cables, using a heavy duty car battery. Thinking it might be too much compression caused by carbon builup I pulled the head, cleaned out the carbon, etc. The problem is worse, after being stored for the winter. The belts seem to be adjusted ok. The blade drive belt does not bind. The transmission belt is tight, but with the trans in neutral, doesn't cause any reisistance to the engine.The engine turns freely with the spark plug out. Again, a new starter didn't cure the problem. Once it starts it runs fine, idles great, etc. It just seems to have too much compression for the starter to crank it.
Is there an aftermarket compression release we can install? Other than that, a beefier starter, or two head gaskets to lower the compression. I have read the suggestions that have been made by others.. but it doesn't work for us. Maybe set the intake valve lash closer than specs?
Help!!
Thanks
Rolin Brown
Answer Hello Rolin:
There are 3 Common Causes for this Problem. 1- Battery CCA to Low. ie 150 CCA VS 225CCA (Cold Cranking Amps). Also under this Cause is the Battery Cables (Batt to Soleniod, Soleniod to Starter and Batt to Ground). Most Mowers Actually Need larger Cables then are Installed. Increasing the Cable Size Allows More Amperage to go to the Starter. The Starter Starving for Amperage Causes this Problem. 2- The Flywheel Key is Bad. Just a Slight Nick in the Klywheel Key will throw the Timing Off and Cause the Problem. 3- The Coil is Loose. This Throws the Timing Off.
Good Luck
Respectfully
John
