MEP-803A battery size

[jamawieb]

The Problem I ran into is the Optima 34/78 batteries have the terminals closer to the center of the battery so the hold down bar isn't and issue. A regular 34/78 battery has terminals that are at the back close to the block and very close to the hold down bar when installed. Not ideal at all. The MT-47/H5-1 is very close in size to the 34/78 but terminals are reversed. it also has a indent on battery where the hold down fits nicely. They don't make a Group 34R (reversed posts) anymore from what the battery dealer said. I have about 30 used batteries around and tried a ton of them to see what worked the best. Hope this helps.

I use 34r from Oreillys and turn the battery around so the terminals are away from the engine and hold downs.

 

[loosegravel]

I know that there may be some "purists" here that won't want to hear this. Using a handheld disk grinder, I've cut the unused mounting ears off of the Lister Petter LMN4 engine on my 803A. It has opened up the possibility of using "whatever you got" for batteries. And, as others have said here on this thread, hold downs can be fabricated fairly easily or purchased from a local auto parts store. I'm not usually a "hack" when repairing anything. But in this case, I felt Ok making this modification and I could justify it.

 

[Light in the Dark]

Those ears are only useable for alternate stationary uses, and being a cast block... You aren't losing any inherent strength with them gone.

 

[loosegravel]

One thing I should add here. If someone uses larger batteries than what was specified for any machine or vehicle, you do run the risk of having too much load on the alternator/charging circuit. If, say those oversized batteries become discharged for some reason and you attempt to charge them with the alternator/charging system, stuff can go wrong. Batteries are really just resistors in the charging circuit. When “good” batteries become discharged, their internal resistance value goes way up, thus causing more amperage on the charging circuit. In the case of the 803A, it could blow the charging circuit fuse when attempting to use the alternator to charge “good” batteries that are discharged. The general consensus here on this forum is to use a trickle type charger to keep your batteries up for this very reason.

 

[loosegravel]

One thing I should add here. If someone uses larger batteries than what was specified for any machine or vehicle, you do run the risk of having too much load on the alternator/charging circuit. If, say those oversized batteries become discharged for some reason and you attempt to charge them with the alternator/charging system, stuff can go wrong. Batteries are really just resistors in the charging circuit. When “good” batteries become discharged, their internal resistance value goes way up, thus causing more amperage on the charging circuit. In the case of the 803A, it could blow the charging circuit fuse when attempting to use the alternator to charge “good” batteries that are discharged. The general consensus here on this forum is to use a trickle type charger to keep your batteries up for this very reason.

I’m wrong again! When a good battery becomes discharged, the internal resistance goes down, not up. Sorry