6 volt Starters

Would appreciate input on the question of improving perormance of 6 volt starter motors. Has anyone had experience with the following suggestions:

1. Shimming field pole pieces to reduce clearance with armature. 2. Removing a few turns from the field coils. 3. Fitting a needle bearing in place of nose bushing ( when applicable ).

Any other ideas ? And not involving switching to a 12 volt battery, checking cables and connections etc. Been there, done that.

hi George..... a friend of mine has a 1939 packard and had starting problems until he bought one of them new style hi-output batteries. its a lil' dinky 6 volt batt that has 850 cold cranking amps. weird looking lil' thing but believe me it sure does the job. the cost of 1 is around $100.00. if i were you i would ask around at batt shops and see if they can get you one.

hope this helps....Ellick:

Some of the guys on the old IHC newsgroup have had good luck with installing 8 volt batteries and adjusting the regulator to match.

The best solution I've ever found was to replace your 6 volt battery with an 8 volt tractor battery. The size is about the same. It will require a minor adjustment to your voltage regulator but will make everything work better. Your starter will whizz without burning up and your headlights will have a bluish tint and will be very bright. Ran an old Beetle like this for many years with no problems. And don't worry about your radio either it will be fine as is.

An 8V battery may be the way to go. Shimming the fields may be a problem as the clearances are fairly small. The sugfgestion about a high capacity 6V battery may work also. Most 6V cars used a group 1 battery. Group 2 batteries were larger and higher capacity, you would need to see if there is room. Some chain stores are still selling small VW type 6V Batteries which have aren't strong enough. Make sure the cables are heavy enough. 12V battery cables won't carry the current of a 6V system. Another suggestion is do a starter draw test and see what the actual current flow is. You sometimes can get away using an inductive ammeter to get a close reading. Let us know what you find out.

The idea of using a higher voltage battery is not a solution to the problem. The major problem with 6 Volt starting is poor grounding through the starter itself. The brushes ground at the end opposite to the drive (and mounting) end. In the motor. Where each part mates, the surfaces must be clean and bright as when new. With use, corrosion builds on these interfaces and grounding is degraded. Try disassembling the starter and drill a hole in the commutator end plate for a 3/8-16 hex head capscrew with a lockwasher and nut on the outside of the plate. . Position the hole (and bolt) so that the head doesn't interfere with the brush rigging and the bolt is in the open when installed. The bolt needs to be long enough for another nut, lockwasher and your battery ground terminal. Ground the battery to this new 'grounding stud'. normal engine grounding will, of course, pass through the starter motor with no problems. This new grounding technique gets the ground right to the brushes with no current path problems. Paint the stud and terminal with black paint to keep future corrosion out. As said here by someone else, don't rely on cables for 12 Volt systems. Make your own from #0 AWG welding cable (or heavier, if you wish), if you need to.

Thanks everyone for your ideas on improving starter performance. Douglas Houston's idea is a new one on me - and sure seems worth a shot. Presumably one should use a copper setscrew and nuts ?

No-one commented on the idea of removing a few field coil turns - I am sure I read that somewhere in a magazine or in a NG some time ago. Does it make electrical sense ( ampere-turns and all that ) ?

Perhaps the easiest and cheapest fix is clean-clean-CLEAN all connections from battery through switches and all connector junctions. Clean right down to bare metal and reassemble using electrician's (dielectric?) paste for a GOOD non-corroded connection. If you are running 6 volt, connecting surface corrosion, even if hidden/barely visible is an absolute killer! If you do this, and also REPLACE wrong cables/wiring with the correct guage ones, there should be NO problem (except with some 2 pole Studebaker starters -) ) Old wiring can have hidden internal corrosion