ron and kristins starter comparisons..

[robertglines1]

Electrical note  wire guage white wire on new starter appears to be lighter than black wire on old starter. Cold cause low amperage problem and over heating of wire.  Bob   Not trying to pick just observing.

[luvrbus]

T, the MT 42 starter should cost 200 to 250 bucks tops is the there a rebuilder in your area ? sorry I don't have a lefty starter or I would send it to him I have plenty of the rights

good luck

[Lin]

An auto electric shop should be able to rebuild the original starter.  I think I paid about $200. for that last year.  They may even be more expert at seeing the difference between the two.

[Lonnie time to go]

would a starter off a 4905 8v71 be what is needed

I wonder if all 8v71 starters are interchangeable if the direction is the same

what is  your location   state and city

Lonnie

[JackConrad]

would a starter off a 4905 8v71 be what is needed
I wonder if all 8v71 starters are interchangeable if the direction is the same
what is  your location   state and city
Lonnie

I think so (in bus applications at least), except the nose cone may need reindexed.  Jack

[luvrbus]

The starters are different according to the starter location on the bell housing a 8v71 righty can use 3 different starters not being a GM guy they could be the same starter location is the key for the right starter

good luck 

[JohnEd]

That trip to the re-builder is a terrific one.  I am a firm believer in "experts with experience".  The beauty here is you might be able to use things like the solenoid, armature and body to swap over to your old parts and come out of it with no more invested than the charge for that at the starter shop.

I understand that the starter is criminal to replace so I guess this is the time to get a expert on site involved.

John

[happycamperbrat]

Im at work now, but will make sure Ron sees all this when I get home. Im in Ridgecrest, Ca  http://maps.google.com/maps?q=4756+sydnor+ridgecrest,ca&oe=UTF-8&ie=UTF8&hq=&hnear=4756+Sydnor+Ave,+Ridgecrest,+California+93555&gl=us&z=16 They are really nice folk and it's a pleasure having them, but I sure would like to see them get on the road in a bus that will get them home.

[JohnEd]

YOU ARE NOT WIRED CORRECTLY!

My ecpert just reminded me of the way the starter works.  First, the way an automobile worls.  The solinoid engages the bendix and connects the starter motor to B+.  The solinoid stays connected and "working" throughout the start.  This bus thing is designed to use the solinoid to engage the bendix and then when the armature gets engaged THE B+ FOR THE SOLINOIOD IS INTERUPTED and the B+ for the armature gets connected to the solinoid to KEEP the bendix engaged.  If the starter solinoid wiring gets reversed then the "GROUND" is used to keep the starter engaged.....that won't work.  That massive starter, when miswired like this, will "chatter".

The FIX.  Solinoids are not themselves polarity sensative but they need to be in the circuit correctly.  Look at your old solinoid/starter and carefull match that wireing config to your "new" starter.  This is a common mistake and easily corrected with wireing properly connected.  You have the correct wiring in the example of the old starter.

This info comes from a starter  rebuild shop and is filtered through me.  Any one should be able to get the same story from any shop.

Good luck,

John

[JohnEd]

You can verify this "theory" by connecting the starter to a battery and shorting the solinoid engage terminal to "Bat".  HANG on as the thing will try to leave the premises.  If it wired incorrectly then it should chatter.  Try the old one too.  They should react the same and be wired the same.

I think you are fixed.....good luck,

John

[MDV Maria V]

Update this am:   Old starter when jumped, solenoid only throws sparks, no movement.  New starter when bench tested, functions properly; first bench test procedure was to disconnect all three bolts and back starter away from fly wheel.  Reconnected battery cables at battery connections- did not remove any cables from starter for this test, only pos and neg at battery. Starter engaged and ran smooth and strong with no load.  All measurements and apparent visuals between two starters would appear that they are the same starter, turn the same direction,  only apparent difference is different solenoid.  Now under impression that this is possibly a relay issue to solenoid, causing chattering under load and am regoing over all cable connections to assure that they are clean and properly connected.   Ron will put starter back in, test and if cables are not the issue, will test by jumping past relay.  Will report back soon, thank so much for helping!

[luvrbus]

You have a wiring problem some place the engine starts and for what ever reason it is engaging the starter while the engine is running that is what is chewing the bendix drive up and causing the discharge on the gauge George will help you figure it out when he gets there and if you think it is a relay make your self a jumper and by pass the relay but I don't think that is the problem.I would also check the flywheel and be sure it hasn't come loose the old style 8v71 are bad about breaking the bolts if not updated to the 2 extra bolts in the crank end

 

good luck

[happycamperbrat]

On aside..... how did you know by looking at these pics it was left hand rotation and not right hand? Im still confused by how to tell the difference.....

[luvrbus]

The twist for the right hand, left hand deal is on the armature shaft inside the starter you need to pull the nose cone to see that

good luck

[happycamperbrat]

Thanks for the explanation