Perkins 4107 starter motor problems

[l'escargot]

Had intermittent starter problems on my 4107 - low cranking speeds similar to low battery power or bad earth. Checked all wiring to battery and solenoid etc. and re did earths. Battery borderline so renewed battery. Problem continued so took out starter and stripped it down to find that the insides, commutator, brushes etc all smeared with copious amounts of grease - it would appear that previous owner thought it all looked dry so "remedied" the situation!

All washed down with petrol, dried off and reassembled.

No problem for a while until yesterday. Switched off engine whilst hot, went to restart a short while later but engine barely turned over - voltage OK in battery. Left for half hour then restarted OK and has done several times since.

Now where do I go?

1 Accept it as a glitch and ignore until it happens (or not) again - possibly after a sail and engine needed.
2 Strip down starter motor again and give it a good clean up as I may have not done as thorough a job as needed last time.
3 Look at other options - maybe solenoid.
4 Splash out on new starter.

 

[VicS]

Maybe grease soaked into the brushes and is still coming out again.

Definitely dont fork out for a new starter, at least not until you has established beyond doubt that there is something wrong that cannot be fixed.

Did you check the brushes for wear

 

[William_H]

The most likely difficulty is bad contact of the brushes to the commutator. So remove the starter and check that the commutator is clean and bright smooth copper segments.
Next check that the brushes have plenty of pressure on the commutator. As they wear they get shorter and so have less pressure. Make sure the brush holkders are clean so brush can slide easily.
good luck olewill

 

[pcatterall]

Is there no place for vasaline or similar in a starter? ie to ensure the brushes remain free?

 

[duncanmack]

[ QUOTE ]
Is there no place for vasaline or similar in a starter? ie to ensure the brushes remain free?

[/ QUOTE ]

God NO!

Any "wet" lubricant will collect all the dust and crap produced and clog the brushes in the holders.

When I were a lad (!) we were told only to use a dry lube for the inside of starters and for lubricating the spindle for the starter dog to slide on - same reason - oily lube attracts and traps all the crap of the day and prevents the bit that you want to slide freely from doing so.

We see this problem often in the garage!

Modern "dry" PTFE spray might do the trick. Note to self, must try it. /forums/images/graemlins/grin.gif

 

[Jake]

Hi Lescargot

I've got EXACTLY the same problem. Like you, I splashed out on a new Vetus battery, and it solved the problem - briefly.

I'm having the engine out for a makeover, and was told that buying a new starter motor could be 'exhorbitant.' My 4107 is 1969 vintage but - when the starter motor wasn't sluggish, still starts on the button. Touch -and go.

Looking at the wiring, I couldn't help but wonder if the problem was there. It doesn't take much of a loose connection to give you intermittent function, especially with a loose earth wire.

As part of the refit, I'm going for a complete rewire, but I'll have the starter motor off and checked anyway. It could always be a flat spot on the cummutator.

There is a lot to be said for biting the bullet and buying a completely new engine...the Perkin 4107 is really getting on a bit now, but that's another story!

 

[essexboy]

Does the problem go away when the engine is cool ? Starters need some lubricant on the bearings, little but some. I have had this problem when all oil has been removed, the starter gets warm clearances close up and tightens up on the shaft

 

[FlorealIII]

Is the starter earth connected directly to the negative battery terminal ?NOT through the engine block !

 

[l'escargot]

Thanks for all the suggestions, some food for thought there. Looks like head in the engine time again and get the thing out on the bench.

 

[l'escargot]

Well, had the starter out again and more oil/grease was evident on the brushes and commutator, so all stripped down and washed the whole lot in petrol again and left in the sun to dry before reassembling. Fitted back in and all seems ok, firing up several times with no effort. Fingers crossed!

 

[VicS]

[ QUOTE ]
more oil/grease was evident on the brushes

[/ QUOTE ] Any more trouble and I think it would be wise to fit new brushes. It might be wise to fit them anyway cos it'll only let you down when you want to start it. it'll be Ok the rest of the time