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starter motor problems

Posted: 09 May 2015, 16:56
by acw
Hi Everybody
after searching the wiki and the haynes manual i am still stuck
starter motor wont turn the engine over, all i get is a clunk, it has been geting worse over the last few weeks.
it started as a slow grinding and then it would pick up speed and turn the engin over fast enough to start. usual cause is reported as the nose bearing
last week it would just get going so i have replaced the starter motor and its nose bearing.
still the same- clunk no start, it turned over slowly once just enough to kick it into life.
jump started from the car battery - still the same
replaced the battery - still the same.
replaced the crimp connector to the main starter wire - still the same.
fitted a bridging wire from the starter + to the battery + still the same.
moved the bridging wire on to the battery - to the starter body still the same
cleaned the earth strap fittings on the gearbox to body and the battery to body points - still the same
connected a dvm to the starter body and starter + post 12.5v then about 11.5 when i try to start the engine, if i had a poor connection i would expectthe voltage to fall right down.

could the engine be buggered - its an air colled so it cant be a hydraulic lock from a leaking head gasket.

out of ideas
any clues, help

please

Andy

Re: starter motor problems

Posted: 09 May 2015, 17:11
by itchyfeet
Bush in the bell housing could be knackered, it is the second bearing, if gone the motor won't turn properly, common fault.

try turning the engine over manually just to be sure it turns ok

Re: starter motor problems

Posted: 09 May 2015, 19:19
by acw
Hi All
just had a go starting it with the plugs out and still the same
time for bed - or some strong drink

Andy

Re: starter motor problems

Posted: 09 May 2015, 19:33
by itchyfeet
Sorry just spotted you said you changed the 'nose bearing'

can you turn it over by hand with plugs out?

next thing I'd do is to connect a known good battery with jump leads direct to starter, need to be careful but rules out wiring which can be hard to test because the starter draws such high current.

Re: starter motor problems

Posted: 09 May 2015, 20:53
by acw
Hi
think i may have the solution
2nd nose bearing, the one i replaced was the same as the one i removed, but the one supplied with the starter is a wee bit smaller.
perhaps the problem has always been that the nose bearing is a tad to tight causing the slow starting, the replacement i got last year to fix the problem was from JK and was for a 2l air cooled engine. never fitted it as the old one wouldnt come out.
got it out today and it was the same size as the jk replacement.

Andy

Re: starter motor problems

Posted: 10 May 2015, 07:27
by itchyfeet
Usually too loose on the inner diameter is the problem,
jk are not known for their high quality parts, I'd get parts from Brickwerks or vwheratige in future.

Sorry can't really understand what you did from what you wrote but alwats test the bearing on the shaft before fitting.

Re: starter motor problems

Posted: 10 May 2015, 10:58
by acw
well this morning i replacd the bellhouse bearing - again- no different.
tried connecting a battery directly across the starter terminal and the starter body - still no different.

i tried turning the engine over by hand, by putting a socket on the fan centre nut, and it will turn over.
asked my wife to try it and when it is started the fan moves slowly round.

could something in the engine is buggered. any ideas?

or is it that the starter just hasnt got the power to turn the engine over?

am i missing something

cheers

andy

Re: starter motor problems

Posted: 10 May 2015, 11:57
by CovKid
Remove starter, pop the end off the starter (two small screws, two large, a 'c' clip and a washer) and see how much is left of the brushes) - there may not be enough left to get a proper spin. Can be replaced if you have a gas soldering iron for about £7:

https://www.youtube.com/watch?v=gNKSeAAd3rk" onclick="window.open(this.href);return false;

If battery is known to be in excellent order and state of cable and connections also known to be good, a gradual deterioration could well be worn brushes. Could also be a weakened or deteriorating braided wire as per video.

I've said this before, but way too many starters get swapped for recons because owner lacks the skills or inclination to find the fault. Its worth nosing in there. Sometimes a good clean alone is enough - they get full of carbon dust over time.

Re: starter motor problems

Posted: 10 May 2015, 12:07
by itchyfeet
He said new starter fitted so I woukd expect new brushes

Re: starter motor problems

Posted: 10 May 2015, 12:09
by acw
Thanks Covkid
i watched your video on brush replacement and decided rather than do that i would fit a brand new starter
didn't work -still wont turn over fast enough to start.
i am out of ideas for now, even putting a charged battery directly onto the brand new starter body and + post didn't make any difference.

checked and cleaned earth straps bypassed all the power connections, new battery, new starter, 2 bell house bearings fitted.

turned the engine over by hand, no expert, but it seemed to turn ok

given up for now- any ideas very welcome

cheers

Andy

Re: starter motor problems

Posted: 10 May 2015, 12:10
by itchyfeet
Do you have anybodg that could give you a tow to do a bump start to see if
if engine starts and runs ok?

Re: starter motor problems

Posted: 10 May 2015, 12:13
by Oldiebut goodie
Is it any easier if you have your foot down on the clutch when starting/trying to start?

Re: starter motor problems

Posted: 10 May 2015, 13:12
by acw
Hi
Tried everything, clutch in - out no difference, in gear clutch in, out of gear clutch out, nothing.
engine is great at starting - if it turns over fast enough, that is at normal cranking speed.
trouble is it would turn over slowly - then a bit quicker and fire first time, just cant get the new or old starter to turn the engine over fast enough to fire

is it something hidden that i am missing - i doubt i have a faulty starter and a faulty replacement, or have i
any way to test the starter


cheers

Andy

Re: starter motor problems

Posted: 11 May 2015, 20:13
by itchyfeet
acw wrote: connected a dvm to the starter body and starter + post 12.5v then about 11.5 when i try to start the engine, if i had a poor connection i would expectthe voltage to fall right down

Maybe it is electrical, if you have a good connection you get more current so more voltdrop I think, 1v when cranking doesn't sound enough to me.

Have you tried batt and jumpleads both + and - direct to starter and jumping the main 12v starter bolt to the trigger connection?

Can't test the starter out of bellhousing, where ars you? Maybe somebody local has a spare gearbox you could try it in?

Re: starter motor problems

Posted: 11 May 2015, 20:42
by acw
. Hi
taking a break and pondering the problem.

next test is to measure the voltage when cranking over at both the battery and starter terminals.

if they are the same cables ok - starter is faulty as long as the battery voltage stays healthy.

if they are more than 2v drop i will replace them anyway.

still cant explain why when i attached a charged battery directly to the starter terminals it was the same, very slow crank.

must be a faulty new starter - or the engine is seized

thanks for the support and advice, it helps to get any idea or different angle on a problem as sometimes you can get sucked into an idea that is completely the wrong way

Andy