Sealant for my starter motor

pcatterall

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My motor has just failed. I have put the spare on and noted that the original had drops of moisture inside the casing. I suspect that a hose above has been dripping right onto the join.
I guess that I should have used some blue gasket seal, is this normal practice.
The faulty unit was spinning but not with the power to engage. I expect that when I open it up later I will find some sort of moisture issue. Are there any tips on cleaning and drying and would moisture account for it spinning but not engaging?
If I get it all cleaned out my next task I guess, will be to refit the original so the spare becomes a spare again. At that stage I plan to use blue sealant unless you advise differently. Then look for the dam drip!!
Thanks all!
 
Most starters now have a separate solenoid that engages the starter gear with the flywheel. If your old starter was spinning but not engaging, the solenoid is a likely culprit, though corrosion where the gear should slid could also do it. When fixing the dodgy starter, my first step would be to give it a good wash with fresh water and leave it to dry on a radiator for a few days

There shouldn't be any need for sealant, I reckon your time & beer tokens would be better spent fixing the leak.
 
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Most starters now have a separate solenoid that engages the starter gear with the flywheel. If your old starter was spinning but not engaging, the solenoid is a likely culprit, though corrosion where the gear should slid could also do it.

Olde Worlde starters did indeed have a bendix that required the motor to spin fast for it to engage into the ring gear, modern starters are "pre-engaged". The older starter could spin but not engage, due to not turning fast enough or corrosion. But pre-engaged starters can't spin without engaging, the solenoid must first engage the pinion, the it makes a pair of contacts at the end of its travel, so it can't be a solenoid issue with these starters.
 
Olde Worlde starters did indeed have a bendix that required the motor to spin fast for it to engage into the ring gear, modern starters are "pre-engaged". The older starter could spin but not engage, due to not turning fast enough or corrosion. But pre-engaged starters can't spin without engaging, the solenoid must first engage the pinion, the it makes a pair of contacts at the end of its travel, so it can't be a solenoid issue with these starters.

It is possible that the OP's engine does have an "olde worlde" inertia type of starter. The workshop manual shows both inertia and pre engage types.

If it is an inertia starter then sticky bendix, low state of charge of the battery, bad connections and poor solenoid contacts are all possibl,ecauses of the problem
 
It is possible that the OP's engine does have an "olde worlde" inertia type of starter. The workshop manual shows both inertia and pre engage types.

If it is an inertia starter then sticky bendix, low state of charge of the battery, bad connections and poor solenoid contacts are all possibl,ecauses of the problem

Yes, of course.

I was replying to "Most starters now have a separate solenoid that engages the starter gear with the flywheel. If your old starter was spinning but not engaging, the solenoid is a likely culprit".

If it's pre-engaged it cannot spin unless it's engaged.
 
Thanks all. It is the old type
My first action was to check all the connection, nothing bad spotted but all cleaned and vasalined any way.
Then my check across the solenoid ( don't ask!!) Still just spinning.
Having a spare starter to hand I decided to change it.
Spare starter worked fine so solenoid and connections and battery ruled out.
The original is now on the saloon table ( well padded dear, in case you are reading this!!)
The outer bit with the spinning teeth did not look bad though there was evidence of a bit of water and cleaning with wd 40 and a wipe off means the toothed bit fly's up the spindle with just the force of the little light spring.
Inside there was a little moisture evident but things looked reasonable, I just did the usual clean and a wipe with solvent. The brushes looked fine.
I am searching for a drip but nothing found to date.
My concern is that I found nothing really significant in the starter but I plan to re install it to be sure it is ok and that we have a known to be good spare again.
Thanks for all the usual sound advice.
 
My guess is that the spline drive (bendix) had stuck so allowing the motor to spin but not engage. My guess is that with the application of WD and a bit of exercising it has come free. I think you will find it works fine now if you refit it. However dismantle the drive and clean and lubricate the spline to avoid a recurrence of failure. Yes moisture can cause corrosion and sticking however normal boat atmosphere moisture is usually not a problem with lubrication. olewill
 
Thanks all and yes the failed starter is refitted and working. Only puzzle was that I didn't seem to find anything significantly gungy!! Yes I cleaned the splines, the brushes and the commutator(?) But nothing seemed like it would have been a show stopper!
Anyway back and working. Thanks again!
 
I've not had a Bendix type starter for years but seem to recall that it was not recommended to lubricate the splines at all as it could attract contaminates such as dust (not that there's much dust on a boat).
 
I've not had a Bendix type starter for years but seem to recall that it was not recommended to lubricate the splines at all as it could attract contaminates such as dust (not that there's much dust on a boat).

You recall correctly, oil spins off and just makes a mess, grease actually makes it stickier and will attract dirt. Only thing to put on it is some dry PTFE spray, or nothing.
 
You recall correctly, oil spins off and just makes a mess, grease actually makes it stickier and will attract dirt. Only thing to put on it is some dry PTFE spray, or nothing.

Well, I beg to differ after 40 years of lubricating Bendix drives. The advice to run them dry is certainly true on road vehicles because clutch dust fills the bellhousing and clogs the bendix, but on a sailing auxiliary, there is no clutch and rust is the enemy from damp and lack of use. A smear of any grease is better than nothing.
 
That makes sense.
Well, I beg to differ after 40 years of lubricating Bendix drives. The advice to run them dry is certainly true on road vehicles because clutch dust fills the bellhousing and clogs the bendix, but on a sailing auxiliary, there is no clutch and rust is the enemy from damp and lack of use. A smear of any grease is better than nothing.
 
It is possible that the OP's engine does have an "olde worlde" inertia type of starter. The workshop manual shows both inertia and pre engage types.

If it is an inertia starter then sticky bendix, low state of charge of the battery, bad connections and poor solenoid contacts are all possibl,ecauses of the problem

Olde worlde solenoids also respond to an olde worlde solution; a sharp tap with a hammer!
 
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