Banging on starter?

[massnspace]

Sailboat would not start yesterday. Older marine diesel.

Took a small hammer, banged on the starter, then it turned over and started no problems.

I had read about that trick and yes, it did work, but why? And will it happen again? What is the long-term fix???

[rslifkin]

Generally that means the solenoid or another moving part is sticking. So it's time for a starter rebuild or replacement, as it's likely to get worse and then eventually fail entirely.

[massnspace]

Originally Posted by rslifkin

Generally that means the solenoid or another moving part is sticking. So it's time for a starter rebuild or replacement, as it's likely to get worse and then eventually fail entirely.

Thanks, and I was afraid of that….

But the good news is that I can buy a brand new starter off eBay for $88 shipped. That is one of the good things about these old engines…..parts dirt cheap…..

[Kettlewell]

Wait! Before you go for a starter rebuild check and clean all the connections between the starter and the battery. A little bit of corrosion can reduce the current enough to cause the starter to fail because it stopped in just the wrong position. Banging the starter might get it to spin, but the problem could instead be corrosion.

[thomm225]

Originally Posted by Kettlewell

Wait! Before you go for a starter rebuild check and clean all the connections between the starter and the battery. A little bit of corrosion can reduce the current enough to cause the starter to fail because it stopped in just the wrong position. Banging the starter might get it to spin, but the problem could instead be corrosion.

No, it's the starter.

Banging on the starter doesn't fix connections between the starter and the battery.

It would be a very small percent chance there was a bad connection at the starter.

Banging on the starter due to worn brushes is a normal fix most all of us back yard mechanics know.

Replace the starter.

The OP may have also noticed the starter turning more slowly over the last few months.

[JimsCAL]

Just be aware that many of the those cheap starters on ebay and Amazon are Chinese knockoffs with a less than stellar reliability record. One common issue is poor castings that crack easily. A rebuild at local starter and alternator shop will be a better option and probably cost significantly less than a new marine one.

[massnspace]

I think the person who said banging on the starter fixing it proves it is a faulty starter is correct. Corroded wiring would not really be fixed by banging, I think….

But….

The starter WAS working perfectly last time it was used. Was not running slowly or any other signs of illness…


I understand that the eBay starters are probably not as good as the original, but I cannot even source an original online. Anything I find is either a cheap knock off or made by some other company not related to my engine manufacturer. For $88 shipped, I think I will take the risk.

By the way, the motor in question is a Universal M-40, which is I think the same as teh Kubota 5432 tractor engine. I found an old M-40 parts manual, but it seems to list every other part except the starter.

Any input into what it would cost to either get an original (good quality) starter, or a rebuild, would be appreciated. And as far as rebuild cost, please bear in mind I live in a city where a 16 ounce latte is $7, and a pint of microbrew beer is $8-$9.

David
Seattle

[JimsCAL]

Pretty sure 5432 is the original Universal diesel model of your engine, not the Kubota engine or tractor number. Those original diesels that came out in the early 80s were 5411, 5416, 5424, and 5432 with the last two digits indicating the horsepower. Their replacements were models like M15, etc. Kubota engines will have models like Z500 which should be stamped on the dipstick. If you can determine the Kubota engine model or the tractor model it was used on, you can probably get a starter at a Kubota dealer at a reasonable price.

[CaptTom]

As for rebuild cost, ask around at the marina or any auto mechanic. There will be a local rebuild shop (or two) which everyone uses. Chances are good that it won't cost much more than the new Chinese one, and in the end you will have a much more reliable starter.

[deblen]

Caution re banging on starter.
Yes-it worked great for me many times going back to '60s.
However,I found out the hard way,with a ?'90s gas vehicle that the old style field windings have been replaced with epoxied permanent magnet motors in newer road vehicles.Tapping lightly with a hammer is enough to shatter the magnets on these new cheap motors.
Not sure if they have hit the boat diesel market yet,but I think some of the "new" inexpensive ebay china motors may be permanent magnet.
5? yrs ago I replaced the orig.Hitachi on my 84 Volvo Penta 2003 with a $130 from DB Elec. on ebay. It spins the motor faster & has worked flawlessly since. YMMV I also had the broken alum. snout rewelded onto the orig Hitachi & it works fine as a spare. If I hadn't been able to repair the orig. I would have bought a second DB Elec. $130 unit as a spare.
Various places wanted >$800USD/$1200Cdn for anything approaching new original.
Same story with alternators.
Cheers/Len

[boatpoker]

Originally Posted by massnspace

I think the person who said banging on the starter fixing it proves it is a faulty starter is correct. Corroded wiring would not really be fixed by banging, I think….

But….

The starter WAS working perfectly last time it was used. Was not running slowly or any other signs of illness…


I understand that the eBay starters are probably not as good as the original, but I cannot even source an original online. Anything I find is either a cheap knock off or made by some other company not related to my engine manufacturer. For $88 shipped, I think I will take the risk.

By the way, the motor in question is a Universal M-40, which is I think the same as teh Kubota 5432 tractor engine. I found an old M-40 parts manual, but it seems to list every other part except the starter.

Any input into what it would cost to either get an original (good quality) starter, or a rebuild, would be appreciated. And as far as rebuild cost, please bear in mind I live in a city where a 16 ounce latte is $7, and a pint of microbrew beer is $8-$9.

David
Seattle

I think you'll find that Bosch starters and many you'll find on Kubota engines were also built in China.

[rls8r]

Banging on a starter (or solenoid) can (temporarily) fix a number of potential problems. rlsifkin (in Comment #2) mentions things sticking. Thomm225 (in Comment #5) mentions brushes. I'd encourage you to check a few things before buying a new starter.

Potential sticking things could be the pinion gear sliding along the shaft to engage with the ring gear on the flywheel. Or - the pinion gear could be sticking to the ring gear on the flywheel. When that happens the starter motor doesn't develop enough torque to turn the engine (it has to have a 'running start' for the planetary gears to develop enough torque to turn the engine). Tapping the starter could release the pinion gear. So - you may want to clean and lubricate the pinion shaft, the pinion gear and the ring gear. Also check to make sure that the bolts that attach the starter to the bell housing are tight and that the starter is aligned properly.

Brushes may be worn (as Thomm225 says), but also consider that they are held against the commutator by small springs. If the springs are weak or if the channels that hold the brushes are dirty, then there may insufficient contact. Tapping the starter could release the brushes - improving the contact. Clean the springs and channels and (perhaps) replace the brushes.

You may find that a simple cleaning and minor maintenance will address your problem. I'd at least try these things before buying a new starter.

[Jammer]

Originally Posted by massnspace

I had read about that trick and yes, it did work, but why?

It worked because the starter pinion is sticking on the starter motor shaft. Tapping it will get it loose if it isn't too badly stuck.

And will it happen again? What is the long-term fix???

Usually the problem gradually gets worse both in terms of frequency of occurrence and in how much pounding is necessary to get the pinion loose.

There are several choices for a long-term fix depending on your situation, your location, and what sort of time horizon is "long term" to you.

The official answer from the engine manufacturer is generally going to be to replace the starter as an assembly, including the solenoid (assuming that your starter doesn't have a Bendix drive which for the most part isn't used any more).

You could just replace the solenoid. Sometimes they get weak over time due to shorted turns. It might help.

You could try cleaning and lubricating the pinion and the slide mechanism for it. It is hard to do a thorough job without disassembly, which may require a press, but sometimes a thorough job isn't necessary.

You can have your starter rebuilt or repaired by a place that does that. A thorough rebuild will involve new bearings, a new solenoid, a new pinion, and new soft parts like snap rings and roll pins, as well as a thorough check of the armature and field coils and new brushes. If rebuild service is available you may find that it is worth having all that done as long as you have the starter off the engine.

As noted upthread, some of the inexpensive service-grade new and rebuilt starters that are on the market are not made to high standards. The difference in useful life can be considerable.

[massnspace]

Well I pulled the trigger and just bought a new one. $88 shipped. I will try to post an update when it goes in….

I don’t know about other parts of the country, but it seems here in Seattle even getting someone to look at something like his is very hard….no one calls back, and even if I could find someone, I am guessing the cost of a rebuild will be extreme. Even if the Chinese one craps out after a few years I’ll be happy with that….for $88.

[Calaban-Alleria]

Originally Posted by massnspace

I don’t know about other parts of the country, but it seems here in Seattle even getting someone to look at something like his is very hard….no one calls back, and even if I could find someone, I am guessing the cost of a rebuild will be extreme. Even if the Chinese one craps out after a few years I’ll be happy with that….for $88.

Personally I would probably pursue the rebuild anyway. There are lots of shops that specialize in that sort of work. Look em up, drive around.
That way you have a new one and a spare - always a good thing - guarantees you will never be in a situation where you need it