Bukh DV24 Starter motor.

[tt65]

Can any one help.

The starter whirrs but does not engage the flywheel. I cannot contort enough to actually see it whirring. I have checked electrical connections and ensured batteries are fully charged. I can hear the solenoid go and then it whirring sounds.

( I have not checked the battery negative connection to engine block, I forgot)

We had a burst hot water pipe last week that sprayed some hot salt water around the engine compartment, mainly the after area where the electrics are and away from starter motor. I expect the fault to be related but may be coincidence I suppose.

 

[tt65]

I just hate having a dead boat. Cant sleep

 

[oldharry]

The cog that engages the flywheel will stick if it gets at all rusty. It MIGHT just be possible to get it free by by spraying wd40 under the housing - but not very likely. The starter motor needs to come off, and the cog freed off.

The mechanism is arranged so that when the motor starts the cog is thrown forward into engagement against a light spring. The spring pushes it back out of engagement when the starter motor is switched off. If it sticks, it doesnt engage. A common fault.

A badly sticking cog needs to be dismantled which is not so easy, and best left to an starter repair place.

There are two types of starter on these engines. The other is the pre-engaged type where the solenoid pulls a yolk in to engage the flywheel before energising the starter motor. These are more difficult to free off when they stick, which is not often. If you can hear the stater whirring without engaging then yours is not pre-engaged.

 

[Scotty_Tradewind]

oldharry has hit the spot with his advice. My old MGB suffered this and a sharp bash with a wooden mallet used to get it going temporarily. It does need to come off and have a thorough clean though with the finest of lub'. A lot of lub' can pick up dirt on some starter gear as they can be open to the elements and cause the problem, but on a boat engine this is not so likely, rust more the problem.
I've got the same engine but I've not discovered where my starter motor is or what type yet,( too many other things being done), I've played with lots of other bits on it though. For example I discovered where the pencil anode was last weekend. Had to dismantle all the cable shift gear from the quadrant to get a spanner on it. If you do take yours out, make sure you use a socket on it as there is a danger in damaging the head of the plug as it's soft brass.
Good luck
S.

 

[oldharry]

Starter located Stbd side below the alternator, engaging the flywheel a about 10 oclock position. About all you see from the front of the engine is the housing for the engagement mechanism.

 

[tt65]

Thanks

I will take it off the boat and bring it home where I have a vice and bigger hammers than I carry on the boat.

I understand about the anode. I change mine each year, it is usually about 50% eroded.

I also have an MGB and concidentally the starter failed on that a few weeks ago. Wire had come off the solenoid. On balance I would rather work on the Bukh rather than the BL as far access is concerned.

 

[Scotty_Tradewind]

I also have an MGB and concidentally the starter failed on that a few weeks ago. Wire had come off the solenoid. On balance I would rather work on the Bukh rather than the BL as far access is concerned.

Ah the later MGB which tried to defy the American safety laws placed on imported autos. Eventually though the U.S. beat the MG 'small fry' and due to the company heavily relying on the exports it was slowly killed off.

My great uncle Frank Stevens was 'Chief Rate Fixer' at MG's in Abingdon and on the design team that developed the 'A'. He gets a mention here.
http://www.mgcars.org.uk/mgcc/sf/991002.htm
I had a late 1955 TF 1500 for a couple of years when I was 19-20yrs.

Then later on in the early seventies I bought a '65 'B' which eventually had to be rebuilt as the inner skin was rotting from the inside out. It went like a dream though and the early ones were lower slung giving better handling so I was told ?? Best all round fun car I've ever owned. Recently sold my kit car.... a R' V8 beast.... but thats another story.

 

[Csprod]

bringing this one back to the top....

I have a smaller DV10, and am having some odd (intermittent!) problems with the starter AND the stop solenoid.

10% of the time - it starts and stops as normal - no problem
10% of the time - i turn the key and get a the noise of the starter solenoid clicking AND about half a second of starter engagement, stop solenoid WORKS - ALL GOOD !
80% of the time - i turn the key and get ABSOLUTELY NOTHING (no solenoid, nothing), I also get nothing from the stop solenoid.

I have checked all the engine loom wiring/switches and have tried powering the started and solenoid directly with very limited luck (same chances as previously).

I cant imagine the starter AND stop solenoid would fail (and work) simultaneously just by chance... they must be connected some how but i cant work out how !!

Any ideas ??

Thanks,
Craig.

 

[Keith T]

Cspord, you'd be really unlucky to have both fail simultaneously.

Get your multimeter out & Start with the basics:
With your battery switch ‘on’ measure the voltage on pin 30 (white wire) in the back of your ignition switch. This is the main supply to your switch panel, should be 12.8V. If not this would explain you problem.
If that’s ok, then remove the spade terminal from pin 50 (blue wire). This is your start solenoid. Turn the key to position ‘d’ (start). You should now measure 12.8V on pin 50.
Ignition switch back to ‘off’
Now remove spade terminal from pin 58 (connects to your diode plate pin 2) Turn ignition switch to position ‘e’ (stop). You should measure 12.8V on pin 58.
All good? Then check these voltages are appearing at the other end of your cable loom. You can’t unplug your loom to do this – but you can measure them in the back of the milti-pin connector.
If they check out, then check the GND connections on starter motor & stop solenoid
Make sure the heavy batter pos & neg leads are well and truly secure.
If all that checks out then bummer, they did both fail.

 

[VicMallows]

Given your symptoms, the keyswitch sounds the most likely culprit to me. Diagnosing with voltage measurements alone can be confusing because a very likely cause of problem is a high resistance rather than a complete open circuit. My approach would be to first see if the start and stop solenoids function reliably when supplied independently via a temporary (fused) switched supply from the battery. If OK I would then work backwards to locate the fault.

If the keyswitch is the culprit, you will have to decide whether to shell out an-arm-and-a-leg to replace it with an identical switch or whether to simply create your own replacement circuit with -for example- a couple of heavy duty push-switches, one for start and one for stop!

 

[rob2]

Should you need a new ketswitch you might consider a Chinese copy of the Lucas switch, readily available in 3 or 4 position variants on ebay:
http://www.ebay.co.uk/itm/Universal...arParts_SM&hash=item53fb70ef47#ht_2041wt_1170

Rob.

 

[Csprod]

Thanks Kieth and Vic ! I have checked all the engine loom wiring and switching but didnt really consider the high resistance case.... will check it out again.

Thanks for your replies.

 

[Csprod]

Ive noticed that there is no high tension earth coming from the starter or the stop solenoid......

I assume that they earth somehow 'internally' to the engine block.... Is there a possability that they both earth in a common way ?

 

[VicS]

Ive noticed that there is no high tension earth coming from the starter or the stop solenoid......

I assume that they earth somehow 'internally' to the engine block.... Is there a possability that they both earth in a common way ?

Yes both are "earthed" via the engine block. Check the battery negative connection to the block. But the alternator is also earthed in the same way so if it was the negative connection you'd expect charging problems as well perhaps. And the temperature and oil pressure sensors are similarly earthed. Do the warning lights and gauges work OK

Problem with the key switch seems most likely if none of these other things is affected.

Often better to use a bulb on a couple of leads rather than a multimeter for checking. You'll get a normal reading through a bit of resistance with a multimeter but it should stop a bulb lighting properly. Both in parallel is a good refinement; the bulb draws a bit of current and the meter will show if the full volts are not getting through.