motor problems

[gonad]

fuelling up for the grand off, go to start motor, just click click from the relay.batteries full. remove and test starter motor fine, clean brushes try on ground again fine refit just clickclick can the wires carring current suddenly die? if the wires have been put back correctly could the polarity have changed? if i change them round will imess the motor up if i try starting it? perkins4108 thanks for any help

 

[castaway]

Hi Gons

I have a 4108 on my Halberdier and the begining of the summer was dominated by electrical probs. Although the engine starts really easy (thank God) I was losing power somwhere.

A friend said it was likly to be an "HR" problem ie. . high resistance in the circuit and I checked and chased all the obvious areas with little sucess It wasnt until the whole thing packed up (off Lulworth of all places) that it became more easy to find as there was no power at all. Turned out to be the ammeter had been quietly melting inside.

Unbolted it and put a bolt thro the connections and threw the ammeter away... problem solved.

Nick

www.yachtsite.co.uk/fairweather

 

[pete]

Is there any reason that the engine cannot turn over ?
could it be water locked ?
try starting handle with decompressors open if applicable
good luck

pete

 

[gonad]

waterlocked? sorry wots that?nocrank handle

 

[PaulJ]

This sounds a bit like a problem I had with a car some years back which turned out to be caused by muck/high resistance/poor contact in the connections to the main battery terminals. Everything else worked OK but it just couldn't cope with the current required to turn the engine over..... I just cleaned the terminals and connectors and all was well. 'Hope your problem is as simple as that!

 

[yoda]

Put some very rough emery to your battery terminals and all connections. Battery terminals should be a shiny lead colout not a dull grey

Yoda

 

[brianrunyard]

Waterlocked or "hydraulic lock" is when water has entered a cylinder, possibly sucked back from the exhaust, and prevents the engine turning over, because liquids can't be compressed.

Brian
http://homepage.ntlworld.com/brunyard

 

[chas]

Had a similar problem. Try tighening the battery terminals

 

[Avocet]

Just taking your starter off and putting it back might temporarily cure the problem. Next time it does it, try tapping it with a hammer (if you can reach it). If you can't try a piece of steel tube (and a hammer) to reach it in situ. Starters can fail because the brushes are sticking in their housings or because the solenoid is sticking and (frustratingly) they can work fine again for a while when disturbed! If it starts when you've hit it, get the starter re-built. Go to an auto-electrician first, they haven't learned how to charge "marine" prices yet! I got my BMW D12 starter "overhauled" (basically new brushes and a clean I think) for £12 a few years ago!

If hitting the starter doesn't help, have a good look at the earth strap. Somewhere, there will be a big heavy electrical wire that takes the return current from the engine back to the battery. It's just as important to clean these terminals as it is to clean the battery terminals.

 

[vyv_cox]

Bosch pre-engaged starter motors

have an unexplained tendency to do something like this. I know of at least four VW caravanettes that have this problem occasionally. I have worked on a Westerly with a 3-cylinder Volvo that had this identical problem. My Bukh had the same starter motor (but not the problem) and I know that many Volvos use this starter.

If that's what you have try this. Take a direct connect, I usually use a screwdriver, between the live incomer and the starter connector terminal. It sparks a bit but may well solve your problem. Answer is to run an extra wire from the starter terminal to somewhere near the battery. If the problem recurs, just touch the end of the wire on the live battery terminal.

 

[oldharry]

Re: Bosch pre-engaged starter motors

I too have met the mystery Bosch starters. A quick way to check connections is to soak them with WD40, which will often provide a 'quick fix'. Unfortunately once the WD dries off (which it does quickly if the terminal still gets warm) it fails again, but it saves chasing round undoing and scraping terminals to find the culprit! Also gets you going in an - er - embarrasing situation!

Another way is to check each component and connection in the starter circuit (negative returns as well) for heat after a failed start. But be careful - things may get very hot very quickly!

 

[vyv_cox]

Re: Bosch pre-engaged starter motors

I have stripped starter motors to the last nut and bolt, cleaned and resurfaced everything, and yet they still performed in the same way. The fact that it starts perfectly indicates the starter motor to be OK. It seems, at least for VWs, that the problem is some sort of resistance in the wiring to the starter relay. I have never been able to detect this with a meter, though. Very mysterious.

 

[gonad]

thanks all
took starter to pieces and found commutator burnt out having it put back together again tomorrow and hope to leave manana whoops perhaps not with that forecast!

 

[Chris_Robb]

I had this problem intermittantly on a Perkins - turned out that the brushes were warn and occaisionally the starter stopped in a bit of dead area. - highly technical! Before I found this out I had bought a new battery - which didn't solve the problem. No problems since replaced. Reconditioned units can be got from a place near Chichester - PM me if you need to know - i'll look up the invoice to night.