howto to how to clean starter motor solenoid? MGB GT 1969 UK model

Hi

(I don't know much about cars and have access to a limited amount of tools)

My MGB GT 1969 UK model is having trouble starting. Sometimes it starts straight away and sometimes I have to turn the ignition switch on/off 15 times.

My friend suggested that it might be a faulty starter motor solenoid. He suggested that maybe I take it apart and service the interior. A thread I found here
suggests I check and clean all the wires/contacts http://www.mgexperience.net/phorum/read.php?1,1274617,1274617#msg-1274617

My question is what's the best way to physically get at the solenoid? I don't fancy removing the distributor cap etc. Would it be easier to drive the front end up on two ramps? Or shall I take it to an MG garage?

thanks in advance

I've always attacked it from underneath.

Francis,

with the starter on the bench, you can unsoilder the two connections ot the coil of the solenoid and pull it apart.
You will find the large contact points inside badly burned and eroded. These are the large copper points underneath the bridge of the solenoid core. They are connected to the battery and to the starter motor itself and can be taken out of the cap by undoing the nuts on the outside. Be careful the black plasik cap can brake apart easyly when tightened too much!
File them down to a clear and flat bright surface, smothen them with some sanding paper and reassemble all items again. When finished with the reassembling, resolder the two conections of the coil and the starter will work again on first try,
I did this on two of he starters on my B's and it is not a diffcult job. Takes about one hour with pulling the starter and putting it back to the car.

Hope this helps

Ralph

Hi Francis,

If you want to take apart the starter solenoid that is resident on the starter itself, then the first step is the removal of the starter from the car. This may entail the removal of the plug wires and distributor cap at a minimum and quite possibly the distributor itself depending on clearances in the engine bay (my distributor has always been removed for other reasons when I've had to remove the starter, so I'm guessing a bit, but it would definitely make life easier). You may also want to check, clean and lubricate the rest of the starter action while you've got it out.

Once the starter is out, the solenoid is easy enough to remove from the starter, but you'll need a good soldering iron/gun to desolder one of the wires on the solenoid to take it apart to clean and service. A new solenoid from Moss (Lucas brand not aftermarket) runs about 46 GBP, so you may want to consider this if your solenoid is beyond help. I'll leave it to you to decide if a trip to the garage is warranted not knowing your level mechanical skill. Taking the entire starter to a reputable shop that specialise in starters might be something you would want to consider also.

I hope this helps a bit.

Check the electrical connections in starter circut/including the starter itself before
digging into it.

As Bernard suggests above, I would look at all the electrical connections first as these are much easier to get at. I have had this happen more than once, and each time it has been due to poor battery connections. Start with the battery, remove and clean the connectors and battery posts, then do the same with the main feed to the starter motor, and then both ends of the earth strap between the motor and the body. If any of these connections is loose or corroded, then it won't be able to conduct the high current needed to operate the starter motor. A connection can look firm but still be ineffective due to corrosion within the connection. The earth strap between the motor and body is often overlooked and can even be broken.

I suggest you disconnect the battery first and work on the rest of the connections then clean and reconnect the battery last - that way you won't get any potentially dangerous sparks from an accidential short.

sounds to me like a bad ignition switch more than a starter solinoid if they go out they usually just stop working all togather

At a dealership they would change started if that didnt fix ,,thay would change battery,,then the relay and on and on
BL dealership i worked at going to college..
Service mgr got pissed if he saw you hooking -up the Snap On test stand for any elect problem ..
He got 15 percent of all parts sold plus a percentage of your labor and a salary also,,so
efficency was measured in how many parts/hour was changed.