Originally Posted by ebisucapt
The contacts in side the solenoid on my 3GM
are not always making contact. Most likely just need some cleaning
. But is there anyway to take it apart? Looks sealed to me. Anyone know different?
This is actually a common problem, especially for cats. What makes you think it's the solenoid that's at fault?
Short between the big positive terminal on the solenoid & the solenoid trigger connection (the wire coming down from the key-switch). You can do it with a screwdriver or a short, stiff piece of wire.
Does it start? If not, then you're probably correct, & you should replace the unit. On our 4JH2E, the starter & solenoid are a single
unit, & the solenoid also throws out the Bendix gear
to engage the teeth on the flywheel. You can get after-market parts that look just like the original, usually for much cheaper, at any good starter/alternator repair shop. We've been using one (bought in Langkawi, Malaysia) for years with no problems.
But if your engine
DOES start by jumping it, the problem is probably low voltage to your solenoid, mostly caused by corrosion
in your wiring
, but also by poor design. Yanmar
, in their infinite wisdom, has a relatively small positive feed wire to the control panel
, & they then run all of the current
for the solenoid through the key-switch, from which it has to get back down to the engine
(a long way on our cat). The accumulated voltage drops are the usual starting problem.
Clean up whatever connections you can find, but the best solution is to buy a little 12v relay from any car-parts shop. These are about a 1"/25mm cube, with 5 spade connectors coming out the bottom. They cost under $10 & the contacts can usually handle 40A (which is gross overkill, but OK).
Wire it down by the starter. The start wire from the key-switch goes to the coil on the relay, with the other coil connection going to any convenient ground. Run a wire from the positive lead on the solenoid to the Common on the relay, & the Normally Open connection goes to the solenoid trigger (where the key-switch used to connect to). The Normally Closed connection is unused.
Now, turning your key to Start will activate the relay, which will in turn activate your solenoid, but the difference is that the solenoid will now get the full 12v, so should throw much more forcefully.