I have a starting issue with my 360. Sometimes it starts no problem other times I Hear a click, I rotate the key a few times and it usually starts. Took the starter off solenoid and the starter are brand new apparently. The has to be a starter relay in the circuit somewhere or it is the ignition switch? Would really like a wiring diagram. I have 25 volts at the batteries and at the starter, when the switch wire gets power to the solenoid it fire right up no matter temperature. A good repair manual forth whole machine would be fantastic, if someone knows where I can buy a good one?
Good day Not to sure which machine you have Cummins or Volvo? Kind regards Uffex
M11 cummins
Good day Chester Please see attched Kind regards Uffex
Thank-you that is everything I need, I chased wires. My starter relay is original, I'll pick one up next week see if that solves my problem. if not it will have to be the ignition switch. Put the starter back in today it went back in better than it came out.
Good day Chester I suggest you remove and clean tthe ground connections to engine and cahssis, often the ground gets overlooked. Kind regards Uffex
An often overlooked fault is the alternator D+ or sometimes R wire. In some models it provides a ground for the start relay.
I cleaned up all of the grounds I have found, cleaned up the connections on the starter relay and the battery relay. It is starting a lot more constantly but not 100%. I will clean up the alternator connections. I still think I have an intermittent problem with one of the 2 relays. They are both over $500 from the dealer. So I want to get the right one. the Battery relay is the one making all the noise when it won't start.
Noise? Clicking, knocking, buzzing? Please describe what you're up against.
Good day I suggest, when you crank the motor, have the lamps turned on and see if they dim. Kind regards Uffex
the battery relay is clicking, the starter relay makes no sound at all. When the engine does start the battery relay does not make a sound or at least I can't hear it. the click may be muffled by the engine rolling over. The lights do not dim I have a constant 24.9 - 25.2 volts at the starter, and all of the relays. Not sure how to bench test these relays to see if they are working. I am thinking of wiring in a ford 3 pin relay to see if battery relay still fails. If it starts 100% of the time then it would be the starter relay. If there is a failure it would be the battery relay. The only thing I don't like about that is I won't have safety for over run.
Hey thanks for all the help by the way I really do appreciate it.
Yeah. You're going to want to avoid wiring in things that don't belong. Volvos are loaded with diode and resistor suppressed relays. The computers rely on those diodes and resistors to protect them from voltage spikes resulting from field collapse. You're going to want to post your serial as well as a pic of your instrument panel. I or one of the other knowledgeable guys with the info, will post up the next step.
If your rectifier (diode trio) whatever you wanna call it, is crapping out, that would explain an intermittent start. Measure for voltage at the skinny wire going to your alternator, should be yellow iirc and should be less than 10 volts key on, engine off. Running voltage should be approximately 24v and the hourmeter should be running.
Good day The main relay see attched has a diode indide may be worth a check olomg with the contacts, this relay is a very common all products component if you need one it may be worth cheching outt different source. In regard to "over run" protection was not a feature of past machines, as you are cautiouse I do not believe you will over crank. I guess you have checked out the Isolator switch & terminals Kind regards Uffex
Sorry if it is information overload see attached. Kind regards Uffex
If you have removed the tin work above and behind the batteries, you see the 3 relays. The one posted above (the flying saucer) is the safety relay, the black rectangular box is the pre-heat relay and last, the cylinder one is the starter relay. Flanked in between are 2 black or blue plugs about the size of your fingertip. Those are diodes. If you've got a diode test function on your voltmeter, verify that they aren't open both ways or shorted both ways. Additionally, if you follow the front of the tank, immediately behind batteries, up you'll find more harness leading to a relay box. That box holds 7 or 8 relays. 2 are critical to ECU boot-up. Suggest, for testing, swap EMS & DATA w/ horn and A/C or high speed travel. Mark relays first so you remember. Good luck
Uffex, I looked at that diode yesterday, but if diode goes I don't believe it will intermittently work, corrosion inside the battery relay was only the top cover, the movie parts and coil were clean. it would be easier to find if was 100% fail. resistant across the battery relay, key off and key on seems to be okay. I'll go through that troubleshooting guide. I have done a fair bit of it now checking voltage and just cleaning connections. Voltage everywhere has been right around 25 volts. When I started everything was 24.5 volts funwithfuel I will have a look for those relays today see possible they or wiring are the issue too. thank-you a lot guys have a good day
Beneath the relay housing, is about 5 oblong electrical connections. They like to trap water and promote corrosion. You might have to remove the battery box housing for better access.