WM300 won't start

[Kru Heller]

Hi Guys,
My truck is a 64. It's not very pretty but I have depended on it to help provide wood to heat my house for the past 16 years at least. It has been running fine all season until a couple of weeks ago I tried to start it and at first it just acted difficult, turning over but not catching. It always does that especially when cold and it was cold. But then on the 3rd try - NOTHING! No clicks, no whirrs, NOTHING, no sounds at all. I charged the battery still nothing. The last time this happened I paid a mechanic and he replaced the solenoid. I bought a soilenoid, installed it and still nothing. I replaced the ballast resistor and still nothing. Some Emails for help at another forum got me through testing the ignition key switch which they told me tested fine after I relayed the test results to them. Then I was told to check the two small center posts on the solenoid for continuity and if it is there the solenoid is no good. I took it back and got another but it tests out exactly the same. I'm a semi profecient parts changer but do not mistake myself for a knowledgeable mechanic. Is there someone here that can help me? I want to add that this solenoid comes from Advance Auto and it is a BWD part #S65 if that helps anyone identify that it is indeed the correct solenoid. Thanks!

Kru Heller
Powhatan, Va.

[maineSS]

Have you checked all your grounds? Negative cable from the battery, and any chassis grounds in the starting/ignition circuit. The negative cable from the battery can appear good, but actually be incapable of carrying the current needed to crank a cold engine if corrosion has gotten into it- peel back the insulation at both ends and check for greenish colored material. Will the battery pass a load test? Next thing to check is the starter- you'll have to pull it and have it checked out. If things are good to this point, is the engine locked up so it won't crank?

[Kru Heller]

Re: WM300 won't start

Thanks MaineSS for your reply. I will look closely at the cable from the neg batt terminal but I'm not convinced this is the problem. I did clean off the firewall down to shiny metal to be sure I had a good ground between the bracket of the solenoid and the firewall. The truck has been working well until all of a sudden it would not attempt to turn the starter when it had been turning the starter just seconds earlier. I should have mentioned in the first post that if I jump the starter it does turn over and the engine does turn. I also should have been more clear in my original post that the last time this happened and the mechanic made the house call and replaced the solenoid was years ago, without checking records it was at least a decade ago. I've had this truck for a long time and it has been a good and reliable truck. I'm especially curious about the counsel I got that said the 2 small center posts on the solenoid should not pass a continuity test with a multi-tester and they do. I was told this was the problem with the first replacement solenoid last week. I'm waiting to be sure I have the correct and a working part before putting it in the truck if that is possible. Thanks.

Kru Heller
Powhatan, Va.

[gmharris]

WM300 won't start

I agree with maineSS that it sounds like you have a bad ground. The fact that it will start one moment and not the next is a good indicator of a bad ground. Sometimes, even the best looking connection will have too much resistance and the problem will show itself unexpectedly.

What I do is first to make sure I have a hot battery. Then I turn on the headlights. If the headlights light, have someone watch while you try to start it. If the lights go out or dim significantly when you turn the key, it is probably a bad ground situation.

I'm not sure how your solenoid is designed, but if it has connections for positive and negative leads (I'm talking about the small terminals, not the large terminals) there will be continuity between the terminals that the ignition key is connected to. Some solenoids have another circuit which is designed to pass current only while the solenoid is activated. This is designed to bypass the resistor to the coil and provide full voltage during starting. This (these) connection(s) will not have continuity unless the solenoid is energized.

It's easy enough to check the solenoid. Just check for continuity between the two large terminals when you put a charge to the two small ignition terminals. Usually, you can hear (and feel) the solenoid operate.

There are many more experienced mechanics than I am on the forum. I'm sure they will chime in. But, since you are probably anxious to get on the road again, I thought I would put my two cents in while they organize their thoughts.

[Kru Heller]

WM300 Won't Start - Test results need help

Thanks to GMHarris and MaineSS for replying. I checked all the grounds I know, took them apart, cleaned the connections and applied some dielectric grease. I took the battery out for a load test and it's good. I cannot do the headlight test as recommended because the headlights do not work.
I took a jumper cable and for a few seconds only I connected the +pos post on the battery to the starter and the starter does turn the engine.
I re-did the test light check of the ignition switch. The ignition switch has 4 posts on the back. I've identified them and the results as follows:

ACC post - (multiple wires attached) - the test light lights up when the key is in the ACC position and RUN position but does not light up in the OFF and START positions.

Center post - (orange or faded red wire attached) - the light comes on with the key in the RUN and START positions and goes off in the ACC and OFF positions but is much brighter in the start position.

Power post - (two heavy violet wires attached) The light comes on all the time no matter what position the key is in.

Side post - (heavy red wire attached) - light is off in the OFF and ACC positions and lights up in the RUN and START positions.

Using wires and alligator clips I did a test light on the two small posts on the solenoid and one of them does have power when I turn the key to start and run but there is never power to the solenoid post that connects to the starter.

Now I need some help interpreting this data or instructions about what to test next. I hope there is someone out there ready to take this novice parts changer to the next step in learning about my truck. I'm really stumped and need to get my truck going. Winter is not over, there is no telling when I might need to pull someone out of the ditch in the driveway.

Kru Heller
Powhatan, Va.

[gmharris]

WM300 won't start

O.K. My two cents again: You have eliminated the battery and the starter as a problem. The output from the ignition switch seems right, except that you say the wire to the terminal on the solenoid is hot in both the start and run position. This should only be hot in the start position. Since this would result in the opposite problem, i.e. the starter turning all the time, I suspect this is not actually the case.

Perhaps you have the terminals reversed and are putting voltage to the terminal used to bypass the resistor. Maybe, the new solenoid has the terminals reversed or you just mixed them up.

Also, I would go back to the bad ground possibility, except this time in a different area. You say that power is getting to the solenoid terminal as evidenced by the check light. But that does not show that power is actually going through the solenoid. Since the solenoid activation circuit has only one wire, the solenoid must be grounded through through the bracket. Make sure you have a good ground there.

You can eliminate everything but the solenoid by using the jumper cables to jumper around the two large terminals on the solenoid. Be careful. Since you have already jumpered from the battery to the starter, I assume you can do this without problem.

By the way, I checked the two terminals on my solenoid, there is no continuity between them.

Let us know how you finally fix this.

[712edf]

backup starter

In the meantime if possible do what my grandpa did with his p/u & tractor; always park on a hill:-)

[Kru Heller]

Hi Guys,
Thanks gmharris for replying, I appreciate your help. I'm going to try to ask some questions about your reply by typing my question within your text, I hope this works.

The output from the ignition switch seems right, except that you say the wire to the terminal on the solenoid is hot in both the start and run position. This should only be hot in the start position

I wondered about this when I did the test and was thinking someone would tell me the problem was the switch. I need to emphasize the difference in brightness in the test light. It may not be enough juce to actually turn the starter over. In the RUN position the light has an orange glow but in the START position the light burns brightly.

Maybe, the new solenoid has the terminals reversed or you just mixed them up.

I want to be sure that here you mean the two small posts in the center of the solenoid? I didn't mention everything that I tried today because I didn't know the significance. I checked these two posts and with the key in the RUN position the left (as the truck is oriented with the drivers side on the left) post has power while the other does not. But I was not able to get power to the post connected to the starter. I will try reversing these but I thought the power post was to supply power to the coil and it shouldn't affect the power to the starter side. If I have this wrong please somebody tell me.

the solenoid must be grounded through through the bracket. Make sure you have a good ground there.

That is my understanding too, the solenoid is grounded through the bracket. The old solenoid was held on with two machine screws that went right into the firewall. The new solenoid bracket is too small to align with both holes in the firewall. I used a shiny new screw and buffed the area behind the firewall down to shiny metal then slathered on dielectric grease. I also used a wire with alligator clips to connect to a ground. But I'm still not convinced the ground isn't the problem but have run out of places to look.

You can eliminate everything but the solenoid by using the jumper cables to jumper around the two large terminals on the solenoid. Be careful. Since you have already jumpered from the battery to the starter, I assume you can do this without problem

I'm not sure what you mean. Isn't that the same as connecting the +pos battery terminal to the starter? Do you mean connect the two large terminals on the solenoid? Either way it makes the starter turn.

By the way, I checked the two terminals on my solenoid, there is no continuity between them.

Do you mean the two large terminals or the smaller terminals or some combination? I just went out with a flashlight to check this. There is continuity between the two small terminals. There is no continuity between the large terminals unless I turn the key to start then the buzzer comes on. Does this tell me the problem HAS TO BE A GROUNDING PROBLEM that I just haven't found? I also noticed something that to me is strange. I have the -neg post to the battery disconnected but with the tester in continuity mode when I clip the two main terminals on the solenoid together I get a 12.65 reading!!! HELP - I don't know what that means. I think it tells me the solenoid is grounded.

I have no idea what to do next. The answer may be staring right at me but I just don't have the knowledge to see it.

Kru Heller
Powhatan, Va.

[gmharris]

WM300 won't start

O.K. lets backup. Evidently, I mistakenly assumed you were understanding what I was saying and, maybe, I took too many short cuts in explaining.

Basically, the system you are dealing with is about as simple as they come. That doesn't mean there isn't a glitch that would stump even the most battle hardened veteran.

Really there is only two types of problems that will affect a system like this:

1. Component failures, i.e starter, battery, solenoid and ignition switch problems. And

2. Wiring and connection failures.

You have eliminated the battery and starter. The ignition switch sounds like it is working correctly. That leaves the solenoid.

If you bridge from one big terminal to the other big terminal on the solenoid, the starter should turn. If it does, the solenoid is bad. If it doesn't, the problem is somewhere else since the solenoid is no longer in the circuit.

The advantage of doing it this way over what you did is that bridging the solenoid proves whether the cables up to the starter are in good order. (I still suspect a bad connection)

[gmharris]

WM300 Won't Start

Forgive me from running on, but this might be of interest to you in your trouble shooting tomorrow morning. You seem to be using diaelectric grease rather liberally. Dialectric is another word for insulator. So if you are using this grease between two items that should be in electrical contact (such as the battery terminal), you are probably doing the wrong thing.

From the Moabjeeper website: "Dielectric grease is a thick, non-conductive, water resistant grease. The "correct" use of dielectric grease is to pack the area surrounding an electrical connection with the grease. The grease should be all around, but not actually touching any of the metals that actually make the electrical connection."

On the battery terminal, the best connection is achieved with bare shiny metal. A wire brush is good, but I sometimes just scrape the terminals and post clear to bare shiny metal. Clean metal to metal is the best conductor there is.

One of the best readily available products to seal out corosion on battery terminals is petroleum jelly. In tests by Practical Sailor Magazine, petroleum jelly performed as well as commercial battery products. Although, petroleum jelly may not work so well in the engine compartment of a vehicle where heat is more of a problem.

[Charles Talbert]

The correct solenoid????

Solenoid switches are designed for many varying applications. Some ground via 1 of the small terminals, some ground via the mounting bracket & the small terminals have other purposes. Appearance of the units will be virtually the same. NAPA offers diagrams with their solenoids to determine how they work & what they are designed to do. Be sure you have chosen the correct functioning solenoid for your application.

Also bear in mind cold weather adversely affects these components. Cranking on a day that isn't too cold may go OK, cranking on an extremely cold day may bring about a totally different reaction. Long story short, test results may suggest components are fine, while the severe load application of cranking an extremely cold engine may bring about another result completely. Unless you figure out something shortly, I'd venture to say you will be ahead in the game to call the mechanic who makes house calls again. Throwing $$ at it to replace parts using the trial & error method will get costly really fast. You can easily spend more than the cost of repairing your real problem, yet never touch it.

[gmharris]

Problem Solved

Kru reports that he finally solved the problem. Evidently it was a combination of two problems: a bad replacement solenoid and a wiring problem under the dash.