Intermittent cranking problem on Universal engine solved.

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Dennis

Re: Doesn't disable anything

Post by Dennis »

Thats A GOOD SIGN! maybe it doesn't operate a solonoid like mine does (clicK)Mine is a Westerbeke. I would think they would all work the same. Just want to be cautious when is comes to important things like the engine starting when you need it

Thanks!
M. R. Bober wrote: Dennis,
After I moved the wire, pressing the "glow plug" button moved the ammeter into the deep discharge range. This is, of course, the same as before the wire was moved.

From my quick scan of the schematic, it doesn't appear to matter--electrically--how the starter switch gets its input. There may be other issues related to using both thumbs simultaneously ("One if by land;two if by sea."??). If so, I hope someone will announce them.

In the interim: She starts first time, every time.
Tom

Re: Wiring question

Post by Tom »

Wow this is complicated to do in writing. If we could sit down and draw a picture we could resolve it I'm sure in a matter of minutes. BTW "FWIW" is computer shorthand for "For what it's worth" and BTW is computer shorthand for "By the way" "IMHO" is "In my humble opinion", FYI is "For your information". There's a website that lists a couple hundred of these. But back to the wiring.

I thought you said that when you turn the key on you heard the click. When you press the button that's a different deal because you then are energizing whatever circuit that button is in. If I understand what you are saying it sounds like you think the current is brought to the glow plug switch from the starter switch. I think it's just the reverse. Look at it this way, let's imagine that you disconnect the red wire between the starter switch and the glow plug switch and remove it all together. Would the glow plugs still function? Yes, because the electricity doesn't come from the starter switch. The electricity comes to the glow plug switch from the key switch via the white wire. Removing the red wire to the starter switch wouldn't affect the white wire in any way. When you turn the key on the glow plug switch will have electricity on it via the white wire. When you pressed the glow plug button it would close that circuit and electricity would flow from the battery to the key switch from the key switch (via the white wire) to the glow plug switch through the glow plug switch and down to the glow plugs via the small wire on the other lug of the glow plug switch. Removing the red wire to the starter wouldn't affect this circuit. Of course, if you pressed the starter button now the engine wouldn't turn over because there would be no electricity going to the starter switch but there would still be electricity flowing through the gp switch to the glow plugs.

Now if you want to crank the engine you have to bring electricity to the starter switch. Cape Dory had it wired so that the red wire which brings electricity to the starter switch was attached to the same screw as the wire that runs to the glow plugs. Thus you had to push the gp button before the engine would crank. The change I'm suggesting is to move the red wire that feeds the starter switch to the other screw on the gp switch. That way when you turn the key on it feeds electricity to both the gp switch AND the starter switch at the same time. Thus the glow plugs would still function and the starter would function but only when the key was on and you pressed the appropriate button, however you wouldn't have to press the glow plug button first to bring electricity to the starter switch.

It seems like you were looking at it as if the red wire between the starter switch and the gp switch was bringing electricity FROM the starter switch TO the glow plug switch. The white wire from the key switch brings the electricity to the glow plug switch not the red wire from the starter switch. Thus, removing the red wire from the gp switch doesn't affect the glow plug circuit in any way. That's the way I understand it.

In any case I think we've beat up on the BB enough for an esoteric subject. Email me directly and we can pursue it further if you wish. BTW John Doyle checked it out with a volt meter on his boat. You might want to email him as well.

Regards, Tom

P.S. My engine runs with the key shut off also and it definitely has an electric fuel pump. I guess this is because the engine is below the fuel tank and once you get it running gravity and the pressure from the return line will deliver enough fuel to keep it going. You need the electric fuel pump to bleed the lines of air when the engine isn't running or if you've run the tank dry and you need to prime the filters and lines. After you've changed the fuel filters and there is air in the line so that the engine won't start, how do you get the fuel from down in the tank up to the primary filters if you don't have an electric pump? Surely you don't crank the engine while bleeding the injector pump - or do you? On mine I turn the key on and the electric pump starts pumping, then you crack the bleed screw on the injector pump and the electric pump pushes the air out of the line and delivers fuel to the injector pump. When it's running free of air bubbles you tighten the bleed screw and then the engine will start -- but that's a debate for another day and another thread.

Regards, Tom


Dennis wrote: Tom, We might be comparing apples to oranges. The click is deffinitly
when I push the GP button. I don't have an electrict fuel pump. After I start my engine it will run with the key off. I have to have the key on and push BOTH bottoms at the same time to start the motor. I'm suppose to press and hold the GP for ten seconds, then while keeping the GP button in also push the Start button to start the engine. (on mine)The key feeds voltage to the glow plug button, thru the GP button when its pressed to the start button. (On MINE)If I moved the feed from the input side to the output side of the GP switch, I would no longer feed the GP switch at all and the glow plugs would not operate. Internally the switch is a single throw double pole switch, Which means it switches two circuits with one throw (push) 1st circuit Passes voltage to the starter button. The 2nd makes a connection to the GPs .If you just put a wire strap across those two terminals, (Input & output)it would be the same thing. You would be eliminating the internal working of just one circuit in the switch, but still feed the input side of the switch for the circuit for the glow plugs.
What does FWIW mean?
I just don't want people to make these modifications, and then when they really neeed their motor, it won't start because its cold. Boy! sure hate typing!
Dennis
Tom wrote: I agree with that. FWIW my understanding of the wiring is that the key doesn't energize the starter or glow plug circuit. Turning the key sends current to the upstream side of the glow plug switch. When you press the starter button or the glow plug button, that's when the solenoid is energized on the starter motor or the glow plugs are energized. Electricity comes from the batteries via the mast switch to the key switch on the instrument panel. Turning the key on sends current to the upstream side of the glow plug button, but doesn't energize the glow plugs -- otherwise they would be on all the time the key is on. When you want to energize the glow plugs you press the glow plug button which closes that circuit and starts heating the glow plugs. Once they are warm you let up on the button and that breaks the circuit. The click you hear when you turn the key switch is the electric fuel pump being energized which does not go through any buttons and pumps all the time the key is on. I'm not a mechanic so I'm explaining my thinking so that if I'm wrong you can explain why.

In my diagram the fat white wire brings current from the key switch to the glow plug switch, thus there is current on the glow plug switch regardless of what the starter switch is doing. When you press the glow plug button, current is sent via one of the small wires on the downstream side of the glow plug switch to the glow plugs. As I understand it the glow plugs should work regardless of where the tap to the starter button is made.
Dennis truett wrote: Tom - Per my EMAIL... I received you diagram which showed only the starter circuit. What we need to see is the GLOW plug circuit since that is what the buttom actually does. The GLOW plugs require a lot of current. Because of this the final connection from the battery supply to the GLOW plug in made through a relay.(solinoid) That relay is energised by the glow plug push button. Just like in a car. The ignition key operates a Relay (solinoid) which closes and energises the starter. On my CD you can hear the relay close when the GLOW PLUG button is pushed in. An easy way to determine if you have disabled the glow plug is to listen for this relay to operate. Just because the engine starts, doesn't mean you haven't disalbed the glow plugs. My engine starts easy this time of year, but does require the Glow plug on thoes cold mornings in spring and fall. THis is purly speculation on my part, but better safe than sorry.
Dennis


TomCambria@mindspring.com
Tom

Holy Cow, a Westerbeke?

Post by Tom »

You mean you've been arguing the Universal wiring scheme and you don't even have a Universal??? Westerbeke probably has a completely different wiring scheme and maybe the electricity does come to the glow plug switch from the starter switch on those. You could have told us that up front and saved a whole lot of time. I certainly don't recommend this change for Westerbeke, Volvo, Perkins or Yanmars for heavinsake. This has ONLY to do with the Universal wiring scheme.

Dennis wrote: Thats A GOOD SIGN! maybe it doesn't operate a solonoid like mine does (clicK)Mine is a Westerbeke. I would think they would all work the same. Just want to be cautious when is comes to important things like the engine starting when you need it

Thanks!
M. R. Bober wrote: Dennis,
After I moved the wire, pressing the "glow plug" button moved the ammeter into the deep discharge range. This is, of course, the same as before the wire was moved.

From my quick scan of the schematic, it doesn't appear to matter--electrically--how the starter switch gets its input. There may be other issues related to using both thumbs simultaneously ("One if by land;two if by sea."??). If so, I hope someone will announce them.

In the interim: She starts first time, every time.


TomCambria@mindspring.com
Bill Sonntag

Re: Intermittent cranking problem on Universal engine solved

Post by Bill Sonntag »

Tom: I have not given any thought to the question you raise. I did & do
have a wiring schematic for the panel and the engine but I don't rightly
remember how I rigged it and I just deleted the hazy recollection I typed
out here a few moments ago - I do not want to confuse the issue. I'll be
aboard this weekend and I might have a chance to take a look. However, the
original post does a good job of describing how to do it.

I will say that I can not imagine that current flowing only when the
starter switch and circuit is engaged should be a problem. If current
flows to one pole of the glowplug switch when cranking the engine, it
should not make a difference because the glowplug circuit will not be
closed since the switch will not be pressed with the altered wiring
pattern.

Anyway, its worked great for me for at least three seasons. Nothing was
disabled on the panel or elsewhere with the modification. I'm just sorry I
did not think to post it here when I did it. I'll keep that in mind on
future projects.

Happy Sailing

Bill Sonntag



dalbers1@earthlink.net
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