Forums

Truck Starter/solenoid/battery help

Started by amdx September 25, 2014
 >   I'm having very intermittent lack of starter rotation on a Toyota
 > T-100. Over the last 14 years I have replaced the contacts in the
 > solenoid and more recently (1 to 2 years) replaced the starter.
 >    For trouble shooting I have a meter with one lead connected to the
 > bolt on the solenoid and the other to the frame. (solenoid is built 
into the starter)

 >  The plan is; if I can get it to malfunction while trying to start it
 > and the voltage on the solenoid is 12.7v vs 10.7 then I know the
 > solenoid contacts didn't connect (if they clicked) or the starter is
 > open (less likely).
 >   If the solenoid clicks and the voltage drops to a low value then I
 > probably have a bad connection in the wiring.
 >
 > So far I have engaged the starter 25 times without malfunction.
 > Letting things cool, then I'll try again, if I hit 100 my work is 
 >done for this go round!

 >                             Mikek
 >


   Ok, after about ten more times
  switching the key to start, the starter did NOT engage. and the 
voltage stayed at 11.9v VS 10.7 when the starter engaged.

  So by my logic I suspect the contacts in the solenoid.

Anyone have other thoughts and a way to differentiate.
Oh, I like that going for a differential diagnoses!

                                  Mikek

PS. I lament selling my Simpson 260, I had to grab a panel meter and 
adjust it from a 75 volt meter to a 15 volt meter. Digital meters are
not real helpful for this type of testing.
On 9/25/2014 11:56 AM, amdx wrote:
> > > I'm having very intermittent lack of starter rotation on a Toyota > > T-100. Over the last 14 years I have replaced the contacts in the > > solenoid and more recently (1 to 2 years) replaced the starter. > > For trouble shooting I have a meter with one lead connected to the > > bolt on the solenoid and the other to the frame. (solenoid is built > into the starter) > > > The plan is; if I can get it to malfunction while trying to start it > > and the voltage on the solenoid is 12.7v vs 10.7 then I know the > > solenoid contacts didn't connect (if they clicked) or the starter is > > open (less likely). > > If the solenoid clicks and the voltage drops to a low value then I > > probably have a bad connection in the wiring. > > > > So far I have engaged the starter 25 times without malfunction. > > Letting things cool, then I'll try again, if I hit 100 my work is > >done for this go round! > > > Mikek > > > > > Ok, after about ten more times > switching the key to start, the starter did NOT engage. and the > voltage stayed at 11.9v VS 10.7 when the starter engaged. > > So by my logic I suspect the contacts in the solenoid. > > Anyone have other thoughts and a way to differentiate. > Oh, I like that going for a differential diagnoses! > > Mikek > > PS. I lament selling my Simpson 260, I had to grab a panel meter and > adjust it from a 75 volt meter to a 15 volt meter. Digital meters are > not real helpful for this type of testing.
My Fluke meter has a bar graph at the bottom to give you some insight to what is going on when the digits aren't clear. I have a T100 and had the same solenoid contact problem which I repaired. Actually I should be due for them to go bad again, it's on 206 kmi now. I don't think you can say which is bad as yet. All you know is there is an intermittent open between the point you are measuring along the path to the battery through ground. But given the known issue with the solenoid, I would suspect the contacts. How many miles since you replaced the contacts or the whole starter? -- Rick
On 9/25/2014 11:56 AM, rickman wrote:
> On 9/25/2014 11:56 AM, amdx wrote: >> >> > I'm having very intermittent lack of starter rotation on a Toyota >> > T-100. Over the last 14 years I have replaced the contacts in the >> > solenoid and more recently (1 to 2 years) replaced the starter. >> > For trouble shooting I have a meter with one lead connected to the >> > bolt on the solenoid and the other to the frame. (solenoid is built >> into the starter) >> >> > The plan is; if I can get it to malfunction while trying to start it >> > and the voltage on the solenoid is 12.7v vs 10.7 then I know the >> > solenoid contacts didn't connect (if they clicked) or the starter is >> > open (less likely). >> > If the solenoid clicks and the voltage drops to a low value then I >> > probably have a bad connection in the wiring. >> > >> > So far I have engaged the starter 25 times without malfunction. >> > Letting things cool, then I'll try again, if I hit 100 my work is >> >done for this go round! >> >> > Mikek >> > >> >> >> Ok, after about ten more times >> switching the key to start, the starter did NOT engage. and the >> voltage stayed at 11.9v VS 10.7 when the starter engaged. >> >> So by my logic I suspect the contacts in the solenoid. >> >> Anyone have other thoughts and a way to differentiate. >> Oh, I like that going for a differential diagnoses! >> >> Mikek >> >> PS. I lament selling my Simpson 260, I had to grab a panel meter and >> adjust it from a 75 volt meter to a 15 volt meter. Digital meters are >> not real helpful for this type of testing. > > My Fluke meter has a bar graph at the bottom to give you some insight to > what is going on when the digits aren't clear. > > I have a T100 and had the same solenoid contact problem which I > repaired. Actually I should be due for them to go bad again, it's on > 206 kmi now. > > I don't think you can say which is bad as yet. All you know is there is > an intermittent open between the point you are measuring along the path > to the battery through ground.
I think I know a little more than that, the starter is like a 0.05 ohm resistor, so if I had a bad connection chances are the voltage would drop a lot lower than 11.8V with the starter engaged. YMMV
> But given the known issue with the solenoid, I would suspect the contacts.
I think so, but I can add a wrinkle, I noted oil dripping from the starter/solenoid, so a new theory is the oil has contaminated the contacts in the solenoid causing intermittent operation. I'm going to hold off until the problem becomes more common or clears itself. I have tighten the very loose bolts holding the valve covers.
>How many miles since you replaced the contacts or the whole starter?
I don't know, but we don't put 5,000 a year on the truck, and the starter was replaced within two years. 91k miles now on a 17 year old vehicle, but the previous owner put on more than our 5K per year in 3 years, before we bought it. ( I thinking it had about 40k miles when we got it) Mikek
On 9/25/2014 1:23 PM, amdx wrote:
> On 9/25/2014 11:56 AM, rickman wrote: >> On 9/25/2014 11:56 AM, amdx wrote: >>> >>> > I'm having very intermittent lack of starter rotation on a Toyota >>> > T-100. Over the last 14 years I have replaced the contacts in the >>> > solenoid and more recently (1 to 2 years) replaced the starter. >>> > For trouble shooting I have a meter with one lead connected to the >>> > bolt on the solenoid and the other to the frame. (solenoid is built >>> into the starter) >>> >>> > The plan is; if I can get it to malfunction while trying to start it >>> > and the voltage on the solenoid is 12.7v vs 10.7 then I know the >>> > solenoid contacts didn't connect (if they clicked) or the starter is >>> > open (less likely). >>> > If the solenoid clicks and the voltage drops to a low value then I >>> > probably have a bad connection in the wiring. >>> > >>> > So far I have engaged the starter 25 times without malfunction. >>> > Letting things cool, then I'll try again, if I hit 100 my work is >>> >done for this go round! >>> >>> > Mikek >>> > >>> >>> >>> Ok, after about ten more times >>> switching the key to start, the starter did NOT engage. and the >>> voltage stayed at 11.9v VS 10.7 when the starter engaged. >>> >>> So by my logic I suspect the contacts in the solenoid. >>> >>> Anyone have other thoughts and a way to differentiate. >>> Oh, I like that going for a differential diagnoses! >>> >>> Mikek >>> >>> PS. I lament selling my Simpson 260, I had to grab a panel meter and >>> adjust it from a 75 volt meter to a 15 volt meter. Digital meters are >>> not real helpful for this type of testing. >> >> My Fluke meter has a bar graph at the bottom to give you some insight to >> what is going on when the digits aren't clear. >> >> I have a T100 and had the same solenoid contact problem which I >> repaired. Actually I should be due for them to go bad again, it's on >> 206 kmi now. >> >> I don't think you can say which is bad as yet. All you know is there is >> an intermittent open between the point you are measuring along the path >> to the battery through ground. > > I think I know a little more than that, the starter is like a 0.05 ohm > resistor, so if I had a bad connection chances are the voltage would > drop a lot lower than 11.8V with the starter engaged. YMMV
If the connection were intermittent it could be completely open and pass no current. That's what you think is happening in the solenoid, no? Starters have brushes... You would only notice a voltage change if the bad connection was between the meter and the battery. A bad ground connection would still read high on your meter.
>> But given the known issue with the solenoid, I would suspect the >> contacts. > > I think so, but I can add a wrinkle, I noted oil dripping from the > starter/solenoid, so a new theory is the oil has contaminated the > contacts in the solenoid causing intermittent operation. > I'm going to hold off until the problem becomes more common > or clears itself. I have tighten the very loose bolts holding the > valve covers.
Isn't the solenoid on top of the starter? Is the oil inside the solenoid?
>> How many miles since you replaced the contacts or the whole starter? > > I don't know, but we don't put 5,000 a year on the truck, and the > starter was replaced within two years. 91k miles now on a 17 year old > vehicle, but the previous owner put on more than our 5K per year in 3 > years, before we bought it. ( I thinking it had about 40k miles when we > got it)
That makes me think it is not the solenoid unless it really is your oil problem. Mine wore out around 100 kmiles and I recall that was typical. I got mine a year old with 11 kmiles on the odometer. The only complaint with the original owner is they smoked and I could smell it in the summer when I turned on the AC for maybe three years! It has held up well, but repairs are *expensive*. The AC seems to be a regular repair item. $1k every 5 or 6 years. Maybe I should get a Chevy unit? -- Rick
On Thu, 25 Sep 2014 09:56:44 -0700, rickman <gnuarm@gmail.com> wrote:

> ...snip TOO much!.... >
I had this exact, same symptom with my auto, 1972 classic. intermittent start, never got to measure but discovered that there was a build up of crud between the battery cable and the clamp to the battery cable that caused the whole problem. if not at battery, somewhere else along the path?
On 9/25/2014 5:02 PM, RobertMacy wrote:
> On Thu, 25 Sep 2014 09:56:44 -0700, rickman <gnuarm@gmail.com> wrote: > >> ...snip TOO much!.... >> > > I had this exact, same symptom with my auto, 1972 classic. intermittent > start, > > never got to measure but discovered that there was a build up of crud > between the battery cable and the clamp to the battery cable that caused > the whole problem. if not at battery, somewhere else along the path?
Uh, I think you snipped TOO much... I can't tell what you are replying to... lol Ah, you are replying to my post, but not really to me. -- Rick
On 9/25/2014 4:02 PM, RobertMacy wrote:
> On Thu, 25 Sep 2014 09:56:44 -0700, rickman <gnuarm@gmail.com> wrote: > >> ...snip TOO much!.... >> > > I had this exact, same symptom with my auto, 1972 classic. intermittent > start, > > never got to measure but discovered that there was a build up of crud > between the battery cable and the clamp to the battery cable that caused > the whole problem. if not at battery, somewhere else along the path?
Except that, when the starter fails to run I still have 11.9 volts on the input side of the solenoid, when the starter does run the voltage drops to 10.7 volts. Which I suggest is very close to battery voltage under starter load. I'm fairly confident the problem is the contacts in the solenoid. But as I've said I fixed the oil leak right above the starter/solenoid, and hope to burn off any oil by use. The last 100 starter attempts produce no failures. As I said very intermittent. (or cleared itself he wrote with fingers crossed) Mikek
amdx <nojunk@knology.net> wrote:
> On 9/25/2014 4:02 PM, RobertMacy wrote: >> On Thu, 25 Sep 2014 09:56:44 -0700, rickman <gnuarm@gmail.com> wrote: >> >>> ...snip TOO much!.... >>> >> >> I had this exact, same symptom with my auto, 1972 classic. intermittent >> start, >> >> never got to measure but discovered that there was a build up of crud >> between the battery cable and the clamp to the battery cable that caused >> the whole problem. if not at battery, somewhere else along the path? > > Except that, when the starter fails to run I still have 11.9 volts on > the input side of the solenoid, when the starter does run the voltage > drops to 10.7 volts. Which I suggest is very close to battery voltage under starter load. > I'm fairly confident the problem is the contacts in the solenoid. > But as I've said I fixed the oil leak right above the starter/solenoid, > and hope to burn off any oil by use. The last 100 starter attempts > produce no failures. As I said very intermittent. > (or cleared itself he wrote with fingers crossed) > > Mikek
I believe I've seen two problems on Toyotas. First was that the stationary contacts that the solenoid bridges got so worn that the solenoid would no longer reliably bridge them. Secondly, I believe I have also seen the brushes in the starter wear down to the point where they no longer made contact with the commutator and again, things stopped working (or maybe that was my compound mitre saw).
In article <832785067433387808.480825address_is-
invalid.invalid@shawnews>, address_is@invalid.invalid says...
> > amdx <nojunk@knology.net> wrote: > > On 9/25/2014 4:02 PM, RobertMacy wrote: > >> On Thu, 25 Sep 2014 09:56:44 -0700, rickman <gnuarm@gmail.com> wrote: > >> > >>> ...snip TOO much!.... > >>> > >> > >> I had this exact, same symptom with my auto, 1972 classic. intermittent > >> start, > >> > >> never got to measure but discovered that there was a build up of crud > >> between the battery cable and the clamp to the battery cable that caused > >> the whole problem. if not at battery, somewhere else along the path? > > > > Except that, when the starter fails to run I still have 11.9 volts on > > the input side of the solenoid, when the starter does run the voltage > > drops to 10.7 volts. Which I suggest is very close to battery voltage under starter load. > > I'm fairly confident the problem is the contacts in the solenoid. > > But as I've said I fixed the oil leak right above the starter/solenoid, > > and hope to burn off any oil by use. The last 100 starter attempts > > produce no failures. As I said very intermittent. > > (or cleared itself he wrote with fingers crossed) > > > > Mikek > > I believe I've seen two problems on Toyotas. First was that the stationary > contacts that the solenoid bridges got so worn that the solenoid would no > longer reliably bridge them. Secondly, I believe I have also seen the > brushes in the starter wear down to the point where they no longer made > contact with the commutator and again, things stopped working (or maybe > that was my compound mitre saw).
I'll put my 2 cents in.. Possible engine ground strap is loose and with all that oil running down the side, the attempts to start is heating up the bad joint and cooking the oil away, then has a semi connection to start, and it may start ok for some time after that. Taking a meter reading from the - side of the battery terminal over to the solenoid will show that you have 12 volts there. I had this problem years ago in an old ford straight 6 engine.. What flag me to the device giving me the problem was the fact that the alternator light would come on now and then and one day I noticed it would come on when I jumped into the engine, which made the engine move sideways a bit. The big issue is, if you don't get the oil problem corrected, it can cause an engine fire with all that oil, in the case of arcing. You could also have loose bolts on the starter! Jamie
On 9/25/2014 10:26 PM, Ralph Barone wrote:
> amdx <nojunk@knology.net> wrote: >> On 9/25/2014 4:02 PM, RobertMacy wrote: >>> On Thu, 25 Sep 2014 09:56:44 -0700, rickman <gnuarm@gmail.com> wrote: >>> >>>> ...snip TOO much!.... >>>> >>> >>> I had this exact, same symptom with my auto, 1972 classic. intermittent >>> start, >>> >>> never got to measure but discovered that there was a build up of crud >>> between the battery cable and the clamp to the battery cable that caused >>> the whole problem. if not at battery, somewhere else along the path? >> >> Except that, when the starter fails to run I still have 11.9 volts on >> the input side of the solenoid, when the starter does run the voltage >> drops to 10.7 volts. Which I suggest is very close to battery voltage under starter load. >> I'm fairly confident the problem is the contacts in the solenoid. >> But as I've said I fixed the oil leak right above the starter/solenoid, >> and hope to burn off any oil by use. The last 100 starter attempts >> produce no failures. As I said very intermittent. >> (or cleared itself he wrote with fingers crossed) >> >> Mikek > > I believe I've seen two problems on Toyotas. First was that the stationary > contacts that the solenoid bridges got so worn that the solenoid would no > longer reliably bridge them. Secondly, I believe I have also seen the > brushes in the starter wear down to the point where they no longer made > contact with the commutator and again, things stopped working (or maybe > that was my compound mitre saw).
The starter brushes will wear in any vehicle although they usually don't stop making contact, instead the carbon wears away until the metal backing wears down the contacts on the rotor destroying it (much like your brake pads do). But maybe they put in a stop to prevent that. The solenoid in this model Toyota starter has an issue where the plunger bridges the two contacts, but doesn't balance the pressure. So once one starts to wear more than the other it has less pressure and becomes the point of make/break taking all the wear. At some point the one contact wears away to the point of not working... much sooner than if the bridge across the two contacts was able to float and provide equal pressure at all times. At least that is how I remember it. -- Rick