whateg01
Well-known member
Never trust the voltmeter in the dash except as a rough guess. You need a new battery.
Starter Motors
- Thread starter Wamsutta
- Start date
Old Man Roger
Well-known member
Old Man Roger
Well-known member
Low
seber
Well-known member
Since this is GJ the correct answer is buy a digital batter tester. They are pretty cheap. I never thought I needed one until I got it. Now I find uses for it at least once a week.
How old is the battery? Easy enough to go to Advance/Autozone/whatever and get it (and the alternator) checked.
Trouble on a warm start would have me looking at the battery and/or the alternator . 14.6v is on the high end of normal charging voltage. Probably fine, but it takes a few seconds for them to test, and it's free.
richfinn
Well-known member
Test don't Guess!!
You can use the min/max function on a multimeter to record cranking voltage/voltage drop on both positive/negative sides of the circuit.
A DC amp clamp will tell you if the starter motor is drawing excessive current/not enough current/if the battery is accepting a good charge.
You can use the min/max function on a multimeter to record cranking voltage/voltage drop on both positive/negative sides of the circuit.
A DC amp clamp will tell you if the starter motor is drawing excessive current/not enough current/if the battery is accepting a good charge.
joel63
Well-known member
^^^^^^ This is right. ^^^^
ToolsRCool
Well-known member
Which vehicle? The semi in your profile pic?
The starter you are describing is most likely worn out. The clicking you hear is the solenoid engaging, but then that is all you are hearing because no power is being sent to the motor armature to rotate it. This is either because the brushes in the motor end have worn beyond their useful life (no brush spring pressure remaining), or the contact bus bar in the end of the solenoid cap is worn. Under the non-removable solenoid cap, there is a copper bar that connects the two large studs together only when engaged, and this sends high current power to the motor below it, once the pinion is engaged.
On batteries, 12.8v is a fully charged like new battery at rest. 12.0v is about 80% discharged. As a battery ages, it will have a hard time ever recharging to 12.8v as its internal resistance increases. Typical battery life is about 5 years. They can last longer, and a lot of people will judge that by if it still starts the engine, but it will likely not be able to supply its CCA label rating anymore.
Every engine can act as a battery load tester. Digital voltmeter on the battery terminals while cranking, you really don't want to see it dip below 10.0v. The higher it can hold the voltage while cranking, the healthier it is. A lower CCA rated battery of a same case size as a high CCA battery can typically last longer, but aftermarket replacement batteries are often judged by max CCA instead. Typical KW semi truck will use 4x650cca group 31 sized batteries, but most group 31 replacements are rated at 1000cca.
Modern gear reduction automotive starters (since early 90's) have done away with the hot soak issue that cursed big engines in history. They use permanent magnet fields instead of coil wound, which those increase in resistance with heat.
A "Bendix" is the older type of helical engagement used on direct drive starters. These used fender mounted relays to switch high current on and off to the starter. The modern solenoid shift starter has integrated both of those features into itself, pinion engagement and high current switching.
Just 30 seconds of stuff if anybody wanted.
I went and got a new battery from Costco last night. It's an Interstate battery. Eric on South Main Auto says the new generation of Interstate batteries are junk. I went ahead and took a chance so I could use my Costco credit card. Bank account is kinda low after paying a round of bills. I wanted to get another NAPA because they're a much better looking battery and has a built-in carry strap, but it's a $100 more than the Interstate from Costco. The new battery measured 12.53V standing by itself and 12.61V hooked up to the battery cables. I don't understand why the voltage would be higher with the battery connected to the battery cables when I haven't even started the car up yet. With the engine running, battery voltage is 14.79V. Battery lives in a battery compartment under the back seat.
The new starter motor showed up yesterday. I haven't installed it yet. It's a brand new Bosch. The original starter is still doing fine except for the occasional dead spot while cranking sometimes. I haven't found out how the original starter motor will act with the new battery yet. I'll find out later on today.
The new starter motor showed up yesterday. I haven't installed it yet. It's a brand new Bosch. The original starter is still doing fine except for the occasional dead spot while cranking sometimes. I haven't found out how the original starter motor will act with the new battery yet. I'll find out later on today.
whateg01
Well-known member
That's what I always look for when buying stuff I depend on. Prettier.
Old Man Roger
Well-known member
So with the new battery the starter still failed?
richfinn
Well-known member
Awesome, what a waste of a thread 
There was a dead spot while cranking today, but I held the key in start position until the starter was able to crank the engine. It's like the engine is locked up momentarily until the key is turned again. At other times the starter turns the engine just fine. Can't figure it out.
nadogail
Well-known member
Solenoids act that way when failing.
Your injector is leaking down on one cylinder when when engine is off and hydrolocking the cylinder with fuel on compression stroke.as I posted earlier in post #25. The reason it doesnt do it all the time is when you shut the car off the engine may stop on a different cylinder than the one with the leaking injector. If it stops on the leking injector cylinder on compression stroke valves closed and you turn it over with fuel in cylinder it is pretty hard to compress without harming things. Keep buying batteries and starters though it helps the economy. 3.8 intakesgaskets are known to go out and leak dexcool antifreeze into engine but that most likely isn't this case. You could try a strong dose of techron injector cleaner run through your gas tank and use top tier fuel on the next fuel ups it may clean the carbon out of the injector and fix it otherwise you'll have to replace the injector thats the problem.Also might pull the platic hose off the fuel pressure regulatot and see if the diaphram is bad ,if so it will be wet with fuel.
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rust in the eye
Well-known member
An inlector leaking down this much would also manifest with severe misfiring once the engine starts as that cylinder would be profoundly flooded. It would also emit black smoke and the oil would be very diluted. Neither symptom has been mentioned. Likewise for coolant in the cylinder. Consuming enough coolant to hydro lock repeatedly wouldn't likely go un-noticed either.
NONE of this is going to get diagnosed remotely with a keyboard. OP needs to perform some tests or hire the job out.
I don't know about that. If I were diaging it, in the absence of codes, after a visual inspection, the starter and the electrical connections is where i'd start. If it were mine, I probably would do that, but I wouldn't fault the diy guy who doesn't have good test equipment who cannoned a starter at it. especially if they can at least do a voltage drop to the starter and its ground. And a good phsycial inspection, bad cables can cause lots of problems.
whateg01
Well-known member
Pretty strange that without doing anything to address the hydrolocked condition, just simply turning the key again causes the car to start, don't you think?
No ,pressure bleeds off and rolls over tdc. Could also mention I own 1999 Buick regal ls 3.8 1 2003 and 1 2004 lesabres customs with 3.8 all 3 had the intake gaskets replaced along with elbows. 2 of these had injectors leaking bleeding down while sitting causing a symptom like over advanced timing but was actually trying to compress fuel, and all 3 had the fuel pressure regulators go out and spurt fuel into the vacuum line.
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whateg01
Well-known member
Oh, I heard HF has a new set of pliers that would be perfect for that!
You know I was fired from that job over two years ago. 11/12/2022 to be exact. If you remember, I took it upon myself to dispose of those two 4ft long fluorescent light bulbs that were laying in the parking lot by throwing them up in the air. A customer turned me in for being extremely reckless and an imminent danger to society. Home Depot fired me for improper disposal of hazardous waste.