Starter is slow, then fast???

[DennisG01]

For the past month or so, the first 1/2 to 1 second of cranking results in very slow "turning over". After that initial second, the engine turns over normally (fast) and starts. The only way I can think to describe it, is as if something is physically holding the engine from turning (or just letting it turn very slowly) for second, and then that thing "lets go" and allows the engine to turn over normally.

Another way to maybe explain it... I get about 2 "turning over" revolutions (crank/puff sounds) where it is noticeably slow. After that, tit's normal.

Did I just make my explanation even more confusing? :):rolleyes:

Cables/connections are clean and tight (relatively new, as well). The starter cable (at the starter) is tight, but I wasn't able to verify if it was clean. I have not load tested the batteries, but after a night of sitting, they're still at about 12-1/2 volts (using a DVM).

If it was bad cables/connections/batteries, I would expect that the slow cranking wouldn't "fix itself"???

I use Rotella T6 synthetic (5W-40).

[DmaxMaverick]

It could be any number of electrical problems, but it's probably just the glow plug cycle ending, allowing more juice for the starter. At your next cold start, when you'd expect this to happen, disconnect the GP relay before cranking. It won't (shouldn't) start, but it should crank normally if it was the GP cycle causing the slow cranking.

[rapidoxidationman]

My '05 was doing exactly this on the first start of the (cold) morning. Subsequent starts through the day were OK, but not awe inspiring. I was bummed at the prospect of dropping $250 on a new pair of batteries, so I checked the battery terminals - they each had a minute amount of play in them. Cleaned, shot with silicone spray, tightened up, and starting like crazy now.

Double check your battery terminals? The voltage drop at a loose connection, even if it is just a tiny bit loose, can be significant.

[jhornsby3]

Try swapping your batts around. I found that the pass side batt won't get the same charging at the drivers side. And with the power to the starter coming off the pass batt it might be lower crank power until the alt is cranking. It's a guess but stranger things have happened.

When I had batt, alt issues I found that the pass side gets a lower voltage due to the restance from the cables than the drivers side.I found that by switching them around about four times a year has helped with the charging and they both charge up equally now.

[DennisG01]

So, I went out to start messing around and I figured that before I unhooked the GP controller (I rechecked the connections, first), I would simply try to start it right away - like you would a gasser. Except this time, I get dim dash lights, funny sounding bells/whistles and a starter that is just clicking. So I think to myself: "Well, what the heck could be the.... DING, DING, DING (that was the lightbulb turning on in my head, albeit a little time-delyaed). When I volt-tested the batteries (post #1) I never disconnected the positive cable that ties the two batteries together! Duh! Of course they'll read the same!

So, I quickly tested the batteries again (still connected) and noted that they were now down to about 11.8v, sitting for a solid 24 hours. I disconnected them and one started to immediately climb back up over 12v and the other was diving down towards the 10v range. A quick look at the date stamp on the battery cases and turns out that these batteries are 6 years old. For the life of me, I thought I had replaced them 3 years ago! They are pro-rated for 84 months from a parts store, though. So, I load 'em both into the other car (a closer look at them reveals the cases starting to swell) and about 45 minutes later the engine starts up like it's on steroids!

What a bonehead I am!

[DmaxMaverick]

It happens to all of us, from time to time. Unfortunately, it doesn't get less frequent as we get older. It's always a good feeling when your truck acts right again.

[Robyn]

Haaaaaaaaaaaaaa, yup meee tooooooooo.
Back in Sept after I sold the big rig, the new owners called and asked about the batteries as the thing would not start.

Ahhhhhhhhhh, geeeeeeeez they are only a couple years old I said, so I went to see him and we removed the batteries.

OOOOOOOOPS UMMMMMM. 8 years old. Time flies when yur havin fun eh ??:o:o

[DennisG01]

Well, at least I can take solace in knowing that I'm in good company!:)