Very slow to crank when cold...Problem?

[nelsonj]

Hello all,
I tend to only drive my spider on nice weekends (relatively stock 78 drive train, stock starter). If I haven't started the car for a while (even a few days), when I turn the key, the car turns over very, very slowly at first (like one turn every 2 seconds). As it cranks, it starts to slowly build up speed, and eventually gets going fast enough to start the engine. If I drive the car for awhile (say 25-40 miles), the next "hot" or "warm" start the engine cranks over at a reasonable speed from the initial get go. But if the car sits for a few days, I now expect a very slow crank to get the car started.

As first I thought my battery was going dead, but it always has enough power to crank the car over, and over again, and the car always starts. However, something is not right and I am getting a bit nervous that the day will come where I won't be able to get it started.

Questions:
1) Anyone else have this problem? What did they do do solve it?
2) I am thinking about just cleaning up the battery cables, adding diaelectric and tightening them up real good. Just seems like there is not enough current getting to the starter...
3) Since my starter cranks, is it still good? or is this a typcial "starter motor failure" problem?

Thanks in advance for sharing any wisdom on this issue.

[So Cal Mark]

you really need to do some testing with a voltmeter to determine anything

[seabeelt]

I would start with the connections and go from there to the testing. Ususlly if the starter motor is going bad its the ohter way around. Starts fine cold and then bogs down when hot

[Kev659]

I had a similar problem with my 79. I cleaned every ground I could find then went through the wire diagram from battery to plugs and found an aftermarket box connected to the coil. Not sure what it was for but it was not part of the original electrical system. I disconnected it and now it starts fine every time in fact it run even better. Your problems do sound electrical in nature.

[nelsonj]

Turns out my 100 month battery was going bad a 27 months. New battery installed, probelm now solved.
I note that I got it at Costco, and since it was less than three years old, they gave me a brand new battery, at no cost (no pro-ration at all). They didn't even test it. I think all my future battery purchases will be from Costco.

Thanks for the feedback.