My D2 is slow to crank over, it's consitant in how slow it is and can sit for a couple days and still cranks over the same. Just not how it used to.
Seem's to have started after my head gasket job but not 100% sure on that. The whole engine transmission was cleaned and de-greased before I started the HG job.

The alternator tests good and it has a new battery installed a few days ago. Group34 800CCA.
All other electronics work as normal, no dim headlights or anything and she runs perfectly.

I've cleaned ground connections to engine and hot battery connection at starter as well as the small connection for solenoid.

Any ideas? Something needs cleaning that I've missed?

Autozone has a their brand starter with solenoid for right at $100 and with a coupon code I have it'll be just over $75 after core charge refund.

Thanks all.

 

To double confirm, check the cables at the battery. Maybe even get a piece of thick gauge wire and strip it back and wedge between post and cable clamp.

Then try adding a jumper box of other cars battery. If still the same, you can rule out battery and connection at battery.

 

Clamp and post are clean and very tight and I got the new battery thinking the 3 year old one was the issue. Same symptoms with new battery, so I think I can rule out the battery and connection at the post.

I do have a long winch cable I might try running separate to the starter positive post to the battery, might rule out a crappy cable as it runs under the engine and could be corroded. I'll post back.

 

I can think of possibly two issues, first is the contacts in the starter motor solenoid are coated after arcing, either dirty or pitted, or secondly the starter motor brushes are toast. It does sound like your starter motor needs a rebuild.

 

I wanted to follow up on this and thanks to those who replied.
It was definately the starter. Popped a new in in and it cranks like new.

Also wanted to note a couple things, I went for the Autozone "Carquest" remanufactured starter that was under $100. To my surprise when I got it home and it's quite clear it's a genuine LR branded Bosch rebuilt unit.
Even the new solenoid is Bosch branded. Now I'm not sure about the quality of the rebuild parts inside but it was reman'd in Mexico where they are made anyway as far as I know.
Some pictures attached for posterity.

 

Great to hear you're sorted successfully