Replacing DD8v71 starter with 39MT - confirming wiring

[windtrader]

Wiring looks a bit different, just want confirm where wires go on new starter. Also, is that bolt head a standard 12pt or a special socket?

[chessie4905]

12 point socket will work.They use that design due to insufficient clearance for a 6 point capscrew. I would recommend a 12 point impact socket for this use, as they are more robust, although a standard 12 point will work if it doesn't take 500 lb ft to break it loose. Don't allow socket to get side cocked when loosening which could result in slippage and rounding of head.

[luvrbus]

You have a long womble extension it is easier to use, 2 bolts come out easy the one on the outside takes a shallow socket with a long extension,or box end wrench remove it first !!!! .The wiring is same ground,start wire and battery cable.Is that a Delco ?   

[bobofthenorth]

For whatever its worth the instructions that came my Delco were very specific about having a second start relay in the circuit. Power from the key energized that start relay and it energized the start relay on the starter which in turn energized the solenoid on the Delco.  It seemed like overkill to me but that's what the instructions said.

[chessie4905]

The start relay in the 4104 has a history of sticking from long term point degradation. It causes the starter to keep cranking after releasing start button. Will burn up starter if you can't disconnect batteries quick enough. I believe the culprit relay is in the voltage regulator box. Common Little relay. Should be replaced if owner hasn't already done so.

[eagle19952]

The start relay in the 4104 has a history of sticking from long term point degradation. It causes the starter to keep cranking after releasing start button. Will burn up starter if you can't disconnect batteries quick enough. I believe the culprit relay is in the voltage regulator box. Common Little relay. Should be replaced if owner hasn't already done so.

we always replaced all of the 15/16 headed bolts with 12 point.
at 40 below...you appreciate the little things.
at 98 above or
born before 1950...you will too.

[luvrbus]

For whatever its worth the instructions that came my Delco were very specific about having a second start relay in the circuit. Power from the key energized that start relay and it energized the start relay on the starter which in turn energized the solenoid on the Delco.  It seemed like overkill to me but that's what the instructions said.

That why I was asking if was a Delco Bob the second relay is for the soft start feature

[windtrader]

Clifford,
Yes, it is the real deal. You advised me about the cheap fakes. Stickers and box have Delco-Remy labels. Like a kid with a birthday present, just grabbed the starter from the box; upon actually looking inside the box just now there is an instruction sheet. Thanks for the tip! lol

[bobofthenorth]

That's the real deal.  Take your time and savour the installation experience.  I'm willing to bet that's the last time you'll ever touch that starter.

[windtrader]

Update.

New starter swap was simple and quick. Thanks Clifford about the short socket on the back bolt and the wobble extension. As forewarned, the old one is a lot heavier as it went thud onto the ground. lol

Most time was spent studying the instructions and making sure removing the relay on the new unit was necessary and then getting the wires connected correctly to the new starter as there is a slight difference.

It's really amazing how well it works. The bus started so fast I didn't even hear it engage; just an instant VROOM!

Couple things. The new starter touches on a valve on the block. Initially, I thought, Shiite, it needs to come all the way off. After studying the touching terminal it was a relief that it's ground so decided to leave it as is. Other was bonehead, dropping the terminal nut into the gravel. Did not have any extra hardware on hand so just placed the wires on the terminal post in a way to keep pressure on temporarily.

[eagle19952]

Update.

needs clocked.
that fitting can be moved...
that's an incident waiting to happen.
or don't.

[luvrbus]

That is your air box drain I don't know if you can clock that MT39 or not some you can some you cannot but you can always change the air box fitting

[windtrader]

ok, i'll check clocking first, the starter can do it easily; hope there is enough slack in the wires. Thanks!

[luvrbus]

It will tell you on the box or instructions if the head is rotatable or not,it is a option on the 39MT 

[Iceni John]

Or rotate the airbox drain valve so it's not pointing straight down.   As long as it's pointing slightly downhill it will work OK.   I did that to both of mine, then ran some tubes from them to a catch can tucked inside the rear bumper  -  I can now see exactly how much is slobbering out, and it doesn't leave black spots on the ground.   Well worth it.

John