Accessory Drive Overhaul

Getting rid of everything but the alternator

Posted on November 10th at 4:02pm

Preface

The accessory drive on the 07k is quite elaborate. For this 2005 motor the crankshaft pulley drives the alternator, water pump and A/C compressor. Therare two tracks (two belts) that drive this whole assembly. The pulley that connects these two track together is attached to the A/C compressor. I will not be running A/C in this build so there is a problem of how to delete the A/C but keep the water pump and alternator turning. See pic below for visual representation.

Solution

After some brainstorming I decided to keep only the alternator turning via the crankshaft pulley. The water pump will be blocked off and use an electric pump instead to keep coolant flowing. The A/C compressor will be simply removed. There are a couple reasons I went this route:

The alternator is easily moved

The alternator is a whole unit that can be completely removed from the engine and relocated in any place. This includes shifting it over to track 1 that the crank pulley can turn on its own without needing a second track and common pulley. The plan is to fabricate a custom bracket and use an off the shelf shorter belt to get things connected and keep the battery charged.

The water pump cannot be easily moved

Contrary to the above point the water pump cannot be moved because it bolts straight to the block. This creates a permanent location to track 2 which we will be removing. In order to easily move the alternator I decided to do a remote electric water pump. Not only does this solve the water pump drive issue but an electric water pump has better output when engine RPM's are low. This equates to better cooling at low speeds which being in the city I see as an added benefit.

Process

Removing items

We have to remove the accessory braket and the water pump. There is one bolt that cant be removed unless the belt tensioner is removed first.

In the previous pics the water pump was shown already removed but here is a before and after. By turning the pulley you can see three bolts behind it that need to be removed. With a good pull the pump will pop right out.

Mocking up new alternator location and belt size

I want the alternator to sit pretty low so it is out of the way of the intake and any intercooler or coolant piping that could utilize the space. I held up the alternator about where i wanted it to sit. I then took a peice of string and wrapped it around both pulleys to act like a makeshift belt. I then cut the string and measured end to end. I found an off the shelf belt that is the correct size.

Threaded holes in the block that the new alternator mount will bolt to.

Sizing up some scrap to start fabricating.

Drilled a couple holes for the lower mount rail.

Welded up the flanges and middle support tube for the lower alternamotor mount holes.

Test fitting on alternator and block.

Orderd some new Grade 12 hardware that's a touch shorter for less excess on the end.

Bottom mount all bolted up and fitting great.

Squaring up the top rail flange

All finished sans new hardware

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