6.2 cooling system/serpentine upgrade

[Milblazer]

Seeing how my truck is having issues staying cool lately I have decided to perform a bit of an overhaul of the cooling system and convert it to a serpentine belt system. I believe either the radiator is blocked in areas or the water pump is on it's last legs. If I'm going to be removing the water pump I might as well put in the upgraded water pump off of a 6.5. Converting to a serpentine set up has been the plan for a while and I have been collecting parts for over a year, watching on fleabay and keeping an eye on specials so I can buy them for a good price.

Here is what I plan on doing:

-"New" radiator
-New* water pump (AC Delco 251-590) with "6.5 backing plate" (GM 12562659)
-New vacuum pump (AC Delco 215-479)
-"New" alternator (140 amp)
-A/C bypass bracket/pulley (GM 12555023/14102597)
-New* power steering pump (current one started making squealing sounds) (AC Delco 36-517137)
-New fan and fan clutch (AC Delco 15010202/Hayden 2839)
-New belt tensioner (AC Delco 38118)
-Add "serpentine brackets" with new GM bolts
-New radiator mounts. (P/N 6264100 from summit)

" '' = part from a pull and pay or a used part
* = a remanufactured part


First step for me was to drain the oil and trans fluid as the 6.2 radiator has a built in cooler for those and I didnt want that stuff all over my engine bay. While preparing for the swap I had a spare radiator I got from a pull and pay sent to a local radiator shop to be rodded and cleaned so no more problems would appear. I also ordered some new radiator mounts because if its out I might as well replace those. So far I have drained and pulled the old radiator. I'm waiting for the weather to warm up a bit so I can get back at it. Also I'm waiting on some partsl not that I'm complaining when tomorrows high is supposed to be around 7.

 

[Milblazer]

Got a bit antsy and put my new fan and clutch together

 

[Milblazer]

Power steering pump came today so I got that mounted up and the pulley put on. I need to figure out how to get the bolts off the back of the other pump I have as they seem to be a pain in the ass to get out.

 

[Stroked]

Nice! The serpentine setup is a huge upgrade for the 6.2 in my opinion.

Sent from my Kindle Fire HDX using Tapatalk

 

[Milblazer]

It will be nice to not have to adjust the v-belts every couple of months and have to re-tighten everything with a big ol piece of wood. Plus I get to add a higher capacity water pump, a fan that pulls more air over the engine, and a larger amperage alternator.

 

[Milblazer]

Slowly getting there. Still waiting for the backing plate so I can mount everything.

 

[Milblazer]

Well I got the new backing plate yesterday. Used RTV and a gasket to seal the water pump up to it, hopefully there won't be any leaks. Learned a few things while doing this swap. You want to wait until AFTER the driver's side bracket is bolted to the engine to bolt on the power steering pump and add the pulley for it. There is bolt that needs to go in and with the steering pump mounted it is in the way. I had to slightly bend on of the power steering return lines up so it would not be resting on the frame.

I've also had to carefully bend some of the fuel lines as well as they would have sat right up against the bracket and I didnt want any pinhole leaks in the future. I used some rubber fuel line to protect the metal fuel lines where they might rub up.

On the passenger bracket I did run into a problem. On the 6.5 diesel heads there are three mounting holes in the sides of the head. On the 6.2 heads there are only two so I only have one bolt in the head and two nuts attached to the water pump holding that bracket on. Might have to add some loctite on there so nothing comes undone.

When I mounted the vacuum pump it ended up hitting one of the metal fuel lines from the fuel pump so I had to bend that a bit so everything fits just fine without rubbing.

A big problem I am running into is finding a coolant crossover that will fit. I have one from a 6.5 but it was hitting the fuel line that had to bent to fit. I'm going to see how the 6.5 was set up and see where that will get me. I'm still waiting on the dummy pulley for the AC mount and I need to get some bolts for the crankshaft pulley, also hook up the vacuum lines and do a few odds and ends and i'll be good to go.

 

[Milblazer]

Well I got lucky and found a diesel van at the pull and pay. Grabbed the coolant crossover and tested it and the main issue was that it hit the drivers side bracket on one of the compressor bolt mounts. Little time with the angle grinder and it fits, although pretty tightly.

 

[Milblazer]

This is the thermostat housing I need. No Idea what year it is off of. This article says its from an early 6.2.

http://www.dieselpowermag.com/tech/general/0703dp_gm_diesel_engine_swap/photo_03.html

 

[Milblazer]

The bolts for my crankshaft pulley came today. Decided to test fit the serpentine belt by putting on the dummy AC bracket I have. I took a risk and went with a doorman part and it arrived with a chip out of the pulley. The pulley is a real light flimsy plastic. Not surprised it broke but I did re-learn a lesson, follow the damn plan and stick with GM or AC Delco. Still have some things to do but I am getting closer to firing her back up.

 

[Milblazer]

I tracked down a thermostat housing that would work for my truck. GM part 12551519. It is the first design of the 1996 model year and is available for only that year. I got it and it fits perfectly but it would hit the throttle cable bracket so I had to do a bit of custom fabricating. The first bracket I got off of a gm car that I believe was front wheel drive. When I go back to the pull and pay I'll look and find the make and model. The other half was the 6.2 bracket and I did a test fit and it looked like it will work. I did a test fit and it looked tight but should work. Don't quote me on that as it's dark out and I couldn't see very well. One step closer to having my truck back.

 

[Milblazer]

Got a few issues I had with some fusible link resolved today, added an 8 gauge wire to the passenger battery from the back of the alternator, bled the fuel system, cursed a lot and got it started, finally! I'll have to say this is the smoothest this truck has ever ran and i'm thinking the fluidampr harmonic balancer has a lot to do with that. When I pulled the old one the rubber on the front looked alright but the rubber on the back was cracked and deteriorating. The new fan is really loud too lol. Also if you forget to put something on the old vacuum pump's rubber hose you might wonder why your truck sounds like a steam train.

 

[Stroked]

Looks good! I considered getting a Fluidampr for mine, but I didn't have the cash for it at the time.

 

[Milblazer]

Looks good! I considered getting a Fluidampr for mine, but I didn't have the cash for it at the time.

I didn't either. I got it a couple years ago off a used truck with 5000 miles on it and it has been sitting ever since. It was a damn good deal that I couldnt pass up.

 

[Joseph]

What are the benefits in upgrading/converting a 6.2L engine with a serpentine system?

Thank You

Joseph