Canadian Hummer Club Forums

I thought i would write up a info and install tutorial on the upgraded fluidampr harmonic balancer for our 6.5L TD. Not many know of the failures regarding harmonic balancer failure on the 6.5 but it is often a widely overlooked item on our engines. Having been rummaging around the net, reading tidbits of info and such from the gm truck guys; on keeping the 6.5 running for a long time. one of the most common catastrophic failures on the 6.5 was the harmonic balancer failure which in turned caused the crank to break. Now i can get into all the info and tidbits about crankshaft torsional shocks and first order & second order harmonics, but in short, a harmonic balancer keeps a engine (especially a diesel) from violently exploding <img src='http://www.canadianhummerclub.com/forum ... #>/huh.gif' class='bbc_emoticon' alt=':huh:' /> and is a very crucial part of having a happy and smooth running engine. The original harmonic balancer on the 6.5 had a rubber pressed ring that would absorb the vibration, the problem was that, over time the rubber would loose it elasticity and begin to fail (most commonly seen by swelling of the rubber, cracks, and bits of rubber missing). Mine however looked good, but not knowing if it had been replaced at, it was definitely on my to-do list. After looking around at replacement ones, i wanted something better then stock, you know, if your going to spend the time to replace something, midas well replace it with something better if you got everything apart already. Personally in my opinion the way the stock one was made was not very well engineered (for a gas engine a rubber damper is ok, but with the higher shocks a diesel sees, there’s room for improvement). On the gm forums, many suggest to replace it every 100,000miles or 6-8 years. Even if you don’t have a lot of mileage, rubber does deteriorate from the ozone in the air. Having a upgraded absorbing damper will also help save ware and tare on your lower bearings and such.



Soo.. i remember talking to my neighbor about the harmonic balancer (he builds race cars) and he showed me one of his Fluidamprs for one of his race cars. After a quick search on the net, I see that they now have one for our diesel. Awesome I thought. After doing a bit more research, and then talking to one of the guys at Fluidampr, I had one on the way, and couldn’t wait to see what it was all about. <img src='http://www.canadianhummerclub.com/forum ... iggrin.gif' class='bbc_emoticon' alt=':D' /> P/N 800141 is for the newer style 6.5's 2000+ I believe. Verify which one you have, they have a different style for the older 6.5's that have/don’t have a crank sensor on the front.



In the meantime, i hunted around for a crank gasket. From the looks of it underneath, it looked to be leaking oil from the crank gasket (the only front crank gasket on this engine is located on the chain case, and seals around the damper shaft). I was able to find a complete front gasket kit, the kit included the crank seal that i needed. Look for FEL-PRO # TCS-45554 this kit will have more then what you need (front pan gasket, chain cover gasket, water pump gaskets...) it was like 29$.



Once it came in, it was pure engineering bliss. The machining quality was top notch, i love looking at the tooling swirls, and trying to figure out the depth passes and tooling paths as it was being made. I’m sick in the head for that kind of stuff. <img src='http://www.canadianhummerclub.com/forum ... rgreen.gif' class='bbc_emoticon' alt=':mrgreen:' /> sometimes i chuck a piece of steel in the lathe just to see some chips fly for my amusement. lol

Other then that, anodizing finish was excellent, and so was all the engraving.




Install was pretty straight forward, but there is no cheating steps, the H1 engine bay is pretty snug, and there’s only 1 way to take things apart. Plus your gonna need some certain tools. This install is for the 6.5 with new style water pump and single large fan bolt. I don’t know what different tools you will need for the older style 6.5. Anyways, you will need a 36" pipe wrench (or similar with at least a 4" jaw opening, but width is important because if its too wide you wont be able to fit all tools in), i picked up a princess auto 2921922 36" pipe wrench. and I believe a 1-7/8" wrench to put on the fan nut. AMG has a special spanner nut to fit onto the water pump pulley, but if you don’t have that, the pipe wrench works good. The pulley is pretty heavy duty, so there should be no fear in bending it. Last you will need a universal impact joint adaptor. This is needed for when you want to take the lower pulley bolts off, and the balancer bolt off with a impact. The fan should prevents you getting any large tools in there. PA# 8036287. A large torque wrench 200ft/lbs+, and Some blue locktie is good to have on hand as well. Don’t use the red permanent strength stuff.



Ok your ready to go. I wish i had more pics, but once i got going, things were just flying off and on.

First, take off the serpentine belt. 5 seconds with a 3/8 ratchet, there’s a notch in the tensioner pulley housing to put the ratchet in..





Next is a 2 person job. Put the pipe wrench on the 2nd ridge of the water pump pulley (not on the surface that the belt rides on), and the 1-7/8" wrench on the fan nut. And give it a good tug. Once loose, you will soon realize that the fan will not come out, no matter what amount of wiggling or trying to pull the fan from out of the shroud housing. Don’t force it, if it wont come out, good luck trying to get it back in if it magically did come out. <img src='http://www.canadianhummerclub.com/forum ... tongue.gif' class='bbc_emoticon' alt=':P' /> On the back of the fan you will see 4 bolts, this attaches the clutch to the blades. Remove them, and the clutch feely comes off, you can then pull the fan out. <img src='http://www.canadianhummerclub.com/forum ... iggrin.gif' class='bbc_emoticon' alt=':D' />

Ok now on the lower crank pulley. Using the universal impact joint, and a powerful impact gun, but not large in physical size (too big and it wont fit into the rad shroud area. Take the 4 pulley bolts off. you might need to use a wrench from down below to turn the engine so you can reach the last 2 bolts. Off it comes, and now you can see the harmonic balancer.




Impact the middle bolt off, and your good to go. Now this is where you might hit a snag in the road. My balancer pulled right off without the use of a balancer puller. You might actually need to use one. Good luck. <img src='http://www.canadianhummerclub.com/forum ... iggrin.gif' class='bbc_emoticon' alt='' /> there isn’t much room to fit one.



With that off, now you can see the crank, and the "probably" leaky shaft seal. Taking the seal off is kind of a pain. I had a special seal puller, and i couldn’t get it in there to work. A good ol hefty set of cutters to get a good grip, and a firm tug got it off. Just be careful not to scratch the outer case seal surface.



Now a new challenge, getting the new seal on. This could be a 1 min - 1 hour task. Because the crank is in the way, you cant really use a standard seal inserting tool, and using a small hammer is tedious. You gotta have the seal seated straight on or you will bend it if it doesn’t go in straight. AMG has a special tool that’s hollow to go around the crank, but its not too easy to get a hold of. I myself had a thick aluminum plate laying around that i drilled a hole into and worked great for tapping the seal in. Others recommend using a large ABS pipe end cap, and drilling a hole in the end to slide past the crank to seat the seal.

Once its flush , your good to go!.

Squirt some engine oil on the seal surface of the balancer, as well as the seal .



Place the new fluidampr on the edge of the crank, and slowly turn it on the crank until you feel it catch the key, then proceed to put it on the crank. Fluidampr recommends making a pulley inserting tool. They say "A damper installer makes installation a snap. It's easy to

strip the threads in the end of the crank if you attempt to run

the damper onto the crank using the damper bolt. You can

make a damper installer by buying a metric bolt that fits the

crankshaft (M16 x 1.5), weld a piece of all-thread onto that

new bolt you bought, then use a nut on the all-thread to get

the damper fully seated onto the crank"





Next, if you prefer, put some blue loctite on the balancer bolt, and torque the crank bolt to 200 ft-lbs. The motor will probably try to turn at around 120ft-lbs. thread 2 short bolts into the balancer (not the original pulley bolts incase you bend them), and place the closed end of the large 1-7/8" on one bolt, and the rest of the wrench across the 2nd. Have a helper hold, or you can fandangle it through the undercarriage protection to hold it in place as you torque to 200 ft-lbs. If this makes you squirm. You can get the flywheel lock pawl that goes where the starter bolts in i believe. <img src='http://www.canadianhummerclub.com/forum ... /wacko.gif' class='bbc_emoticon' alt=':wacko:' />




Ok, after that, your in the home stretch, a bit of blue loctite on the pulley bolts if you prefer, and put them on. Torque to 48 ft-lbs.



Reinstall fan, put on belt <img src='http://www.canadianhummerclub.com/forum ... SMILEY.gif' class='bbc_emoticon' alt=':woot:' />



Start it up, if it doesn’t fall apart, your good to go! <img src='http://www.canadianhummerclub.com/forum ... cheers.gif' class='bbc_emoticon' alt=':cheers:' />


First time i started it up, instantly i noticed the reduced idling vibration. And as she warmed up, and quieted down, inside it was like it was barely running (vibration wize). After putting on about 300km since install 2 weeks ago. Its not only a bit smoother, but i now have some piece of mind that i have nothing to worry about when driving around, especially on the hwy at higher rpms. and having the balancer let go. Plus the new balancer looks cooler!



If any of you guys are interested in upgrading your balancer, give Fluidampr a call 716-592-1000. You can order them from places like summit and such, but they also sell direct which is a bonus! <img src='http://www.canadianhummerclub.com/forum ... e_wink.gif' class='bbc_emoticon' alt='' /> and shipped USPS for us canucks

great post... I am sure I need one now

Thank you !! Excellent post, appreciate the effort.

Thanks for the post! Good info <img src='http://www.canadianhummerclub.com/forum ... ght_on.gif' class='bbc_emoticon' alt=':right_on:' />

No Problem guys! <img src='http://www.canadianhummerclub.com/forum ... rgreen.gif' class='bbc_emoticon' alt=':mrgreen:' />





Workin on the H1 is always fun, you get to use bigger tools

Excellent post and thanks so much for sharing.. it is great when we all can learn from each other's experiences...

No prob Derek <img src='http://www.canadianhummerclub.com/forum ... ght_on.gif' class='bbc_emoticon' alt=':right_on:' /> lots of great little threads and mod writeups to come <img src='http://www.canadianhummerclub.com/forum ... rgreen.gif' class='bbc_emoticon' alt=':mrgreen:' />



So far the balancer has been great, truck starts good, minimal vibration, smooth as a diesel could be