After over a year of tracking down an engine noise, I finally found it! I thought it was the water pump, but It was a loose harmonic balancer on my 261! It came off in my hands when I was checking my belts.
Question: without taking my front end, AC and radiator off. Can I put a new one on?
I assume I can use a 2x4 and 3lbs hammer to “wack it” on.
If you choose that method (about #13 on a choice of 1 to 10) be sure to drop the inspection cover off the bell housing and drive a hardwood wedge tightly between the pressure plate and the back of the bell housing. That will prevent damage to the front of the #3 main bearing thrust face while you're hammering. If the balancer is loose enough to be noisy, the crankshaft snout will also be worn and a new balancer will loosen up quickly. You really need to drill and tap the crank snout for a center bolt to keep the new balancer tight and use green LocTite stud & bearing mount on the assembly when you install it. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
HRL is giving it to you straight. That balancer was wobbling and a new balancer is likely to have the same issue. The correct way to solve the issue is to drill the snout and use a balancer bolt for a small block chevy. It sucks I know, and its going to cost a couple of bucks, but once done, its done. You really don't want the new balancer coming off while you are driving. That kind of damage might be even more expensive.
I ordered all the stuff I needed, but still trying to figure out which woodruff key I need. When my engine was rebuilt, they but a key in that was incorrect and just slide out of the way. I’m considering using the Square stuff and cutting to size.
Additional question: can I reuse my old balancer with a new key and bolted on or should I install a new balancer, key, snd bolted on?
If the slot in the crank is wallowed out, you will have to sort out an alternate retention method. May have to bite the bullet and use a pin kit to pin the crank. Lets hope that is not the case.
As for reusing the balancer, I myself would not. The retention slot in the balancer is likely damaged. Although if you are a good machinist (am I am not) and have the proper equipment you may be able to machine a new retention slot. A replacement balancer is just not that much money and I would hate to go to all that trouble, get it all back together only to discover the rubber gasket between the halves is bad, or some other issue.
I have another balancer here (thanks to a bolter here), I was just curious. My key slot/journal is still ok, just trying to figure out the size if anyone happens to know it.
Chris - The original woodruff key for your application is GM# 106751 (Key, woodruff - 3/16" thick x 9/32" tall x 3/4" long #9). If you search the web for GM# 106751 you will find lots of sellers/sources offering them, either NOS or new replacements with prices ranging from as little as $1.15 (not counting shipping) to upwards of $9 a piece (also not counting shipping - OUCH).
BTW - It's the same key used for the crank and cam gears if I'm reading things correctly in the "Parts" resource books I have.
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
A snug-fitting woodruff key is an absolute necessity. Even with a bolt holding the balancer tight against the timing gear, a sloppy fit between the balancer and the key will unscrew the bolt. At 2000 RPM the balancer will be trying to move back and forth 66 times a second due relative motion between the balancer and the key. A worn key, and/or extra clearance between the slot and the key will make it impossible for a center bolt to stay tight. "No exceptions- - - - -no excuses!" Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Question is it possible to drill for a bolt with the balancer still on the crank.The one I took off a parts engine was on there good and can you use the bolt after modifying for it to install the harmonic balancer or do you still have to pound it on.
1. I don't think you'd want to try drilling with the balancer installed. The drill guide wouldn't fit on the nose of the crank and you likely would get the hole mis-aligned. Although you could fabricate a drill guide that inserted into the balancer instead of over the crank snout. 2. It's not advisable to use the bolt to install the balancer, as it's likely to strip or damage the threads in the crank. The proper way is to use an installer that threads into the crank (keeping those threads stationary) and pushes the balancer on. LIKE THIS.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
I have been using the same Moroso tool for pretty close to 40 years. Its a good investment. And once you use it for the first time, you will understand why its better then using the balancer bolt to try and seat the balancer against the crank gear.
Once upon a time- - - - -long ago- - - -I used to make and sell a kit to accurately drill and tap a crankshaft snout, and it included an ACME thread balancer installer with a Torrington bearing thrust collar, all for the princely sum of $75.00. I finally had to give it up- - - - -even with a 2-page step by step instruction sheet to go by, people just couldn't seem the figure out how to use it! I've probably drilled and tapped a hundred crankshafts, all freehand, and never had a problem doing it. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Interestingly enough, if you purchase a real balancer install tool, you can purchase the below sleeve which installs on the balancer installer and you have yourself a proper crank gear installer.
I replaced a balancer on my 250 while in the truck ( '37 ). It was tight fit, pretty ssure I had the radiator out of the way. The old one pulled off with a balancer removal tool. The new was placed in an oven and heated to 200 degrees while the truck sat outside for a hour or so in 20 degree temps. While the truck was still in the cold, I had on heavy gloves, grabbed the balancer out of the oven and made a run for the truck. In one quick motion I shoved the balancer on the crank and made it about 80% or more onto the crank before it got stuck. A wood block and hammer seated it fairly quick before cooling completely.
The bolt is nothing but a stop, it doesn't hold the balancer to crank, the press fit and key do that. The washer and bolt just keep it from coming forward. The added bonus is you can use the threaded hole for installing. Pontiac's use a 5/8-18 bolt torqued to 160ft lbs, they will stilll crack the keyway if the press fit is not tight.
If you use the hole for installing the balancer, insert a stud into the crank and use a nut, washer, and oil to push the balancer on. This puts all the force on the nut and external threads. The stud will have the full length of internal threads to hold on to, if you use a bolt you are pulling a lot on just a few threads while starting the install.
Well, I got the hole drilled, but struggling with threading it. It took 1 hour to thread 3/8”! I’m reduced to 1/4 turn at a time due to the front cross member.
Time for more oil and a few more cranks!
More to follow!
Update: despite having a new 7/16 x 20 tap I struggled to get it threaded to the correct depth. I pulled out my great great grandfathers tap and I had no problems tapping the hole to 1”! Tomorrow I will install the balancer!
Here is my step by step. 1. Remove grill, lower gravel pan, and top where hood latches. 2. Unbolt radiator (I used a 2x4 to hold it up so I didn’t have to drain coolant). 3. Using collar with smaller guide drill with xxxx bit (1-1 1/4” depth) 4. Using collar drill a 13/32 hole to same depth 5. Using collar (threaded) tap hole to 7/16 x20 to hole depth 6. Using a harmonic balancer installer, press balancer onto crank shaft. 7. Reassemble the million bolts holding the front end together!
I will start posting pictures shortly. I also have manufacturer’s instructions if anyone needs them.
4. Using collar drill a 7/16 hole to same depth 5. Using collar (threaded) tap hole to 7/16 x20 to hole depth
If the hole is drilled to 7/16 won't that be too big for the tap?
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
I’m sure it’s a typo but the correct drill size to tap 7/16-20 threads is 13/32”.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
~ Craig 1958 Viking 4400 "The Book of Thor" Read the story in the DITY 1960 Chevrolet C10 "A Family Heirloom" Follow the story in the DITY Gallery '59 Apache 31, 327 V8 (0.030 over), Muncie M20 4 Speed, GM 10 Bolt Rear... long term project (30 years and counting)
If you don't like driving yourTruck, you won't drive yourTruck..| Living life in the SLOW lane
Measure again. .005" might be OK- - - - -.050" will never fit!
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Don't let SWMBO see you put it in her oven to expand it a little.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
It’s not a slip fit, it’s an interference fit for certain. Also, I I will give you my two cents here, and you can take it with how ever many grains of salt as you wish, lol. I would not heat this balancer. The 235/261 balancer is essentially comprised of two parts the hub and the balancer (not including the pully, three including the pully). The two parts are riveted together with a formed rubber spacer in between the two parts. It’s pretty durable. I don't know what happens to the now 60 year old rubber spacer when its heated in an oven. Might be ok, then again, it might not. Why chance it.
With the crank drilled and tapped, you really should not need to do that. I have rebuilt a couple dozen of these motors over the years and not once have I ever heated a balancer to get it on and I have never had a failure. so I think you should just install it with the proper tool, install a balancer bolt, and you should be good to go!
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
My 20 something son's car. He wanted to rebuild a 57 chevy with a 261 so he got my last Canadian 261 block, and every other spare part I had, lol, and we rebuilt it. He likes his Irish heritage so wanted a green. Found a really stellar green called Galactic Green on the Urechem website. Nice paint at reasonable prices. It will certainly catch your eye, lol.
Make sure you clean the snout, bore and keyway real well. I usually run a file thru the keyway (both balancer and snout) to make sure there are no burrs. Also check to see how the key fits, again on both. If it’s a new key, I break the corners with a file so they are not sharp.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
Heating just the balancer snout, not the whole thing, with a Propane torch doesn't cause any problems. I use a rosebud tip on an acetylene torch, and warm up the hub until a drop of water sizzles away quickly, and then tap the balancer on with a big dead blow mallet. It usually bottoms out with just a few quick hits. If not, a piece of all-thread rod and a nut and a few fender washers complete the installation. Obviously, that's after the crank snout has been drilled and tapped. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
It’s not as bad as I thought, but I will say if it’s in the truck, it become more exciting.
List of items you need. The collar to keep the bits straight 2 bits that come with it 1 7/16 x 20 tap 7/16 x20 bolt with thick washer (kit) Green loctite Rent a harmonic balancer tool (oReillys for $28 rental) The balancer tool requires a 1 1/4” open end wrench as it’s too deep for a socket. Something to ensure pulley alignment (bore lazer for sights guns works great!)
Respond if you have troubles!
Chris
Edit: my balancer is aligned. Once I recover from a knee injection, I will install the bolt.
Thanks Chris! I've ordered the collar, drill bit, tap,... I'll need to pick up some green Loctite. I have complete access since the engine is just sitting in the open frame.
~ John in Utah 1946 1/2Ton w/4-speed manual transmission w/1960 235 engine Here We Go Follow in his DITY Bay
- If you think about it, it has been one year ago today!
So I was told to use the green loctite on the snout… not the bolt. I never used it. I did however add 2 drops of blue loctite on the threads along with a torqued lock washer as an extra precaution as I don’t see taking it off again.
If you have questions, it’s best to start a new thread so your questions don’t get lost in this one.
Personally I would use blue Loctite. Green is a low strength wicking formula; good if you already have something fastened together, it will wick into the threads. Blue is medium strength, can be removed without heat if needed. Blue comes in 242 and 243 formulas ; 243 is more oil resistant for oily situations. Best is be sure everything is clean, and let it cure before using.
Geoff
1955 2nd Series 3600 235 cid, 4 sp. - Current 1979 Chevy K10 350 cid 4 sp -Sold 1955 2nd Series Wide Window 283 cid 3 sp - Totaled
If it makes any difference to anyone, I have been drilling and tapping the snouts on all my cranks and installing the balancer bolt since the middle 1980s. I have never used anything on the snout. No loctite or any other adhesive or locking chemical. A little lubrication. The bolt goes in dry, use the thick spacer and the lock washer. I rev my 235 and 261 motors up more than most I guess, some as high as 5800-6000 rpm. I have never ever ever had a bolt come loose. The factory bolts on the V8 motors do not use anything on the bolt either. Not saying it could not happen, but it has not happened to me. So I am not totally sold on the need for locktite on the snout or the bolt.
I went to take a test drive today after I got her fully assembled. When I started her up, I have a rubbing sound that changes with RPMs. I ran engine for a few seconds and turned it off. I assume it’s one of 2 issues.
1. Despite pulleys aligned, Balancer is too far in.
2. Something internal is rubbing (I originally tried to tap the balancer on but stopped after a few hits)
Thoughts? I assume it’s #1
Edit: my neighbor started my truck while I was under the hood and the sound is gone!
