Older F Harmonic Balancer (Crankshaft pulley) Question (1 Viewer)

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I've been staring at my F135 engine harmonic balancer since I got it, wondering why it appears to wobble a bit. Took it by my mechanic/friend, who grabbed it, and said that it appeared to be tightly in place, but pointed out that it had an abnormally small pulley groove in it, and an abnormally small fan belt. Which, he observed, went with the GM alternator that someone had installed, using a variety of broken brackets.

Well, I'm wondering how someone got a smaller than normal pulley onto the harmonic balancer, and I'm thinking that maybe I need a replacement, especially since my plan is to put a Landcruiser alternator on there with properly fitting brackets. The whole shebang: alternator pulley, water pump pulley, and crankshaft pulley, does not line up entirely correctly, so I can only imagine that the smaller than normal fan belt is stressed by this and it is only a matter of time before something breaks.

So, I was talking with Steve C. the Poser this morning about his stash, and what might be in it, and we talked about pressed on harmonic balancers and handcrank nuts and so forth, and he suggested I look at my older engine manuals to make sure we are all talking about the proper replacement.

And so, I did. I first looked at the 62 manual. Then the 64. And I saw this. What the hell, I'm thinking. Something's missing here. There's a pulley, but no Harmonic Balancer!
F135hb62 (Small).jpg
 
So I then went to the 66 engine manual (yes, I collect them now). This time it looks like this. I went out and stared at my 45 with the wobbly balancer, and it looked like this, too. Except there is about 1 inch of space between the timing gear cover and the back of the HB. WTF, they didn't press it on all the way so they could line it up with the GM alternator pulley, I guess. Well, no wonder it wobbles.

Well, I need to ask, did they ever just have a pulley for a crankshaft pulley, without the weight of a HB? or is the early manual just drawn wrong? What is correct for my 9/64 engine? Are later F Harmonic balancers (like for my 155 F) the same, and therefore interchangable, or do I need to do something else?
F135hb66 (Small).jpg
 
Mine (5/64) is original as far as I know. I do have a hamonic balancer, but it kind of looks like it's 2 pieces? I've never looked at it very closely, but it looks like there is a front half that fits over an inner piece? That could certainly be a source of wobble if it comes apart or delaminates?

FWIW, my crank pulley lines up perfectly with the water pump, and pretty good with the non-stock alternator (through judicious use of spacers). If your water pump and crank pulleys don't line up, I'd start there.
 
IDave said:
Well, I need to ask, did they ever just have a pulley for a crankshaft pulley, without the weight of a HB?

Yep, that's the way they were, nothing but a pulley. The '64 motor I have is the same way, never checked the engine number so it could be earlier.
 
I dont think the older ones will change out. Pressed on has no nut, I think, while all later ones ave the big ass nut and recessed pulley. 65swb would know or maybe chef? I would fix it ASAP as it can be helping anything in there.
 
Well, when did the big ass nut come in there? Even my F155 appears to have been pressed on, at least it looks that way from this 1972 engine manual....
F135hb72 (Small).jpg
 
All are pressed on to some extent. as I understand it, the early to mid 60s were a true pressed on pulley with no nut while the late 60s (maybe '68 and up) are pressed on with a nut. I am far from an expert on the very early stuff. I would consult the pimp.
 
Press on to ~ March/April of 1969, anything after that should have the nut.
 
OK, I think I just figured out part of this: the engine I currently have in the 71 was a replacement "Low Milage" Japanese that I got from SOR. It has a low Engine number (278830) which would indicate that it is probably pre69. Maybe one of those rare F145s. It is definitely not an F135. So, maybe it is a press-on, and my original was not. (I checked out the original engine's crank, which definitely has a threaded end. But I can't find a harmonic balancer or nut for the SOR engine. Can't remember if I reused it or not. Ahhggh.)
 
Press on crank pulleys ran thru sept 69. 64 and older had a narrow pulley with no balancer. Ranger from this board has one on his 62. I am picking up a good 64 F135 this week with the non-balancer pulley. Not too hard to swap out to a balancer type, if that's what you're after.

Keep in mind that early press on balancers ALSO ran a narrow pulley, as well as a narrow pulley on the alternator and water pump. I have some of them also, and don't necessarily worry about using them. As long as all three match, that is what matters, IMO.

Wobbles are a whole other story!
 
Ah-ha. Well then. Perhaps all I was worried about is nothing. My mechanic has probably never seen the early pulley/HBs. The wobble of the HB is visible, but there is no laxity or movement if one tries to move it by hand when the engine is stopped, and he didn't worry so much about that as the slight misalignment of the water pump (wider pulley) and the slightly larger misalignment at the alternator. Maybe what I need is the proper alternator and waterpump pulleys, and to repress the crankshaft pulley. How does that sound, Mark?
 
if it were me i would tap the crank and put a bolt into the crankbefor that HB Falls off as you are driving down the road and it falls off. Dont ask how i know. its easy pull the Rad, BIB, motor mounts jack up the motor and drill out the crank for like a 7/16 fine thread tap. put it all back in and your off.
 
rogersfj401969 said:
if it were me i would tap the crank and put a bolt into the crankbefor that HB Falls off as you are driving down the road and it falls off. Dont ask how i know. its easy pull the Rad, BIB, motor mounts jack up the motor and drill out the crank for like a 7/16 fine thread tap. put it all back in and your off.

Too funny Ian. I also did the parking lot R&R thing, minus the drilling, at school when I was 24 or 25. Then I milled the claw off altogether, drilled and tapped the crank.
 
Good idear :D
 
Pulley comparison:
pulley comparison.JPG
 
Those are WP pulleys, right? So it isn't just the width of the pulley groove, but where it holds the pulley relative to the fan (the older, narrower pulley is closer to the fan), because of the depth of the cup. Are the WP themselves significantly different? Because it seems like that would move the groove out from the engine, relative to a newer pulley, and affect where you have the crankshaft pulley to align things, right?
 
Well, I didn't take the pic I prolly should have Dave, but the answer is no. I had the pumps and pulleys on a platform side by side, and the centerline of the two pulleys is the same. The smaller groove pulley goes with the 66 and older water pump; the larger with the 67-74 style. Does that make sense?
 
I will try to snap a pic of mine tonight for you. the pulleys will line up but you need to run the smaller 17/32" belt rather than the 22/32".
 
Makes sense, but what I am wondering is, are the water pumps different in height?

I have no clue what water pump my PO put on. If it is a later (67 on) pump, will that screw up my pulley alignment if I use an earlier pump pulley?
 
Considering that you don't even know if your HB is on all the way, that's hard to say Dave!
 

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