Hey everybody, I've been slowly rebuilding my '79 Pickup with the original 20r, and I've recently discovered something new with it.

About 4 months ago, I parked it because I heard what I thought was a rod knock. And I will not take any chances with the one item of significant-ish value I own. I'm admittedly poor so I can't afford to have a rod throw.

Well two days ago, I finally had enough money saved up to pull the entire engine apart, inspect everything for any visible signs of wear, to no avail. I took the head off, my valves look almost new, there is of course some carbon, but this truck has been very well taken care of so I wasn't surprised. No pitting, checked the valves for wear, and straightness, they're all perfect... I could use a couple shims for my rocker arms, cause there is some slight misalignment on the top of two of my exhaust valves (which I assume is from my previous exhaust leak) but for now, I am going to choose to ignore it until I can afford to replace the entire assembly for good measure, or possibly shim the two misaligned arms.

Not to mention, when the "knocking" started, I did a compression test, and got 155+ in every cylinder. Which is terrific for an engine that just hit 200k, even though I got my 88 22r to well over 500k miles until two of my valves had holes in them, and I started to lose power. Still put another 50k on after I replaced the head with a used one. Without ever having a service done on the bottom end. Plus my current truck was owned by my boss who more than babied it. And I treat it like it's my baby. I don't honestly think it's ever hit redline. So here's to hoping it stays as sound as it is.

At this point I'm just rambling but what I did next is rotate the bottom end and test each piston for any play by pushing down on them (HARD) while they were on their downward stroke, and there was literally ZERO play. Which is another great sign, no noticeable upward or downward play in either the wrist pins or connecting rod bearings.

I took off the oil pan, and tried to wiggle the bottoms of the rods on the crankshaft, and used my feeler gauge but I was still within factory spec. I could barely move them.

All good so far. So right before I go to remove the rod end caps to plasti-gauge my clearances on the rod bearings, and the mains, I went to twist the engine by hand and instead of turning, I felt the crankshaft pulley shift a little! So I poke my head up just barely enough to see that the damn pulley doesn't even have a bolt in it... I can't believe it.

So I'm assuming that when my boss replaced the timing chain, he never torqued it back down properly and it eventually worked itself loose. I can't get in there today to get some good pictures of the damage, but I'm pretty sure that if it has any play back and forth without the crank itself moving, then it's more than likely a squished key, and/or key way.

I'm kind of worried I'm going to need a new crank but I can't help but think there is some "ghetto" rig out there to get me by for a year or so until I can just drop a couple thousand or so on a full rebuild.

It turned out, when the truck was just idling, the pulley was just wobbling and clunking. I can't believe it. So at least I get to put in all new seals on my engine! Haha...

Anyway, I'm hoping someone has something to say other than the obvious answer of "Replace the crank, pulley, and key.

NO. If that is your suggestion, please exit the post because I'm not stupid enough to not know for a fact that is the best solution.

I am poor people, not a moron. So any poor-man solution you can throw my way I will gladly take into consideration.

I'll post pictures of the damage tomorrow. But I can tell you now, it isn't the slightest bit of a press fit any more.

Thanks in advance!

 

My point is, this engine doesn't even really come close to 100 horsepower, especially the way I drive. So while a turbo supra might not be able to last with lets say drilling out the keyway on the pulley and the crank at the same time to 1/2 inch, and stuffed a steel dowel in it, and replaced the bolt, over the top, with loctite, my slow ass toyota pickup might just stand a chance. I've heard of some success with a couple methods but I have yet to hear about other modifications. And definitely not on the 20r.

 

Get a bigger woodruff key, get a dremel out, enlarge the keyways carefully until the key fits snuggly maybe even with a little persuasion, put the correct bolt on there, make sure the threads are clean, put a very little amount of thread lock on 1 or 2 threads and tighten with impact gun. Done it before on a beater and it lasted much abuse.

 

I'm actually in Nevada right now, so an impact might be out of the question cause I don't have my tools here. But I'll torque it as much as I can, probably around 150lbs and make a quick run to the shop down the road and see if they can impact it on for me. But that is a good idea. I'm just curious what key might work, I'll do some digging around, but if anyone has any suggestions, that would be very helpful. I'm a couple weeks from even putting it all back together so I have time to figure this out the right way.

Thanks for the idea gilles, not the first time you've offered good advice. I'll post back here tomorrow with an update on the condition of the crank and pulley, but it has roughly a quarter inch of play between the two, very curious to see how bad it is.

 

JB Weld to take up the slack??

 

No problem Wid! Hope it works out for you, but a 1/4 inch that is a lot! If you want a cheap woodruff key, go to a junkyard, find a 88-00 D-series civic or 90-01 integra, pull off the cam gear and there will be a key, it is as large as the key on the stock 22r crank pulley though.

 

Well I'm sure that might work but that's still a lot of torque for jb weld.

But I have some good news, I pulled the balancer off today and it isn't nearly as bad as I first thought. Luckily I didn't drive more than maybe 300-400 miles after the "knocking" started.

The key way on the harmonic balancer is a nice tight fit, and when I flipped key over on the good flat side it actually feels pretty snug most of the way through. I think I'm going to just order a new key and see how snug it all fits together but I think I got pretty lucky on this one. Only the key on the round side has any noticeable wear.

Pictures when I get home.

 

Here you can see noticeable wear at the center of the Key.



Here, you can see the wear at the top of the key, yet still minimal.



Just another angle to show the wear a little better.



I'm pretty relieved though, it could have been much worse. I suppose these old 20r's are a little stronger than I anticipated. I was gearing up for a completely mangled Key Way.

I'll keep every one posted on how the re-install goes. Thank you for the tips, cause I may still need them. But as of now, it seems like a new key will be a nice tight fit.