Engine Clacking Solved (unfortunately...)

[Yamaha V6]

Well, I was hoping it was a slack cam chain / tensioner, but it ended up being something a TAD bit worse...

After pulling the intake & covers, and seeing that everything looked totally MARVELOUS (Castrol GTX, baby), I decided to address a whining / bad bearing pulley on the accessories & timing belt. I wasn't totally convinced that the marginal Alt idler pulley & marginal PS idler pulley were the cause, so I started pulling the timing covers off...

Got the top one off, and saw a TON of red / iron dust over everything. Of course, I was like, "Not good". Pulled the rest, and the CPS is COVERED in it. I ended up busting my middle timing cover (of course) in the process too.

I couldn't figure out where this dust was coming from - I mean, it was obviously in the timing area, the T-belt was coated in it & everything. Well, I go to re-align the crank into position to reinstall the belt, and WHOA BABY! The Woodruff Key was mangled, half worn away, and the crank relief area that accepts the key was just as mangled. Faced with almost certain temptation, Sir Galahad rushed back into Castle Antrax to give the 8-score young blondes & brunettes their spankings...

Seriously, I weighed the options, had Woodruff Keys on the shelf, had access to a 3.2L (yet to be pulled from the car), have enough crud to build about 4 3.0L engines, and have a crank sitting on the shelf (from Mark N.). Since I've got the 95 ATX coming in about 2 months or so, I decided to jam a new key in there, and see how far I could get before it totally shreds. At that point, the 89 will likely just get a 3.2L swap before I sell her.

Thought I'd post it - watch those Keys when you do a 60k - make sure they're in good condition.

 

[pjtoledo]

Wow, bad news. Did the woodruff key and crank damage extend in to the timing belt gear? Was the crank bolt still tight? Do you have stock cams and springs? I've 247,500 on my 92, it's time for me to start worrying about this kind of damage.

Perry Toledo,Ohio

 

[Yamaha V6]

Yes, timing gear was frigged. There was considerable "slop", which would attest to the 5-10hp loss I felt I had (which I attributed to an out of time rear head exhaust cam, due to the chain or tensioner). The crank bolt was TIGHT. It took 6 bumps off the (Gen 2) starter to free it.

Stock everything on the block. It's a Mark N. shortblock that I picked up about a year ago, my wrecked 95's original heads (before the blower, from the spun-bearing engine). I threw this engine together this summer to get the 89 on the road. Honestly, I don't remember looking at the key condition, so it may have been good or mangled already - I couldn't tell you. Also couldn't tell you the block mileage, but the rod bearings were good just after installation this summer. It's got about 7k on the replacement powertrain since it was dropped in.

It's had an alt UDP for awhile, and since I had it off, I threw a waterpump UDP on tonight for good measure. It WAS just sitting on the shelf, after all...

 

[shojuan]

You probably already do this but a good reminder for everybody else is after cleaning the woodruff key and crank a bit coat them with a thin layer of a good grease. I used some redline assembly **** I had lying around when I did my 60K front end work. Should help keep crank cancer at bay.

Rick

 

[DavidT]

I don't mean to sound ignorant, but...
What exactly happened? What was the key rubbing? Something had to be rubbing something? Right? Did the hole the key fits in get wallowed out?

 

[Yamaha V6]

Yes, there was play in the key / recess, which buggered the key, opened up the recess, and opened up the keyway in the timing gear as well. Since the old key is smaller than the new one, there is far less slop and movement, but since the recess has opened up, the key replacement is a temporary remedy at best. Since the recess is part of the crankshaft, the crankshaft needs to be replaced to fix it. About the only other "fix" would be to machine a stock recess at 180° from the current one. Then you'd have to intentionally mis-align the timing belt / crank gear placement 180° to have the correct timing.

Since the crank is likely to be replaced, I figure it's just as easy to do a 3.2L swapout at the same time.

 

[pjtoledo]

****, they weld on the crank joournals, why not fill in the keyway and cut it again? Guess you'll save this one for when the cranks start getting hard to find.

Perry Toledo,Ohio

 

[sdpatt]

I had this happen to a lesser degree a couple of 60Ks ago. Fortunately(?), the keyway had cracked under the damper. The damper was loose and the crank was gouged for about half the length of the key under the damper. The timing belt pulley was still tight with no wear on the key of or the grooves in the crank or pulley. The keyway under the damper on the other hand, was cracked in two and nearly sheared from the forces of the damper. The crankshaft was reduced in diameter from this wear and needs to be shimmed to allow the damper to fit tightly. I definitely use the full 126 lb-ft of torque on the damper bolt and use blue Loctite on the washer area of the bolt. I believe that the cause of this was a damper bolt that wasn't fully torqued and had come loose. I'm sorry to hear about your situation I feel your pain.

 

[DavidT]

I believe that the cause of this was a damper bolt that wasn't fully torqued and had come loose

That would make the most sense, except it took six bumps off the starter to loosen it eek!
I believe I need to go in and double check mine. When I did the timing belt recently, I was able to loosen it easily by hand!
BUT
this doesn't make sense to me. The crank pulley won't budge AT ALL without a harmonic balancer puller. SO even if the nut came loose, it seems it would still stay immovable
Is this "crank cancer"? Is crank cancer just (bad) luck of the draw? (nothing can prevent it?)

<small>[ December 30, 2002, 12:14 AM: Message edited by: dkautumna ]</small>

 

[shojuan]

Yamaha V6:
Since the recess is part of the crankshaft, the crankshaft needs to be replaced to fix it.

Fill the keyway with JB-weld.

Rick

 

[Yamaha V6]

I did Rick.

Filled it a little in the recess, then placed the key in, & filled the balance on the outside, let it dry, then put the gear & dampener on later.

I wish I could point to the obvious "loose crank bolt" Scott, but like I mentioned, it was TIGHT.

<small>[ December 30, 2002, 10:11 AM: Message edited by: Yamaha V6 ]</small>

 

[Mike Spataro]

Samething happened on my daughters 93 ATX last year (150K). The engine had lost power and was running very bad. After bringing it to Don Donnalson in Florida for a repair a suspect oil in the spark plug wells, ignition wires and a valve gapping, the problem was the timing gear on the crank. It was destroyed as the keyway slot was badly elongated on the gear. Lucky the crank keyslot was good and he had a replacement timing gear. The engine power was restored after the timing gear fix.
Don said he had never experienced this problem before and I never heard of it listed in the forum.
I did read an article in the SHOACOP website ( Westcoast Club) that showed pics of a 3.2 with the same condition.
Add to the 60K/100K recommendations to inspect your crankshaft key slots!
Good Luck, Mike

 

[haydenm315]

Ugh... where was this topic when I was doing all of my work? Should it be impossible to remove the crank pulley without a puller? Initially I used a puller but if I was careful I could remove the crank pulley without it on subsequent attempts. I didn't notice any play but now I'm scared. No problems so far though.

 

[jthomas68]

haydenm315:
Ugh... where was this topic when I was doing all of my work? Should it be impossible to remove the crank pulley without a puller? Initially I used a puller but if I was careful I could remove the crank pulley without it on subsequent attempts. I didn't notice any play but now I'm scared. No problems so far though.

They all seem to be a bit different.Mine was very hard to get off,it took about 1/2 hour to remove.I did another members,and with the puller,it took about 15 seconds.I do believe it should not be able to be removed by hand,but i don`t have enough experience with multiple SHO`s to say 100%.

 

[luigisho]

It shouldn't be that difficult to remove the pulley if you just had it off. Especially if you lubed and/or sanded the rust off the opening. Now if it's been a while that's a different story.