Hi,
I just did the water pump, timing belt and front seals on my 88 740t w/270k. Everything was going well until it starting making a helicopter noise on the way home. I thought, "I'll check it out when we get home." Well, I lost the power steering, alternator and it started to heat up so I had to pull over. Evidently I did not torque the crank pulley properly after putting everything else back together. I have't had time to look at it yet but I'm sure I sheared off the pin that the pulley meshes into. I looked in the faq's and this seems to be a real bit of a problem. I read about filing down the head of a bolt and another technique that requires lots of superglue, drills bits and other tools. Has any one else had this happen? Its a shame that the only time the car has let me down is a result of my own oversight. What to do? Your help would be much appreciated.

J.Studer

Pittsburgh

I did get my 88 taken apart and found that the tab on the bottom timing gear was indeed sheared off. Lucky for me I have a spare parts engine in the garage...in ohio. The pulley will without a doubt be fastened properly this time. Thanks for all of your input.

J.Studer

Seriously...my $0.02 worth: ♂

The setup is relatively simple, as I recall. You've already been in there once to replace the timing belt, so it's familar territory.

There may or may not be damage to the pulley or the shaft, depending on what materials Volvo specified during construction.

The pulley, as you know, is a tight, almost 'press-on' fit on the shaft. It has to fit a key that's set into the shaft.

Depending on exactly what occurred when things came loose, the pulley may just have slipped forward and you may find no damage to anything.

If that's the case, put it back together, use a GRADE 8 stainless stel bolt with just a dab of LocTite on the threads, and torque and tighten it as outlined elsewhere in the posts below.

Using a lesser quality bolt is asking to do the same job over again in the near future. You're putting a lot of torque to this bolt, and you want it to stay put until you decide it needs to come off again.

If something has broken, it is probably the pulley that came loose. If damage isn't readily evident, be sure you clean it thoroughly and examine the keyway under magnification. For the pulley to have slipped loose without at least cracking its keyway would be a miracle, but still possible.

Whether or not you find damage to the pulley, be sure to check out the keyway in the shaft. It's entirely possible that the pulley twisted as it came off and either broke the key or even actually broke a chunck out of the keyway in the shaft. I'm sure that the Volvo engineers are as good as any others at specifying softer material for the key, to prevent this happening, but stange things have managed to find their ways into machanical structures before!

Again, regardless of the apparent damage to the pulley, make sure you inspect the keyway.

And yes, putting in a new oil seal while you have it apart is a good idea.

Good luck with it...actually this thread is so old you surely have it fixed by now!

Steve

Just a silly question...Why do we drive on the Parkway and park on the Driveway? Isn't that the wrong way around???

From straightdope.com

Dear Cecil:

Please answer this question--I've been lying awake nights just wondering. Why do we drive on the parkway and park in the driveway? --Deidra N., Baltimore

Dear Deidra:

Believe it or not, this is the third time I've gotten this question in as many months. It must be the sunspots.

Let's get one thing cleared up right off the bat: you can drive on the driveway. Indeed, if you'll permit me to wax philosophical for a moment, this is the very essence of drivewayness--to enable you to drive from the street to your garage. Moreover, you can park on the parkway, if you're willing to risk the wrath of the law. I don't know that this clarifies things much, but it seemed like a point worth making.

I think the crux of the issue, however--I love using words like crux--is the dual meaning of "park."

Park in the sense of tended greenery and park in the sense of stowing your vehicle, though deriving from the same root, diverged in meaning long ago. In Old French, a parc was an enclosure. To this day a military park means an area where vehicles are stored and serviced. As early as 1812 there was a verb "to park," meaning to store one's howitzers in a military park. This carried over to carriages and ultimately to any sort of vehicle.

Our notion of landscaped parks, meanwhile, derives from the medieval practice of enclosing game preserves for the use of the aristocracy. The term was later applied to the grounds around a country estate, then to royal parks in London to which the proles were grudgingly admitted, and finally to any landscaped public grounds. The idea of enclosure is still evident in expressions like "ball park," for an enclosed playing field. Any more questions, smart stuff?

http://www.straightdope.com/classics/a2_080.html
--
700/900 FAQ and now Map your 700/900!

Thanks for all of your input. I'll take things apart this week when I have some time off. One question I still have though is whether I will need to get a new bottom timing gear or just a woodruff pin? I'm sure this will become more clear once I take things apart but I wanted to say thank you for your responses. And just for the record, the rotation of the engine will undo the crank bolt.
Thanks again,

J.Studer

Just a word of warning and this might sound silly but it has happened to me and cost a pretty penny i can assure you. Make very sure that if you are replacing the bottom cog that it is the same size as the old one. If it is not then you run the risk of wrecking the valves and to have that fixed is not cheep.

I replaced the cog on the main drive shaft (just behind the main drive belt wheel) in the summer and the garage put in the wrong one and when they realised what they had done they made me pay for it saying that it was not my fault! I didn't even get the damn car out of there! Was not impressed! Also whilst you have everything open make sure that the balance axle belt is in good condition as if this goes (this was the next thing to fail) it can wreck the entire engine. In mine it mean good bye and good night to all 16 valves and a cylinder! It is now cheeper to buy another engine than to repair the current one.

I don't recall a woodruff key.....I think just a new bottom gear.
The harmonic balancer/timing mark keys to the sheared knob on the crank gear. I think just the nob may have gone away. Still, you won't know until you take it apart.

Well, worst case is replace the crank timing gear and reattach everything and this time use a harmonic balancer holder, torque to 45ft lbs and then 60 degrees more angle tighten.

I've never had one come loose that was properly torqued. I HAVE had harmonic balancers fail, however, and that has nothing to do with torquing. Generally the balancers fail soft; losing the timing marks even though the engine is timed properly.

When you put the balancer back on, take some white paint or chalk or paint stick and draw a line across the rubber boundary between the inner and outer iron parts so you can SEE if the outer pulley moves relative to the inner metal casting.

It wouldn't hurt to put a new seal on the crank end when you replace the crank gear if you think the balancer did some damage.....

there has got to be another issue...i mean as i recall the bolt on the pully is threaded in such a way as to be constantly forced on by the rotation of the crank...how can the thing come loose on its own??? could you have never seated the pully into the woodruff key on the crank? I was paranoit and put some red locktight on mine...has never been an issue taking it off again...good luck

No it's not constantly forced on by the rotation of the crank - if you consider that the crank rotates clockwise, such that if you block a breaker bar and bump the starter you can crack it loose, it becomes obvious that the stationary inertia of the pulley - along with the drag of the water pump, alternator, p/s pump, a/c compressor, & belts - would work the bolt out if it's loose. It must - I repeat, MUST - be tightened properly. There is a very good reason the torque spec is so damned high on that bolt, it's because it needs to be to keep it on there - and because it also serves to keep the harmonic balancer from rotating independently of the timing belt pulley and shearing the pin off the pulley. This question was beat to death a few weeks ago, was it not?
--
Chris, Dartmouth NS Canada 70 M-B 280SE, 83 245DL, 84 244 turbo, 90 780 turbo, 92 VW Golf, 90 740 Rex/Regina

I still don't see how the "stationary enertia of the pully" or the drag of the water pump or anything eles that is driven off of the crank pully can effect this matter...the pully sits in a key that fits into the crank....this means that even with the pully bolt completely off you can turn the pully and the crank so long as the keys mesh...this is the very point of the key....now I see that possibly the stationary enertia of the BOLT itself could have this effect, but there is not that much mass there and the diameter of the bolt head is not that great...additionally cranks don't change speed that quickly....that is barring high speed engine lock-up...in which case the bolt would want to continue spinning clockwise...aka tightening...now unless you are prepared to tell me that the old redblock revs so quickly as to out pace the accelleration of the bolt...I still ain't buyin it...please elaborate further.

Tighten it however you wish, however much you want, I'm not here to argue with you. However I'd point out that the balancer on a B230 is keyed to the timing belt pulley, not to the shaft. The timing pulley is in turn keyed to the shaft. Here's a site with the best photo I could find of that keyway:

http://www.actionsalvage.com/detail.asp?product_id=309196

Perhaps you are arguing the point based on experience with a B21 with its pulley which is, as you describe, keyed directly to the shaft if I recall correctly?

When it's so easy to just do it right in the first place, I can't understand why one would recommend taking a shortcut when time & time again experience has shown (and to plenty of people on this site), that it will result in failure.
Just my $0.02. I'll bow out of this thread now.

Edit: sorry, the address above is for the 16v - here's the 8v version (same principle though):
http://www.actionsalvage.com/detail.asp?product_id=309188
--
Chris, Dartmouth NS Canada 70 M-B 280SE, 83 245DL, 84 244 turbo, 90 780 turbo, 92 VW Golf, 90 740 Rex/Regina

ok...

"...i mean as i recall the bolt on the pully is threaded in such a way as to be constantly forced on by the rotation of the crank...how can the thing come loose on its own???"

I believe the crank rotation would tend to loosen an improperly torqued pulley bolt. That's why it loosens with the braced breaker bar-starter "trick".

That's also why I always suggest the "rope method" as the only crank holding tool alternative that allows for the correct bolt tightening torque (44 ft lbs, then an additional 60° angle tightening).
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

I've seen older B230 engines throw crank pulleys because they have too much endplay in the crankshaft.

I'm not sure I understand - do you mean the vibration just prematurely wears out the damper?
--
Chris, Dartmouth NS Canada 70 M-B 280SE, 83 245DL, 84 244 turbo, 90 780 turbo, 92 VW Golf, 90 740 Rex/Regina

Not too serious. Junkyard or local Volvo indie shop - any junked B230 - and there are plenty of them out there - has the timing pulley you need, and it just slides off the crankshaft (though sometimes it needs a little persuasion). Unfortunately this means you'll have to tackle the timing belt again, though you may be able to slide the old one out & the new one in without disturbing your timing - just loosen the tensioner nut, pull a little slack into the belt & retighten, then give it a try. And next time make sure that pulley bolt gets tightened to spec...
--
Chris, Dartmouth NS Canada 70 M-B 280SE, 83 245DL, 84 244 turbo, 90 780 turbo, 92 VW Golf, 90 740 Rex/Regina