|
|
|
Hello Everyone:
I recently had my 1989 240 balancer get loose.
I then found that the crank timing gear index pin/key that
indexes to the balancer had sheared of.
So, I bought a new crank timing gear and while starting the
install I noticed that part of the old timing gear index pin / key
was still stuck in the front belt guide / guard.
I tried to get it all out but ended up with what I see as a
curved index pin/key slot - please photo.
It looks like it could cause the timing to be off a least a few
degrees because it appears curved -- or perhaps I am wrong.
That is to say when I go in to align everything , the Timing Index Mark - the little V slot at the top of the belt guard might be off because of
the curve I see in the index key/ pin slot.
Question - does this appear to be significant and should this item be replaced?
Thanks for your input..
|
|
-
|
|
|
I think you'll be fine.
The cam timing is based upon the number of teeth, not the position of the notch in this flange, so the flange will not produce any error.
Ignition timing... I'm trying to recall what it would be in your '89. I know in my '87 it's triggered by the hall effect sensor in the distributor, and the distributor is driven by the intermediate shaft, (with the advance handled by the ignition control unit at the side,) so that too is driven off the cam timing belt.
So, I think the notch is only there to help you get it back together correctly, and as long as you are not off by a whole tooth on the sprocket, you will be fine.
I'm not sure which timing belt you have, but half of them (Volvo, Continental) have the "marks" painted on the back of the belt. If you use those to make sure you have the correct number of teeth between the crank, intermediate, and cam shafts, then you should be all set.
OTOH, if I had a different flange available, I would be tempted to replace it "just to make it right". I'm kind of OCD that way. 8-)
Roger
'87 245 B230F M47 297k miles
'93 945T B230FT 213k miles
'95 850T B5234FT 255k miles
|
|
-
|
|
|
Thanks for your reply. I have ordered another front belt guard from FCP - at $4 - I can be a little less OCD about it.
|
|
-
|
|
It looks like someone hacked an extra "keyway" in that guide washer (belt guard). There should be only ONE cut-out to engage the "nib" on the crank gear/sprocket, and it should be opposite the reference notch in the outer rim. See the upper washer in Art's photo below...
Also, it's not normal for the balancer "get loose", so be sure to torque the bolt to the specified 44 ft lbs followed by another 60° of angle tightening. For that I suggest the rope trick as a crankshaft counter-hold.
In my opinion, sticking anything in the flexplate as a counter-hold is asking for trouble. To say nothing of the needless hassle of getting under the car for access. There have been at least 2 cases reported here of flexplate damage, while dozens have reported rope rick success.
--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
Yes, thanks for your reply.
I just commented to the previous poster that last night I looked into
this and found that the slot that I had marked as where the index key goes
is incorrect and should be as you said opposite the index mark on the belt guide.
Why the repair shop who last changed the belt would put this on incorrectly is
unknown.
Yet the timing is OK.
I guess he just jammed the index key into the wrong slot.
This is why I am doing all of my own repairs now.
Who can you trust.
Anyway , I bought the counter hold tool , new gear and new front guide from FCP.
Still debating the tensioner.
Thanks again.
|
|
-
|
|
It could be the photography, but that guide you show looks odd to me, for more than just the second keyway. Looks dished. When you get your replacement, maybe come back and post how it is different. We have two 89's and the parts in them look like those in our 90 and two 91's, as well as those from the 92 940 in the pic I posted.
--
Art Benstein near Baltimore
“The single biggest problem in communication is the illusion that it has taken place.” George Bernard Shaw
|
|
-
|
|
|
Hi Art:
Here is the image of the new front belt guide.
It's not a great scan but it clearly shows what you were
talking about.
It appears correct.
Regards,
Chuck
|
|
-
|
|
|
Hi Art:
The guide is pretty flat except for the "convex" edge.
Probably because of the scanner I used - some distortion.
What is really strange to me is that the guy who replaced
the timing belt some years ago put this on such that the
balancer index key was in the wrong slot.
The slot he had it in is obviously too small - visually obvious when you
lay the guide against the crank pulley and compare to the outline of
where the index key used to be.
The slot the person had the index key in is about 1 mm too small
for the index key.
I will post an image of the new guide 1357621.
|
|
-
|
|
|
Oh, ok, it makes sense now that you say it was imaged on a scanner. I thought it looked like it had a step in its profile, rather than a smooth shallow dish. What I cannot understand is why someone would go to the trouble to notch out a second keyway, as the keying of this is not important to any function beyond using the small notch on the outer edge to visually indicate TDC when aligned with the rib in the seal carrier casting. And making a second notch surely does not help that function.
TDC is pretty easily verified through the spark plug opening, or if you can trust the crank pulley, that mark on the timing cover. Then the belt is just a matter of counting teeth to locate the other two sprocket keys. Very interesting post.
--
Art Benstein near Baltimore
Give a man a fish and he will eat for a day. Teach him how to fish, and he will sit in a boat and drink beer all day.
|
|
-
|
|
|
Art, the second slot in the guide appears to have factory, I have seen some images where there are 2 slots - -could be wrong though.
Anyway, the index key was broken off and stuck in this the incorrect slot and I messed up the slot a bit trying to get the piece of the key out - so it wasn't that bad looking until I got my needle nose pliers on it.
But now that I have both covers off and the new gear on, I have to time it.
My understanding is that one can simply align all 3 marks - the crank, cam and intermediate shaft with their respective marks and timing is set. Then all that's left is to slide the timing belt on, tighten the tensioner , rotate 720 degrees a few times to verify alignment, if all 3 are aligned correctly, run 5- minutes, loosen tensioner to re-adjust for slack in new belt and you're done - -our am I wrong.....?
|
|
-
|
|
|
You got the picture - not rocket science. Use the three timing marks on the sprockets/engine case and ignore the painted marks on the new belt.
Check out this link for good photos:
http://www.brickboard.com/FAQ/700-900/B230FTimingBeltAlignment.htm
|
|
-
|
|
|
Thanks for the reply.
I've read all sorts of how-to on the 240 timing belt replacement.
Like leaving the old belt on and doing this and that and jumping through hoops - or -
Taking the cam gear and balancer gear off - none of this seemed reasonable.
But I came across this one that I referred to that seemed to make more
sense than the others.
Simple and efficient - for simple minded guy like me - just perfect.
Line up all 3 marks and slap the belt on.
Thanks again.
|
|
-
|
|
|
After reading your reply two posts up I realized you may have taken my illustrated photo as advice for installing t-belts. The original intent there was to provide a means for someone who questioned his I-shaft lineup to verify the timing after everything was all together. He could simply remove the upper cover, instead of going through the removal of the crank pulley to expose the mark under the bottom cover. Providing that photo in your thread was more of a confirmation the timing is just a tooth-count relationship; that using the marks on the belt works well when installing, but pretty much useless once the belt has gone 'round a few times.
What still nags at me about your pictures is that second notch. What if, instead of this being a factory mistake, it was actually punched out by the nub on the sprocket being forced on during the torquing of the crank pulley bolt with the guide misaligned. It just doesn't look "factory" to me. Did you get your replacement guide? Just one notch?
--
Art Benstein near Baltimore
A bicycle can't stand alone because it is two-tired.
|
|
-
|
|
|
Hi Art:
I was not referring to your post. I had read a how to guide written by someone and the method was tedious and called for what I thought were unnecessary steps. Another I read recommended removing the cam gear and other over the top tasks to get the job done.
But , I was not referring to your post in any way.
The method you listed would be quite helpful if one did not want to remove
everything as I have already done.
I have not yet received my new guide from FCP - I opted for the "Free" shipping method which is I guess coming by mule train.
Regarding the extra slot, I have seen other photos on the web where the guide did indeed have 2 slots. I don't know why they would add the extra slot but I don't think the index key pushed it's way through (as the guide was not distorted or ripped looking - except where I got after it with pliers) - though anything is possible when it comes to my cars.
I will post a nice photo when I get the guide and tensioner.
Regards,
Chuck
|
|
-
|
|
|
Doesn't look like a big deal. Unless the slop in the key slot allows the timing notch to wander more than half of a sprocket tooth off, which it doesn't appear to be the case, I don't see how it could cause you any grief. Just make sure you haven't induced any sort of jagged burr that could cut into the belt over time - sand it smooth if there is anything.
|
|
-
|
|
|
Thanks for your reply.
After looking at more info about this, I found that the fellow
who worked on this car last used the slot I have marked in the image
as the place where index key goes through to the balancer is incorrect.
The slot opposite is where the index key should go.
Looking at the jagged slot I was questioning - I found the width too narrow
to accept the index key from the crank timing gear.
Yet the car is in time.
So, how he timed this I don't know, unless he just slipped the old belt
off and slipped the new one on and smashed the index key through
the slot I have show as the place for the index key (incorrectly).
If you look at any image of a new timing belt guide you will see
that the index key slot is opposite the timing notch cutout in the belt guard.
|
|
|
|
|
