Camshaft sprocket locating pin?

motman · Postby **motman** » 14 Nov 2013 18:16

I'm going to see if I can slacken the sprocket and remove/cut/saw the dowl and get it out.
If not then its going to be a chain off job which I will use as an excuse to put a full chain kit on it
Thanks for all the help so far everyone!

Beans · Postby **Beans** » 14 Nov 2013 18:49

Why would you do that?
(see my remark a bit further up)

<center>

1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
[url="http://www.tr7beans.blogspot.com/"]My full Weblog[/url]</center>

motman · Postby **motman** » 14 Nov 2013 18:59

The bracket is of no concern to me but the arrowed nut and stud (dowel) is loose and rattling about. This needs to come out but looks like the cam needs to be taken out to remove it

bmcecosse · Postby **bmcecosse** » 14 Nov 2013 20:08

Can't you simply tighten the nut?

motman · Postby **motman** » 14 Nov 2013 20:37

No, the whole thing has come adrift. It just feels like the threads have stripped. No one seems to have had this fault before

nick · Postby **nick** » 14 Nov 2013 21:11

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by motman

No, the whole thing has come adrift. It just feels like the threads have stripped. No one seems to have had this fault before
<hr height="1" noshade id="quote"></blockquote id="quote">

The dowel goes through sprocket and locates the cam to the sprocket. The two bolts with the lock then pull the sprocket tight to the cam.

If the whole dowel is lose it means the hole in the sprocket has elongated for some reason. If that is the case you should be able to pull it out in the forward direction

If you saw the threaded part off the dowel you will have no way of removing the cam without having the chain go slack since that threaded part goes through the chain guide and holds the sprocket/chain in place while the cam is taken out.

Once the chain goes slack you have to remove the chain cover and reset the chain tensioner which is no small job.

[img][IMG]http://i615.photobucket.com/albums/tt234/nickmi/TR7%201975/Yellow.jpg[/img]
nick
'79 TR7 DHC
'76 TR7 FHC

Workshop Help · Postby **Workshop Help** » 15 Nov 2013 00:10

Let me ask a simpletons question as I have yet to pull the manual off the shelf in the library.

If the engine functions normally with this locating dowel loose, can the damaged dowel be removed, the hole rethreaded in situ, and a larger dowel installed, including hogging out the bracket hole?

Oh, sure, lots of rags would be needed to mask off the metallic shavings. Isn't the dowel only there to support the chain sprocket when the camshaft is removed or the cylinder head taken off? Is the inside bore of the camshaft dowel hole 'normal' steel that can be tapped for new threads? Isn't there enough elbow room to do it without an extensive tear down or even camshaft replacement?

Questions, questions, questions.

Mildred Hargis

nick · Postby **nick** » 15 Nov 2013 14:34

The dowel extends through the sprocket. There is a hole in the end cam. When installing the cam it must be fitted onto the dowel. The fit is extremely close so that the sprocket is exactly centered and turns true. I suppose once the sprocket is bolted to the cam the dowel doesn't really do anything except to stand by if the cam is ever removed.

[img][IMG]http://i615.photobucket.com/albums/tt234/nickmi/TR7%201975/Yellow.jpg[/img]
nick
'79 TR7 DHC
'76 TR7 FHC

motman · Postby **motman** » 15 Nov 2013 15:11

The dowel wont pull out even with a lot of force with some very large grips.
As it doesn't serve a function in normal use I am toying with welding the nut to the sprocket to secure it. I know this is a bit of a bodge and will mean any future repairs will mean removing the chain but it will stop it moving around without the need for a major strip down.

Beans · Postby **Beans** » 15 Nov 2013 15:33

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by motman

... No one seems to have had this fault before ...<hr height="1" noshade id="quote"></blockquote id="quote">
Correct, as stated earlier, there are no threads [}:)]
The "nut" is (or should I say should be) pressed to the dowel.
Nick did a good repeat post [:p]

<center>

1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
[url="http://www.tr7beans.blogspot.com/"]My full Weblog[/url]</center>

nick · Postby **nick** » 15 Nov 2013 19:46

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Beans

[quote]Originally posted by motman

... No one seems to have had this fault before ...<hr height="1" noshade id="quote"></blockquote id="quote">
Correct, as stated earlier, there are no threads [}:)]
The "nut" is (or should I say should be) pressed to the dowel.
Nick did a good repeat post [:p]

<center>

1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
[url="http://www.tr7beans.blogspot.com/"]My full Weblog[/url]</center>
<hr height="1" noshade id="quote"></blockquote id="quote">

When you get old you start doing that. [:D]

[img][IMG]http://i615.photobucket.com/albums/tt234/nickmi/TR7%201975/Yellow.jpg[/img]
nick
'79 TR7 DHC
'76 TR7 FHC

Beans · Postby **Beans** » 15 Nov 2013 22:09

Don't tell me [:D]

<center>

1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
[url="http://www.tr7beans.blogspot.com/"]My full Weblog[/url]</center>

motman · Postby **motman** » 16 Nov 2013 05:40

[quote]Originally posted by Beans

[quote]Originally posted by motman

... No one seems to have had this fault before ...<hr height="1" noshade id="quote"></blockquote id="quote">
Correct, as stated earlier, there are no threads [}:)]
The "nut" is (or should I say should be) pressed to the dowel.
Nick did a good repeat post [:p]

<center>

1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
[url="http://www.tr7beans.blogspot.com/"]My full Weblog[/url]</center>
<hr height="1" noshade id="quote"></blockquote id="quote">

And your point is what exactly?

Anonymous

Camshaft sprocket locating pin?

Who is online