Alternator belt tensioning and exhaust bracket

[Chris71]

Sorry, couple of numptie questions, but thought it wise to check...

My alternator belt has started squealing badly again and there's no obvious means of tensioning it as it stands. There are only the three main bolts:



Looking at the Caterham website I gather there's usually an adjustor bolt on the right hand side of this shot, but it's not present on mine. I presume it's just a missing bolt rather than a different type of adjustor or anything?

Presumably once I've sourced a bolt all I need to do is losen the top mounting bolt and the bottom right mounting bolt, set the belt tension (just 'twangable'?) and then do the other two up again?

There's no obvious sign of damage to the belt, but it has been slipping quite a bit on start up (on and off) for a while - should I replace it do you reckon?

Secondly, the rear mounting point for my exhaust has what looks like a DIY bracket:



I take it'll be a straight swap for the normal S3 Rover bracket (https://www.caterhamparts.co.uk/product_info.php?products_id=3164&osCsid=73faa81852190a57c096b8593ccf668d) - i.e. there's not a special Roadsport A exhaust or anything like that?

Can anyone remember how the bracket is attached to the chassis - is there a captive bolt or something or am I going to have to remove the inner skin of the door to get to it?

[johnvthe2nd]

am I missing something? it looks like the bottom rhs nut is the adjustment? (you'll have to undo the other two a little as well)

[Chris71]

johnvthe2nd said:

am I missing something? it looks like the bottom rhs nut is the adjustment? (you'll have to undo the other two a little as well)

I think I might have been missing something. For some reason I had a notion there was a fourth bolt that screwed into the end of the bracket at ninety degrees and tensioned pushed the alternator out to tension it. Think I've got the wrong end of the stick...

So it's just a case of losening everything, levering it out manually (crow bar or something) and then re-tightening?

Edited by Chris71 on Tuesday 31st August 13:59

[johnvthe2nd]

yes!

[ewenm]

Chris71 said:

johnvthe2nd said:

am I missing something? it looks like the bottom rhs nut is the adjustment? (you'll have to undo the other two a little as well)

I think I might have been missing something. For some reason I had a notion there was a fourth bolt that screwed into the end of the bracket at ninety degrees and tensioned pushed the alternator out to tension it. Think I've got the wrong end of the stick...

So it's just a case of losening everything, levering it out manually (crow bar or something) and then re-tightening?

My alternator does have one of those small tensioning bolts you describe, but it isn't vital, merely helpful.

Edit: I think it's a captive nut for the exhaust bracket and I don't know of anything special about them, I think they are all standard.

Edited by ewenm on Tuesday 31st August 15:14

[Chris71]

ewenm said:

My alternator does have one of those small tensioning bolts you describe, but it isn't vital, merely helpful.

Ah! So I wasn't going mad...

[ewenm]

Chris71 said:

ewenm said:

My alternator does have one of those small tensioning bolts you describe, but it isn't vital, merely helpful.

Ah! So I wasn't going mad...

Not in that specific instance, no.

[Chris71]

ewenm said:

Chris71 said:

ewenm said:

My alternator does have one of those small tensioning bolts you describe, but it isn't vital, merely helpful.

Ah! So I wasn't going mad...

Not in that specific instance, no.

The voices told me otherwise, I knew I was wrong to distrust them.

[BertBert]

Something looks a bit odd about the exhaust mounting Chris. This is all from memory, but I think the bobbin is usually in compression. So in order from the top down, you'd have exhaust bracket, bobbin, body-bracket.

Yours has from the top down, body-bracket, bobbin, exhaust bracket.

That has the effect of raising the silencer up by an amount equivalent to the bobbin plus the two brackets.

Bert

[Incorrigible]

Much as it pain me to say it. Bert is spot on :;

[V7SLR]

BertBert said:

Something looks a bit odd about the exhaust mounting Chris. This is all from memory, but I think the bobbin is usually in compression. So in order from the top down, you'd have exhaust bracket, bobbin, body-bracket.

Yours has from the top down, body-bracket, bobbin, exhaust bracket.

That has the effect of raising the silencer up by an amount equivalent to the bobbin plus the two brackets.

Bert

No, he's wrong. It'll raise it by an amount equivalent to the bracket plus 2 bobbins

Putting it in compression as Bert says, is less likely to lead to failure. However it's not always possible due to varying primary/silencer types leading to differing positions when you get to the bobbin end.

Stu.

[Chris71]

BertBert said:

Something looks a bit odd about the exhaust mounting Chris. This is all from memory, but I think the bobbin is usually in compression. So in order from the top down, you'd have exhaust bracket, bobbin, body-bracket.

Yours has from the top down, body-bracket, bobbin, exhaust bracket.

That has the effect of raising the silencer up by an amount equivalent to the bobbin plus the two brackets.

Bert

Because it's got a homemade right-angle bracket on there, rather than the usual swept-forward design it'd foul the mud guard if mounted on top. It was mounted underneath as a bodge I think (before my time). I just haven't got round to fixing it yet. I wanted to check the S3/Rover exhaust brackets are all to the same pattern before I ordered one!

[BertBert]

V7SLR said:

No, he's wrong. It'll raise it by an amount equivalent to the bracket plus 2 bobbins

Well there's a first for everything!

Chris, I have just looked and have a *brand new* swept forward bracket if it's of any use to you. Let me know and I'll put it in the post.

Bert

[Chris71]

Too late Bert! I ordered various bits including the bracket from Caterham over lunch.

The offer is much appreciated though, I still owe you one for the starter motor lead.

[Chris71]

Doh! Even with the proper bracket that sits further forward the exhaust still fouls the rear mudguard. I had images of burning fiberglass the next time the exhaust got hot so I've put everything back to the way it was and, for now, I'll just have to wince every time I go over a bump! I don't know if the exhaust is bent or if it's just the wrong type. In 18 months time it'll be due for an MOT-friendly (catalyst) exhaust anyway, so might treat it to one ahead of schedule.

ETA: Oh dear, this morning's just got a whole lot worse. Had a look at the alternator and while I could just about release the bottom of the two bolts (the one that mounts onto the bracket) the top one was massively over-tightened. When I finally got movement it came from the nut rounding off rather than any actual turning on the thread. Not really sure what to do now. I might be able to get a more even purchase on it with a socket (on a solid T-bar) or a ring spanner I guess?

[ewenm]

Soak it in penetrating oil overnight, find a tight-fitting socket and a long bar. The long bar will also be useful for tensioning it later braced between the engine and alternator.

My exhaust is very close to (but doesn't foul) the rear arch and I've had no fibreglass melting/burning issues.

[Chris71]

ewenm said:

Soak it in penetrating oil overnight, find a tight-fitting socket and a long bar. The long bar will also be useful for tensioning it later braced between the engine and alternator.

Yep, that's basically the plan. I might have to tidy it up with a file first, it's made a bit of mess of the nut.

ewenm said:

My exhaust is very close to (but doesn't foul) the rear arch and I've had no fibreglass melting/burning issues.

Here the tip fo the tail pipe would actually be touching. That's not a good idea surely? I only say that after catching my hand on 'said piece of pipe shortly after turning the engine off in the past...