Omega Owners Forum

Chat Area => General Car Chat => Topic started by: Viral_Jim on 27 May 2019, 16:18:59

Title: Oh how I love garages
Post by: Viral_Jim on 27 May 2019, 16:18:59
 Oh how I love garages  ::)

Pulled the crankshaft pulley bolt only to discover that the previous belt change had been completed courtesy of some barely trained chimp...

(https://i.ibb.co/kySN4qD/IMG-20190527-160639.jpg) (https://ibb.co/H2H5tGP)

So the T'can will have to wait until next weekend when I can get a replacement pulley bolt. I just hope I don't have to drill and tap the crank and go up a size. What do you chaps think, hoping in vain?

(https://i.ibb.co/VTSQ0zS/IMG-20190527-161705-01.jpg) (https://ibb.co/cQFCKZF)
Title: Re: Oh how I love garages
Post by: ronnyd on 27 May 2019, 16:29:52
You might be able to clear that thread out if you can source a tap. Do you a friendly m/c shop?
Title: Re: Oh how I love garages
Post by: biggriffin on 27 May 2019, 16:34:58
 Go to local fastner supply's take bolt, ask do you have one of these, guessing it's a m,14*1.25
Title: Re: Oh how I love garages
Post by: Viral_Jim on 27 May 2019, 17:43:54
Go to local fastner supply's take bolt, ask do you have one of these, guessing it's a m,14*1.25

Good idea, ive found a good-looking local place. Cheers :y

You might be able to clear that thread out if you can source a tap. Do you a friendly m/c shop?

Sadly not, not round here at least (not had chance to make a nuisance of myself yet!). Once I've got the bolt spec, I'll probably just order one from Amazon, given it will probably be a single-use item in my lifetime.  ;D

My main issue is I'm not sure how to determine thread pitch (will Google later) so I'll just goto the fastener place and ask them what they've sold me  ;D. Everything I've tapped before has been M5 / M6 size and threads are either "coarse" or "fine". But I suspect it's a bit more technical than that   ;D
Title: Re: Oh how I love garages
Post by: Nick W on 27 May 2019, 17:52:16
Go to local fastner supply's take bolt, ask do you have one of these, guessing it's a m,14*1.25

Good idea, ive found a good-looking local place. Cheers :y

You might be able to clear that thread out if you can source a tap. Do you a friendly m/c shop?

Sadly not, not round here at least (not had chance to make a nuisance of myself yet!). Once I've got the bolt spec, I'll probably just order one from Amazon, given it will probably be a single-use item in my lifetime.  ;D

My main issue is I'm not sure how to determine thread pitch (will Google later) so I'll just goto the fastener place and ask them what they've sold me  ;D . Everything I've tapped before has been M5 / M6 size and threads are either "coarse" or "fine". But I suspect it's a bit more technical than that   ;D




The easiest way is to use a thread pitch gauge, but if you had one you'd have done that already. It's worth buying one for other jobs, as they're cheap. Mine was about £5.


Next is to measure the distance between each thread crest using a caliper -  a cheap digital one will be plenty good enough and you might already have one. You'll be looking at a measurement of 1.25, 1.5 or maybe 1.75 mm.


If you have a decent steel rule you could use that, but it does require a good eye.


While you have the measuring kit out, check the diameter of the thread as well. This will enable you to acquire a correctly sized bolt.



Title: Re: Oh how I love garages
Post by: ronnyd on 27 May 2019, 18:27:25
Go to local fastner supply's take bolt, ask do you have one of these, guessing it's a m,14*1.25

Good idea, ive found a good-looking local place. Cheers :y

You might be able to clear that thread out if you can source a tap. Do you a friendly m/c shop?

Sadly not, not round here at least (not had chance to make a nuisance of myself yet!). Once I've got the bolt spec, I'll probably just order one from Amazon, given it will probably be a single-use item in my lifetime.  ;D

My main issue is I'm not sure how to determine thread pitch (will Google later) so I'll just goto the fastener place and ask them what they've sold me  ;D . Everything I've tapped before has been M5 / M6 size and threads are either "coarse" or "fine". But I suspect it's a bit more technical than that   ;D




The easiest way is to use a thread pitch gauge, but if you had one you'd have done that already. It's worth buying one for other jobs, as they're cheap. Mine was about £5.


Next is to measure the distance between each thread crest using a caliper -  a cheap digital one will be plenty good enough and you might already have one. You'll be looking at a measurement of 1.25, 1.5 or maybe 1.75 mm.


If you have a decent steel rule you could use that, but it does require a good eye.


While you have the measuring kit out, check the diameter of the thread as well. This will enable you to acquire a correctly sized bolt.




Exactly wot he said. :y
Title: Re: Oh how I love garages
Post by: Viral_Jim on 27 May 2019, 22:46:23

The easiest way is to use a thread pitch gauge, but if you had one you'd have done that already. It's worth buying one for other jobs, as they're cheap. Mine was about £5.


Next is to measure the distance between each thread crest using a caliper -  a cheap digital one will be plenty good enough and you might already have one. You'll be looking at a measurement of 1.25, 1.5 or maybe 1.75 mm.


If you have a decent steel rule you could use that, but it does require a good eye.


While you have the measuring kit out, check the diameter of the thread as well. This will enable you to acquire a correctly sized bolt.

Thanks for that explanation Nick, clear enough that even I can understand it ;). I've ordered thread pitch gauge and calipers as I own neither.  :-[

 Pretty confident as to which end of a spammer you hang on to, but when it comes to any kind of engineering knowledge, I'm done  ;D
Title: Re: Oh how I love garages
Post by: Nick W on 27 May 2019, 22:59:51
I didn't mention this because your problem bolt is metric, but you don't measure imperial pitches that way. Metric threads are defined by the distance between adjacent features, so you measure them directly. Imperial is defined as Threads Per Inch(TPI), so the reliable way to check without a gauge is to measure an inch and count the number of threads it spans.
Title: Re: Oh how I love garages
Post by: New POD on 28 May 2019, 22:13:25
You might investigate Thread inserts (Helicoils), which the aerospace world would fit as a matter of course.
Title: Re: Oh how I love garages
Post by: Viral_Jim on 28 May 2019, 22:53:58
You might investigate Thread inserts (Helicoils), which the aerospace world would fit as a matter of course.

I've heard of them, not sure how they work, will do some further research.

In any event, if I can't re-cut/clean the 18mm thread with a tap (coming tomorrow) I'll probably get a mobile mechanic to come and rectify. Mostly because I can't get a drill between the block and the AC radiator (not to mention the lack of an 18.5mm drill bit and an M20 tap).

So far I'm down £2.50 on a substitute pulley bolt, £20 on an M18 tap and tap wrench. I'd rather not snap a drill bit or a tap off in the crank. Call it quitting while I'm ahead.  ;D
Title: Re: Oh how I love garages
Post by: Andy B on 28 May 2019, 23:29:50
You might investigate Thread inserts (Helicoils), which the aerospace world would fit as a matter of course.

I've heard of them, not sure how they work, will do some further research.

In any event, if I can't re-cut/clean the 18mm thread with a tap (coming tomorrow) I'll probably get a mobile mechanic to come and rectify. Mostly because I can't get a drill between the block and the AC radiator (not to mention the lack of an 18.5mm drill bit and an M20 tap).

So far I'm down £2.50 on a substitute pulley bolt, £20 on an M18 tap and tap wrench. I'd rather not snap a drill bit or a tap off in the crank. Call it quitting while I'm ahead.  ;D

You don't need to go the full Helicoil route on a thread that's been damaged as little as this. Just clean it up with a tap & that will be enough. Just be careful with the tap ... you REALLY don't want to snap a hardened tap in the crank ... it'd be a tw4t & a half to remove.
Title: Re: Oh how I love garages
Post by: Sir Tigger KC on 28 May 2019, 23:44:23
Whack it back in with a smear of liquid metal. That'll be alright!  :y
Title: Re: Oh how I love garages
Post by: aaronjb on 29 May 2019, 08:40:30
You don't need to go the full Helicoil route on a thread that's been damaged as little as this. Just clean it up with a tap & that will be enough. Just be careful with the tap ... you REALLY don't want to snap a hardened tap in the crank ... it'd be a tw4t & a half to remove.

Was about to say the same - snap a tap and you'll be spending several hours with a hammer and a punch trying to either drift it our or shatter it into pieces - or taking the crank out to have it spark eroded out of the hole..

But with that little damage (tbh the thread in the hole doesn't even look chewed in that picture) the tap should go in easily :y if it starts to bind, back it out a quarter turn to break any chips and then go in a bit further, rinse, repeat.
Title: Re: Oh how I love garages
Post by: henryd on 29 May 2019, 08:47:34
You might investigate Thread inserts (Helicoils), which the aerospace world would fit as a matter of course.

I've heard of them, not sure how they work, will do some further research.

In any event, if I can't re-cut/clean the 18mm thread with a tap (coming tomorrow) I'll probably get a mobile mechanic to come and rectify. Mostly because I can't get a drill between the block and the AC radiator (not to mention the lack of an 18.5mm drill bit and an M20 tap).

So far I'm down £2.50 on a substitute pulley bolt, £20 on an M18 tap and tap wrench. I'd rather not snap a drill bit or a tap off in the crank. Call it quitting while I'm ahead.  ;D

You don't need to go the full Helicoil route on a thread that's been damaged as little as this. Just clean it up with a tap & that will be enough. Just be careful with the tap ... you REALLY don't want to snap a hardened tap in the crank ... it'd be a tw4t & a half to remove.

Yes definitely care needed as the case hardening of the crank will be very difficult to tap although as already  said the hole threads look pretty good
Title: Re: Oh how I love garages
Post by: Viral_Jim on 29 May 2019, 10:17:46
Thanks chaps.

Duly noted re. busting the tap, as always I shall go gently and apply some suitable lubricant.  :y

However the job will have to wait until Sunday when I have some time to look at it properly.
Title: Re: Oh how I love garages
Post by: biggriffin on 29 May 2019, 10:28:01
Whack it back in with a smear of liquid metal. That'll be alright!  :y


Well said sir,  when's that bolt ever going to be removed again. If not whack it back in, ..

Another quality repair by fixit bodgey inc.
Title: Re: Oh how I love garages
Post by: Sir Tigger KC on 29 May 2019, 12:39:29
Whack it back in with a smear of liquid metal. That'll be alright!  :y


Well said sir,  when's that bolt ever going to be removed again. If not whack it back in, ..

Another quality repair by fixit bodgey inc.

Zactly!  ;D
Title: Re: Oh how I love garages
Post by: Field Marshal Dr. Opti on 11 June 2019, 16:17:33
Thanks chaps.

Duly noted re. busting the tap, as always I shall go gently and apply some suitable lubricant.  :y

However the job will have to wait until Sunday when I have some time to look at it properly.

I bet you say that to all the girls. :)
Title: Re: Oh how I love garages
Post by: ronnyd on 12 June 2019, 18:22:19
Thanks chaps.

Duly noted re. busting the tap, as always I shall go gently and apply some suitable lubricant.  :y

However the job will have to wait until Sunday when I have some time to look at it properly.

I bet you say that to all the girls. :)
Who are you, Meatloaf?
Title: Re: Oh how I love garages
Post by: Field Marshal Dr. Opti on 12 June 2019, 20:46:10
Thanks chaps.

Duly noted re. busting the tap, as always I shall go gently and apply some suitable lubricant.  :y

However the job will have to wait until Sunday when I have some time to look at it properly.

I bet you say that to all the girls. :)
Who are you, Meatloaf?

You took the words right out of my mouth. :)
Title: Re: Oh how I love garages
Post by: Andy B on 12 June 2019, 21:05:49
Thanks chaps.

Duly noted re. busting the tap, as always I shall go gently and apply some suitable lubricant.  :y

However the job will have to wait until Sunday when I have some time to look at it properly.

I bet you say that to all the girls. :)
Who are you, Meatloaf?

You took the words right out of my mouth. :)

 ;D ;D
Title: Re: Oh how I love garages
Post by: Nick W on 12 June 2019, 23:05:10
Thanks chaps.

Duly noted re. busting the tap, as always I shall go gently and apply some suitable lubricant.  :y

However the job will have to wait until Sunday when I have some time to look at it properly.

I bet you say that to all the girls. :)
Who are you, Meatloaf?

You took the words right out of my mouth. :)


I won't do that.
Title: Re: Oh how I love garages
Post by: TheBoy on 13 June 2019, 10:36:12
You took the words right out of my mouth. :)
Thats not the version my dad taught me ;D
Title: Re: Oh how I love garages
Post by: ronnyd on 13 June 2019, 12:28:07
You took the words right out of my mouth. :)
Thats not the version my dad taught me ;D
:o :o :o :o :o :o ;D
Title: Re: Oh how I love garages
Post by: Viral_Jim on 16 June 2019, 13:58:42
At the risk of steering this thread dangerously back on topic, I finally tapped the threads successfully today (two weeks off any kind of physical activity due to a cracked rib has slowed proceedings). Thanks to everyone for their advice on taps, thread pitch and the like. It is much appreciated  :y

At some point, when we get a few straight hours of it not belting it down, I'll get the thing put back together and waved off via eBay.

The Berlingo Multispace arrives tomorrow and I can barely contain my excitement.  :P
Title: Re: Oh how I love garages
Post by: STEMO on 16 June 2019, 15:02:06

The Berlingo Multispace arrives tomorrow and I can barely contain my excrement.   :o
I'm sure it won't be that bad, Jimmy.  ;D
Title: Re: Oh how I love garages
Post by: Viral_Jim on 16 June 2019, 15:25:29

The Berlingo Multispace arrives tomorrow and I can barely contain my excrement.   :o
I'm sure it won't be that bad, Jimmy.  ;D

In all seriousness Ste, we are most grateful to have it and once it's been fitted with some roof bars and a tow hitch, it will be exactly the tool for the job of getting the house renovation moving. It's only 90bhp but, being a modern diesel, it's pretty torquey, so pulling a trailer should be no issue.  :y

It just needs a couple of blasts up the motorway to clear it's tubes I reckon. 2-3000 miles per year (99% short hops) probably won't have done the dpf the world of good.
Title: Re: Oh how I love garages
Post by: STEMO on 16 June 2019, 15:43:00

The Berlingo Multispace arrives tomorrow and I can barely contain my excrement.   :o
I'm sure it won't be that bad, Jimmy.  ;D

In all seriousness Ste, we are most grateful to have it and once it's been fitted with some roof bars and a tow hitch, it will be exactly the tool for the job of getting the house renovation moving. It's only 90bhp but, being a modern diesel, it's pretty torquey, so pulling a trailer should be no issue.  :y

It just needs a couple of blasts up the motorway to clear it's tubes I reckon. 2-3000 miles per year (99% short hops) probably won't have done the dpf the world of good.
Ermmm.....helloooo....wasn't this exactly what I was saying when you said you wanted to keep it a few hours and then sell it?
Title: Re: Oh how I love garages
Post by: Viral_Jim on 17 June 2019, 00:01:39
We aren't all as astute as you my good man.