UNF Bolts

[Nick DV]

Not having much success today with things, and now I cannot seem to find someone that will sell me four M12 UNF x 100mm bolts without taking out a mortgage! I need them to hold an engine in an engine stand, so any help would be very much appreciated

 

[Kram]

M12 UNF? Or 1/2" UNF?
This might do it?

1/2" 9/16" 5/8" & 3/4" Zinc UNF High Tensile Grade 5, 8.8 Hex Head Bolts | eBay

UNF HEXAGON HEAD BOLTS. UNF Thread (AF). Grade 5 (8.8) High Tensile Steel. Zinc UNF NUTS. Zinc UNF NYLOC NUTS. Coating - Clear bright Zinc plated. 9/16" 4 1/2" 1 3/8" 13/16" 3/8" 18. 5/8" 2 1/2" 1 1/2" 15/16" 3/8" 18.

www.ebay.co.uk

 

[Matrixx]

Try a generator company, its the sort of bolt used on USA engines, CAT, Cummins etc.

 

[julianf]

As above, I've always got unc/f bolts off eBay in small quantities.

 

[Nick DV]

M12 UNF? Or 1/2" UNF?
This might do it?

1/2" 9/16" 5/8" & 3/4" Zinc UNF High Tensile Grade 5, 8.8 Hex Head Bolts | eBay

UNF HEXAGON HEAD BOLTS. UNF Thread (AF). Grade 5 (8.8) High Tensile Steel. Zinc UNF NUTS. Zinc UNF NYLOC NUTS. Coating - Clear bright Zinc plated. 9/16" 4 1/2" 1 3/8" 13/16" 3/8" 18. 5/8" 2 1/2" 1 1/2" 15/16" 3/8" 18.

www.ebay.co.uk

Thanks Kram. It could be 1/2" UNF, it's just that a local bolt supplier (who couldn't supply one) looked at mine and said it was M12. It's definitely a fine thread, and its to go into the block of a Lexus V8 engine.

Try a generator company, its the sort of bolt used on USA engines, CAT, Cummins etc.

Thanks Matrixx

As above, I've always got unc/f bolts off eBay in small quantities.

Thanks Julian

 

[Kram]

Do you have a bolt that fits to measure?
I find it unliky a japenese? Lexus engine would have imperial bolts so it could be M12 x1 or M12 x 1.25

 

[Nick DV]

Do you have a bolt that fits to measure?
I find it unliky a japenese? Lexus engine would have imperial bolts so it could be M12 x1 or M12 x 1.25

I have the bellhousing bolts, it's just that they are too short to go through the engine stand and into the block. I can measure these.

 

[Agroshield]

It's definitely a fine thread, and its to go into the block of a Lexus V8 engine.

If Lexus, there is 100% chance it is not UNF. As above, it will be M12 fine thread. The trouble is, there are three M12 fine pitches: 1.5, 1.25 and 1.0.

If you have any standard metric bolts kicking around, you can use them to assess the pitch. If M10 matches, the pitch is 1.5; if M8 matches, the pitch is 1.25; if M6 matches, the pitch is 1.0

 

[Melvyn Best]

A set of thread gauges is a good investment , probably a fiver ? as said it’s not going to be UNF on a Lexus

 

[Nick DV]

If Lexus, there is 100% chance it is not UNF. As above, it will be M12 fine thread. The trouble is, there are three M12 fine pitches: 1.5, 1.25 and 1.0.

If you have any standard metric bolts kicking around, you can use them to assess the pitch. If M10 matches, the pitch is 1.5; if M8 matches, the pitch is 1.25; if M6 matches, the pitch is 1.0

Thanks Argo. I'd take a bet they are M12 x 1.25 but I'll use your method of checking as soon as I get home

 

[Nick DV]

A set of thread gauges is a good investment , probably a fiver ? as said it’s not going to be UNF on a Lexus

Thanks Melvyn, sounds a great idea given that I'm messing around with all things metal these days!

 

[Gragson]

After advice on here, I looked for imperial Moore & Write set and got a great metric & imperial set for a tenner in great nick!

 

[Melvyn Best]

Thanks Melvyn, sounds a great idea given that I'm messing around with all things metal these days!

A Zeus? ( spelling) book is a good investment as well

 

[not done it yet]

Agri merchants may be the easiest to find - but not if you are in never never land.

I generally use GWR-Fasteners, on epay, if I want to order from my lounge.

 

[Nick DV]

After advice on here, I looked for imperial Moore & Write set and got a great metric & imperial set for a tenner in great nick!

Thanks Gragson, I'll have a look at some of those.

A Zeus? ( spelling) book is a good investment as well

Thanks Melvyn. I was sorting through some of the 'junk' I collected over the years and I'm pretty sure there was one of these amongst it!

 

[Nick DV]

Agri merchants may be the easiest to find - but not if you are in never never land.

I generally use GWR-Fasteners, on epay, if I want to order from my lounge.

Cheers mate, I'll probably take the lounge option

 

[winchman]

We bought ours at the Jumble from a regular trader, but he did tell me certain old thread forms are very expensive now as they are in short supply?

 

[Hood]

Probably M12 x 1.5.

If you have a standard M10 bolt (not from the Lexus) then you could lay it alongside the M12 and see if the pitch is the same.

Reason I say not an M10 from the Lexus is because it will almost certainly be a fine thread, M10 x 1.25 rather than the normal M10 x 1.5.

The Japanese tend to use metric fine on 10 and 12mm fasteners.

 

[anto44]

I have a Lexus engine on the bench here and the bellhousing bolts are m12x1.25
That's standard for Toyota/lexus although I'm sure there are some exceptions

 

[Nick DV]

We bought ours at the Jumble from a regular trader, but he did tell me certain old thread forms are very expensive now as they are in short supply?

Thanks WM, always worth bearing in mind

Probably M12 x 1.5.

If you have a standard M10 bolt (not from the Lexus) then you could lay it alongside the M12 and see if the pitch is the same.

Reason I say not an M10 from the Lexus is because it will almost certainly be a fine thread, M10 x 1.25 rather than the normal M10 x 1.5.

The Japanese tend to use metric fine on 10 and 12mm fasteners.

Thanks Hood, pretty sure it’s the M12x1.25

I have a Lexus engine on the bench here and the bellhousing bolts are m12x1.25
That's standard for Toyota/lexus although I'm sure there are some exceptions

Thanks Anto, that confirms it I’ll get some ordered now.