Cylinder Head Washers, Anything special about them? Options

[bbrock]

The washers I took off my heads (Type 4) 30 years ago got mixed in with my other hardware. I fished out 16 M10 washers that fit, but want to make sure I'm installing correct washers and maybe source some new ones if needed. PET just lists:

washer
A 10,5

Are they special thickness or hardness etc.?

BTW, anyone know what the "A", "B", etc. for hardware specs in the PET mean? I haven't been able to find a key. Must be looking in the wrong place.

[Valy]

Yes, they are harder than regular washers.
You need to use the correct ones or they will smash and bad things can happen.

[bbrock]

Yes, they are harder than regular washers.
You need to use the correct ones or they will smash and bad things can happen.

Thank you! Exactly what I would have guessed. Would these from Belmetric work? https://www.belmetric.com/hardened-metric-f...in-p-10688.html

[Mblizzard]

Yes, they are harder than regular washers.
You need to use the correct ones or they will smash and bad things can happen.

Thank you! Exactly what I would have guessed. Would these from Belmetric work? https://www.belmetric.com/hardened-metric-f...in-p-10688.html

If you can't find let me know I have a new set I can send you for free.

[bbrock]

Yes, they are harder than regular washers.
You need to use the correct ones or they will smash and bad things can happen.

Thank you! Exactly what I would have guessed. Would these from Belmetric work? https://www.belmetric.com/hardened-metric-f...in-p-10688.html

If you can't find let me know I have a new set I can send you for free.

Thanks for the generous offer! I'll take you up on it. I just measured one of the washers I have which I'm pretty sure was an actual head washer. It is both thicker and larger O.D. than the Belmetric ones. Given the critical nature of this part, I'd rather not make guesses.

I'll PM you.

[jcd914]

What are the dimensions of the stock washers?

I wonder if a non-hardened thicker washer would make up the the lack of hardening?

At the low torque these are under the washer is not going to crush, even if it is not hardened.
A non hardened washer would not distribute the load out to the edges the same as a hardened washer would but an extra thick washer might.

Jim

[bbrock]

What are the dimensions of the stock washers?

I wonder if a non-hardened thicker washer would make up the the lack of hardening?

At the low torque these are under the washer is not going to crush, even if it is not hardened.
A non hardened washer would not distribute the load out to the edges the same as a hardened washer would but an extra thick washer might.

Jim

The one I measured which I'm 90% sure was one of the original head washers had the following dimensions in mm:

I.D. - 10.5
O.D. - 21.75
Thickness - 3

Assuming it's a head washer, it's already pretty thick. In addition to the torque, I wonder about the pounding these things get. Seems like the nuts might pound down through softer material and resulting in loss of torque.

Which brings up another question: locktite on the studs or no?

[Mblizzard]

What are the dimensions of the stock washers?

I wonder if a non-hardened thicker washer would make up the the lack of hardening?

At the low torque these are under the washer is not going to crush, even if it is not hardened.
A non hardened washer would not distribute the load out to the edges the same as a hardened washer would but an extra thick washer might.

Jim

The one I measured which I'm 90% sure was one of the original head washers had the following dimensions in mm:

I.D. - 10.5
O.D. - 21.75
Thickness - 3

Assuming it's a head washer, it's already pretty thick. In addition to the torque, I wonder about the pounding these things get. Seems like the nuts might pound down through softer material and resulting in loss of torque.

Which brings up another question: locktite on the studs or no?

I could be wrong on this but the concept behind the harden washers is to prevent crushing and to resist deformation during the heat cycles. The engineers have worked this out and it would seem difficult to reverse engineer a different washer with different properties to do the do the same job.

No locktight.