shuffle pins

[nicolas]

can someone give me info on how to do it and what parts are needed to put shuffle pins in a case. not sure if there are different types (cons/ benefits) but what I have seen is a hard metal machined bushing (skf sells something similar to pin moulds or parts in a specific position) around the two center studs in a case.

thanks

[PPRMicke]

can someone give me info on how to do it and what parts are needed to put shuffle pins in a case. not sure if there are different types (cons/ benefits) but what I have seen is a hard metal machined bushing (skf sells something similar to pin moulds or parts in a specific position) around the two center studs in a case.

thanks

Then I oppose the question
How much do you rev the machine, how long is the stroke on the crankshaft
  When you mount these there, you have 0 fit on one side and on the other side h7 (0.02mm) It works with semi-hard steel
The fact that you have these is to prevent the block halves from moving laterally. Many times this happens because the clamping force is not sufficient
Type that the surface finish is not good enough. It could also be that you do not have a gasket adhesive that is not stable in the then moving block halves
Today's glue type locktite 570 prevents friction between the surfaces (volvo/gm/bmw) use that type on alu/magnesum engines to avoid this problem

[nicolas]

very interesting and good remark. I have seen cases where the center saddles has marks that indicate that it isn't rigid. or it came loose at some point.

i will look into the lactate 570 option. thank you for your advice.

the concrete engine I am thinking of is a 78 stroke engine that will see 7000 rpms.

[PPRMicke]

There shouldn't be a problem with that speed and stroke without the Shuffle pin
As wrote, it is very careful if the halves have damage to the surfaces
On the 1600 challenge machine that I'm involved with
Are there no shuffle pins
 But we drive it like hell like 8400-8600 rpm and more with 2.6 bar or more (over 400hp on the wheels )
What is very important is the balance of the parts
Another thing is that you have control over the ignition so the slightest misfire can cause vibratons in the crankshaft that continue in the block
Shuffle pin is an emergency solution that began to be used when the stroke length began to exceed 80 mm in the USA
Often it was combined with a lightened flywheel and an aluminum pulley
Then the crankshaft self-oscillates due to the turning force when you release the clutch. If the crankshaft breaks, it is always in the same place between the center bearing and the 3rd crank bearing
/// M

[nicolas]

There shouldn't be a problem with that speed and stroke without the Shuffle pin
As wrote, it is very careful if the halves have damage to the surfaces
On the 1600 challenge machine that I'm involved with
Are there no shuffle pins
 But we drive it like hell like 8400-8600 rpm and more with 2.6 bar or more (over 400hp on the wheels )
What is very important is the balance of the parts
Another thing is that you have control over the ignition so the slightest misfire can cause vibratons in the crankshaft that continue in the block
Shuffle pin is an emergency solution that began to be used when the stroke length began to exceed 80 mm in the USA
Often it was combined with a lightened flywheel and an aluminum pulley
Then the crankshaft self-oscillates due to the turning force when you release the clutch. If the crankshaft breaks, it is always in the same place between the center bearing and the 3rd crank bearing
/// M

thank you for your insight again. I will look at it this way. very helpful

as for the crank. I had an engine here where the crank broke between the flywheel saddle and number 3... but I suspect clutch issues. and yes vibrations. clutch more then likely, but misfires tend to do a bot of damage I am learning... thank you.