Removing press fit pistons without damaging pistons
Turbo Mini Forums

gonna try and remove the slipper pistons off my 998's rods tomorrow, anyone have any advice?

I have a feeling im gonna ruin the pistons, but not sure what other choice ive got?

will i ruin the pistons getting the little end hot enough with the oxy?

cheers

joe

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

The way I did it with the 1275 interference fit pins (without having access to a press :( ) was by making up a puller.

A block of hardwood, as thick as the gudgeon pin is long, and carefully shaped to the profile of the side of the piston - just by using and angle grinder with a coarse sanding disk, then finished with a flapper wheel.

Drill a hole through it slightly larger than the pin.

Bit of M10 studding, two nuts locked together on one end, studding fed through the pin, through the hardwood block, steel plate drilled M10 (to spread the load over the hardwood) a pack of well oiled washers to act as a bearing and a "thick" M10 nut to wind down on. Make sure the hole in the hardwood is centralised for where the pin will enter it.

I only needed the heat from a standard propane/butane plumbers blowtorch on the top of the rod to free the pin enough to pull it through with the studding.

I can't remember if the 998 pins are slightly smaller though - might not get M10 studding to go through the pin or the nuts to go through the piston ???

Edited by Rod S on 7th Dec, 2008.

Schrödinger's cat - so which one am I ???

Hi
I had mine done (1275 rods) at a local place. The guy heated the end of rod with the oxy to a straw colour then the pins near enough fell out.
Cheers
Gavin :)

VEMs Authorised Installer / Re-seller. K head kits now available!

WB/EGT gauges. Click here for customers write-up

Visit www.doyouneedabrain.co.uk

My Mini build diary

if the pistons are slipper style somthing like this will work.

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=122262

rod, on the 998 the slipper pistons have a nice flat ring aroud the pin

mini13. brilliant, last night i was searching for 'grudgeon' and couldnt find anything, thought the search was buggered again, but turns out its me!

cheers guys

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

lol,

1275 pins are approx .810" I imagine small bore ones are the same

Schrödinger's cat - so which one am I ???

Not tried taking press ftr pistons off yet,but just about to for an A+ engine I am starting to build. I always felt thet heating the little end was a bit dodgy and had visions of the rod snapping later and totalling the engine, so I will go the puller route.Once you have made the bits you will always have them.I have a box full of home made special tools, most of which I have only used once !

Hi,
Mine are still going strong in the 1380, 10 years later. :)
Cheers,
Gavin :)

VEMs Authorised Installer / Re-seller. K head kits now available!

WB/EGT gauges. Click here for customers write-up

Visit www.doyouneedabrain.co.uk

My Mini build diary

There are no issues with heating the rod up to get the interference fit pins in and out, just allow them to air cool afterwards.