Printable View
Thanks mate.
There were two tools on my fathers workbench that used to impress me:
his valve spring compressor and
his piston ring compressor
I have a valve spring compressor but I haven't seen a piston ring compressor in the auto stores for donkeys years
Anyone know where they can be found?
one of the metal band type filter wrenches combined with a suitably shaped piece of flat tin plate from a food can works nicely.
never used one, Ive mainly just poked the piston in then worked it in with the back of a thumbnial while maintaining a slight downwards pressure on the crown.
super cheap has a small one and they can be had from pro tool places. I know my local tool place has them
The best tool for ring compressing is a wrinkle band ring compressor. Have a look at these links and scroll down to the wrinkle band ring compressor.
Piston & Bore : Motorsport-Tools.com (UK), Motorsport Tools and Equipment for Race, Rally and Car Restorers
Piston Ring Compressor-Piston Ring Compressor Manufacturers, Suppliers and Exporters on alibaba.com
I bought one a few years ago from my local car parts shop. They are a vast improvement over the ratchet style ring compressor.
Aaron.
I use the ratchet type as shown on Aaron's link - heaps of engine oil on the compressor and piston and they always slide in with gentle tapping from a hammer handle.
I bought mine from REPCO about 30 years ago but I bet they still have them,
Cheers Charlie
Awesome, guys - thank you all
I have done the thumbnail thing - once. Back in the day when I had nails...Quote:
Originally Posted by Blknight.aus
Thanks - they certainly look interesting.Quote:
Originally Posted by Aaron IIA
My father used that method - especially the gently tapping with the wooden handle of a hammer.Quote:
Originally Posted by chazza
Their claim that friction is cut in half is erroneous. Friction is independent of surface area.Quote:
Originally Posted by Aaron IIA
Whenever I have used the ratchet style ring compressor, I have found them to be either one click too tight, or one click not tight enough. When not tight enough, the rings are not fully compressed, and when too tight, a soft face hammer is needed to push the piston into the bore. The ratchet ring compressor also has a tendency to slip down the bore with the piston. The wrinkle band ring comrpessor has a screw thread for fine adjustment, so is infinetely variable. The correct amount of pressure on the rings means that the piston can usually be pressed down using both thumbs. The wrinkled nature also prevents it from sliding down into the bore. The over centre lever means it is quick to operate. Having used both styles, I would only ever use a wrinkle band ring compressor again.
Aaron,
I haven't used a wrinkle style compressor, so I have no comment on it, other than to accept your recommendation that they are good bit of kit.Quote:
Originally Posted by Aaron IIA
I don't understand your quote above; however. How can the compressor slip down the bore? It is stopped from doing that by the fact that it rests on the face of the block. ;)
Using a heavy hammer handle such as a club hammer, or a copper mallet in my experience means an easy installation. The only time I have experienced a hesitancy for the rings to enter the bore was on my S1 block, because they were installed from the bottom of the cylinder and therefore a lead had not been machined in the bore to assist assembly,
Cheers Charlie
Well, I'm up for a rebore. What I thought was a carbon lip at the top of the bores was, in fact, metal. The bore is worn.
Seeking oversized pistons and rings as we 'speak'.
Question - no-one seems to have .010" pistons - is it OK to go straight to .020"?
I know it limits the future by one step but is there any problem with it for the bore engineers?
Also - I am assuming I need to get the pistons first, right? Just so the engineers know what size to accurately bore to.
Comments welcome.
no reason you cant goto .020 straight up, the pistons were once availalble in .040 oversize as well. Once you hit that if you wanted to rebore the engine again you went to something like .080 oversize and then installed a new liner, there was a thread up on here somewhere asking what liner "X" was and it was from memroy a NOS tophat liner for a 2.25.
Usually I get the block machined first but advise the swarfy of the various size pistons that are available and usually they will try to hit the smallest oversize that they can, the bores can wear in an oval (have a look at the thrust faces on the piston skirt and you'll see what I mean) which may mean that even though the lip only needs .010 of machining to remove it getting the bore back to round may require .015 of machining which means you need to machine to the .020 piston sizes anyway.