Would folks agree with me, if when fitting new pistons &you find the circlips are a loose fit in the pistons, thatyou should reject either the circlips or the pistons or both? By loose fit, I mean no pressure exerted on thecirclip groove when released from the tool. Seagar type clips, only one clip really bad, two easily rotated, one an almost tight fit.
Yes something is wrong. SE…
Yes something is wrong. SEEGER circlips should be a tight fit (and wire type too)
They should only be able to turn if you pull one eye towards the other eye to rotate them.... pulling one eye away away from the other should lock the clip pretty well solid in its groove. The correct fitting Seeger clip should have 1/8" clearance between its eyes when fitted. (Tuning for Speed)
It could be that the piston was designed for wire type circlips. Seeger clips require a flat bottomed groove whereas wire clips use a round bottom groove:
To check is difficult but with a magnifying glass you might be able to see. Otherwise, feel the profile with a needle or even press in some "Plasticine" or "BlueTack" to see what shape you have. Once you know what type of clip the piston is designed for you just need the correct type and size, diameter wise and one that is also the correct width (same as the groove)....The piston should be OK
Les
Curse thegoon who taught m…
Curse thegoon who taught me SEAGAR.
Great advice thanks. I'll be looking to confirm tomorrow, but I think they looked round bottomed.Should have noticed that, but didn't.
Hi John....don't know wha…
Hi John....don't know what pistons you have but these might be correct if you have round bottomed grooves...
http://www.rgmnorton.co.uk/buy/piston-circlip-round-wire-type-twins-with-gpm-pistons-4_217.htm
Les
Blu-tack test shows flat b…
Blu-tack test shows flat bottomed & straight sided grooves, so I imagine seeger type circlips are correct. However I can actually move the circlips from side to sidein one piston, ne'er mind rotate.
These are the £83+vat Hepolite type pistons. I already had an issue with the 3 piece oil rings being extremely tight in the bores (I could not get them to enter the bores even using ring clamps) & they were exchanged by the vendor with GPM type on Saturday.
Wishing I'd bought the expensive type from Andover Norton now. Might still have to go that way.
Hi John...OK then maybe ta…
Hi John...OK then maybe take a look at these two different types and select the size that would suit.
Note that RGM calls them "SEGAR" type so another spelling variation.... but equally wrong.
http://www.rgmnorton.co.uk/buy/piston-circlip-920-old-type-set-of-4_215.htm
Les
Most kind of you Les, to p…
Most kind of you Les, to provide such good info. I came across the old pistons this afternoon & the circlips were slightly bigger, so I fitted them & they felt much better. At least I can get on with reassembly now without waiting for more clips, which may or may not fit in 3 days time.
I must be a magnet for duff & wrong gear; The rocker shims & Thackray washers kit, found the washers measured 36 thou thick instead ofthe 16 thou they shouldbe.
Normal advice is to never…
Normal advice is to never reuse circlips, when you see the damage a loose circlip causes and the pin gets free movement you can understand why, you may be lucky and get to the next rebore size before it cleans up or maybe not. Measure the old good fitting ones and compare them to the RGM OD dimension, if its the same or the RGM is slightly bigger then buy the RGM ones and bin the old ones, send the others back as not fit for purpose.
I would normally follow su…
I would normally follow such good advice, but on this occasion I'm going to stick with the "old" circlips which fit & grip very well. They were not too "old" either, as this was a rebuilt engine with very few miles but was water contaminated. I shall not be recommending Hepolite cheapo type pistons to others. I should have read the warning signs, packaged in bubblewrap instead of proper boxed gear, slip fit pin, the oil rings were too tight & replaced with GPM type, now the circlips too small. I shall inform the vendor of the circlip problem, but not worth the stamp sending them back. Lesson learned, GPM would have been best.
If circlips have been in a…
If circlips have been in and out then they're 'used'.
I'd be too paranoid to put them in again.
Definately reject the circlips and possibly the pistons but I would ask for dimensions to check first.