piston rings
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Re: piston rings
A C Dodd had a You tube video of it -quite scary....and if it goes wrong.... I've never done it - although I have pressed out old pins. Needs great care to avoid damaging the piston -or bending the rod!
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philthehill
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Re: piston rings
les
So long as you do not get the flame near the piston you will be alright.
Heat the rod on its own and assemble the piston and gudgen pin to the rod at the last moment so there should be no need to get the flame anywhere near the piston
Getting the gudgen pin out is a different matter but if care is taken there should be no problem
You will NEVER bend the rod if you get it just to the blue stage.
You will if you get it to the cherry red stage.
Steve Harris (ex Downton) Racing at Combe Bisset near Salisbury (now closed down see:- http://charterhouse-cars.blogspot.co.uk/2014/04/) did a conversion that had a bushed small end so that gets rid of all the problems with the pressing in of the gudgen pin. I might consider having my rods done when next out if I can find an alternative modifier.
Best of luck
Phil
So long as you do not get the flame near the piston you will be alright.
Heat the rod on its own and assemble the piston and gudgen pin to the rod at the last moment so there should be no need to get the flame anywhere near the piston
Getting the gudgen pin out is a different matter but if care is taken there should be no problem
You will NEVER bend the rod if you get it just to the blue stage.
You will if you get it to the cherry red stage.
Steve Harris (ex Downton) Racing at Combe Bisset near Salisbury (now closed down see:- http://charterhouse-cars.blogspot.co.uk/2014/04/) did a conversion that had a bushed small end so that gets rid of all the problems with the pressing in of the gudgen pin. I might consider having my rods done when next out if I can find an alternative modifier.
Best of luck
Phil
Re: piston rings
Didn't all rods used to feature a smallend bush once, the pin held back with circlips? I'm wondering if modifying these type of rods would weaken the eye.
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philthehill
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Re: piston rings
Les
I do not know about weakening the gudgen pin eye but Steve Harris modified the eye successfully and had a very good reputation as a 'A' series/Mini tuner and I used to race in the same class as him when speed hill climbing. I never heard of one of his engines failing.
Yes most of the engines in the past had either fully floating gudgen pins with circlips or pins nipped up with pinch bolts as per 948cc Minor. A popular conversion was to fit Teflon gudgen pin pads instead of the circlips to alleviate the possibility of a circlip breaking. I have not seen any advertised for some time now.
My neighbour who at one time owned the Triangle Special (now owned by Burlen at Salisbury and featured on their web page header) had the Hudson straight eight rebuilt and the gudgen pin circlips were accidently left out. You can imagine the damage to the bores, great big vertical scores.
I do not know about weakening the gudgen pin eye but Steve Harris modified the eye successfully and had a very good reputation as a 'A' series/Mini tuner and I used to race in the same class as him when speed hill climbing. I never heard of one of his engines failing.
Yes most of the engines in the past had either fully floating gudgen pins with circlips or pins nipped up with pinch bolts as per 948cc Minor. A popular conversion was to fit Teflon gudgen pin pads instead of the circlips to alleviate the possibility of a circlip breaking. I have not seen any advertised for some time now.
My neighbour who at one time owned the Triangle Special (now owned by Burlen at Salisbury and featured on their web page header) had the Hudson straight eight rebuilt and the gudgen pin circlips were accidently left out. You can imagine the damage to the bores, great big vertical scores.
Last edited by philthehill on Sat Jul 19, 2014 7:55 pm, edited 1 time in total.
Re: piston rings
Oh well, the proof of the pudding etc. I imagined you'd have had to increase the bore diameter by 1/8'' or thereabouts. Just been out and removed the rings from the pistons. I recall the pin pads.
Re: piston rings
The risk of piston damage is if you try to hold the piston in a vice - while you struggle to align the rod/gudgeon pin/and piston bore before the rod grips the gudgeon.... It's a job that looks like it would be easier with 3 hands.....one of them 'heat proof'.