GiSelle the GS Mechanical Refresh Mark 2

OK, I took a brief break from the keyboard to do a couple of measurements.

Referring to the image below, it seems my bores are pretty much OK, since they measure the same to 2 deciamal points at the top and the bottom. I'm using a pair of digital calipers for this, but ensuring consistency of reading by lightly tensioning the jaws apart while locking the slide. Using my expanding bore gauges and then measuring with the same calipers gives the same readings, so I'm confident it's right. In any case, there doesn't seem to be any discernible difference between diameters top and bottom. (Oh, and I've scraped and cleaned the bores top and bottom as well.)

The results would seem to indicate the original rings are in fact worn at 24 to 28 thou gaps. It implies that the new rings with 18/19 thou should at least be an improvement.

Whether that cuts down the smoky substances will be interesting I suppose.

I really don't want to go down the road of replacement barrels and pistons, and quite frankly I can't justify it at all on these figures anyway.

Oh, and sorry for mixing my measurement metrics. My mind is a strange place, but most comfortable with mm for bores and thou for gaps!

Cheers, Pottsy
 

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Stop it Shane! Although, one of those little ones on the Rangy would be interesting.

Actually, I've driven a Mate's Mk 2 Cooper S equipped with a supercharger and it's simply spectacular.

It's very tempting, but I shall rise above it and retain the purist streak that lurks deep within me! (And doesn't often get out! :) )

Cheers, Pottsy
 
Stop it Shane! Although, one of those little ones on the Rangy would be interesting.

Actually, I've driven a Mate's Mk 2 Cooper S equipped with a supercharger and it's simply spectacular.

It's very tempting, but I shall rise above it and retain the purist streak that lurks deep within me! (And doesn't often get out! :) )

Cheers, Pottsy

nah ... for a shitbox range rover these days I'd find a banana shaped commonbore ute and put its LS series engine from that in there. endless reliability, cheap parts availability and huge power ...

This doesn't help getting the GS scooting alone is a crazy non-GS fashion though :roflmao:
 
Hi again Pottsy. If the bores are parallel then 18 thou should give you a marked improvement. If you haven't got a suitable hone, and bearing in mind you don't want to remove a lot of material, you might just want a Fold up half a sheet of 240 grit wet and dry and clamp it into a doubled over welding Rod, and then drive that with an electric drill a low medium speed and brisk up-and-down movement to give you the deglaze for the new rings.
Given that several GS's in the circle are now almost finished, it might be worth doing a community project to pick up on Double Chevrons idea of
adapting a modern small supercharger to a GS 1220 so that we have it worked out in the next round of rebuilds.
 
Supercharger? Sounds a bit boring…

w7Wkl2Y.jpg


Hmmm.... I'm thinking supercharger. GS's really lack in low rev torque. A supercharger will give you excellent drivability (set to say 6psi). A turbo will give you extra power at higher revs where they are already singing quite happily along. Unless its a track car I'd go drivability over outright power anyday :dance:
 
The Numbers are In! (See attached image)

As expected, they're pretty consistent across all four. Ian, I suspect you're right in regard to a marked improvement.

I have a cylinder hone, but was contemplating just a deglaze by hand with fine emery anyway.

I guess it's remotely possible these are the original rings and barrels, given what history of the car I know. Evidence against that, however, is that the ring set has a three piece oil control ring and the top of the middle ring says "top" rather than "haut". I know the car was serviced at DeJong motors for at least some of its life, so maybe they did a rebuild at some stage. Who can tell.

Just for curiosity, since the R16 replacements have a three piece control set and were made in Maribyrnong by ACL, can anyone shed light on what sort of rings were used originally? (The new ones don't have any markings, just a chamfer on the middle ring).

As far as forced induction goes, it's not really on my radar, although I agree it'd be a fun thing to try. I'd be more inclined to go down the path of EFI, however, since that would improve low end more than a little anyway. I've got a Megasquirt ECU already standing by, along with a few of the needed ancillary bits such as sensors, TPS and of course injectors. Moby Dick was going to be the initial test bed, but maybe GiSelle will usurp his authority! That's for the future however!

OK, it's off to the shed after a cuppa and a-honing we will go!

Cheers, Pottsy
 

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Great that the bores are so consistent. I guess most of the wear was carried by the rings. I expect that you have this covered, but dont forget to make sure you have a criss cross honing pattern (even with fine emery, rather that going in one direction either horizontally or vertically. I dont understand the science but apparently it makes a difference to the rings bedding properly. Ian
 
Experience many years ago with my '74 1220 showed that effective valve seals & pinned rings were absolutely essential. At that time I worked in Katoomba , parking in the main street where extreme angles towards the gutter would result in half the town disappearing in a blue cloud on every start up. Pins inserted into the pistons with rings modified to suit & motor bike seals fitted to inlet valves, solved the problem. My later '78 model never blue smoke at all on startup !
Richard
 
A very productive, and immensely satisfying day.

After finishing all the measuring and cleaning it was time to hone the barrels. A quick refresh of the memory from the Repco Engineering Manual re-inforced the need for 45 degree cross hatching when honing. I sat the barrel on the bench, squirted all inside with WD40 and carefully inserted the hone. With Ryobi san on lowest speed a back and forth motion produced an acceptable cross hatch I reckon. Maybe not professional standard but it'll do me. Once all four were done to my satisfaction it was time to think about assembly.

In case you're wondering about the bit of all thread in the photo, it was to support the con rod on the lower head studs so the piston was accessible all the way round.

Putting rings on in situ is always a bit fraught for mine, but I really didn't want to disturb the pistons any more than I had to so with a pair of handy dandy ring expanding pliers, and an old feeler gauge to protect the piston surface, it was hey nonny no and presto, the pistons all sported new (albeit Renault) rings.

Squirty bottle of oil all over the place and it's time for the next bit.

Previously I've used a split bit of 75mm poly conduit, but I decided a while back to splash out on an eBay universal kit (for motorbikes I think, but nice). Not having a plethora of hands I press ganged a worm drive clip to hold the compressor compressing while I got on with gentle insertion.

I love it when a plan comes together! All is now assembled and ready for the heads. Speaking of which, I've also carefully checked and re-adjusted the rocker clearances on the bench. Far easier than on the car! Since the heads were reconditioned with new valves, guides and seals, I've covered a couple of thousand km so I figured it was prudent to re-adjust them.

A good day's work I reckon. OK, maybe a tad slower than a pro would do it, but this is my hobby and I'm retired and in lockdown, so I can dawdle all I want! :)

Here are some progress pics. They should be self explanatory I think. I've also included the shots of the two cylinders where the top ring gap was at the bottom of the piston.

And speaking of that, Citronut, I sort of agree that pegging them is a good idea, and obviously Mr Citroen did it on early cars for a reason, but I'm hoping this rebuild will at least see some improvement without having to do any major removal or machining.

Cheers all. It's Beer O'Clock! Pottsy
 

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I guess we'll see when I get round to it :)
Oh, don't get me wrong .... I think a turbo'd GS would be unbelievable .... Its just sssooooo much less work to strap a supercharger on there :) .... I'll be interested to see how you go from the Y pipe ..... er, "H" pipe on the GS to a turbo. Maybe you could rear mount the turbo :dance:
 
A very productive, and immensely satisfying day.

After finishing all the measuring and cleaning it was time to hone the barrels. A quick refresh of the memory from the Repco Engineering Manual re-inforced the need for 45 degree cross hatching when honing. I sat the barrel on the bench, squirted all inside with WD40 and carefully inserted the hone. With Ryobi san on lowest speed a back and forth motion produced an acceptable cross hatch I reckon. Maybe not professional standard but it'll do me. Once all four were done to my satisfaction it was time to think about assembly.

In case you're wondering about the bit of all thread in the photo, it was to support the con rod on the lower head studs so the piston was accessible all the way round.

Putting rings on in situ is always a bit fraught for mine, but I really didn't want to disturb the pistons any more than I had to so with a pair of handy dandy ring expanding pliers, and an old feeler gauge to protect the piston surface, it was hey nonny no and presto, the pistons all sported new (albeit Renault) rings.

Squirty bottle of oil all over the place and it's time for the next bit.

Previously I've used a split bit of 75mm poly conduit, but I decided a while back to splash out on an eBay universal kit (for motorbikes I think, but nice). Not having a plethora of hands I press ganged a worm drive clip to hold the compressor compressing while I got on with gentle insertion.

I love it when a plan comes together! All is now assembled and ready for the heads. Speaking of which, I've also carefully checked and re-adjusted the rocker clearances on the bench. Far easier than on the car! Since the heads were reconditioned with new valves, guides and seals, I've covered a couple of thousand km so I figured it was prudent to re-adjust them.

A good day's work I reckon. OK, maybe a tad slower than a pro would do it, but this is my hobby and I'm retired and in lockdown, so I can dawdle all I want! :)

Here are some progress pics. They should be self explanatory I think. I've also included the shots of the two cylinders where the top ring gap was at the bottom of the piston.

And speaking of that, Citronut, I sort of agree that pegging them is a good idea, and obviously Mr Citroen did it on early cars for a reason, but I'm hoping this rebuild will at least see some improvement without having to do any major removal or machining.

Cheers all. It's Beer O'Clock! Pottsy

Thanks for the piccies, this sort of stuff is really interesting as I never get to do it. I do watch stuff like this on youtube


broken .... cut 'n' paste this and delete the spaces in the https :)

h t t p s : //www.youtube.com/watch?v=N-kkMUNOrBg

he talks about honing with the same tool your using from about 8:45 onward (prior to that is american motor specific stuff). imagine fidning this sort of information 10years ago ... it would have been impossible!
 
interesting you went that way on reassembly. I put the pistons in the bores first and then lined up the gudgeon pins with the cylinders resting on the mounting studs..
 
Very nice honing work. Pottsy. Please don't forget to put in the brake cooling ducts in before you put the heads on like I did. Makes for a lot of extra work.
Re the installation - Ive tried both and I found Pottsy's way was preferable. Depends on how free the gudgeon pins are I guess.
 
Yeah, I thought about removing the pistons but it was something I wanted to avoid if possible. I'd heard about the "motorbike" ring compressors so thought I'd give it a whirl, and it works fine.

I made up a tool to remove the gudgeons on my spare motor and it was quite a faff to be honest.

I'm lazy that way!

And Ian, thanks. It's taken a long time but I think I've finally got the hang of honing.

And as for the ducts, yeah, fell for that once, won't do it again! :)

Cheers, Pottsy
 
I also fit up the complete piston assemblies on the rods, then slide the cylinder on....... but I don't use a ring compressor (i do have a couple but rarely use them). As the cylinder approaches each ring, I simply push it into the cylinder tapered lead in, compressing it manually with a pair of wooden "fingers".
Quick easy reliable.
 
Another day in paradise! There's nothing quite like a sunny Winter's day to potter about getting greasy.

Today saw the heads go on, fairly straightforward, and the shrouding and inlet manifolds on.

I broke out the Copper-Eze for the head to barrel joint and the head bolt threads. Also used some rubber grease on the oil tube o-rings, just to ease their entry! (OoEr Matron!) All torqued up nicely and ready for work.

The shrouding is one of those jobs that makes you wonder what sort of mind altering substances were used by the designers, but I'm getting the hang of it now. I seemed to find all of the little M5 bolts and their matching orifices. So far so good.

All buttoned up with a new oil filter and a sumpful of cheap oil that I can use for a short time then recycle. I always reckon that when the motor's been opened up, it's a good move to flush it all through then refill with some good stuff. Any scunge I missed after cleaning up after the honing should also get flushed out, not that there should be any.

A couple of minutes with a belt around the oil pump pulley, a multimeter on the oil pressure switch and Ryobi-San on high speed saw the oil circulated and up to pressure quite painlessly. Even better, so far, no leaks!

So tomorrow will see me fitting the timing belts and front fan housing and fan. Then I'll be hoisting the beast up for ease of access and installing the exhaust manifolds . Another fun job. And I'm really not looking forward to getting at the Y-piece clamps when the time comes!

Progress is a wonderful thing!

Cheers for now. Pottsy
 

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