Morris 8 Engine Build

[RWD3M]

Let's recap.

The bottom ring (an oil control ring) has a locating lug in the piston groove. When the ring is in the groove, it can rotate quite freely. The problem I'm having is compressing the ring into the groove whilst keeping the locating pin aligned with the gap in the ring (or, keeping the gap in the ring aligned with the locating pin).

The ring compressor I have will compress all 4 rings with ease.

Neither end of the bore has a taper (or lead-in) so the rings need to be compressed fully before the piston can be inserted into the bore.

If I understand you correctly, you can’t do that, you can’t feed in the pistons from the top, the big end won’t go through the bore, the piston won’t come up through enough to fit the bottom oil control ring.

That's correct Cobbler.

Could you remove the gudgeon pin , fit the oil control ring and insert the piston from the top of the block so the ring is into the bore then refit the Conrod/gudgeon pin before finally fitting the top rings? I once fitted new barrels and pistons to a mates VW with only basic hand tools using a similar method. I would be a bit concerned of catching the ring ends in the cut out section at the bottom of the bore although with carefully spacing the ring ends and using a decent ring compressor that compresses all of the rings it should be possible?

Conceivably yes, but that wouldn't be my preferred method. The problem is I haven't found my preferred method yet!

Fitting the piston from the top of the bore would give me better access but wouldn't help with the fundamental issue I have which is compressing the bottom ring whilst keeping the ring gap aligned with the locating pin.

It may well be that I need a different type of ring compressor but I'm not aware of one that will allow me to compress all the rings, keeping the bottom one aligned properly AND fit in the crankcase from below.

 

[minimutly]

I'll try again.
Push the piston out of the top of the bore so you can fit the bottom ring - will the rod allow it to go this far?
Edited to add you should allways have a small lead in at the top (or bottom if that's the feed end) of the bore to aid fitting. With modern thin rings even then it's sometimes difficult.

 

[Melvyn Best]

I have a set of ring compressors that are just a band of spring steel with a tag on each end that has a hole into which a special pair of pliers fit . The bands are maybe an inch wide , if your using that type of compressor it would be easy to locate the gap in the band so you can see the locating pin and hold the ring compressed while fitting the piston , either from the top or bottom of the bore. No need to compress the lower ring and the upper rings at the same time .

 

[RWD3M]

I'll try again.
Push the piston out of the top of the bore so you can fit the bottom ring - will the rod allow it to go this far?
Edited to add you should allways have a small lead in at the top (or bottom if that's the feed end) of the bore to aid fitting. With modern thin rings even then it's sometimes difficult.

Unfortunately, the rod doesn't allow the piston to come through fully. The bottom ring groove remains in the bore.

I have a set of ring compressors that are just a band of spring steel with a tag on each end that has a hole into which a special pair of pliers fit . The bands are maybe an inch wide , if your using that type of compressor it would be easy to locate the gap in the band so you can see the locating pin and hold the ring compressed while fitting the piston , either from the top or bottom of the bore. No need to compress the lower ring and the upper rings at the same time .

I don't suppose you could post a pic of them could you?

I did have a bit of an idea last night. I wondered if I could use something gooey in the groove to hold the ring in place as I compressed it that would sort of just wash out with the engine oil when running. I recall some years ago packing an oil pump (on a Rover V8 IIRC) with Vaseline to prime it and that didn't appear affect things once running.

Opinions?

 

[awemawson]

A suitably broad Ty-Wrap round the ring compressing it into the groove where you want it rotationally. Push the piston into the bore and the Ty-Wrap will slide down the piston skirt onto the con rod where you can cut it off with wire cutters.

 

[jinjahbiscuit]

As above from awemawson. That's a pretty good idea. In the past I've used a piece of shim cut to size and a jubilee clip, but a tywrap would actually be easier.

 

[Melvyn Best]

I will try to take and post some photos over the weekend. Just looked on eBay, mine are similar to some of the motorcycle ring compressors but they seem to hold the clamping pliers at right angles to the piston , mine can be held at any angle

 

[Melvyn Best]

I will try to take and post some photos over the weekend. Just looked on eBay, mine are similar to some of the motorcycle ring compressors but they seem to hold the clamping pliers at right angles to the piston , mine can be held at any angle

Hope this helps , it’s a Simple Simon piston ring compressor that I’ve had probably 45 years , don’t know if they are still available. The band sizes go from around 50 mm up to 120mm

 

[RWD3M]

Hi Melvyn,

Thanks for the pics. That looks like it could be just the job.

Half the problem I have is that the rings move in their grooves whilst I'm trying to tighten the compressor that I have.

Now to find one.

 

[RWD3M]

Things have moved on apace over the last couple of weekends, interspersed with occasional attacks on the garden I now have the engine ready to drop in.

It wasn't all plain sailing...



...but I managed to get hold of a piston ring compressor like the one suggested by Melvyn and that did the trick.



... timing gear and flywheel, complete with wire locking (how quaint!)...






...sump and timing chain cover next...



... and then the odious task of adjusting the valve clearances. I'm a big fan of William Morris but really, what a bonkers set up. The book suggests three 1/4" BSW spanners are required for the job!



Anyway, all done and it looks like I do at least have some positive oil pressure.



I had a spare oil pump drive shaft that I removed the teeth from so I could drive the pump from above without the engine turning over. Once in the car, I'll connect the oil pressure gauge up and drive the pump with a drill to see what pressure is developed. It also doesn't hurt to flush a little fresh oil through and prime the oilways.

That piece of bar sticking out of the top is just a piece of 9/16" stock with a slot in the bottom end to connect up to the pump drive shaft.

I had hoped to drop the negine back in next weekend but my dearly beloved has insisted I go with her to Gran Canaria for a week. Some people have no compassion!

Hope everyone has a great week!

Richard.

 

[Melvyn Best]

Glad you got the piston rings in OK . At least the valve clearances are adjustable unlike some of the old Ford sidevalve engines , they had a lump on the tip of the valve and used split valve guides, to reduce clearance you recut/lapped the valve /seat To increase clearance you removed the split guide to get the valve out then reduced the length of the valve.

 

[slim_boy_fat]

Good work!! There's something very satisfying about putting an engine back together.

 

[RWD3M]

...At least the valve clearances are adjustable unlike some of the old Ford sidevalve engines , they had a lump on the tip of the valve and used split valve guides, to reduce clearance you recut/lapped the valve /seat To increase clearance you removed the split guide to get the valve out then reduced the length of the valve.

Really?! That's mental!

I take back everything I said about William Morris!

 

[RWD3M]

Good work!! There's something very satisfying about putting an engine back together.

You're right Slim, surpassed only when said engine starts!

 

[Cobbler]

Glad you got the piston rings in OK . At least the valve clearances are adjustable unlike some of the old Ford sidevalve engines , they had a lump on the tip of the valve and used split valve guides, to reduce clearance you recut/lapped the valve /seat To increase clearance you removed the split guide to get the valve out then reduced the length of the valve.

If I recall, there was a tool sort of inverted tulip shaped that passed over the valve head & down into the port to drive the valve guide out! I think all side valve engines are a pain to adjust the valves, you wait until you have to do it in the car! Been there, done that.

 

[Cobbler]

There you are, found one, a e93a valve guide tool.

 

[merryman]

At least the valve clearances are adjustable unlike some of the old Ford sidevalve engines , they had a lump on the tip of the valve and used split valve guides, to reduce clearance you recut/lapped the valve /seat To increase clearance you removed the split guide to get the valve out then reduced the length of the valve.

No split guides, but Briggs & Stratton used the grind a bit off the stem, or grind the valve seat, method of valve adjustment until the end of side valve production, in about 2012. Did one last week on a ride on mower, what a pain to get the collets back on, my side valve compressor wouldn't fit, had to make a valve spring compressor for it.

 

[Robotstar5]

No split guides, but Briggs & Stratton used the grind a bit off the stem, or grind the valve seat, method of valve adjustment until the end of side valve production, in about 2012. Did one last week on a ride on mower, what a pain to get the collets back on, my side valve compressor wouldn't fit, had to make a valve spring compressor for it.

If you don't do many it's probably not worth buying the proper one - link

 

[slim_boy_fat]

There you are, found one, a e93a valve guide tool.

Ah, the e93a - my first car....what memories.

 

[Cobbler]

Ah, the e93a - my first car....what memories.

They don’t make ‘em like that any more ................... damn good job too