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1971 Series IIa 88" Overhaul

My mate dropped by and brought a Sunnen AN-604 portable hone mandrel - which is perfect - and a set of A45 stones, which is not exactly perfect but maybe close enough. Beggars can't be choosers.
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Standard bore diameter is 3.562" so a 0.030" oversize should theoretically be 3.592". That seems to work out as the piston skirts measure 3.590" so with the 0.002" clearance called for in the manual adds up right. I bored the cylinders to 3.586" which leaves 0.006" to hone out. I probably should have left half that but this is my first try at this and I reckoned it's better to be safe than sorry.
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Well... right now I'm feeling more sorry than safe. Ha! That six thou is quite a bit for this equipment. I'm glad now that I decided to bore most of it away because my original plan was to hone it all by hand and that would have been nasty. The A45 stones are 150 grit which from what I've read was good for roughing but these are cutting slowly and leaving a rather fine finish. Maybe it's because the stones are aluminum-oxide (for steel) where I should be using silicon-carbide (for cast iron). It's what I got...
The first 0.004" came out relatively quickly but that last two thou was quite a fight. I think rather than wracking my body for the next ten hours I'll leave it till tomorrow and see if I can locate some coarser stones to speed things up a tad. At least bore #1 looks nice! 😁
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The thought of going to all this work and expense and using Britpart pistons is also weighing heavily on me. I really, really want to put this engine together but I've decided to order pistons from Turners instead. I'm also going to look into name-brand rings like Hastings or something like that. It's a bit of a bummer though because with all this online parts ordering the inevitable happened and my credit card was compromised so now I have to wait for a new one. That plus two weeks of delivery from Turners is going to delay my engine reassembly a good month. Oh well... there's plenty of other work to do while I wait.
So that's where I'm at right now. It's all quite good really. The machine work was successful, the honing is going reasonably well, and with the decision made on better quality pistons and rings I can sleep better knowing the bottom end of this engine shouldn't give me any trouble into the future.
 
Guitar Mick said:
I wouldn’t have thought that was a job you can do free hand. It doesn’t look lightweight so I’m not surprised your back complained.
How long did a cylinder take to hone?
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Well with just the one set of stones which were a little too fine... about two hours including breaks. If I had coarser roughing stones to start with I'd guess it'd take about half an hour per bore.
The sprung 3-stone deglazing hones we all know won't actually size anything. These Sunnen hones with two stones and two guides will stay straight and round, which is what you need. They have a system whereupon you can incrementally open them up a bit at a time. It's not easy but if you take your time and make sure to consistently move up and down the entire length of the bore covering the whole stone you can get good results. A machine would be better of course but it is possible to do it by hand.
 
Wow thats quite a bit of kit, beats my sorry Draper thing.

How do you measure the bores so accurately, I have never been able to get a consistent reading whenever I have tried
 
helimadken said:
Wow thats quite a bit of kit, beats my sorry Draper thing.

How do you measure the bores so accurately, I have never been able to get a consistent reading whenever I have tried
Click to expand...
This type of hone uses two stones and two aluminum guides, both of which have rack teeth on their legs which mesh with a central pin with gear teeth on it. Rotate the central pin/gear and the stones and guides move in or out in unison. This keeps even pressure on everything which is what you need for straight round holes. The central pin has a keeper and and adjuster on it so you insert the whole thing into the bore, rotate the pin until the stones and guides contact the cylinder walls, then lock it and rotate the adjuster some more to put tension on it. Consistent up and down motion while running it and adding honing oil does the work.
The "hone" you are talking about is the kind most people are familiar with and is really only for deglazing polished cylinders to accept new rings. You can't really remove any material with one.
Measuring bores isn't hard with the right tools. I've got a nice bore micrometer, an outside micrometer to check it with, and the real secret - a dial bore gauge that you set a zero to with the outside micrometer. The dial bore gauge let's you quickly and easily check cylinder size anywhere along the length so you can watch for ovality and taper. I borrowed the dial bore gauge and had to return it but the picture below is what it looks like. Kind of an expensive toy for occasional use so I don't own one.
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I couldn't find better stones quickly enough and was being called on to return the hone so I just went at it with what I had. It took a lot of hard work but the block is basically now sized for 30 over pistons. When the new ones arrive I'll test fit them and will borrow the hone again for any touch-ups needed.
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I scrubbed the block with solvent to get the majority of the honing debris/paste off as the stuff is essentially grinding compound and if left in there will eat my new engine from the inside out.
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There was an alarming amount of debris built up on all of the horizontal ledge surfaces in the crankcase.
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It was pretty amazing really and the picture of the junk in the washpan doesn't really do it justice as most it came out with the rags. I'd already washed off the outside of the block so everything you see in the pan is bearings and pistons. Whew!
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Tomorrow I'll load it in the truck and take it to the carwash for a good washing with high-pressure hot soapy water. That aught to clean it up well enough to carry on. I think this time I'll wear my yellow rain gear instead of soaking myself head to toe... 😁
 
I pressure washed the block and head thoroughly, blew it off dry with compressed air, then again scrubbed the surfaces to be painted with mineral spirits. Another blast of air and it was as ready for paint as I was willing to get it. I then mixed about half-and-half Tremclad "Gloss White" and "Deep Green" rust paint to get a color that fairly closely matches a swatch I found online of the supposedly correct color for this engine.
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One coat of paint later and I think it looks quite nice. The actual color is a touch more green than it looks in the picture my phone took. Close enough! 😁 I'll do the water pump and timing chain cover tomorrow.
 
SeriesG said:
Very true. I thought it was unusual for the bores to be so worn but the crankshaft almost looking new. Maybe the previous owner was regular with his oil changes but ran no air cleaner! 😆
I also found it strange how inconsistently the bores were worn. Each cylinder was worn more on one side or part and in a different pattern that others. One might think that pistons moving up and down in machined bored would wear similarly but it was quite random. There were some pretty deep scores in #2 and #3 due to broken rings so that probably caused uneven wear. All I know is it's all gone now.
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the wear is on the thrust side of the up and down motion of the piston .. i would say hence the saying of "piston slap".. i could of course be wrong ...( a common thing ...lol..)
 
All the engine pieces are now clean and painted and I've collected them onto my work platform to get them out of the way while I wait for new pistons, valve springs, and a decent head gasket from Turners.
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I started cleaning gunk off of the the frame in preparation of installing the transmission assembly. Surprisingly the frame looks to be in excellent condition with little more than surface rust and in many places the original paint was still intact. There was however a lot of solidified dirt inside the transmission support crossmember and it took a while to poke it all out of there. I'll hit it with a pressure wash once the vehicle is mobile.
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Upon getting tired of cleaning the frame I moved the vehicle forward to give access to the rear where the gearbox is stowed.
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Time to look at the mounts I guess. I'd already ordered Britpart gearbox and engine rubbers when I came across several accounts online of how great the softer and more supple Glencoyne mounts were and fell for the idea. They weren't cheap but I reckoned it a good investment. They are substantially larger than the originals and required a bit of modification to fit but it wasn't much more than a touch of work with a hack-saw and a file. I'll know better if they were worth the extra expense once I get the engine running but they do seem to be a high quality part.
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So yeah, nothing too exciting but a bit of progress nonetheless. Tomorrow I'll clean up the frame some more and hopefully will hoist the gearbox assembly back into place with the juicy new mounts. One step at a time right? 😁
 
Any progress is progress 👍

Once painted it’s a good idea to get as much Waxoyl or preventer of your choice into the dumb irons at the front . They like to rot out from the inside and are a real mud / moisture trap .

All the chassis needs protection inside but the dumb irons are particularly vulnerable in my experience.
 
Looking at your 'transmission support crossmember' and it's crud holding abilities, what I did with mine was drill a 3/4" hole in the bottom, right in the middle. Then I welded a washer with a 1" hole round it, welded in the hole and round the outside. My thinking was that it would stop the crap getting caught in there in the first place.

My Father's 80" actually had that from new, (where I got the idea), it had the floor mounted pedals, and the master cylinder for the brakes was underneath, the operating rod and the return spring etc went through the gearbox crossmember, and it was an incredible gunge trap. He used to pour old engine oil in that hole, and it would eventually come out of the hole in the bottom.
 
I'd been putting off looking at the parking brake bell crank on the frame as I knew it would be a bugger. It was. It took a while just to get the seized up thing dismounted but that was nothing compared to the hassle I had getting the swivel pin out. Man was it stuck! Lots of heat and pressure later I did manage to save it but it was a monumental struggle. I drilled & tapped the casting for a grease fitting (as it should have been in the first place) so this nastiness wouldn't happen again. Whew! Funny how something as simple as this can take so much time to remedy. The first picture shows it in place with the gearbox before I'd removed it, the second is it up on the bench, and the third after I'd fixed it up and given it a coat of paint. The fourth is it back in place. Yes, probably too much detail...
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Looking at the frame before installing the gearbox got me to thinking that I really aught to replace that rear brake line. It is pretty rusty and doing it now would be much easier than doing it later so... I'm going to do it now. Well not "now" but tomorrow now. I'm going to hit the local suppliers in the morning and pick up some bulk 3/16 brake line and a double-flare tool kit. I've not made my own brake lines before so it should be an interesting learning experience. With the brake line replaced and the parking brake pieces in place I'll hopefully be able to drop the gearbox in later in the day.
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My whiteboard schedule has fallen behind a tad but I'm not too far off just yet. With the temperatures rising and Spring pretty much here I'd hoped to be further along on my project but it is what it is.
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Considering that I brought this beast home a scant four months ago I think I'm doing quite well, what with a full gearbox and engine rebuild mixed in there. I'm confident that I'll have it running and driving in another few weeks (make that a month...) so all is still good! 😄
 
Where does it say on your whiteboard "spend hours on LRUK"?

Oh, edits to add...that pin the transmission brake pivots on, the lever is held on with a circlip. This tends to ping off, and then the lever slides off meaning the brake doesn't work right. I've lost count of the times I've welded the washer on! (Must point out, different vehicles, not just the same one. 🤣)
 
Wow!! You had some crud under there .
Less crud for me but very liberally applied underseal on everything.

That bell crank looks much better 👍
I’ve recently learned to make brake pipes - took a bit of practice and a couple of half flares but good to do and I can now get a reasonably good flare every time .
 
I practiced making inverted flares with my new cheap-o crappy low-buck tool kit I bought locally. It works okay - I guess. Maybe. This is an excellent example of when buying a good quality tool is a good idea, which of course it always is. Just the same I reckoned that I doubt I'll ever need to do this again and spending $200 vs. $30 was a tough call. I spent the $30.
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The best flares I could get are a bit iffy but I think they'll hold. I just have to be very carefull when I do it and I should be good.
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So yeah... rebuilt parking brake swivel gizmo, a new Girling rear flex line, new hard line front to back, and a cleaned up brass T-manifold on the rear axle housing and we're pretty much ready to drop the gearbox in.
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I didn't have a lot of time to work on it tonight as I have to get up early for my paying job but at least some progress was made. Now that spring is here every little bit counts. Oh and for Big Sandy I've added an item to my whiteboard - in red no less. 😆
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