Yesterday's daily today - the J69 version

[Jon]

I am pretty much engine-specs intolerant/ignorant. When leafing through old back issues of CCC or equivalent I look at all the pictures but tend to skim read about half the text as it was pretty much indecipherable. However, with that last post of yours (accompanied with very helpful pics) I'm beginning to understand the previous four pages, which I've diligently read but occasionally skimmed over in confusion and looked at the nice photos instead. Top work!

I'm assuming this is a labour of love rather than pure economics but that rebuilding an engine to flash rather than standard spec. is justifiable if you're going to the expense and effort. I also suppose that now I've exposed myself as a mechanical FUD, I can ask how a head is actually skimmed? Lots of people (mostly K-series owners...) mention it and I can understand the necessity but what type of machine grinds the top of an engine block uniformly smooth over its entire surface? The metal equivalent of a thickness planer?!

[Jonny69]

I am pretty much engine-specs intolerant/ignorant. When leafing through old back issues of CCC or equivalent I look at all the pictures but tend to skim read about half the text as it was pretty much indecipherable. However, with that last post of yours (accompanied with very helpful pics) I'm beginning to understand the previous four pages, which I've diligently read but occasionally skimmed over in confusion and looked at the nice photos instead. Top work!

Cool, glad to have been of help!

I'm assuming this is a labour of love rather than pure economics but that rebuilding an engine to flash rather than standard spec. is justifiable if you're going to the expense and effort. I also suppose that now I've exposed myself as a mechanical FUD, I can ask how a head is actually skimmed? Lots of people (mostly K-series owners...) mention it and I can understand the necessity but what type of machine grinds the top of an engine block uniformly smooth over its entire surface? The metal equivalent of a thickness planer?!

Yes, this build isn't very economical in terms of horsepower per £! I'd get about 50% more power out of a 1700cc crossflow for the same cost, considering it's a direct swap. Even the conversion parts for a 2 litre Zetec would have probably come to less and it would have been more powerful, more reliable, smoother, more economical and easier to start. I've spent maybe 30% more on machining than a normal full rebuild by adding the tuning work, but bear in mind I've already got the Webers and manifolds which then add a considerable amount to the cost of a build like this.

Head and block skims are usually done on a vertical milling machine. Bigger machines (or places that have spent a lot of money on tools) might have a large cutter dedicated for the job, but others use a fly cutter which can do a wide sweeping cut and you get a nice flat surface. Some places grind the surface as well, but it's not necessary in my opinion if the final cut is done slowly and is nice and fine. Grinding is done on a surface grinder which looks a bit like a mill but with a grinding wheel and a fast-moving bed.

[I.K.Brunel]

Brilliant!
Every day is a school day with J69!

[Jonny69]

I got to do a bit of engine building over the weekend - about time, because it's been sitting on the bench in the shed for over a month! No matter, I've come back from Bonneville with renewed enthusiasm and I'm keen to get on with it despite knowing that there are going to be a few fitment issues upcoming. Yesterday I fitted the cam, timed it up using a vernier timing wheel and fitted a few components. I've not touched anything car-related in quite a long time so I was being a bit ham fisted at first, plus cam timing is a frustrating job at the best of times and it was trying my patience at times.

First thing to mention when assembling engines is you need to generously oil almost everything and so I thought I'd smugly post a picture of my trusty aerosol can cap I use to hold a bit of clean oil and my 1" brush for painting oil on components, bores etc:



Naturally, it wasn't long before I knocked it over and there was oil everywhere. Predictable. It happens every time and note the lack of a comically placed ironic asterisk, because it's really annoying when it happens.

These are cam lifters, also known as followers or tappets, I don't know which is the correct term and I thought they looked pretty much the same in all engines where the cam is in the block until I looked them up and they don't. But they do the same thing. The lobes on the cam push up and down on the wide pads, the pushrods locate in the other end of them and in turn push the rockers which push the valves open:



They need to drop into the bores in the lifter valley inside the block. You can see here that the far one in the block has had to be clearanced slightly because the cam has a higher lift than standard and the heads on the lifters are slightly thicker than the original ones:



You just oil the stems and drop them in like so:



Then you can carefully slide the cam in, fit the securing plate and timing gear, line up the marks and fit the timing chain and the job is done. On a tuned cam you're not supposed to use the standard timing gear because it can be a few degrees out and it'll affect your power. Instead you use a vernier timing gear which allows you to adjust the cam timing +/- before locking it dead in the correct position. I thought I'd show you the process since it's not every day you have to do this. The process is actually quite simple - you find the exact top dead centre point, you turn the crankshaft round to the angle at which the cam manufacturer has specified that the inlet valve is at maximum lift, turn the cam until maximum lift is found, then lock it all off. You just need a timing wheel and a dial test indicator (dti) to do it.

I set the dti in a magnetic base so that the piston would push the stylus as it went over top dead centre. You can turn the crank back and forth and watch the needle go back and forth as it goes over the tdc point and then you can pick the true tdc in the middle of the dwell where you can turn it a bit and nothing happens. There was no dwell on mine because everything is new and tight, so I just set it at the maximum height:



You then zero a timing disc on the crank, which is effectively making a small pointer out of a bit of wire held down by a bolt somewhere convenient on the engine, then tightening the timing disc so that the pointer points at zero. Mine is a bit of wire coat hanger:



To set the timing you turn the crank in the direction of rotation by the angle specified by the cam manufacturer, in my case 106 degrees:



Then you need to use the dti again to find the point of maximum lift for the inlet valve on no.1 cylinder. I used a pushrod wound in tape to stop it moving from side to side in the bore, because the probe on the dti isn't long enough to reach the top of the lifter:



And that's* pretty much it. Except on a new engine where everything is tight, you can't 'just' turn anything because it doesn't turn doesn't turn doesn't turn suddenly turns and turns past your desired point and you end up doing everything seven or eight times or more before you get it in the right position and it was this that was getting on my tits after a while.

I put a few other bits on, but I spent most of my other time cleaning things. Where the old engine was a bit leaky and oily, it means everything is utterly filthy and needs a lot of scraping and cleaning before it's good enough to go back on. I've decided I'm going to paint the block and head while it's accessible - no point rushing it now to get it back in - and I'll go for a dark grey. I know I could get a few more horsepower out of it by painting it red, but dark grey looks old-timey and doesn't show up the crud half as much. It's one compromise I'm willing to give. I even decided I'd paint the sump, which is a first for me, so here it is after a damn good going over with the knot wheel on the grinder and ready for paint:

[Jonny69]

A couple of weeks have gone by which include a week away. I may as well keep this updated since I have actually spannered some stuff. I painted the block and head in satin black and the sump in gloss black. The Hammerite went on so badly with a brush that I decided to spray the sump instead. The bonus of gloss is that oil wipes off it easily and I'm quite a fan of anything that makes my life easier.

There was a small chance I'd be able to get the car running and get it to Goodwood. I essentially had all the evenings last week to do it, but I got scuppered by the weather. Monday night I got caught up doing something else, probably making a few tweaks to my bike so I could get to work reliably, but I managed to get everything in order ready to go. Tuesday night I screwed on a load of ancillaries, taped over the top of the block so nothing could fall in and placed everything ready to go so I could get the engine in the car on Wednesday. Wednesday evening I spent a frustratingly long time trying to figure out how my engine crane went back together. DON'T get one of the Machine Mart cheapies, they are fiddly and annoying. I bought it because it's the lightest one they do, but it actually makes no difference because it's still too heavy for me to lug around comfortably. Then I realised all my lifting straps were in the back of her car and she'd decided to go shopping before coming home. It all sat outside in the dark for a while and I eventually got it back in the car and bolted up at about 9:30pm. It pretty much slid straight onto the splines first time, so expect me to be moaning on here soon because I've forgotten to do something. Thursday night it rained non-stop. Friday I had the afternoon off work. It rained non-stop. So coupled with the fact that I don't know where my modified throttle linkage for the Webers is, the exhaust still needed re-modifying, whole host of stuff still to screw on, battery not been charged since April, still not able to tell if the manifold will clear the steering, 60 mile drive on an engine that's not been run yet followed by at least a 45 minute sit in traffic like last year on a tight engine not run in, can't remember how to wire up the electronic ignition in the distributor... I decided to abandon and go for Plan B for Goodwood.

Oh wait, there wasn't one.

[Vulgalour]

This sort of story makes it very apparent to me that there should be some sort of government benefit scheme for people with worthy cars to be able to claim a grant to get a well lit dry garage in which to sort their vehicle. That sort of thing is important.

[Jonny69]

I think it was raining on Tuesday night as well - there was a reason why I was doing what I could in the shed and not outside.

[Jonny69]

Still off the road due to lack of time and parts not fitting. Latest shiny bit that cost way too much to get over a clearance problem:



I think I can safely say that this 'rebuild' has got way out of hand now.

[Seth]

A lovely bunch of bananas you've got there Jon.

[Jonny69]

Very kind of you to say so! I'm hoping the weather is going to dry up a bit at the weekend so I can fit a few more bits up. This is another thing that regularly works against you when running old cars - the weather