What goes on an engine machine shop job card

Ask ten engine machine shops what goes on a job card and you will get ten answers, most of them a photocopied sheet that started life in the eighties. The sheet usually has a box for the customer, a box for the engine, and a big empty space where the work is supposed to go.

That empty space is where the money goes missing.

A general workshop job card works because a general repair is one job with one price. An engine is not. An engine that comes in on a Monday is a block, a crankshaft, a set of rods and one or two heads, and every one of those goes to a different machine, sometimes to a different machinist, and carries its own price. Written up as a single line saying "recon engine" it becomes impossible to quote accurately, impossible to assign, and impossible to defend at handover.

Here is what actually belongs on the sheet, component by component.

The header: what the counter needs

This part is not glamorous and it is the part that gets you paid.

Field	Why it matters
Job number	Your own sequence, never handwritten twice
Date in	Automatic if your system stamps it, written down if not
Customer, phone, account	Trade or cash changes the terms
Vehicle	The make, and enough to tell it apart on the bench
What the customer says is wrong	In their words, not your diagnosis
Estimate given	The number before anyone opened it
Signature	The line that ends arguments

All of it gets asked for later.

Block

Twenty-odd operations, and almost none of them are known until it is stripped and cleaned.

Strip, clean and degrease — hot tank, oven and shot blast, or jet wash
Crack test — magnaflux or pressure test
Measure bores — size, taper and ovality, recorded per bore
Rebore to oversize — and record which oversize
Hone — plateau honed to suit the ring type being fitted
Sleeve or liner — when it is past maximum oversize or damaged
Deck the block face — and how much came off
Line bore or align hone the main tunnel
Cam tunnel and cam bearings
Thread repairs — head bolt threads, inserts fitted
Core plugs and oil gallery plugs
Chamfer bores, clean galleries

The two that cause disputes are the oversize and the deck cut. Both permanently change the customer's block, both need to be on the card in writing, and both need to have been approved before the machine was switched on.

Cylinder head

Petrol and diesel diverge enough that they are worth keeping as separate lists. A diesel head brings injector sleeves and pre-chambers that simply do not exist on a petrol head, and a list that covers both ends up as a list that fits neither.

Both:

Strip, clean, crack test
Pressure test — before and again after any repair
Skim or resurface — record how much came off and how much is left in it
Crack repair — welded or stitched, and where
Valve seats — recut, three-angle, or new inserts fitted
Valve guides — reamed, knurled or replaced, and how many
Valves — refaced or replaced, and how many of each
Lap valves and seats
Valve stem seals
Springs — free length and pressure tested, any replaced
Camshaft and journals on an overhead cam head
Reassemble

Diesel additionally:

Injector sleeves or seats
Pre-combustion chambers — recut or replaced
Glow plug threads

"How much came off, and how much is left" is the single most useful thing on a head card. A head that has been skimmed twice before is a head you need to know about before you take another cut, and a year later it is the note that tells you whether the head you are looking at is one of yours.

Crankshaft

Crack test
Measure journals — mains and big ends, taper and ovality
Grind mains to undersize
Grind big ends to undersize
Polish journals
Straighten
Thrust faces
Balance
Chamfer and clean oil holes
Rear seal surface

Record the undersize per journal set. A crank ground twenty on the mains and thirty on the big ends is common, and a card that says only "reground" sends the customer to the parts counter to guess which bearings to buy.

Conrods

Crack test
Check for bend and twist, straighten
Resize big ends
Small end bushes — fitted and honed to the pin
Weigh and balance the set
New bolts

Six operations, and the one people leave off the card is the bolts. They are cheap, they are consumable, and they are the reason a rebuild comes back.

Gearbox

If you take gearbox work, it needs its own list rather than being written into a box on the engine sheet — strip and assess, bearings, synchros, seals, housing repair, and the same before-and-after measurements.

Two readers, one sheet

The card is read by two people who need different things from it.

The counter needs the customer, what was quoted and the signature. That is what a phone call is answered from and what an invoice is raised from.

The machinist needs the sizes. Which oversize, which undersize, what came off the deck, what the seat angles are, what the bore measured before it was touched. None of that means anything at the front desk and all of it means everything at the machine.

A sheet that serves only one of them gets copied into a second sheet that serves the other, and the second sheet is where the two versions start to disagree.

The measurements that end arguments

Three months after an engine leaves, something knocks and the customer is back. The conversation goes one of two ways depending entirely on what is written down.

Record, without exception:

Every dimension as found, before any machine touched it
Every dimension as finished
What was quoted, and what was found at strip that was not in the quote
Who approved the extra work, when, and how — signature, WhatsApp, email
Who did each operation

The last one is not about blame. It is about being able to ask the person who ground the crank what he saw, while he can still remember.

The strip-and-assess problem

Every engine job has two numbers. The first is the estimate given over the counter before anyone has seen inside. The second is the real one, after the strip.

Most shops lose money in the gap between them, because the extra work found at strip gets done and never gets charged — the oversize that turned out to be a sleeve, the guides, the seat inserts. The job card has to have somewhere for the second number to live, and a record that the customer agreed to it before the work went ahead. If your sheet only has one price box on it, the second number has nowhere to go except into your own pocket.

A sheet you can copy

Take the header table above, then one page per component with its operation list as tick boxes and a column for the measurement. Print it double-sided. It will be better than most of what is in use in the trade.

The limits of paper show up quickly, though. The card lives on the stand, so the counter cannot see it. Two heads off the same V8 end up sharing one line. Nobody can tell you what is finished without walking through to the machine room, and at month end somebody keys the whole lot into an invoicing system a second time.

Common questions

Should one engine be one job card or several? One job, several components. A job number belongs to the engine, so the customer has one reference and one invoice, but the block, crank, heads and rods each need their own operation list, their own price and their own machinist. Splitting them into separate jobs breaks the invoice and confuses the customer. Lumping them into one line breaks everything else. Where a component appears twice — the two heads off a V8 — track them separately, because one will be finished before the other and you will be asked about exactly that.

How much detail is too much? If a number would change what someone does next, it belongs on the card. Bore size before machining, the oversize taken, the deck cut, the undersize on each journal set, the seat angles. Things that would not change anyone's action are noise. The test worth applying: could a machinist who was not here that day pick up this card and carry on correctly? Could you answer a warranty question from it in eighteen months without ringing anyone? If not, the card is short of something.

What about the estimate versus the final price? Put both on the card, keep the estimate visible, and record the approval for the difference. The estimate is a guess made before the engine was opened and everyone in the trade knows it. What causes the argument at handover is not that the price moved — it is that nobody can show when the customer agreed to it moving. A signature, a dated WhatsApp message or an email against the extra work is enough, provided it is attached to the job rather than sitting in somebody's phone.

Do I need software for this? No. A good paper sheet beats bad software and it beats no system at all by a mile. What paper cannot do is be in two places at once, tell the counter what is finished without a walk to the machine room, or turn itself into an invoice at the end. Those are the points where shops usually decide the sheet has run out of road.

Have a look

Autolly builds job cards from templates you set up yourself, which is why the operation lists above look familiar — they are close to the ones our own shops run. One job carries the whole engine, each component keeps its own work, price and machinist, and the invoice comes off the job rather than being typed in again at five o'clock.

If you recondition engines, request early access and we will load your own job types onto it. There is more on how that works in engine reconditioning workshop software, on the front counter in bringing order to the everyday workshop rush, and on running through load-shedding in workshop management software built for South African workshops. Once the card exists, assigning job tasks to workers covers getting it onto the right bench, and connecting your workshop to Xero covers where the invoice goes afterwards.