BUILD YOUR OWN MOTOR

 

Tell your buddy/wife/kid to strip that hunk of metal sitting on the floor, while you supervise with a frosty (actually you will need a few) in your right fist.

Make comments as they go along.

Tell them to clean up the mess- you would not want to get Dirty, would you?

Inschpeckt.

Have a rest, so you can stomach all.

When waking up, take a cold shower to minimize the headache.

Drive the whole katoodle to an engine shop and tell them to fix and assemble.

Collect motor Invoice and 1L Jack Daniel’s

Drink out ½ the Bottle to steady nerves

Read Invoice

Finish the JD’s

Pass out

                Sorry I could not help the joke, which is an Adaptation on “How to prepare a Thanksgiving Gobbler”. Well now to the Nitty gritty on rebuilding your shot Engine:

 

This is NOT a definite guide but my ideas on how it should be done. If you are handy with Tools and math’s- go for it.

Before Engine Removal, wash and degrease your engine bay thoroughly. Then remove Engine and while removing wires- label them as well as pipes, which you have to seal, closed. No dirt into these components please. All these parts and Bolts, put them into a separately labeled box.

Now take all the sideparts off. Carburetor & Intake- this has to be put into a closed box. Getting Dirt into your Carburetor now, will make you Cry later. Remove valve covers sump etc. until you are left with a block and Head assembly. All the while label and store the parts in separate boxes as you go along. Phonecalls at assembly time when you ask where what goes where will only earn you Laughter and Ridicule!

This is a good time to also clean parts before you store them- it helps being surrounded by willing people with steel brushes, solvent taps, dies etc. remember the stuff can lie there for months.

Now remove the head and if it is of overhead cam design, the caps as well- remember to label all caps in order and direction. If you are not too familiar with this, send it of as an assembly. Actually most machine shops will accept the motor in the basic longsub form and do the rest for you. Maybe you want to play, then carry on. Please note from now on you only have the satisfaction of doing it yourself, you will not really save money.

Now take the caps of the bolts (marked of course) and push out the pistons being careful not to mar the crank or have the piston slap the rod. These are precision components which measure in thou’s of an inch, no way to easily check your clumsiness. Finally mark the caps; remove them and the crank. Throw all old bearings away (unless you are working on a rarity then keep them as samples).

What needs to go to the machineshop is the head, Crank, Rods and all caps with Bolts (I normally reinstall them in their original position). The shop can get you needed parts, or your agent or the parts outlet- parts needed can be: Pistons and rings (oversized), Bearings (Oversized), Valves and guides, followers, Gasket set, Cam and bearings, Timing Chain, Oil Pump and Pickup. You are probably tired of hearing “Goedkoop is duurkoop”.

When you get the parts back check to see if you have all that is needed. Nothing is worse than having an Engine stand open for Days because you are waiting for parts. Once you are ready for assembly, give yourself time and space- such a job should be done at once. What separates the men from the Boys is cleanliness and accuracy- in that order. Wash out the block with warm soap water (a gun brush works great on oil passages) and really get stuck in there. Then Blow it out thoroughly and inspect it if any dirt or hairs etc. is left. Thereafter spray it with a light Rust inhibitor such as WD40. Next is the crank and Main caps- do not forget the oil holes- imagine you are a child in a Mudpool, yes that much Soap Water. Finally the Piston Rod assembly making sure the Piston does not slap against the rod.

Finally you can get down and measure clearances (Plastigage is a last resort- use Micrometers, Please!). If al is OK pop in the crank being careful to lube the Bearings and push oil into the passages with a kannetjie. I found Synthetic Engine oil to be the best- forget STP and other Muties. Gently push in the pistons having lubed the skirts but not the rings, put fuelline over the Rod Bolts to protect the crank and sleeves. Please measure Crank Sideplay before installing pistons and then Rod play. After each piston turn the Crank 360deg.+ and make sure it feels smooth. Ah yes as the nuts go on Torque each- and in the end recheck!

Finish the Bottom end until the sump is on remembering to prime the oilpump with jelly. If the Cam is block situated it should come in after the Pistons and lube the Lobes and lifter bases with the supplied goo or a mixture of 80-weight oil and MOS grease (remember MOS will clog the Oil Filter). Install the cam at TDC! Now clean the heads with soap water and also spray with oil. Remember always to wipe of the oil where a gasket or sealer goes. Bring Piston 1 to TDC with a dial gauge and check with your mark to see if it is out. If the head has a lubed cam installed make sure it is at TDC- otherwise you will buy new valves.

 Use a good quality sealant around the Oil and Water passages on the top and Block where the gasket goes- make sure no sealant gets into the oil passages. Now slap the head on making sure it fits smoothly without disturbing the gasket. Torque to specs making sure to replace Bolts that are non-reusable, ask your dealer if you are unsure. Now inspect your Job and then turn the engine over twice making sure it “catches” nowhere.

I have found it easiest to add accessories before fitting the motor in the vehicle. Once fitted check that you have enough water and “Running in oil” in the system. Then start her up unless you are able to prime the oil pump manually. Make sure someone watches the motor and checks under the car as you fire her up and bring her to 2000 Rpm. Let her run for a few minutes at 2000 and then kill the motor and inspect for leaks. Bring her up to temperature while playing with the Revs but avoid idle, and bleed the coolant system while you are at it. The oil light should stay on no longer than 10 seconds after initial startup.

 Once you are satisfied all is OK take her out and in a higher gear give the motor a 3/4 throttle burst bringing her up to 3/4 of maximum RPM at 3/4 load- do NOT lug the motor. Then coast her back in gear to use engine Braking. Recheck all and within 1000 km retorque and check your work while swapping in Antifreeze and your favorite Oil, forget additives! Please remember that few Engine shops will accept a crate of parts for assembly, so you have to decide whether you are capable of completing this project.

Running in means adhering to the 3/4 Rule the first 1000 Miles and avoid constant RPM including idle. Watch your Gauges, as they will tell you if something is wrong- no, it should not overheat but slightly higher Temperatures can be considered normal. City driving is ideal for that, allowing you to race from Robot to robot (seriously please drive safely). Thereafter bursts of full throttle is OK but you should avoid constant full throttle until the motor is loose which can take up to 20 000 Km’s or longer on low RPM engines. Of course in this Rebuild you could have swapped in performance parts, but avoid High compression pistons please!

For years we have done “performance rebuilds” which average 20 % more Power than stock, smoother running (due to balancing the assemblies). Better fuel consumption as the engines run more Efficiently and the same if not longer life expectancy than a factory rebuild. Also before you start rebuilding your current Engine, ask your dealer if they do not stock factory exchange units, such as Toyota Reman- you might be surprised at how cheap they are. Finally remember that Factories give warranties (so do I), though you have to trust your own Workmanship!