By Kiyoshi Hamai

Chapman Report – June 1979

The saga begins on a sunny morn, slowly rounding a neighborhood corner and a Sunnyvale police aiming his little black microwave speed detector at me. Upon gently accelerating out of the corner a semi-loud, sharp clacking noise commenced, emitting from the general area of the ENGINE. SHAZ-BUTT! Pulling over and listening, I thought and hoped it was a broken rocker or bent push rod, as it sounded much like having a half inch of valve clearance. Limp home, luckily only a few blocks. Pop off the rocker cover of the Renault engine, and again, SHAZ-BUTT! Everything looked okay. Drain the coolant, disconnect the wires and hoses, etc… crack the head off… (Suggestion to Europa owners, when going any further than removing the valve cover remove the engine lid by removing the pins from the hinges. It saves many bumps on the backside of your head.) AGAIN… SHAZ-BUTT! The combustion chamber and the piston on the #4 cylinder were peened and had funny bent pieces of metal embedded into them. And… there was a small hole at the edge of the piston. ARGG!!! A broken ring.

Pull off more wires, drain the oil, set up a block and tackle to a ceiling joist, drop the transaxle, take the weight off the engine mounts and remove the mounts and lower the engine to the concrete floor. All in a half days work. One of the beauties of an aluminum block engine can really be appreciated, LIGHTNESS.

Next started the accumulation of parts. With 75Kmiles on the engine a complete rebuild was logical, so with the help of Jeff Hawkins at the San Jose BAP, George Strother, Dave Bennett, Judy Johnson at Jim Loose and hours on the phone the search began. A point, the block, crank, rods, timing gear are Renault so bearings, timing chain, seals, and gaskets are easily attainable from BAP. But, the cam, pistons and head are Lotus. So, valves and springs are Lotus, pistons, rings and clutch are Lotus – Ferodo 200D. The head is a wedge head requiring domed pistons and not the flat top R16. Nor can R17 pistons fit because they are made for a hemi head. The head was reworked at Heads Unlimited in Santa Clara, a typical machine shop which could supply the muscle, but not the parts. The bad pits were welded and ground, the head was cc’d, valves and seats ground, springs checked, fortunately no parts were needed. Please beware that the head should not be milled more than 0.012". This is because too much shortening of the head will throw off the alignment of the valve tappets as they ride over the cam.

The bottom end of the R16 is very strong, the 5 mains really do their stuff and my crank was scoreless. Rod bolts, rod nuts, and flywheel bolts were ordered from Renault. The block was stripped and boiled out (make sure they know it’s aluminum). The water pump was replaced and with everything apart I replaced the U-joints and clutch.

The pistons and sleeves are a story in themselves. Remember the pistons are special Lotus parts, which implies trouble. A word about the stock pistons, they all crack at the skirts. So, even though I had only 1 bad hole I wanted to replace all the pistons and liners. Finding a matched set of pistons and liners is probably the easiest way to go and can be gotten from Franco American, John’s Imported Car Service (best price too), or Motorsports East. An alternative which is a bit more time consuming is to have pistons built by Jahn’s about $40 each and $40 ring set plus having your liners bored and honed by a VERY good machine shop. Rod bolts, rod nuts and flywheel bolts were ordered from Renault. Anyway, after the pistons arrived via Russia, Siberia, Outer Mongolia and Taiwan, they were installed with heat at the machine shop.

The engine went back together very easily, as it is a rather simple engine. The only word of caution is to be very sure the head is on straight. Other than that, the oil pump was weak, so it was rebuilt and the distributor was rebuilt as well. The water pump mounted, the starter check and cleaned. The engine was installed the next day. Total elapsed time from breakdown to being back on the street, 8 weeks; 1 day teardown, 2 weeks of part accumulation, 7 weeks of waiting for UPS to find the pistons and liners they lost, 3 days of assembly, 3 weeks of me too busy to do anything.

So folks, I have a new car, new engine, new paint, any offers? Below is a cost breakdown for the parts. Please note prices vary from shop to shop, as does availability (ed note: please take in to account the date of this article).