Build – Actual

Rather than give a blow by blow account of my engine rebuild go to Mark Langford’s excellent website and follow his rebuild from there. I will show some pictures of my rebuild with some additional comments.

Rather than build the engine in the shop along with the sawdust, I decide (with permission!!) to start the rebuild in the kitchen. I first bolted both crankcase halves together with the crankshaft and camshaft complete with new bearings.

IMG_0630_JPGCrank & Cam installed.

IMG_0637_JPGWith No.1 cylinder at TDC the camshaft and crankshaft keyways aligned as shown, together with the marks on both camshaft and crankshaft should mean that it’s all OK!

IMG_0635_JPGRight-hand bank cylinders and cylinder head in place.IMG_0640_JPGBoth banks installed. I still have to torque the rod bolts

IMG_0646_JPGGetting in to torque the rod bolts. I used a beam torque wrench and a standard 1/2 inch socket.

IMG_0653_JPGRear of rebuilt engine.

IMG_0654_JPGFront of rebuilt engine.

IMG_0663_JPGWith alternator and starter motor fitted.

IMG_0667_JPGAlternator and starter motor detail (front).

IMG_0669_JPGAlternator and starter motor detail (rear).

IMG_0674_JPGSome old waste pipe being used as the inlet manifold pattern. I intend having some aluminum tubing bent to shape. I am hoping that I can weld the bend to the flange rather than have the ‘tee’ piece as shown.

IMG_0675_JPGThe right side….

IMG_0673_JPG…and the rear view.

IMG_0677_JPGThe carb will mount approximately where the two hose clips are on the bottom tube.

IMG_0752_JPGI moved the engine to the engine mount and fitted it to the fuse to check the fit of the manifold. Needs a couple more aluminum bends and some more welding but is looking good so far.

IMG_0753_JPGThe inlet manifold in its final (approximate) position.

IMG_0755_JPGThe carb mounted in position.

IMG_0775_JPGThe engine test frame awaiting the engine.

IMG_0776_JPGI changed out the original Nippon Denso alternator for a John Deere unit.

IMG_0782_JPGThe gives a much cleaner profile and I can now get efficient cooling on both cylinder banks with properly positioned cowling “ears”.

IMG_0780_JPGTop bracket details still waiting for some paint.

IMG_0781_JPGThe bottom bracket bolt will be changed for the correct length!

IMG_0800_JPGI changed out the mounting bracket to an aluminum plate. I need to fit the tacho sender on the other side of the engine so I took the opportunity to make the brackets the same type. I borrowed the idea from William Wynne’s website.

IMG_0806_JPGShows the side on view of the new bracketIMG_0804_JPGThe tacho sender unit mounted close to the starter ring gear

IMG_0805_JPGThe sender half a turn back from the starter ring gear.

IMG_0832_JPGThe inlet manifold welded together

IMG_0837_JPGThe HD CV40 Carburetor mounted in position.

IMG_0853_JPGI modified the alternator mounting bracket to accept the oil pressure and temperature senders.

IMG_0855_JPGThe Port side exhaust system mounted in position. Needs a coat of High Temp paint.

IMG_0858_JPGThe engine with both test “Ears” attached.

IMG_0859_JPGReady now for the carb heat air box/air filter.

IMG_0889_JPGReady for its first start-up!. (Click on the images to hear the engines first run.)IMG_0920_JPGI modified the stand to make it easier to manage. (Click here to see why!!)

I have found that the Harley Davidson CV 40 Carburetor needs priming or full choke at each start up. If I put my hand over the carb mouth at start up it fires up OK. As soon as the prop blast hits the carb when I remove my hand the engine dies. Too much air I think. I will make up a choke as part of my air box to see if that helps with the starting. I think I need only the choke or primer, not both. Ignition is set to about 8 degrees so should give me about 30 degress when WOT. I also intend making the ears smaller in height so that they fit within the cowling. I also find that the starter motor doesn’t like anything except a fully charged battery. The starter motor jams sometimes if not fully charged. Could be some tuning on the timing is required.

IMG_1013_JPG IMG_1012_JPG IMG_1011_JPGChanging the timing improved the starting considerably. I also installed an Odessy Battery which has not needed charging. I have changed the carb out for a borrowed NAS-3. I also borrowed a three blade prop and the combination is working very well. Presently the engine turns static at around 2800rpm. Oil pressure is in the 45 – 50 psi , the oil temp and CHT not very high (too much cooling with no cowling?) I am thinking of purchasing a NAS-3 or MA3-SPA. The CV 40 is OK but needs a lot of adjustment and fiddling about. The NAS-3 bolted straight on with (at present) no adjustment needed. Click on these small images for some engine runs. These runs are with the CV 40 still installed