The Carrier's back on the road.
I brazed the cracks in the two oil cooler bosses on the bell housing caused by someone ovetightening the tapered pipe fittings.
I thought piston rings were ok but a quick leak-down check with valves now tight showed a lot of leakage. So I installed new rings and honed bores. That gave me acceptable leak-down results. Bore is 0.015" oversize but rings that oversize are no longer available so I got 0.020" o/s and filed the ends.
I found the leak-down tests quite variable. If you test just before piston reaches TDC, you get better results than just after because rings are being pushed down onto lower groove face by friction and sealing better.
I found a Dremel with a thin cutting disk very good at trimming the rope packing of the front crank seal. A utility knife just chewed the rope up trying to saw through it.
I filled the pan with oil and hung the assembled engine nose-down from the hoist to check the front crank seal sealed. It didn't. I pulled the front pulley and smeared grease on the hub and reinstalled it to check the hub contact with the rope seal. There was a wide band around 6 o'clock with no contact, so that was where the oil was leaking through. I used a brass punch and tapped the groove in the sheet metal oil pan to squeeze out the rope more. That got contact all the way around and sealed the crank.
We installed the engine and took the Carrier for a quick run without the sheet metal on. It heated up too quickly and showed how important the dog house and rad shrouding is for directing max air flow through the rad and fan. With all sheet metal installed the engine ran much cooler. But it's tough to do an easy break-in run on a rebuilt Carrier engine- the weight of the vehicle and the brake steering put a pretty high load on it.
She's got much more power now and is back to being fun to drive.
Malcolm
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