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I'm reassembling my Aerovee 80 hp and have 2 questions:
1. I didn't remove the cam gear from the cam when I disassembled the engine. Should I remove it, apply fresh locktite and retorque it or just leave it alone. I'm not the original builder.
2. As I reassemble the conncting rods, do they go in a certain order on the crankshaft? The assembly manual doesn't say.
Thanks.

If the engine was involved in a prop strike (I think your other posts said you nosed the plane over during taxi) then it should be removed and FPI'd. You may find that a new cam and gear is cheaper than the inspection though.

Are the connecting rods and crank new? If so then they can go anywhere but most people try to match connecting rods, pistons, and pins so that they all have similar assembled weights. If the connecting rods and crank are being re-used then you want to install them back to the same piston and crank journal as they were before. If you aren't sure which one went where or only one of the two (crank or connecting rods) are new then you will want to get some plastigage to measure the clearances between the bearing surfaces to make sure everything is within tolerance.

Also, the above is just my opinion. I would recommend calling Sonex to find out what they suggest.

Keith
#554

kmacht wrote:If the engine was involved in a prop strike (I think your other posts said you nosed the plane over during taxi) then it should be removed and FPI'd. You may find that a new cam and gear is cheaper than the inspection though.

Are the connecting rods and crank new? If so then they can go anywhere but most people try to match connecting rods, pistons, and pins so that they all have similar assembled weights. If the connecting rods and crank are being re-used then you want to install them back to the same piston and crank journal as they were before. If you aren't sure which one went where or only one of the two (crank or connecting rods) are new then you will want to get some plastigage to measure the clearances between the bearing surfaces to make sure everything is within tolerance.

Also, the above is just my opinion. I would recommend calling Sonex to find out what they suggest.

Keith
#554

Thanks for the info, Keith. Yes, I'm the one who had the prop strike. I had the crank magnafluxed with no damage noted. I was never told to replace the camshaft as well. I'm replacing the cylinders and pistons (bought a new Maule jug kit), as well as new heads/valves from Sonex. I'm reusing the connecting rodsI don't know the order they fit on the crank, so you're suggesting putting them in any order and use plastigauge to measure clearances. I will do that. Thanks, again.
Ken

kenandkatie2 wrote:Thanks for the info, Keith. Yes, I'm the one who had the prop strike. I had the crank magnafluxed with no damage noted. I was never told to replace the camshaft as well. I'm replacing the cylinders and pistons (bought a new Maule jug kit), as well as new heads/valves from Sonex. I'm reusing the connecting rodsI don't know the order they fit on the crank, so you're suggesting putting them in any order and use plastigauge to measure clearances. I will do that. Thanks, again.
Ken

Hi:

I had a prop strike 2.5 years ago. I replaced the crank, all bearings (crank and rods), timing gear (though I'm pretty sure mine was fine), prop hub (the woodruff key sheared off in the groove of the crank and so the hub and crank end were damaged when it spun on the crank). No need to replace the cam shaft.

As for the pistons and rods, the rods and caps should always be kept as their original pairing and orientation since they are machined and balanced to work with one another. Other than that it does not matter what order you put them on the crank. Since I was reusing my pistons, rods and pins I did make sure they went into the same location in the case.

Thanks for the info, Mike. Now, my problem is getting the crank to turn freely as I put the 2 halves of the case back together. It spins feely until I torques the bolts down, and then it won't move. I've double-checked both the cam and crank bearings, and they seem to be fitted in right, so I'm stumped.
Ken

I had hours and hours of fun with the same issue... the little bearing keepers being properly seated are one culprit... if memory serves me, I think I even had one that was too long...

Here is a thread with pretty much everything you need to know on this subject.

viewtopic.php?f=7&t=2470

Bruce,
You were right. Improperly seated bearings! GRRR!

WELCOME TO MY WORLD!

I'm glad to know that I'm not the only one who spent time going WTF! I had to elongate one of the locating holes in one of the main bearing shells as the locating pin seemed to be in the wrong position. In my cases the main shell was a couple of mm too high on one side initially. It is certainly different to assembling any other motor that I have repaired. I did enjoy the challenge of it though, although I haven't checked my medication for a while now!