Rebuild or buy?

My RV-4 salvage project is/was nearing the end of the re-build and just about ready for the engine start when we discovered that all the accessory drive gears were pitted and corroded due to the previous owner never flying the plane and not preserving the engine. After pulling a jug to look at the inside, the camshaft lobes were also pitted and corroded.
Now the engine, an 0320/E2G only had 400hrs SMOH (1991). After a complete tear down it appears the crank is ok and the top end looks good. But it will need a new cam, drive gears, oil pump gears to comply with AD, and the tappets need refurbished. I'm sure it will need other parts not mentioned. My question for the engine guru's is, what would be the best route to take? Rebuild the bottom end or sell what I've got and use the money towards a mid time salvage engine? My budget either way is around $5,000. This was not anticipated in the original plane budget.

With that budget, and the known condition of the engine that you already have, I would recommend that you repair you're engine. No guarantees on a used engine if you went that route, and also would surely cost more than it would to repair the one you already have.

I haven't got a parts list together yet, but just a few of the items I have looked up looks like the cost can add up pretty quick. If I do rebuild I want to use as much of the old parts as I can. The crank and tappets would be sent out for inspection and refurbish. I found a yellow tagged cam for $475 along with the serviceable gears I need from ENParts out of Dallas. I also would like to go with 8.5:1 Pistons. Even though I have experience with car engines, I would definitely get an A&P or someone with Lycoming experience to put it all back together. I assure you that I would not risk safety in order to stay within a budget. If it cost more then it is what it is.
One more thing, the engine log is practically empty. I guess being an experimental it really doesn't matter much, but the original owner was not much on documentation. I only know that the engine was rebuilt at the same time the airframe was built. That was 1991. The engine did way more sitting than running.

Parts

I think you can do better on the cam. First check to see if your cam can be reground. If not check with some of the airboat people in Florida.
The killer item will be whether the crank passes the 505 inspection. If it doesn't and is no badly pitted, I would consider using it anyway if you are using a wood prop. Some people claim there has only been one crank failure worldwide that could be blamed on rust. There are probably hundreds of cranks in use in EAB that do not meet 505.
I have good plain idler gear and tappet bodies, also connecting rods for sale very reasonable. PM me if interested.
Check with Dart Aircraft in Waco TX for parts. They sell both Superior and ECI. dartaircraft.com 888-753-1810
You will need heavy wall piston pins for the 160 hp pistons.

Rebuild?

I have a some gears and other accessory case parts. Some used in good condition others are overhauled. Will sell very reasonable.

Don Broussard
[email protected]

RV 9 Rebuild in Progress

Rebuild

The standard is a "New Limits Overhaul". For that to happen you need the Crank yellow tagged,the case sent out and yellow tagged.Same with the rods.These are the big three make or brake it items.The cost of these tags if everything passes with shipping $2K.Another1K to go over and freshen the cylinders and the other 2K to go through everything else.Its the cost of getting everything on the bench specked out and ready to assemble The labor is a small part of the price.Unless you buy new,you might as well rebuild what you have.I have a lot of NOS lycoming parts,so email me your list and I'll see what I can do.
RHill

OK, I know I'll catch a lot of flak for even considering this, but Jim suggested maybe checking into using an experimental/airboat cam. As long as this is an accepted alternative and is safe to do, I'm fine with this. I saw some on eBay that will fit the bill, but they mention that they are slightly under aircraft specs, but otherwise good. How does this effect performance or safety? From what I can tell it just means that the lobes are ground a little more than what the book calls for so the lifters won't open the valves as much as specified. Am I correct on this assumption? I'm sure the crank will pass. There's no pitting or corrosion, and the bearings are not scored. The crank only has the normal wear marks you would expect and should polish out and still be within specs.

NO DON'T DO IT

NO,NO,NO.............DON'T DO IT... There are things you can buy on ebay,but please don't wast your limited funds on a known bad part.know who your dealing with on ebay,I've meet some really good people there and some real low life also. I bought a set of engine mounts cure date 2/14 for a good price this summer,when they got here they were old mounts re boxed in new box's,I called him on it and he refunded through ebay including shipping,then sold them to someone else for the same money on ebay who may have never opened the box and checked the cure dates embossed in the parts.I'll pm my number,give me a call,I love to talk RV anytime my wife will let me.
RHill

I had pretty much the same situation as you. I bought a core for 5K and pulled a jug to look inside. The cam was starting to pitt so had my trusted A&P shop tear it completely down for overhaul. Cylinders were bad...replaced with new lyc 8.5:1 assembleys, crank overhauled, cam came back yellow tagged, cases done, gears done, all else new. Re assembled and ready to go (minus fuel pump) for $14K. Yours should be much less expenseve as long as the jugs are good. I think you'll find yourself tempted to do the full o/h as much as it hurts...it's good piece of mind....but a repair within your budget is possible.

acam37 said:

My RV-4 salvage project is/was nearing the end of the re-build and just about ready for the engine start when we discovered that all the accessory drive gears were pitted and corroded due to the previous owner never flying the plane and not preserving the engine. After pulling a jug to look at the inside, the camshaft lobes were also pitted and corroded.
Now the engine, an 0320/E2G only had 400hrs SMOH (1991). After a complete tear down it appears the crank is ok and the top end looks good. But it will need a new cam, drive gears, oil pump gears to comply with AD, and the tappets need refurbished. I'm sure it will need other parts not mentioned. My question for the engine guru's is, what would be the best route to take? Rebuild the bottom end or sell what I've got and use the money towards a mid time salvage engine? My budget either way is around $5,000. This was not anticipated in the original plane budget.

Click to expand...

If the case, crank, rods, and cylinders are good, you're 90% of the way there. The new parts you describe should be well south of your $5k budget, and once you're done with the bottom end, you'll have a "known" bottom end.

Rebuild what ya got

Arlie, Your engine is a "known quantity". Buy another used one and you might get the same result as the first. I'd be inclined to call D&S Cams to rebuild your cam and tappets. Get oil pump gears and gasket set from ECI or Superior. Drive gears not sure where to get those.

Heinrich

Top end

Well, more bad news. After pulling the valves, the #3 exhaust valve is bad and #1 cylinder had some rust on the bottom side and it would not hone out. So I guess it's off to the cylinder shop and dig a little deeper in my pockets. I guess this repair is going to turn into a major overhaul.
The moral of this story is, be careful when buying a used plane. Especially if it is an older RV with few hours on the engine and airframe. my plane was apparently set up for an extended period without any engine preservation. This proved fatal to this engine.
I would like to thank fellow member hgerhardt (Heinrich) for helping me indentify this major malfunction. just because it was low time I assumed everything was fine.

Rebuild

We've just done a similar exercise for two engines here. I realise this may be unpopular with some of our more experimental folks, but you only have one engine. In life the cheap way is normally the long way and costs more in the end. Certified engines have a low failure rate. If you start doing things on the cheap and installing rejected parts you loose that protection. Leave the dud parts to airboat guys and build yourself a reliable engine.

If you ask around I am sure you will find that few reputable shops in the US use reground cams and lifters. The reason is they are hit and miss. We have a Continental here that has 400 hours on it, and the reground lifters are already spalled.

Saving money on the top end is a better idea. Cylinders are easy to change and we only run 100 or so hours per year so getting 1000 hours our of one is still 10 years flying. Give the ones you have tickle and run them some more if the bores are OK and still have choke. Just make sure they don't have cracks as that can lead to destructive engine failure. If the units you have need a lot of work it might be better to buy new. New pistons, pins and rings would probably set you back $300 ea so anything more than a light hone might make me consider replacement. New ones are $1050-$1100 each, so I would hesitate to spend $600 ea on overhaul.

A set of all new parts from someone like Airpower to do the bottom end runs to around $3000. That includes all the mandatory replacement parts, piston pins, oil pump, fuel pump, Lycoming Cam kit with lifters, plungers, caps and assorted hardware (lock washers , castellated nuts etc). The cam kit is $1400 of that. Do you want to risk redoing all that work and replacing all those parts to save $500-$600?

To me, there is so much work to tear down the bottom end that it doesn't make sense not to do it properly. Cams are cheap, but the work required to fix them when they go bad isn't. You might as well replace the mandatory parts on the bottom end, call it an overhaul and know it is good for the next 10-15 years. What you have is 24 years since overhaul.

Depending if they are ECI, Superior, Lycoming parts you buy you will get some kind of a warranty this way too. You can sell your existing parts to the airboat guys and save a bit.

The three gears you need are around $150-200 each assuming you are happy with ECi. Be grateful it is not a 540. Some of those gears in them go for $900.

Hope that helps...