Posts: 135
Joined: 2/16/2008 From: kaneohe, HI, USA Status: offline
Mike, I did find out that those switches were made by Fromeco. I have no idea how much they were though, but for that kind of insurance, I think it would be worth it. http://www.fromeco.org/Categories/Switches/
DM
< Message edited by Lightfoot -- 5/11/2008 8:22:39 PM >
Posts: 4590
Joined: 7/21/2005 From: Greensboro,
NC, USA Status: online
I looked at those switches last night after your post. You'd have to call them to find out which one to buy, they have so many types. Am I understanding correctly that some of them use a Deans connector to arm them? That seems pretty foolproof.
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Joined: 5/25/2004 From: _ , USA Status: offline
Forgot to show the “old school” wheel collar method for an adjustable air restrictor for slowing the retraction and extension time. I don’t slow it down real slow just enough that it doesn’t slam super hard when it moves. Before installing the collar I grind the end of the set screw so it is smooth and round reducing the possibility of the screw cutting the air line. I believe that Spring Air sells a nifty adjustable valve to slow the air flow.
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Joined: 5/25/2004 From: _ , USA Status: offline
As you may recall when I ordered my TruTurn spinner for this build I had problems with Tower’s packaging and shipping, e.g. parts falling out of package, missing shipments. When I finally got around to installing the bushing it would not slide over the engine shaft. Apparently Tower sent me the correct size adapter kit but the wrong part number which resulted in the wrong bushing. I sent an email to TruTurn and the nice folks there sent me the correct size ASAP.
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Joined: 5/25/2004 From: _ , USA Status: offline
After giving the engine choice more thought I decided to tear down the engine that I tested for the Blue Angel and install one of my Nelson liners and pistons. The aluminum chrome Nelson liner is almost two ounces lighter than the stock ABC OS liner and has improved porting. That may result in an ounce or so less tail ballast too! While I had it apart I decided to replace the bearings because even though they felt and sounded good they didn’t look very good on the outside.
I expect most of you following this thread are very experienced at doing engine rebuilds but I thought I’d share my approach to the process.
My usual process is to remove the head (need to use an Allen wrench that is in like new condition to fit the bolts), remove the pump and drive washer. If the sleeve is stuck tight leave the drive washer on and install the prop. Insert a small piece of plywood between the top of the piston and the exhaust port. Turn the prop with a light force so the piston contacts the plywood and gently push the sleeve up.
After the sleeve is out turn the crank to top dead center and pull back on the rod with your finger. The piston should move to the back of the case, the rod should slide back on the connecting rod and the rod should almost fall off the crank shaft crank pin. Sometimes gunk can build up on the connecting rod preventing the rod from sliding all the way to the inside of the piston. Believe it or not, the professional engine rebuilders that I have talked to use a little heat from a propane torch on the bottom side of the piston through the back of the engine to free the rod. It sounds brutal but it has worked for me many times without any negative results. Just be careful with the heat.
Next I put the engine in an oven set to 350 degrees and let it heat for ten minutes or less. I remove the engine and hold it in a small towel and slap the back of the engine down on a block of would that is covered with a towel. Be careful. 350 degrees is darn hot!! With a good hard rap the crank should move back taking the back bearing along with it. Once the crank gets to the back of the case it should easily slide out with the bearing and you should be able to slide the back bearing off the crank shaft with a little force. I accomplish this by tapping the nose of the crank shaft on a piece of wood.
While the case is still hot I use a ½ inch dowel to push the front bearing out by tapping the case down with the dowel held against a hard surface.
After I get everything apart I clean up the case and head with Dawn Power Dissolver. Be careful that you do not leave the Dawn on the parts very long or it may tarnish the aluminum. At any rate, if it does get tarnished you can use Twinkle brand copper cream and a tooth brush to gently scrub the case and it will look like new. It takes a good bit of scrubbing and washing with hot water but the results are pretty impressive.
I do not mess with the pump other than clean it with fuel.
See images below to view the process and the images of the Nelson piston and liner kit. Unlike the OS piston the Nelson piston does not have an arrow on top pointing to the exhaust port and can be installed on the rod either way.
My new bearings are on their way from Boca Bearing and I will cover the assembly shortly.
To be continued…
< Message edited by 8178 -- 5/15/2008 2:00:21 AM >
Posts: 4590
Joined: 7/21/2005 From: Greensboro,
NC, USA Status: online
quote:
ORIGINAL: dhal22
sometimes used is better than new.
david
I love restoring used engines and I've done a dozen or so over the last several months that I've picked up cheap at auction. I will vouch for the copper cream; it works like magic!
8178, one thing I do different - and this is just my preference - is to remove the crank before heating the case and bearings in the oven. I find it a lot easier to get rear bearings out of a case than trying to get them off of a crankshaft. The crank and the bearing's inner race are both steel and expand around the same amount, but the aluminum case will expand more than the bearing's outer race. So, they usually fall out after heating in the oven. This is more of an issue with older engines with lots of castor varnish inside.
Just to show you how well the copper cream and Dawn Power Dissolver work, I bought this engine for $23 off *bay. It was covered with black carbon and castor varnish. New ring, conrod, bearings, gaskets and O-ring and it's like a new engine (I did buy the muffler from Ken Enya new).
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Joined: 5/25/2004 From: _ , USA Status: offline
The Boca bearings arrived today so I reassembled the engine. The engine with the Nelson liner/piston installed is a little over 1.5 ounces lighter than the stock ABC liner/piston configuration. Pretty decent for a used engine.
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RE: Blue Angel - Build - 
