520 Continental rebuild

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rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Thu Oct 25, 2018 11:51 am

That is what I was told as well, I just wanted another opinion.

Thanks

jsapp
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Re: 520 Continental rebuild

Post by jsapp » Fri Oct 26, 2018 9:18 am

I have used Permatex High Tack with the silk thread on a couple cases and have had great results with it.

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John Fenner
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Re: 520 Continental rebuild

Post by John Fenner » Fri Oct 26, 2018 12:30 pm

jsapp wrote:I have used Permatex High Tack with the silk thread on a couple cases and have had great results with it.
Same here, had good luck with it, flange sealant saves the silk string for flossing :toothy7:
I never finish anyth,,,.

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Tue Nov 06, 2018 2:04 pm

I have been waiting on parts! I gat a call from Larry at D & S, my cam, rods and rocker arms are done. Abner called 30 minutes later, pistons and rings will be here by Friday, cylinders are also done. Its a good thing I did all of my yard work and took the wife to dinner last weekend, cause nothing is happening this weekend but motor work!

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Wed Nov 14, 2018 9:05 pm

Im ready to start file fitting piston rings. Is there a standard for how far down in the bore I need to push the rings to measure the gap? Also, I have 10-1 Ross pistons and P5 superior rings, should I use factory specs for the ring gaps? Should I build it on the tight side or loose.

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John Fenner
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Re: 520 Continental rebuild

Post by John Fenner » Thu Nov 15, 2018 1:08 pm

There is a formula for bore size to end gap out there, if you do some measuring to figure where each ring will set in bore up in the choke, you can get them gnats ass hair set to specs for best results.
I never finish anyth,,,.

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John Fenner
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Re: 520 Continental rebuild

Post by John Fenner » Thu Nov 15, 2018 1:10 pm

I never finish anyth,,,.

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Thu Nov 15, 2018 2:04 pm

I have file fit rings before on automotive engines, I measured down .75 from the deck. I was sure that I needed to check the gaps down in the choke rather than 1 - 1 1/2'' down in the bore on the aircraft cylinders.
The factory spec is .033 - .044 for the top and .030 - .046 on the second. I didn't know if you could / should tighten them up with these Ross pistons. Using the chart you sent, that gap would be .024 , that seems tight. Especially on an air cooled motor.

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John Fenner
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Re: 520 Continental rebuild

Post by John Fenner » Thu Nov 15, 2018 3:53 pm

Go .030, it'll be fine.
I never finish anyth,,,.

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Slidin Gator
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Re: 520 Continental rebuild

Post by Slidin Gator » Thu Nov 15, 2018 8:43 pm

rowdy1 wrote:I have a set of Superior cylinders that are take offs w/ 450 hrs. They had an AD for injector bosses or something. They are complete including pistons, pins, rocker arms, everything. I spoke to a builder this morning that said the same thing about the cam. He suggested a set of 10-1 ross pistons and build the rest back to stock. He also suggested NO Lycoming rods!
Do you have a depth micrometer gauge to check the cylinder condition over the full stroke (or take them to a shop to check)? 450 hours should not have too much bell to them, but I would confirm diameter over the entire stroke (since they are not new) to make a decision on optimum ring gap, if possible. Otherwise, you can go my way, plug and pray. It usually works, but not always...

My other 2 cents, too much gap will rob power but won't kill the motor. Too tight and she is dead. Err on the loose side, these things do get hot..
I grew up thinking I-10 was the Mason Dixon line.
1986 Airboat Engineering Inc., 14' Marsh Master. Refreshed narrow deck, SV O-540, 72” NGQ. A Bob Stossel original.

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Fri Nov 16, 2018 10:17 am

I had Moore Performance recondition the cylinders, the finish hone left the worst one .006 above minimums. According to Keith they are in air worthy condition other than the ADs. He did not look up the ADs to see what it was for. I also found a chart online that has Superior ring part #s and recommended ring gaps. Those numbers are different from the original Continental service manual. I have a small fortune wrapped up in this rebuild, I intend to be 100% on my processes.

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Re: 520 Continental rebuild

Post by rowdy1 » Thu Dec 06, 2018 3:25 pm

Project update: Bottom end is together. All rings are file fitted, all cylinders are loaded, four are installed. All parts are in hand. I spent as much to rebuild the motor as I purchased it for to begin with.
$100 to mag and polish crank
$1300 for bearings, gasket set, nose seal, ect
$2700 for cylinders + total reman. including replacing exhaust seats
$1300 to reman rods, re-bush rocker arms and H290 grind cam and lifters, re- bush idler gear
$2100 for Ross 10-1 pistons and ring sets
$250 in new pushrods
$200 for new rocker arm shafts
$300 for hydro dipped valve covers
$150 worth of paint, lubricants, solvents and sealants
$50 for pushrod spring compressor
$100 for cylinder nut wrenches
$300 for GMAC to reman the carb.
Just call it $9000, but I haven't touched the oil pump yet!

Gary S
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Re: 520 Continental rebuild

Post by Gary S » Fri Dec 07, 2018 7:41 am

You will have a sweet running motor when your done.

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Sun Dec 16, 2018 3:15 pm

I spent this weekend bead blasting and painting parts for final assembly. However, I have 2 intakes that I can not get the valve lash right on. Both are .200+. I have swapped all of the pushrods that I have and can't get there. they have slight preload but to much lash. What do I do, let it ride? Or can I take the lifters apart and adjust them?

BobBrack
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Re: 520 Continental rebuild

Post by BobBrack » Sun Dec 16, 2018 3:43 pm

You have to get longer push rods or buy 2 of the adjustable ones.

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Re: 520 Continental rebuild

Post by flcracker9 » Mon Dec 17, 2018 11:58 am

The lifters can't be adjusted. I'm not sure what the max lash was on my 0470, but I seemed to remember it was something like .250 with the lifter disassembled and completely collapsed, which seemed huge? Maybe one of the Continental guys will chime in? I had the opposite issue, my lash was too tight after installing the new cylinders, leaving me 2 options, shorten the pushrods (which doesn't apply in your case), or convert mine to adjustable. I went ahead and converted mine to adjustable, and set the lash at .090 after talking with Gary Barber (he converted my pushrods to adjustable). Before you do anything, check the specs on the lash, you may be good.
12' Open Palm Beach, IO-0470-L 260hp, 72" NGQ

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Mon Dec 17, 2018 1:50 pm

Maximum lash is .200, I think the range is .60 - .200 I have two intakes at nearly .250. I live in a world where .035 valve lash is huge, .250 is a quarter inch! I ordered adjustable push rods from Smith Bros this morning. I hope to set them all at .85 - .90 at least they will all be the same.

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Fri Dec 21, 2018 8:25 pm

Ok guys my adj. push rods came in today. I have re- read all of you posts as well as the manual on setting valve lash. I need a little clarification. Do you take the lifter apart to get all of the oil out of them? I had my lifters rebuild, they are dry, I did squirt a shot of wd40 in them for lube when I check lash the first time. In this case do I still need to take them apart and if so why? These might be stupid questions, BUT with the $$ I have invested I need to be sure I'm doing it right.

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Slidin Gator
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Re: 520 Continental rebuild

Post by Slidin Gator » Fri Dec 21, 2018 10:40 pm

Yes, you take the lifters apart to dry them out. A shot of WD is fine for assembly. You said you had them rebuilt and you are sure they were dry when you got them back, so other than a shot of WD 40, you added no oil, sounds like they should still be dry.

Just one caution, if you filled up the oil and lubed up the system, then started setting lash, just turning the prop a few times can pump up the lifters. Made that mistake once, the lash kept changing when I turned the prop and checked them again.

If the sump was dry and the lifters were dry and you got the lash set all around, then call it good and move on, you ain't gonna hurt the motor. Go ahead and put the oil in now before you forget.
I grew up thinking I-10 was the Mason Dixon line.
1986 Airboat Engineering Inc., 14' Marsh Master. Refreshed narrow deck, SV O-540, 72” NGQ. A Bob Stossel original.

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Sat Dec 22, 2018 10:10 am

That's the answer I needed. The lifters are dry except for the wd40. The motor is on an engine stand, standing on its nose. No way to get oil into the lifters. (no oil pump or pan on it)

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Slidin Gator
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Re: 520 Continental rebuild

Post by Slidin Gator » Sat Dec 22, 2018 5:34 pm

Worst case if they were full of oil it would be like setting the lash to 1/2” dry. They valves would make a bunch of racket and the motor would hardly work.
I grew up thinking I-10 was the Mason Dixon line.
1986 Airboat Engineering Inc., 14' Marsh Master. Refreshed narrow deck, SV O-540, 72” NGQ. A Bob Stossel original.

rowdy1
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Re: 520 Continental rebuild

Post by rowdy1 » Sun Jan 20, 2019 7:10 pm

Latest update.
The engine is now ready to run!
I pressure primed the engine with a home made contraption so when I hit the started button it only took about 20 seconds before I hade 40 psi on the gauge. The problem is, after I put the plugs it in and tried I start it, it has so much compression the factory starter wont turn it over. I can bump it over but it will not just spin it over from compression stroke to stroke. I realize that's a good problem to have. Now, who builds a starter / alternator bracket for a sandcast block? Cause I'm gonna need one.

woodlineO540
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Re: 520 Continental rebuild

Post by woodlineO540 » Thu Jan 24, 2019 12:23 pm

Norman Clay in Okeechobee offers a really good starter alternator bracket.. in the name of his company is innovative Accessories

Striker543
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Re: 520 Continental rebuild

Post by Striker543 » Thu Jan 24, 2019 1:14 pm

I liked my dick waters (Airtec) starter. He’s in the cocoa area

adl
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Re: 520 Continental rebuild

Post by adl » Thu Jan 24, 2019 1:25 pm

Call Innovative Assessories at 863-357 3400 they had starter and alternator kit with flywheel for about 1200 . I put one on my and spin it like crazy. call if you like 3865869297. good people to deal with.

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