H2AD Baffles

Lionclaw · #1 11-11-2009, 07:23 PM

I'm working on the baffles on my o320-h2ad powered 9a. So far I've been pretty happy with how they fit considering the engine is quite a bit different.

I do have a few issues though:

1. I had to add a joggle around the filler tube. Will there be any issues putting the rubber on top at the joggle? Any problems with the oil door opening right on top of the baffle?

2. The baffles don't fit the contour of the engine very well. Would making small filler pieces of aluminum and riveting them on be ok? How close should the metal come to the engine? Fill small gaps with high temp RTV?

3. The edges of the upper engine mounts are pushing in on the baffles slightly. Should I add a double here, or strips of nylon to prevent damage?

All pics here: http://picasaweb.google.com/pilotandy/RV9AH2ADBaffles#

Any help is greatly appreciated!

airtractor8 · #2 11-11-2009, 09:48 PM

Hi Andy

Arh...those baffling baffles...I remember the same issues when I fitted the H2AD to my RV6 project. I did it a little different.

1. I did not have a joggle around the oil filler neck. I completely remade that right rear piece so that it was flat and would butt right up against the rear of #3 cylinder.That allowed this piece to lay in front of the engine Boss/casing that is shown in your pic #6&7. I also had to shorten the #3 cylinder end/top plate and bend a 90deg. flange on it to attach to the rear plate. The reason for this is two fold,this fixed the oil door baffle seal problem and also allowed the oil cooler to be mounted on the flat surface right up against the cylinder so it would be clear of the engine mount. The oil filter adapter has the hose fittings facing the right side of the engine so mounting it on the right made sense(same as the c172). I also made a doubler for the end plate and a .061 plate for the cooler opening. Have you given some thought to the oil cooler size and location? I tried the firewall setup from vans with the standard 0320 cooler fitted and run with 3'' scat. This proved totally inadequate so I changed to the larger positec type for the 200hp engine and moved it to the right baffle and oil temp now runs at 185/200 in all weather. I found out latter that the C172n that these engines come from is standard with a SW 599 cooler. The small bracket that you show in pic#3 gets remade from some .061 angle and is fashioned to be riveted on and pick up that open 1/4 hole in the middle of the pic. Also keep in mind that the cutout in the top cowl for the oil door only has to be about half the size as that specified by Vans because the filler neck ends up being about 3/4" below the top cowl and you don't have to reach around inside to top up with oil like the other engine models. If the opening is small enough you should be able to run the baffle seal material in front of the opening.

2. Your fit to the engine contour is ok and as you say a little high temp RTV and they should be fine. The left forward section of baffle will not fit at all so I just riveted a section on to accommodate the different crankcase shape.

3. I had the same issue with the left upper engine mount. I modified that piece so it laid forward a bit and would lay flat against the engine mount boss were the bolt comes through. That left piece is a very tight fit, I also had to notch a section to go around the lower part of the cylinder flange and have to remove the Lord mount nut and bolt enough to remove that part of the baffling. I fitted a 2" scat flange to that piece so I could run air to the cabin heat muff.

I hope you can follow what I mean. I could pull the top cowl and take some pictures for you if you wish?
It took me many hours to figure some of this stuff out at the time so I know what you are going through!!
Wait to you get to the front half!!

Regards
Graham
RV6 H2AD 200hrs

Lionclaw · #3 11-13-2009, 08:55 AM

Thanks for the tips Graham. The front is indeed interesting! I'm going to have to reinforce some of the areas where I carved a bunch of material away. Did you go around the mount (I'm assuming governor mount?) on the front like this?

airtractor8 · #4 11-14-2009, 09:27 AM

Quote:

Originally Posted by Lionclaw

Thanks for the tips Graham. The front is indeed interesting! I'm going to have to reinforce some of the areas where I carved a bunch of material away. Did you go around the mount (I'm assuming governor mount?) on the front like this?

No, you can't go around the governor mount like that. The governor mount as well as the fuel pump are already to high for the top cowl to fit and require cutouts and "bumps" to be glassed on to allow the top cowl to come down to meet the bottom. The only way is to mount that front piece more forward. I made mine in two halves and made brackets that picked up on the bolts/threaded holes in the crankcase parting flange, governor pad & fuel pump to hold it on.

Anyway, they say "a picture is worth a thousand words" so I went to the hanger and took some for you today. Click here http://picasaweb.google.com.au/airtr...eat=directlink
Pic #11 shows you what I mean about the gov. pad. There's also some pics of the "bumps" and a shot of the underside cowl showing the mods to the inlet ramps to make it all work .

I hope this stuff helps you out. Its just the way I did it,I'm sure there is others in here that may have done it differently but no ones talking!!

Keep us informed on your progress and feel free to ask more questions. Don't forget to post a few pics of the finished product!

Cheers & Beers
Graham

Lionclaw · #5 11-14-2009, 04:30 PM

Thanks Graham! Those pictures are great. I had completely forgotten about the top cowl when I was making that piece. I'll be doing that center piece tomorrow, and it looks like I'll be going in front.

airtractor8 · #6 11-16-2009, 07:37 AM

Hey Andy, I have a question for you. I notice that your cylinders have a green painted stripe between the pushrod tubes indicating that they have been bored to .010" oversize. Were you able to purchase 9:1 compression pistons in .010" oversize for the H2AD or did you have to go with .010 over in 8.5:1 pistons common to many of other 0320's? I know that at one point Superior were making .010 pistons for the H2AD but no one knows about that over here. I haven't been able to find them anywhere, all I hear is "never heard of them"!! Can you tell me if they are still available and where did you buy them from? Also what approximate cost did your cylinder overhaul run to with piston,valves and boring etc.?

Regards
Graham

Lionclaw · #7 12-07-2009, 07:36 PM

Sorry I missed your last post Graham. I'm working on routing fuel/oil lines and I came back to look at your photos.

I took my cylinders to a local shop and had them overhauled. OH total was $2k. Tag shows parts replaced were valve keys, exhaust guide, ring set, exhaust valve, and piston for each.

The tag doesn't have the part number for the pistons. I'll have to take a look inside and see what they are. I do remember the guy had some trouble getting the pistons. The first ones his supplier got him were wrong, and it took him a few extra weeks to get everything sorted.

Lionclaw · #8 12-08-2009, 03:39 PM

I bought my engine for $2300 on ebay, and I got lucky that it was in such great shape. It was at 2100hrs, no prop strike, and logs included.

I have about $8k in the engine right now including accessories. All parts were sent out for OH. Crankcase, crank, cam, rods, gears, cylinders. Everything came back yellow tagged, new limits on crank. I got an overhauled carb, mags, and fuel pump from ACS.

If my time didn't cost anything (I don't usually factor it in so long as I'm learning something) this would seem like a great way to go for someone like me, who doesn't have a huge pile of money to play with. If money was plentiful I would probably go with the new Lyc from vans or a clone engine from a reputable builder.

I'm a bit too timid for prop-strike engines, so if it's the $7k mid-time prop strike engine I would probably stay away.

jfogarty · #9 12-09-2009, 02:57 PM

Andy, Thanks for the advise, I appreciate you sharing your story on the engine. I was looking at the one with the prop-strike, however, there are a number of that model on Barnstormer. I don't have the money right now to purchase the engine, but it is time to order my finish kit, so I need to have a plan. Thanks for your help.

Jim

Lionclaw · #10 12-09-2009, 06:14 PM

No problem. If you want to leave the option for an H2AD engine open, be sure to specify the H2AD engine mount when you order your finish kit. I believe it will fit any other dynafocal I engine, the only difference being the bar across the top is curved to allow room for the H2AD crankcase.