Ralph White

Hello, I am starting this thread in hopes of solving a problem I have been having with my OPS 60 FIRE Redhead engine that I have been flying in a Saturn classic pattern plane. I've had this Saturn and engine since I flew it in Pattern in the late 70's. The Saturn was designed by several times Canadian National Champion Ivan Kristensen. I don't remember having the engine problem in the 70's but that was a long time ago.

The engine problem is that it goes lean in vertical uplines (Top Hat, etc). In my next post I will list the details on the engine/plane and list all the things I have tried to do to solve the problem of going lean.

Here are a couple of pictures of the Saturn and of my son, Nick, and I flying it at the Chicago Fox Valley Classic Pattern contest the last 2 years.

impactiq

My Feedback: (57)

The one thing that comes to mind that has happened to me after all the obvious has been looked at and/or replaced...... is the high speed needle seal. Exact same symptoms you are describing. It never leaked fuel but was just "loose" enough to cause a problem only in vertical maneuvers. Level flight and mild angle climbs up to 45 degrees... no problems.

I am assuming this problem your are having is does not change regardless of the amount fuel is in your tank.

Ralph White

Thanks for the response impactiq. I have checked the needle valve for air leaks. I put in new o-rings on the needle. It seemed to help a little but was still going lean on the up-lines.

Before I list everything I have tried to get my OPS 60 FIRE Redhead to stop going lean in up-lines I thought I would talk about my latest development.

I have connected with a new friend from Deatsville AL, Jim Oliver. He is a Classic Pattern Flyer and owns serveral classic pattern engines including 4 OPS engines (2 Redheads and 2 Goldheads). I explained the problem I have been having with my OPS. He offered to loan me one of his Redhead carbs to try in my engine. I very much appreciated and accepted his offer. If my engine runs correctly with Jim's carb it will indicate that my carb is the problem.

I removed my carb today to mount Jim's carb. While I had both carbs out I decided to compare them to see if there was any differences or obvious problems with mine. To my surprise the carbs are not identical even though they are both for the OPS 60 FIRE Redhead. Most of the differences will not affect the performance of the engine. However, there are a couple differences that may affect the performance. I'll list the differences starting with the ones that may affect performance.

1. Direction of spray bar notch. My is the one with the notch straight down. Attachment 1 & 2.

2. Diameter of fuel inlet fitting hole. Mine is just slightly smaller. Can't tell by looking at it but a small drill bit will go in Jim's and not in mine.

3. Taper of throat in bottom of carb. Mine appears to be opened up more. It can be seen in Attachment #1.

4. The angle of the fuel inlets are different. Probably would not affect performance. Attachment #3

5. Notice that the control bellcrank pivots at a different location and the boss for the pivot mount is larger. Attachment #3.

6. Bellcrank screw hole goes through on my carb body but not on Jim's. Attachment #4.

7. Metal needle valve body on Jim's, Plastic body on mine.


I plan to get Jim's carb in tomorrow and will be flying the Saturn as soon as the weather permits. It's winter here.

Thank you very much Jim for letting me borrow your carb to make this test. I'll let you know any results ASAP.

Ralph White

Roguedog

Any idea what the throttle bore is? Most 60 size motors will have trouble with anything larger than 9mm without a pump.

If yours has the spray bar opening at the bottom of the carb I'd say that would be the correct postion. IMO I would say the replacementcarbs spraybar is misaligned and should also have the opening at the bottom as that would be the best position for max fuel draw.

I'm also thinking that there's a partial blockage of some sort between the fuel inlet of the carb and spraybar. I once had a carb that had a small blockage in that area that was doing the same thing. Took off the needle and seat and a piece of gummed up fuel was blocking the passage partially.

I just got my first plane going since I got back into the hobby and decided to usepumps this time around and Iam sold on the concept as the engine on my Utter Chaoshas positive pressure to the carb through all manuvers. I got about 40 flights with no dead stickswith the same glow plug. The one deadstick I did get was due to a small piece of aluminumI must of picked up of the runway as it lodged in the glow plug.
I completely broke down the engine and no aluminumin it was broke or chipped os must of came from the runway.

Regards.

Jim Oliver

My Feedback: (1)

Ralph,

Can't remember if I told you, the carb I sent to you came with the Redhead when I got the engine from someone on RCG, so I can't be "certain" if it was original to the engine.

The differences are interesting; it appears that yours has in flight mix control.

I suspect that the spraybar with the slot "on the side" is correct. The air moving through the venturi would shear off the fuel flow and possibably atomize better than with the slot on the bottom of the spraybar.

Jim

impactiq

My Feedback: (57)

Ralph, Here is a picture of the OPS 60 red head with the carb open. It shows that the notch is visible like the one Jim sent you.


Mark

doxilia

My Feedback: (3)

Fellas,

Thought I'd join the fold since I just bought one of these puppies. Only problem I anticipate at the moment is that it comes with a marine flywheel instead of a prop drive washer. Does anyone have a spare one they would be willing to part with?

I can't recall off the top of my head but how are the red and gold head versions different? The one I picked up is a red head. Could it be the reds are 60's and the golds are 61's?

David

Jim Oliver

My Feedback: (1)

As I understand it, the Redhead was an earlier engine than the Goldhead; my Goldheads and Redheads are all marked ".60".
The Goldhead is a 5 port engine, I think the Redhead is a 3 port engine but it has been a while since I looked at mine.

Flying Models has a detailed review of the FIRE Goldhead in the Dec. 1984 issue. I have seen NO such info on the Redhead, but would like to.

Jim

doxilia

My Feedback: (3)

Thanks for the info Jim. That makes sense. Have you compared the two running on the same setup?

Know where I can pick up a drive washer?

David

Jim Oliver

My Feedback: (1)

David,

Bob Oge is making up an order for OPS parts right now; I need a crankshaft for my basketcase Redhead. I will PM his E mail to you.

Jim

Ralph White

Was able to finally get my Saturn to the flying field today. 37 degrees, 5 MPH wind down the runway and sunny. It was nice.

As I mentioned earlier, the only thing I changed on my setup was replacing my carb with Jim Oliver's. Everything else was exactly the same. Fired the OPS up and adjusted the highspeed needle. Well, to my surprise, the engine ran exactly as it did with my carb on it. Full throttle was uneven and as soon as my son held the nose straight up the engine went lean and died if held up long enough.

The next thing I did was open the low needle up 1/4 turn. Seemed like it helped but engine still went to lean. Opened the low needle another 1/4 turn and it helped a little more but still going lean. Wasn't even good enough to try flying.

Out of discus, I tacked the engine. It was turning 12900 rpm. I had a 11 x 7 1/2 Zinger prop on the OPS. I decided to try one of my Handcrafted Props by Max Dailey that I use to fly the Saturn with back in the 70's. It is a sweep tipped blade, thin, 11 x 7 1/2-7 pitch. WHAT A DIFFERENCE. Without changing the needles the OPS turned this prop 13900 rpm. My son held the Saturn's nose straight up and the engine did not go lean.

I had said I would never fly any of my Max Dailey props because they are not replaceable and collectables as far as I'm concerned. Well, when I heard the engine running perfectly, I could not resist flying it. I could tell on takeoff that this prop was going to make a big difference in the flight performance. Once I got altitude and trimmed a little I tried a few loops and top hats. The engine was a shade rich but not bad. The engine pulled through the loops and top hats with no problem. I then did a couple straight uplines for a considerable distance. It leaned just a fraction but was what I consider normal without a pump.

I remember someone telling me the 11 x 7 1/2 was to big for the OPS Redhead, but I didn't believe him. I think that he is right now. What I think is happening is the bigger prop is lowering the rpm enough that the tuned pipe is to short for the slower rpm when the plane goes vertical and it comes off the pipe or causes the engine to go lean.

My next thing to try is an APC 11 x 7 prop. It appears to be about the same or less blade area as the Handcrafted prop. This is the prop that most of the CPA flyers in this area are using. Although it weighs 1.4 oz as compared to the Handcrafted prop at .5 oz.

After trying the APC prop I am then going to try my carb instead of Jim's. Mine has an in flight adjustable needle which will let me fine tune the card without landing.

I can't believe that I have messed with the OPS for so long without trying a different prop. I sure hope that the wrong prop is all that was causing my problems.

I'll let everyone know how it goes the next time out.

Ralph White

Ralph White

Roguedog, I was beginning to think that I might have to go to a pump for by OPS. Maybe I won't have to now, but was wondering what pump you are using on your engines. Are you using the carb that came with the engine with the pump?

Thanks,
Ralph White

Ralph White

The following is a PM sent to me by Cees Wester from the Netherlands. I posted it here as it contains some helpful info. Thanks Cees, Ralph

" Hello Raph,

Just as me, you are "Old School", so, maybe you already know this and checked it in detail.

Tankpressure isn't constant but related to the power level of the motor on any moment, read RPM.
This way the tankpressure has to be equal to the inside header pressure near the connection.
Equalisation is easy in the beginning of the fllght because the amount of air in the tank is stll low. After some while there is a bigger equalisation airflow needed throught the line between header and tank. Throttling back, from tank to header, throttlihg up from header to tank.
For this reason it is important the bore of the header connection (tap) for the tank is still full bore, not blocked. In other words, the bore cannot be biig enough!.

There can be a small chance the tank pressure isn't yet on right value on moment you pull up the plane in vertical.

So the question is, and maybe you already asked yourself, "Is the bore of the tankconnection still full bore Ralph? "

Taurus Flyer



I write you this PM because I am under moderator status for a long time and posts of me must have been checked by a moderator before publicing.
Result is, it can take weeks, or they never show up, and that won't help you.

If you find this post valuable you may copy it in your thread if you want.

Merry Christmas to you and your son, and Happy Landings!

Cees Wester
The Netherlands "

Dean Pappas

Hello Ralph,
As I read your original post, I thought, " sounds like an overly short pipe." Your small prop experiment bears this out. Lengthen it 1/2 maybe 3/4 of an inch.
Also, your pipe pressure tap location in the header is less than optimal: you' would benefit from putting the tap at the high point of the pipe.
Regards,
Dean Pappas

Ralph White

Thanks Dean, I'll try both of your suggestions as soon as weather permits.
Ralph

Roguedog

Ralph,

I'm using a Perry VP-30 (blue case) pump with a Tee fitting(see pic) right at the carb. The carb is the standard OS 5B carb designed for the OS Max 50 FSR, nothing special.

Since this is a vintage engine I decided not to try and run it with just muffler pressure as I didn't want to have to worry about a lean run at least from relying on the vacuum from the engine. I also add 4oz of castor to the glow fuel I'm using and also run it as rich as I can.

I'm not using the check valve on the tank vent and it is vented to the air, no muffler pressure.

I have positive fuel pressure to the carb during all manuvers and only had one deadstick so far due to a small piece of what appeared to be aluminum that got wedged in the glow plug. over 50 flights on the Utter Chaos now and it's turning 14400 rich, very nice vapor trail behind the plane while flying.

Ralph White

Thanks for the reply Rouedog.
Ralph

Ralph White

Discovered I have a leak in the fuel tank. The seam split about 1/4" right behind the stopper. I'm sure the split did not help the tune pipe pressure any. Will order a new Hayes Slimline 16oz tank next week. By the way, the old tank was 35 years old.

Later,
Ralph

Ralph White

Hi everybody,

The weather has been bad for flying here in Illinois. I ordered a new tank and other goodies form Tower Hobbies. They are in now so I will be getting the tank installed in order to do some testing again. I also plan to install a pressure tap on the tuned pipe at the high point of the pipe. Using a larger i.d. fitting size also. I will leave the old fitting in the pipe so I can see if there is a noticeable difference in the fitting locations.

I'm going to first run the OPS with the Handcrafted 10 3/4" x 7 3/4"-7" prop. Then I plan to try the APC 11" x 7" prop to determine RPM differences. May fly with both props to determine any performance differences. If the engine runs correctly (does not lean on verticals) I plan to put my carb back on to see if there is any differences. This will also let me adjust the mixture without landing.

I have the pipe setup so I can change the length. Plan to start out at 17" from glow plug to high point of pipe and then start shorting it to see what happens. Another classic pattern flyer in my area, Bill Drake, told me 17" is the length pipe he used with his OPS.

I plan to try all of these items one at a time so I can tell which item causes any changes in the engine performance.

Hopefully the weather will let me do the testing soon.

Ralph

dphill2

My Feedback: (1)

Ralph, I can't believe it has taken you two years to find that leak in your fuel tank !! What about your retrack problem ?? did you ever get to the bottom of that ??
Anyway its good to see you are still working on it !!
Lil Dave told me to tell you and Nick, Hello and hope you two can fly some patten with us this year ....
Dave P....

Ralph White

Hi Dave, I don't think the tank was leaking all this time or if it was it was a very small leak. It just started dripping out of the nose wheel area the last time I flew it. If it was leaking before that could have been part of the problem with leaning out in vertical lines.

If you remember, Robart had replaced the air up/spring down retract cylinders with air up/air down cylinders. They only charged me about $15.00 to send the cylinders to me and I put them in the retract units myself. They worked just like Rhom Airs. Problem is they started leaking after only about 10 flights. At that point I decided to can the Robart's and ordered a set of Spring Air Retracts. Took a few weeks to get them but they are working perfect. I don't know why I had so much trouble with the Robarts. Our field is very smooth grass.

As I posted above when I put the Max Dailey Handcrafted 10 3/4 x 7 1/2-7 prop on my OPS the engine came to life. Very little leaning out in verticals even with the hole in the tank. I only have 3 of the Handcrafted props and I don't want to fly them as I consider them collector items since I was a personal friend of Max Dailey. I'm going to try an APC 11 x 7 composite prop in hopes that it works as well as the Handcrafted. I discovered I have a friend who has several of Max Dailey's props but I'm not sure what size and pitch they are. He indicated I could have some so we will see.

Tell Jim Oliver HELLO for me. I sure do appreciate him loaning me the OPS carb for testing. I should be done with it soon. I'm about ready to put my carb back on the OPS to see if it runs the same as his after all the changes I am making.

I am going to try to get down to one of the contest in your area this summer. Will probably be the Huntsville contest since I have a sister-in-law living in Madison.

Ralph

Roguedog

Hey Ralph,

I recently gotanother OS 61 SFN engine off the bay (auction site). I completely go through the engines from there just ot be sure they're ok. This particular one had a badly gunked up piston pin.

The reason I bring this up was this also could have been your problem as well. In my case it was justdryed up castor. I had to heat up the engine with my heat gun to get the conrod to move enough to get it off the crankpin. I tried soaking in fuel but was taking to long.

In your case, if that was part of the problem,running the engine maybe loosened it up. On mine it looks like the previous owner left copious amouts of fuel in the crankcase.

Bryan

Ralph White

Thanks Roguedog, I'll check that out if I decide to take the engine apart. What are you using on the Kobra for connecting the tune pipe to the header? I see it in the picture on your profile page. I need a long one like that also.
Ralph

Roguedog

Hey Ralph, don't laugh, but that's 5/8 water heater hose for cars. I was two years out of high school when I had that plane. Didn't have much money then, still don't for that matter, but I made do with what was available.

I also use hose clamps to hold it on.

Bryan

doxilia

My Feedback: (3)

Ralph,

I hope you don't me posting this here but I thought I might get some good suggestions from yourself, Jim and others on how to proceed.

Below are some pics of the OPS 60 RH I picked up recently. As Jim mentioned, these are the three port red heads. It came with a Perry carb (of equivalent vintage) which was a little wonky. I took the engine apart to check on its internals and it looks to be in excellent shape - hardly run if at all. I happened to have a Picco carb that fit just fine and judging from the OPS carbs, the Picco and OPS are very similar which makes sense considering the "P" in OPS refers to Mr. Picco. I'm thinking that a Perry pump and carb combo might be the way to go in the absence of the Picco carb. Perhaps a little better power output.

As can be seen though it came with the attached flywheel and lacking the proper tools, I was unable to remove it. All the bolts were pretty much seized up but I was able to work them out eventually. The flywheel requires a special caliper to grasp on to it so that it can be locked in place while the front end is unscrewed - I believe. Anyone with boating experience know how to go about this with regular tools?

I assume that I'll also need some parts for the front end - a drive washer as well as a prop washer and retainer nut - well, the nut will probably be replaced with a spinner retainer nut. Otherwise, I assume that the crankshaft front end is standard with threads under the flywheel that can't be seen.

Ralph, I'll be interested to know what performance you get out of your red head with the APC 11x7. Mine is a SE rather than the RE so performance might be a little lower. Anyone know what the required header is for this SE? Is there an engine with equivalent bolt spacing on the exhaust?

David.