I would personally like to thank one of the RCU member here on this forum. I was having problems with a Magnum 70 4 stroke. It was sent to hobbypeople to have it fixed. Came back and would not run right. Grey Beard seen my post and pm'ed me to send it to him. I did that and he has fixed the problem. Where else but on RCU would you find someone like Grey Beard that was willing to help (BTW, cost, Shipping) Thanks Grey Beard. Hope I can return the favor some day. I hope the moderators will let this post stay. To show newbies what kind of forum this is.

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"It is another's fault if he be ungrateful, but it is mine if I do not give. To find one thankful man, I will oblige a great many that are not so."
Seneca (5 BC - 65 AD)

I believe there are a number of folks on these forums that are extremely helpful. In just the short time I have been a member I have been amazed at the time members have taken to assist those in need and some of us that don't have much experience gain so much from these forums. Don't forget there are great sellers in the Marketplace as well. Great work Grey Beard and all those that put their time into helping others.

It's nice to know there are still people willing to lend a helping hand in these times. Good job Graybeard!

Well Grey Beard, we tried to keep your secret quiet here on RCU. But Iguess the cat is out of the bag now. Grey Beard is RCU's Guardian Angel!!!!



BTW, big pat on the back for helping out!!!

Ataboy G.B.


Bob

Ok Gene, I'll be sending you a truck-load of engines next week

(That's Gene as in Greybeard, not Gene as in goirish)

Kudos are certainly in order to Gray Beard for his generous act. Not everyone would have stuck his neck out to that extent. Hats off to goirish also for sharing a good feeling story with us. From reading many posts from both in this forum, I believe they are shining examples of the caliber of people found in our hobby.

You two guys can PM me for my address to send your contrubutions.

Ithink he just needed to borrow an engine for a couple days to test fly an airplane.

Oh wait a minute... that's what I would do. Never mind.

It really is good to see people in this hobby willing to help out. Too often we see some people devlelop an elitist mentality and forget that there were times when they needed help or didn't know how to do something yet.

good job Greybeard, nice to know there are still people out there that are willing to go above and beyond

not meaning to take away the well deserved congrats, but after all of goirish's post on this engine, inquring minds want to know what was wrong with it?

I'll let Greybeard answer that. He said that it looked like it was never taken apart.

OK. I'm just curious because I have one of these engines too, so, just in case I have the same problem []

I have several Magnum 4 strokes and never a problem with any of them, until this one. I really don't think this is the engine that I sent in. With all the work that they said they did, 143.00 worth, then to say it doesn't look like it had been opened. I sent it in to have the valve keepers installed on one valve that I lost trying to put it on.

The engine is not fixed, the engine is just running pretty well. Big difference. When I opened it I couldn't find anything wrong with it other then some rust. Quite a bit of rust but it still doesn't answer the question, why no compression?? Today was run in day and Gene's engine fired right up and it only took a few seconds to tune it up, very touchy on the high end but it does have a sweet spot. I never touched the low end. My thinking is the ring is just going to take a lot of time to get it to seat. I ran it in 10 ounce runs with a cool down between each run. There still wasn't any compression either right after shut down or after cool down?? Last thing I did was check to make sure the valves were seating and they were both just fine. Other then ring seating there is no reason for this engine to not have compression but it doesn't?? You can roll it over by hand and there is none of that nice kerthunk when you flip it over. Only prop I had for it was a MAS 12X6 and first run was around 9500 max and the last run was just a taste over 10 grand. I didn't fool with the low end but it would go down to 2500 and putt along then I could crack it open without any stumbling at all. It would go lower but I took no readings lower then that. I think it just needs some air time to get the ring to seat.
I sent one of my OS 1.20s to an RCU friend and got it back from him yesterday so I test ran that too. I didn't do anything at all for Gene that anyone else could have done but this fellow, I won't mention Dons name though, not only made me a complete new pump of his own design but then took apart my old pump and designed and made a new diaphragm for it. This was in answer to the way OS/GP makes things so we can't rebuild them ourselves. It was leaking fuel and flooding too, not just a little, but I had gotten a bad set of bearings when I rebuilt it from BOCA. I said the bearings were the wrong size but Boca stated these were the correct size, bearings should not just slip into the case!! But according to Boca these were they way they should be. Anyway, Don installed new bearings and fixed the unfixable pump and that old dog is running like new and not leaking the fuel out the front bearing. A perfect job by another RCU member.
Don is going to or has already posted up a how to on rebuilding these closed and sealed pumps here on RCU for the rest of you. He was just waiting to see how I felt about his rebuild, NICE!!
I thank you Gene but I still can't figure out why it doesn't have the compression but it is running well.
Other Gene

You are a good guy, Gene, no doubt about it.

CGr.

Thanks CG, You did mean me, right

Both of you, of course, my friend!!!

So it just feel like low compression when turning by hand? It must have enough compression at higher speed otherwise it wouldn't run. I bet you are right, the ring is just taking a long time to fully seat.

I have a YS 1.40 that belongs to another club member. I promised him I would seal it up with new gaskets and O-rings. Maybe I can just send it to you?<br type="_moz" />

I've got a Saito 91 that sometimes for a week or two between runs will have low to no compression. And yet once it runs then shut down has full compression. I probably have a sticky valve but what I'd ask regarding the Magnum is how is the compression right after you shut it down? Nice compression? Still none?

A friend of mine once had a 2 stroke that lost compression between running, which we assume is a sticky ring which I find to be slightly incredible, but evidently possible.

Reading your post again Gray Beard if the valves are OK perhaps, however unlikely, it's the ring.

I'm sure that Graybeard said no compression after shut down or when it cooled.

Thanks goirish - I went back to clarify what he'd written then edited my post. If it's not the valves the compression is being lost in the cylinder - ring/cylinder.

And I'll state for the record here that Gray Beard has written a lot of information that's been important to me.

Thanks Gray Beard!

I get this low compression once in a while from a four stroke? There are no ports in the sleeve but I have been told that the ring rotates and if it is in the right/wrong spot you will have low compression. It comes back after running. The two strokes have a pin or slot to keep the ring from rotating so they shouldn't have the problem. As mentioned, if the engine runs this well and I can get up to the working RPM range with that prop then there must be enough compression while the engine is running. I felt no gain in compression weather the engine was hot or cold. One of the first things I did was shoot some oil in the combustion chamber to see if that made any difference, nope! I do think I will end up getting a compression gauge for glow engines, I have them for my gassers but I never use them very often. Still, A new toy!! I'm sure this engine is just fine and will get better with age and use. It was pulling my cinder block around on the concrete with 50 pounds of lead on the block so I know it has that tug factor!!

Goes to prove the old saying:

"If you have enough power, you can make a brick fly." I just didn't realize Gene was trying to prove it true!

Thank you for your help Gene.

Brian

Brian, I never thought of that but watch for that photo when I just can't help myself and need to post a smart ass answer!!!! I did finally have to put the block,{{My run in stand}} in the gravel to keep it in place. Every time I let go that block was heading there anyway. Right after that I mounted up my 1.20 for a test run, sweet!! Don did a heck of a job for me. I was so mad by the time I sent it to him it was going to get trashed!![:@] Just one thing after another and I was sick of fooling with it. Don calmed me down and had me send it to him, see, we all need help sometime. I can get the idle down to 1200 and then crack it on without a burp. Now to get in back into a plane and get the plane set up for tomorrow.

A man who can't remember what day it is and you let him fix your engine? [X(]

Sorry GB, I just read one of your other posts.


It's what I call "Paying it forward". Helping out those in need with what you were taught/given.

GB is a great example, as are many others here.