Just picked up a new plane with a preinstalled NEW Magnum .52 glow.

Owner claimed the engine had not been run or the plane been flown (Phoenix funstar)
I finished the build of the plane, installed the fuel tank and set out to the front yard for some engine break in. I installed an OS #8 glow plug, fueled up, applied the glow plug starter and electric starter, the motor will not spin. Acts like a hydro lock. Removed the glow plug no fuel in the engine. Re applied the glow plug. Acts like a hydro lock, will not spin. Removed the glow plug and it spins just fine.

I had a burned out Evolution plug from my Alpha 40 trainer, just for kicks, I dropped it in the engine, the engine spins free. Put the OS plug back in, it acts like a hydro lock when I apply the starter.

I am new to the hobby, flow an alpha 40, built a phoenix dolphin with an OS .55 never an issue. New to Magnums. Is there a recommended plug to use. The website for the magnum engine says a hot glow plug.

Every Magnum I have had is VERY tight at top dead center when new. Read the manual, follow the break in instructions and you will end up with a good running motor.

Try pre heating the engine with a heat gun or hair dryer.

I use the Thunder Bolts from Hobby People or Enya #3.

Is this a .52 two stroke or the .52 four stroke? The 2s has a finiky mid range. Takes a while to get it tuned but the engine has tons of power.

Buzz.

2 Stroke. I'll try the heat gun tomorrow. But I can't even get it started to start the break in process.

As BB indicated above what you are experiencing the the cylinder choke a a typical ABC, ABN engine tighter bore at top dead center. The thing about one brand of plug allowing free spinning is just confusion about how you applied the starter.

Avoid dry cranking at all cost especially on a new engine. For your first start on a new engine with considerable choke do not hand prop and use only a starter being careful to back the prop up aginst compression before applying the starter switch. Now my preference for an engine with considerable choke is to remove the plug and hold a finger over the exhaust outlet with the throttle wide open then spin the engine for a few seconds or until fuel spits out the glow plug hole. Then reinstall the plug and go for the start. heating the engine can help however I have not saw one yet that absolutely required it. Some high performance racing engine yes. Make sure your starter battery chord is not excessively long and that your battery is properly charged.

The OS #8 plug is a midrange plug I would suggest in the case of OS plugs either #3 or #6, The six is the new replacement for the three.

John

Hi!
Did you have fuel inside the engine when you applied the electric starter? -It sure sounds that way! An engine which is dry inside is no problem to spin with the starter, providing you have a good 12V (7-10A) motor cycle battery (dry-lead) or...using a more modern14,8V LIpo ocr LiPoFe battery.
OS 8 or Enya 3 are both good glow plugs to use.

Our LHS had a shipment of the 52s a while back that had such a tight fit they wouldn't turn even when the cylinder was heated. We took the first one back and were given a different engine and it was the same way. Went back to the LHS and put a prop on a couple more until we found one that would turn by hand. They really do have a tight fit but the heat gun usually takes care of the problem. These wouldn't roll over even with the plug out.

You have to make sure the prop is as far off top dead center so that when you do apply the starter, it has a chance to get spinning. This is true of even broken in engines. I enjoy starting a new engine. When new, they're tight. But after you get them started a few times, they loosen up just nice. They start easier.

I have started many engines. This is just my first experience with Magnum engines. I have applied the starter as I would with the easy to start OS motors I have. I will be going to the LHS to pick up a few different plugs to try tomorrow. The evolution plugs have no problem spinning the motor but the only evolution plug I have is burned out.

I find Magnum engines easy to start. Even when new.

Manufacturers recommended glow plug, a hot heat-range glow plug designed for performance 2-stroke engines, such as Thunderbolt #3

http://www.hobbypeople.net/media/upl...structions.pdf

I have quite a few Magnum engines and the 52 is one of my favorites, at this time
I have 3 of them, the last was extremely tight when I received it and like you had
a heck of a time getting it to spin over with the plug seated. The procedure I used
to disconnect the fuel line and inject some after run oil into the cylinder without the
plug in place and spin it over for periods of 15-20 seconds at a time, maybe 4 to 5
times then reconnect the fuel line, prime the engine by placing finger over the carb
and then reinstalling the glow plug but do not seat it, leaving it a couple threads up
from seating the copper washer, this has the effect of reducing the compression in
the combustion chamber and should make it easier to turn the engine over while trying
to start it, an old model boat engine trick with tight ABC engines, once the engine starts
tighten the glow plug quickly and the engine should continue to run. Keep it a little rich
but not slobbering rich, as that can damage to the con rod. Run at least 3 full tanks of
fuel through the engine before going airborne and on the first few flights don't throttle down
too far out as the engine "will die" until it is totally broken in. Magnum engines are great
engines for the money and you will be rewarded with long engine life if taken care of.

BTW I normally use the OS #6 plug on all of my glow engines with 15% fuel.

Bill D.

If the engine won't turn over due to being brand new and having a very tight pinch at the top of the cylinder sleeve, it shouldn't matter which glow plug you have installed. I suppose a shorter plug might lower the overall compression level in the combustion chamber just enough to make a difference when trying to turn the engine over, but I wouldn't have thought so.

I find the Fox RC Long glow plug with idle bar normally works well with most of my 2-stroke engines; the idle bar isn't necessary, but it doesn't hurt anything either. It's a medium hot plug like the O.S. No. 8, and works well in many different brands of glow engines.

I've owned one Magnum .52 XLS 2-stroke. It was a very powerful engine, and it still had a tight pinch after a couple of hundred flights. My .52 XLS seemed to like to run well only at wide-open throttle, and I'm told this is typical of the model. I seem to recall that my .52 XLS came with a remote needle valve assembly that sucked almost as much air as it did fuel. I scrapped my remote needle assembly and moved my high speed needle up to the carburetor body to assure reliable operation.

If you can get your engine fired up and you can put one or two tanks through it, I suspect it should loosen up enough to start easily enough after that. Good luck!

The OP is saying that his engine will spin with an old Evolution plug but not with an OS plug. Only causes I can think of are:

-The Evolution plug has lost its seal and there is no compression with the Evolution plug.

-The OS plug is too long and is interfering with with the piston. I don't think the various 2-stroke OS plugs would do this buy maybe an OS-F plug might?

Right from the manual:


Glow Plug Recommendation
Glow plugs can make a big difference in the performance of your engine.
We recommend using a long-reach, hot heat-range glow plug intended
specifically for high-performance two-stroke engines. Do not use a cold
heat-range plug and do not use glow plugs that use an idle bar. This can lead
to erratic engine runs, difficult tuning and eventual engine wear and failure

Glow Plug:
Thunderbolt # 3 Glow Plug (Product Number 115559)
The Thunderbolt # 3 glow plug is designed to be used in high-performance
engines using fuels containing 10%~30% nitro content and in any
environment. It is a ‘hot’ type of glow plug for easy starting, excellent
transition and incredible top end. The glow plug is also very durable and

I talked to a few people at our club field and will be bringing it out today. Because this was a "USED" purchased engine, one of the guys wants to check it out. I don't know enough to open and check seals and what not. I did order a thunderbolt plug and had the same issue. Will not turn over, or very hard to. Some of the club guys are also going to look at my starter, thinking it may not be spinning right. Thanks for the all recommendations. Ill post a resolution once found for anyone else that may be having these issues too.

That's the best idea yet! I'm interested in the final results and answer.

So I take it to the field, Pull the plane out of the truck, loaded up with some fuel. Talk to one of the guys about the problem I had trying to start it at home. I say watch this. I apply the glow igniter and apply the spinner. Motor spins over and starts up. *** 4 guys staring at me like whats the problem. kill the motor and check over all the lines. Starts back up like no issue was ever there. Ran three tanks through it for break in. Must have wanted to just go for a ride in the truck.

Will maiden the plane this Saturday.

In my world we call that P.F.M. pure freakin magic

Could have been a simple vapor lock, to much prime, low starter battery or the airplane Gods just wanted to mess with you


Buzz.

Ill go with all of the above since I tried it over a weeks time at home and got nowhere with it.

Bet you charged your starter battery before going to the field.