Campgems

I've browsed through the parts listing for the new "blue head" Magnums and I don't see any parts that are different between the two versions other than the rocker cover. I'm about ready to start building an ASM P-61 and I originally purchased a pair of Magnum 52 four strokes for it. I've discovered that although they are the recommended engine on the kit, they are a bit under powered. Ihave a pair of Magnum 70 four strokes, one NIB and the other has a couple gallons of fuel through it. I was thinking I would like to start the plane off with matched engines, and another new 70 was in order, but I'm wondering if if the Blue Head has any performance differencefromthe predecessor? Would you go with one blue and one grey head, or one new grey head and one used grey head?

Don

w8ye

My Feedback: (16)

You need to put in an order for a valve cover.

Last year this time, Mike Greenshields at Toledo said that there was no difference except for the valve cover

Campgems

Jim, that is what I was thinking also.

Maybe 3, a couple for the new 52's and one for the 70 and then a new 70.

Don

Kmot

My Feedback: (24)

Just buy a can of Duplicolor engine enamel and do every valve cover in your inventory.

w8ye

My Feedback: (16)

If you bake them in the oven after painting enough to get them up to temperature, the paint should stay on well?

Campgems

If only all our porblems were solved with a can of spray paint.

Don.

NM2K

My Feedback: (14)

The blue anodized valve covers are inexpensive, so I ordered enough of the various sizes to match my inventory of Magnum engines. Now my old Magnums match up perfectly with my new blue head engines.


Ed Cregger

Roary m

My Feedback: (67)

I'll tell you a trick I found out since I am going thru the same process with the same plane. I bought an OS 70 Ultimate and wish I had bought two. True, there are temperament issues with the earlier runs but the engine is identical to the 52 side to side and front to back right up to the thrust washer, a complete drop in. The deck height is a little taller but it turns a 13/7 and really goes. I got word from one of the scale guys down at Sepulveda and he said somebody there had an ASM P 61 with OS 52's and said it ran very well, fast. I don't think the Magnum would be that different than the OS, but heres my two cents. If I can, I will be looking for another one of those 70's.

w8ye

My Feedback: (16)

I used to have a Magnum 61 four stroke and a ASP 61 four stroke. They ran right up there with a Saito 56 and were stronger than my OS 52 engines.

Magnum doesn't sell the 61 any more but ASP does.

Campgems

I'm not sure if the O.S 52 is any stronger than the Mag 52, but the carb is better. Ikilled one of my O.S. 52s but was able to salvage enough of the carb that a new case gave me a fresh O.S 52 carb. Humm. Pull the carb off my other O.S. 52 and put them on my two new Mag 52"s. It would releive me of a lot of the issues I had on my Mag 52. Icould never get a reliable idle on it. Maybe now that I have five more years of experience adjusting four stroke carbs, I could get it to work OK.

Weight is an issue, or potential one. I used a Saito 62 as a bench mark weight and the Mag 70 is going to add about 9.6 oz to the weight, and it's all well forward of the CG. If I remember right, the Mag 70 was about 8 oz heaver than the Mag 52. The width of the case is about 4mm wider also. That would put a full pound up front. I may need to reconsider the 70s.

Jim, I'll look into the ASP61s and see if they are based on tthe 52 or 70 crank case.

Don

Follow up- The ASP 61's are avaiable on Ebay for $150 delivered from China. The engine is the same foot print as the 52 and actually weighs a few grams less than the 52. Sounds like a good choice.

Don

mike109

G'day

The ASP/Magnum 61 FS is the same size as the 52. It is not based on the 70 which is physically much larger. The 61 is quite small and light for its power.

I have had several 52s and a couple of 61s. I currently have one 61. It runs well and swings a 13 x 6 prop in a Great Planes Slow Poke. It does have a down side though, it feels old and loose even though it has had very little running (I bought it from a deceased estate and I have known it since it was new) and its exhaust valve leaks. I have tried my usual "lap with tooth paste" trick but it still leaks slightly.

I have decided to just run it and I am now using some castor with it and I think this is helping. Its compression feels better now and it also sounds less clattery. If the valve starts to leak more, I may buy a head or I might just buy another one or a second hand OS. Or another Saito.

Campgems

Thanks for the info Mike. My mags all seemed a lot low on the conpression end. All ran well though.

How did you make out in the floods? I think I read that Dubbo was in the path of them.

Don

mike109

G'day

Yes, Dubbo was a bit soggy but most if not all the houses in town were above the flood level. The local hobby shop was closed for seven days as they were without power. The flood did not actually get into the shop but the power system has to be turned off to that part of town because some street lights and traffic lights went under water.

One business which operates heavy earth moving machinery is located on the flood plain and they built their own levee surrounding their headquarters with their own machinery. Nothing got wet but they had to dig their way out when the water went down.

Cheers

Mike in Oz

DarZeelon

Quote:

ORIGINAL: Campgems

Follow up- The ASP 61s are avaiable on Ebay for $150 delivered from China. The engine is the same foot print as the 52 and actually weighs a few grams less than the 52. Sounds like a good choice.

Don,


It could be obtained for even less...

If you stay on [link=http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8985]this page[/link] for a few minutes, you'd get a much less dear offer than initially appears.

Don't close the page, because the offer will not reappear.

I believe shipping will not be very expensive, with shipping weight being just a pound (less than half a kg).

asmund

I have two of the ASP .61 fs engines, they weigh as little as 445 grams and are the same outside dimentions as the .52. Great running engines and the link given by Dar is the place I get them the cheapest. I can`t understand why so many buy the .52 when there is a .61 from the same maker, and it is even lighter too.

Campgems

Dar, thanks for the heads up. Ijust ordered a pair and two Fasst Orange 8 ch receivers for just a tad over the price of two engines from the Ebay source.

Now to sell my 52s. Man, this plane is getting expensive.

Don

earlwb

I have played with a couple of the ASP 61 four stroke engines and they both worked quite well, once I figured them out. The ones I ran needed 15% nitro glow fuel before they ran OK. They did not like 5% nitro fuel much at all. They both ran really good with 20% though.
The other issue was the main needle valves acted as though they had false needle settings and I wound up using a short length of extra large fuel tubing to alleviate the issue. After that the engines ran Ok and were easy to adjust.

But I had messed with some other ASP engines of different types and the carbs all worked just fine, I didn't have to help them out to get them to work. So maybe it was a fluke or something.

I just noticed that Hobby City is now stocking some parts for the ASP engines. That is a nice surprise as before you were pretty much out of luck if something broke on you. http://www.hobbyking.com/hobbyking/s...idCategory=422

asmund

All parts for ASP/Magnum has been easily available from Justengines for a long time, but it is nice that Hobbyking also offer spares now

Jimaroc

Hey, guys, just came across this thread. Apparently, ASP/Magnum had some issues with valve springs in some of the ASP/Magnum FS engines and my impression has been the blue valve covers indicate engines produced after the valve spring problem was discovered and rectified? Also, since ASP/Magnum are basically Chinese-made OS clones, when OS changed to blue valve covers on their newer four strokes, Magnum seemed to follow their lead. Rustoleum makes inexpensive (

jeffie8696

Shimming the valves on my original Mag52 made a huge difference but the valve seats were ver poorly made and leaked despite it . The blue head that replaced it works fine.

mike109

G'day

"Shimming the valves?" I am not sure what you mean. I have an ASP 61 FS which runs OK but which does have a leaking exhaust valve. I have tried my usual method of lapping with some tooth paste but to no avail. I think I will eventually just buy a new head complete for it.

Cheers

Mike in Oz

jeffie8696

Shimming the valves means to install a thin metal washer under the valve spring increasing its tension. This is commonly done in automotive engine rebuilds. You must be careful not to make the shim too thick or you can cause a spring to bind.