I notice on Carlson Engine Imports website that they offer "Aurora" diesel engines from Calcutta, India. There is a .40 cu. in. (6.5 cc) engine fitted with ball bearings. Does anyone here have any experience with Aurora engines? If so, did they perform well?

John G.

John,

I've seen that listing for quite a while, but haven't heard of anyone with experience of the .40.

Their other engines seem to be "inspired" by PAW's layout, and I have seen comment somewhere, here, perhaps, that they are modest in power, serviceable but a bit heavier than the comparable PAW engines, if I recall. The photos of the .15 and .19 Auroras I seem to remember on Carlson's site confirm the similar appearance to PAW engines. Ed's catalog pages used to have a grid with some of the specs and performance 'stats.' Some of those may have been a bit optimistic, for some of the engines.

If the data grid is still there for the .40, I'd be most interested in its weight, first, and then the stated RPM range and power numbers... Engines designed as diesels need to be more sturdy than glow engines, so weight can easily get excessive at a larger displacement. Diesels also vibrate a bit... A larger diesel may shake more and a bit harder. PAW .29s and .35s aren't too bad, at the right settings and loads, but that may not indicate anything about any other "larger" diesel.

Parts replacement is always a consideration, but generally, diesels seldom break anything in reasonable use. Aurora engines, unless they say otherwise, are most likely iron piston in steel - or, at least iron - sleeve, so there should be adequate oil% in the fuel, and all or most as castor. Sleeves and pistons can wear out, but it usually takes a long time, in reasonable use, with good oily fuel. I doubt you'd find a replacement set, but if things go right, you'll probably be tired of looking at an engine "that old" by the time it happens.

I'm almost certain that things you might mislay, like the prop nut and washer - possibly also the head hold-down bolts - will be some kind of standard international thread - IOW available just in case. Spraybars and needles can be swapped in from any source so long as they fit, and the jet hole(s) can be about centered across the intake throat.

If the price looks good to you, and you have a project for an engine that should swing a 12-6 or so prop around 9,000 RPM, an Aurora 6.5 might be an interesting, and not disappointing experience. So, best of luck, either way.

I have had one and was not impressed. I've had other Aurora engines and thought them OK, but nothing special. PAW will cost more, work well, and has parts and service available.

Thank you for the responses..  This is helpful.    John

Copy from Ron Chernich Model Engineering and Model IC Engine Projects:
Aurora was owned and run by Calcutta businessman, Mr Suresh Kumar. He had acquired the Mills .75 and 1.3 rights, along with those for the Taplin Twin and Allen Mercury range. I don't believe any of the latter were produced by Aurora, but the Mills and Taplin certainly were, along with the rather unattractive Aurora K-Series FRV diesel. The latter became renown for breaking shafts too. All in all, a worthwhile and earnest enterprise by a man with a genuine affection for the engines, let down by poor quality control.

How would you like Indian crafts like this: http://www.modelenginenews.org/resto...ages/cmr_2.jpg

Hi John

For further information on this engine, please conduct a search of this forum for information on "Aurora". There have been a few threads over the years. I started a thread based on my experience of dissassembly of a NIB Aurora K-600 I acquired from Mr Carlson.

I did not finish re-building the engine, as life events overtook me, and I ultimately lost many of parts for it which in my absence I left soaking in a petrol ( for US - gasoline) bath. I retrieved only a few parts.

I have since acquired another example, as I believe that despite some very rough internal finishing, they could be (with a little fettling) a fine running engine.

I have agreed to send it to Gregory Kamysz (apologies to you Greg if I have mis-spelt your surname) for his opinion and any remedial work that may be required.

My recollection - appalling domestic made open ball races, the roughest con rod I have ever seen (coarse filed) that had far too much clearance on the little end. There was also a problem with the split collet prop driver.

Other than that, it seemed a well designed unit, with a nice smooth twin needle carb (unlike the crude PAW efforts). However, it is not a buy-and-fly proposition. Read my work notes on it, I was rather loquacious!

The new example sits neglected in a drawer at my work office. I must overcome my slothfulness and get about sending it to Greg.

The engines referred to in an earlier post are Sharma's, which are copies of PAW's. The K-600 is an original (and to my mind rather nice, if traditional peripheral ported) design.

Cheers

Here is a thread on the K600:
http://www.rcuniverse.com/forum/m_7309848/tm.htm

I read your offerings re: the Aurora 600. I enjoyed all of it. I could just see myself trying to do some of those operations such as removing the screw-on backfrom any of these diesels. Thanks for all the information. Much of it applies to the processes of working with any engine, diesel or glow.

John

After reading all of this it makes me realise exactly why I don't mind paying extra for a PAW.

But if you really want to tinker then by all means, but its a rough finished Indian engine.

But what happens when a critical part (like the little end) is poorly machined? All the tinkering is for nought.

The extra weight compared to a PAW would seem to come from the integral cylinder fins and since I have never had a heat transfer problem withseparatealloy ones, I will besticking to the original.

Thanks and good report on an emerging product.

Hi Lou, are you sure you aren't referring to "Sharma" engines? They look exactly like
PAW clones. Aurora engines do not look like PAWs to me. I've got a Sharma .19 and it
handles ands runs beautifully . It is just as strong as the bushing PAW .19. here's a Sharma .15...

http://carlsonengineimports.net/cgi-...LE=SP.15&BODY=

Sharma engine quality is far and away better than Aurora construction and materials
quality. [8D]

Tony G

Just so everyone knows I will pass on getting an Aurora engine.  I wish Sharma made bigger engines. 

              John</p>

You can get a Davis Diesel Development conversion head for most any glow engine.
The larger engines with a smaller bore carb work the best for diesel conversions. But folks have been putting the heads on just about anything with success. One thing is if the engine has a large bore casrb, you can't run really large props as the engine can't draw fuel well with a big bore venturi in the carb. But you can run smaller props really good though.

Earlwb:
Would you name a couple of the engines you like with the small bore carbs and that make good conversions with a Davis Diesel head on them? I'm interested in.40 - .60 engines. John G.

J L G -ANY SUPER TIGRE- 40-51 or OS 40-46LA which ever you can get the best deal on

I have the OS46AX and ST40 both great OS46AX is more $$, the 46LA as as diesel great from review in fly rc mag last summer no is not BB but makes no difference,
the LAs are not noted as powerhouses as glow but really come into their own as a Davis conversion martin

Very helpful. I have a couple of "LA'" engines and I saw that write-up last year about the .46 LA. I also have an AX which is a good glow engine for sure.

John

JOHN- You are there just get the head for the 46AX , Not being a fan of rear needle valves. I just used an ASP twin needle carb on my AX46 intake full out maybe 70% full open instant response, no bogs, good fuel draw running pressure from muffler to tank quite conventional martin

J_L_G,  the OS 46LA is a good choice for a general purpose diesel conversion. It works really good as a diesel.
  The Supertigre 40 and 51 works good too. The Super Tiger 45 does quite well also.
The Tower Hobbies 46 too.

The OS 65 LA engine is a good one to convert as will the OS 61FX.
The OS 55 AX and 75AX ought to work nice as well.

Any of the Fox engines work good as diesels. The Eagle 60 and 74's are great as diesels. The Fox 45's make excellent diesels too.
The little Fox 15 is excellent as a diesel. Plus the Fox 25's are nice too.

For really big engines the Super Tigre 2300, 3250, and 4500 engines have been converted to diesels and their owners love them.

Earl,
Thanks. I have two .46LA's and one .40LA, one .46AXand I have a .42GP and a .40 FP. I also have a smaller assortment of .25's. So your message is certainly welcome. I think that somewhere in my future is a diesel conversion. Thank you a lot for the suggestions.

JG

The Aurora K-700 7 c.c. (.42 c.i.) diesel

Makes some of the rougher Russian offerings of the past look like precision engineering in comparison...........

ChrisM
'ffkiwi'

The exterior crankcase casting is not of the crisp standard we see from major manufacturers. Bearings (races and shaft) feel smooth and cold, it has excellent P/L and C/P fits.

I will partially disassemble it for cleaning and inspection. It has been run. There is much evidence of congealed castor inside and out. In my experience the real weakness is the conrod. Some are OK, some are atrocious. Crankshafts are also suspect on early Aurora Mills .75's as well.

The generic Aurora diesel instructions are shown below. There is no mention of a "K-700" in the range. It differs from the K-600 and K-650 engines in a number of respects. I suspect very few were made.