Ofna Jammin CR RTR Force .28 Engine

zt-OctaviaN

Hi Guys,

I got a Jammin X-1 CR RTR from Tower Hobbies about 2 weeks ago.
I carefully ran the engine in I mean 12 tanks and idled the first 2 followed by 2 tanks 1/4 throttle then 2 tanks 1/2 throttle and so on anyway the engine does not turn over and theres shards of metal inside this happened whilst trying to start the engine?? Blue smoke was emitting all the time and I had a temp gun and checked it every 2 mins??? also let it cool fully between tanks???

Anyway OFNA direct say they can only support product purchased with US or Canada. Tower it seems dont accept products used??

This is illegal is it not??
Where do I stand any of you had similar problems.??
Regards,
Nick.

g5hn710m4xpdwy

ouch! I cant give you much help but, pity cause its a really nice truggy (it is truggy right?)

zt-OctaviaN

Its the Buggy version......sorry was the buggy version.
Im very dissappointed with it. Cost me a fortune to ship and run in and now its kaput!!

Ill take it very far considering its cost, if tower are unable to to do anything.
Ill get very angry ***Octavian going green*** :P

cheers anyway.

BTW did you order online from anywhere?

Plug

I order of them all the time, no problems.

tallus

Try to buy locally next time heh

coolwings

zt-OctaviaN wrote:

. ... I carefully ran the engine in .....the engine does not turn over and theres shards of metal inside

Not trying to be smart, but have you experience of running engines in?
The presence of bits of metal indicates an experience deficit ...
What you think is careful can actually constitute abuse.

zt-OctaviaN wrote:

. ... Blue smoke was emitting all the time

All this means is that you were burning oil - in other words there were places inside where the temp probably exceeded 600 degrees, the burning temp for many oils. Obviously the piston chamber is one such place.

Two questions arise on this aspect:
1 Were you using over 5% nitro?
2 Were you using synthetic oil based fuel to attempt the running-in process?
If the answer to either of the above is "yes", then you need to know that experienced modellers advise extreme caution and will not themselves attempt it this way.

zt-OctaviaN wrote:

. ... also let it cool fully between tanks???

What was happening in between the times you let it cool?

zt-OctaviaN wrote:

. ...Anyway OFNA direct say they can only support product purchased with US or Canada. Tower it seems dont accept products used?? This is illegal is it not??....

You chose to deal where the sale of goods act does not apply.
So you must now take the repair bill out of the savings you assumed you made when you did that.

BTW Get expert advise before you try again. Unless you identify where you went wrong a repeat of event is on the cards.


As far as identifying what went wrong - can you tell us where the shards of metal came from? This information is important.

coolwings

coolwings wrote:

....identifying what went wrong - can you tell us where the shards of metal came from? This information is important.

For example:

• Broken lower conrod boss = overrevving

• Broken conrod = over revving + high temps.

• Broken upper conrod or piston surface crown = pre-ignition

• Scrapings in piston sleeves = seized and unseized with force = insufficient lubrication

• Scrapings in lower crankcase and sleeves = ingested hard debris (grit)

As you can see from these examples - each particular outcome is caused by the appropriate form of abuse / misuse.

SLIM19198

Coolwings, come on man, take it easy on him!!!

He said he just wasted his savings, stop rubbing it in

Any chance of some pictures of the damage?

coolwings

SLIM19198 wrote:

Coolwings, come on man, take it easy on him!!!

He said he just wasted his savings, stop rubbing it in

Any chance of some pictures of the damage?

Uh Oh ...
Dont mean to be hard on you - I'm really just diagnosing the problem via email. (which leads to being clinincal )
But it's a problem - not terminal.
That is just a broken machine that needs fixing.

A picture would tell us a lot. But the presence of metal is not enough for troubleshooting, we need to know what broke to release the metal bits.

Another possibility, not very often, but once in a while a ballrace goes and breaks. There is a BB at each end of the crankshaft. Often can be a warranty type fault , but may also be induced ... shaft impact / lack of lubrication..

zt-OctaviaN

Cheers for the help.
No coolwings has brought up some valid points of how an experienced person may view how the buggy was ran-in.

The shards well there was shaving albeit small i mean small silver shavings almost flat dust like shavings at seal of the exhaust outlet on the engine case.

I took out the glow plug and noticed something so I turned it upside down and shook it out popped a lump of metal about 1.5mm square and about .7mm in thickness It looked like it was a shared from a cylindrical shaped object. near a top piece as it was slightly freyed at the top of the shard like pottery Pot? I hope this gives clear indication of what the object must have looked like.

I didnt wish to open the engine due to possible breach of warranty.
but I put the lump back in so OFNA would see it.

Im not sure but it doesnt look like it came from the part which moves up and down below the glow plug look like a darker metal. But looking at the edge it looked like brass??
I am technically and mechanically minded Ive just never opened up one of these engines so dont know it inside out.

600 degrees! **** couldnt have been that cos the top of the heatsink was around 180 ish and the hottest reading I could get pointing into the heatsink was 230 and there wer high temps around the clutch bell but on the engine side.
Injested dust unlickly never had the air filter off and break in was done on tarmac. car park where i work.

100 foot would have been the range but only carried this out about half way through the 11th tank.

Fuel 16% odonnell on the label not sure if nitro or oil content but LHS said it was fine for run in aswell. cos Ive heard to stay with same fuel.

Coolwings I now youve built up experience but is there a site anywhere as to where I may obtain better knowledge on running an engine to ensure this cant happen again? You have to admit that I excersised extreme caution within my limited knowledge.
However the documentation with a Force .28 engine is muck it states to run the engine at low revvs for a tank and then start leaning it out!! what? followed by a discrepency in closing the main needle and reopeing say on one page 3.5 turns out and on the next 3?

I did a mmore careful run in than that. there was blue smoke which is indicator of running rich and the temp were fine.

Am i missing anything does this happen alot???

Thanks again guys,
Nick.

SLIM19198

When you were breaking in the engine, was the truck/car/buggy on a block or were you actually running it on the ground (as in moving vehicle?)

coolwings

When you take off the cylinder head (the bit with the heatsink vanes complete with the glowplug screwed into it's centre)

Then you can look down on to the top of the piston (the piston crown).

Now rotate the engine until the piston goes down to it's lowest location.

Next look at the sides of the tube the piston goes up and down in (the sleeve or piston liner).

The liner should be nickel plated, with a shiny silver steel colour, reasonably reflective. The liner sleeve is made from brass with a nickel plating on it's surface.

If the plating has been "peened off" by a scraping action when the piston going up and down while still new, tight, and too hot, or not lubricated enough, then the brass material under the plating will begin to be exposed.

So you would see a silvery tube, but the top 4 - 6mm of the tube would now be brass coloured, instead of silver.

If this is the case - you need a new piston & liner set, to get it running again.

zt-OctaviaN

ha.. nope a friend of mines frien had fallen for that with a truck and queried it that the revs were very high. He was calmly told not to continue in that fashion.

it was on the ground with its wheels on!
Nope I knew about that one also.

I may have said before Ive been wanting one of these for quite a while now.
Have been browsing the forums etc.

Besides I have zero to gain by having this sitting on a bench gathering dust! Thanks for yer help tho!

Any website with tonnes of engine info on it?

Thanks again
Nick

coolwings

zt-OctaviaN wrote:

.....
Any website with tonnes of engine info on it?....

Yes - mine

http://uk.geocities.com/norm_flyer/index.htm

Have a look at the "running - in" page.

vectra

zt-OctaviaN wrote:

Fuel 16% odonnell on the label not sure if nitro or oil content but LHS said it was fine for run in aswell. cos Ive heard to stay with same fuel.
Nick.

Where do you buy the O'donnells fuel?

zt-OctaviaN

Nice page will look into to it when I get a mo.

Cheers
Nick

zt-OctaviaN

Get the O'Donnell Fuel in ModelWorld in Galway €35 per Gallon well US Gallon 3.78Litres.
Hes got different percentage and hes €7 per glow plug OS #8
Seems sound

Unfortunatly his supplier couldnt get the Jammin??
If he could I woulda got it there Id normally shop local unless price is way out.
He does mostly Kyosho stuff stocks the part for Kyosho.
But I wasnt gone on the Kyosho 7.5 RTR.

Nick

coolwings

zt-OctaviaN wrote:

...Fuel 16% odonnell on the label not sure if nitro or oil content but LHS said it was fine for run in aswell. ...

If it say 16% on the label - that refers to nitro %.

You have to understand - I'm not saying you can't run an engine in on 16%.
You can.
But a new engine tends to run too hot - that's why we richen the settings - to cool it and add more oil lubricant (the oil is in the extra fuel supplied while rich). Now a high revving engine tends to be hot too. And nitro adds heat.
More nitro = more heat.
So running-in your new car engine brings these all together at the same time.
So you see that although you can run in on 16% - and many do this. It is doing things the hard way, and you have to exercise a huge amount of care.

To put it another way - I use 0% and 2% and 5% nitro while running in. I would (speaking personally) wait until the engine has loosened up , say at least 2/3rds run-in, before increasing the nitro to 10% and higher.

There is a thread about the Specter buggy on this forum, and if you look it up, there is a lot of info & pictures about running in new car engines on that thread which might be helpful.

zt-OctaviaN

Cheers buddy....

Ill look up the specter buggy. post.
Ill try and get a small tub of Fuel that got more oil for run-in if thats what ya reccomend. Some people state its better to stick with the same fuel you run the engine in on. I was told 16% was fine?

Heat was fine though hmm this is a strange hobby. Heat fine throttle usage fine and the engine pops it lid?
Well I just hope it doesnt happen again.

Cheers for the info guys most appreciated
Nick.

g5hn710m4xpdwy

isnt there services for modding engine that bore out the sleeve? it makes it better? and also porting it does but i dot know what that is ;D

vectra

I know if i had a bad experience like that with an engine i would be looking at other options.
Maybe a Hyper 7 engine or something?

g5hn710m4xpdwy

http://cgi.ebay.co.uk/hyper-7-novarossi-p5-engine_W0QQitemZ270007737828QQihZ017QQcategoryZ19168QQrdZ1QQcmdZViewItem
although he doesnt do paypal, he has 100% positve feedback and tehre good engines

Plug

.28 engine might be a bit pricey, I know towerhobbies will have class engines there;)

tallus

ok slightly off topic here but has anyone else lost posts? I have lost over 800 posts in the last day or so.

g5hn710m4xpdwy

yep everyone has :P tho plug and vectra one of the few who gained post count... some poeple lost 12000+ posts now they higest is in the mid 1000s

vectra

Flunked wrote:

yep everyone has :P tho plug and vectra one of the few who gained post count... some poeple lost 12000+ posts now they higest is in the mid 1000s

Maybe the database will get backed up and put it all in order again.

g5hn710m4xpdwy

tis a bit late to back it up now...

Plug

Ha Ha I will soon be the highest poster hopefully:D

tallus

Plug wrote:

Ha Ha I will soon be the highest poster hopefully:D

Those look like my posts !!!! I WANT THEM BACK !!!!!

g5hn710m4xpdwy

Dont worrie plug was nice and gave you your posts back and ecksor was even nicer nad gave us all them back :P

tallus

woohooooooooooooooooooooooooo! lol

vectra

Plug wrote:

Ha Ha I will soon be the highest poster hopefully:D

No
Soon you will be the biggest spam poster..

coolwings

I lost about 700 posts.

So now I get to do my 1000th post for a 2nd time!

Plug

Everything is back to normal now:(

vectra

Plug wrote:

Everything is back to normal now:(

You still have a too big post count..!! :rolleyes:

Plug

Nope thats my usual;)