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Old 08-23-2006, 05:10 PM   #16
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Quote:
Originally Posted by Luke W
If everything is tight and you still hear that sound, that's not good. I've heard engines have that same spinning metal sound, and it means a bearing is going bad. With the way you're describing the sound, I'm guessing that's what it is, I just can imagine it would happen this early. However, if you ran the engine too lean in break-in, that's probably what caused it. That same exact engine was my first racing engine and the main problem I had with mine is that the low speed needle was so rich that it wouldn't start. Other than that, nothing needed to be tweaked, for break-in at least...
Oh no... but i just got the engine brand new.

Day 1
The guy at my LHS set the HSN so lean about 1 turn and ran about 3/4 tank before i get it home. I do question him on why the engine require such a lean setting brandnew and he say it normal... anyway, he did had a hardtime keeping it running at more the 2 rounds HSN from close.

Day 2
i try to ran it at 2 turn but not so smooth and i reduce it to 1.1/4 turn and it works normal but abit lean. ran that for 1 tank

Day 3 (yesterday)
I finally gets it smooth running by leaning the LSN because like yours, the LSN are too rich to begin with from default setting. I also set the HSN to +/- 1.5 to 1.3/4 turn... running richer then he LHS guy's setting The sound thingy came at about 2nd tank for the day. In all i only ran 6.5 tank breakin in since i got this engine. The sound appear on the 3rd tank If what you say is true, a bearing going bad,... do you think i'm warrant for a refund or exchange? Will running the engine back to very rich setting help the situation?

Ok, let me better describe the sound... you know the 'white noise' sound you get from your TV set when there's no signal? imagine that type of sound but more metallic kind and softer. You can barely hear it behind the RPM sound but once your ear detect it, it become obvious to your hearing sense. It's not the usual engine's 'empty' metal sound you get when your RPM are low on idle, it's kind of buzzing sound type. Hope my explanation works. anyway, i'll run it later today when i get home and i'll try top record it.

Usually when the engine is running, there should only be the RPM sound and not any other sound right? Will the exhuast produce funny sound even on idling? i'm using OS exhuast too.

Last edited by stonely0; 08-23-2006 at 06:19 PM.
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Old 08-24-2006, 10:48 AM   #17
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Hi guys, latest update... it's confirm that the engine is not right i can feel it. the noise problem is getting obvious. i should have suspect it long ago when i see 2 technician struggling to get it up & running before i bring it home. My experience from my 1st car and engine tells me that this engine is toast & doom on the very first day i bring it home. Damn! i hand sink $1.2k on to this new car and it's problem since day 1. Now i'm trying to convince my LHS to change to a new engine of the same model. The problem are...

1) strange engine 'metal buzzing' sound

2) suspect airleak somewhere but i couldn't pin point because the engine will only wants to run at all needle in lean setting causing very high temperature and flame out.

3) when i try to set all needle to factory setting as recommended by OS's customer service, it still won't run and stall even more often

4) fuel tank seeping out fuel always on full tank.

5) fuel line to carb are full of air bubbles. Possible bad routing of fuel hose very close to manifold/heatsink.

6) when i look into the glow plug hole, i can see brownish stain after 2 tank running with setting from my Lhobby shop guy.

Do you think the above warrants for a replacement set of the engine? Worst thing is they'll definetaly keep it in the work shop for a week... but usually how long will it takes to just replace the engine and fuel tank?

i'm keeping my finger cross. Will update soon.
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Old 08-24-2006, 01:09 PM   #18
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Quote:
Originally Posted by stonely0
Hi guys, latest update... it's confirm that the engine is not right i can feel it. the noise problem is getting obvious. i should have suspect it long ago when i see 2 technician struggling to get it up & running before i bring it home. My experience from my 1st car and engine tells me that this engine is toast & doom on the very first day i bring it home. Damn! i hand sink $1.2k on to this new car and it's problem since day 1. Now i'm trying to convince my LHS to change to a new engine of the same model. The problem are...

1) strange engine 'metal buzzing' sound

2) suspect airleak somewhere but i couldn't pin point because the engine will only wants to run at all needle in lean setting causing very high temperature and flame out.

3) when i try to set all needle to factory setting as recommended by OS's customer service, it still won't run and stall even more often

4) fuel tank seeping out fuel always on full tank.

5) fuel line to carb are full of air bubbles. Possible bad routing of fuel hose very close to manifold/heatsink.

6) when i look into the glow plug hole, i can see brownish stain after 2 tank running with setting from my Lhobby shop guy.

Do you think the above warrants for a replacement set of the engine? Worst thing is they'll definetaly keep it in the work shop for a week... but usually how long will it takes to just replace the engine and fuel tank?

i'm keeping my finger cross. Will update soon.
The piston should definately not be brown after two tanks. At the VERY MOST it should be a very faint yellow color at the END of break-in. You have run it way too lean. Also, you said that your LHS said the engine will be lean in break-in. Not true! It should be rich and should only get about 215 degrees max. Also, you said that the car doesn't move when you have the engine rich and you have to lean it to get it to go...right? Check your clutch settings and make it engage sooner. What car do you have this engine in? Does it have a centax clutch?
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Old 08-25-2006, 02:47 AM   #19
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Quote:
Originally Posted by terrible-t
Here' my 2 cents. Bubbles in fuel line, 2X longer on pressure line compared to tank to carb. Seal line from carb to tank w/ATV sealant. Metal noise in idle only! right!. Adjust LSN to the richer side. The metal sound you hear is like pre-ignition on the engine, or running to lean. When you have the engine running, adjust the idle speed first. Then HSN till you have good accel to idle. Then you adjust the LSN. Turn LSN cw(leaning) till the idle start to rise, and stop. Turn the LSN CCW till the idle spped drops, and add a 1/4 turn CCW. That will let you idle on the rich side. The sound should be gone.
See what happens with that procedure. Let me know.
The hobby shop guy found the tank leaking and re-place a new one. that explain why my all needle had to be so lean and the more i tune the more i'm getting nowhere. with the new tank i can run HSN at 1 3/4 open from close & still a tag too rich but it runs fine as it suppose to be for breakin in.

As for LSN, i got it correct using the 'Pinch' test so that one is done.

As for the brownish stain, strangely it gone now. The guy say it's castor oil buildup and should be fine.

Now, i face a another problem ... when startup from cold, it will not fire up with the carb opening at 0.5mm. I have to switch off the receiver and pull the throttle link to at least 50% opening then it will fire up then immed i switch on the receiver to let it goes/jump back to 0.5mm opening. subsequent start up after that is fine. What is the cause here? the fuel don't get in enough when the crab is open 0.5mm?

As for the constant metal buzz, the guy says it comes from the exhuast and it's common. is it true?
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