MT 32cc won't start....

[BaltiVol]

New to the MT (and real RC for that matter). Bought the MT w/32cc motor for sons for Christmas. Finished 20:1 break-in, replaced fouled spark plug and replaced stock pull starter w/power drill starter from Killer RC.


Have 30:1 gas in the tank and motor won't start. Looks like plug is getting fire (sparking on the exhaust when turning over). Priming bulb is full and when pushed will flow gas out of the tank line into bottom of carb.


Have to date only been pushing it at ~1/3 throttle.


Any advice appreciated on getting this beast fired-off. Thanks!

 

[Phill]

Its a hard one cause it was running.

Flooded from too much cranking maybe?

 

[BaltiVol]

Its a hard one cause it was running.Flooded from too much cranking maybe?

Pulled the new plug and cranked over a few times to try and remedy this. Let it set for some time (~15-20min), tried again and no go.

For the NGK CMR7H plug, what should be the gap distance? One other observation, while the plug did spark to the exhaust manifold when testing, I did not observe a spark across the gap on the plug itself. I did not adjust the gap distance at all (pulled out of box and installed). Could be an issue?

 

[BertR]

I would reset your carb needles to stock settings and give the idle screw a turn in and go from there. I would have to say your flooding the engine. I never gap the plugs I just put em in and go.

 

[BaltiVol]

I would reset your carb needles to stock settings and give the idle screw a turn in and go from there. I would have to say your flooding the engine. I never gap the plugs I just put em in and go.

Thanks. What would be the stock carb needle and idle screw settings to reset 2?

 

[BaltiVol]

Found this in the "TT-5 MT-5" forum. Would this procedure be applicable to the 32cc stock motor?:

FROM the DDM Tech Page:

•How should I adjust the jets on a Walbro Carburetor (WA-167 / WT-603 / WT-668 / WT-257 / WT-813, etc)?

These carburetors require regular adjustment to ensure peak performance, and also to avoid an unsafe lean condition, which can prematurely damage your engine. If you find your top-end RPM's have fallen off a bit, or if you experience lagging or surging, it is probably time to re-adjust the carb jets. To ensure max performance and engine life, follow this procedure:

1) Locate the low and high RPM jets on the side of the carb - they are usually marked with a L and a H. Turn both jets completely CLOCKWISE ( to the fully closed position).

2) Rotate the Low jet counter-clockwise to 1 and 1/4 turns open.

3) Rotate the High jet counter-clockwise to approx 1 and 3/8 turns open.

4) Now, start the engine. You may need to turn the Low jet slightly one way or the other for the engine to start.

5) Adjust the Low jet as desired until the idle is where you like it. Turning clockwise ("CLOSING" THE JET) will produce a higher idle, and counterclockwise ("OPENING" THE JET) will produce a lower idle (and eventually flood and the engine will kill, if you turn it too far).

6) Open the throttle lever to full blast. Adjust the High jet until you get maximum RPMs. Note: this will probably be REALLY LOUD. Listen for the highest-pitched whine to tell you where max RPMs are hit. AFTER YOU FIND THE MAX RPM SETTING, TURN THE HIGH JET COUNTER-CLOCKWISE ("OPEN" THE JET) APPROX 1/16TH OF A TURN TO ENSURE YOU HAVE SUFFICIENT GAS/OIL MIX TO COOL THE ENGINE PROPERLY.

Note: The above are just general guidelines. You may need to adjust both the H and L screws once you begin driving, depending on engine loading, altitude, humidity, etc. The trick is to find settings that work well for you, and stick with them.

Here is some helpful information regarding common carburetor tuning problems:

If your engine stutters at full throttle and cannot reach full RPMs:

The high jet is too far open. Close the jet by turning it clockwise slightly, and then ride-test. If no improvement, repeat until desired results are achieved. Once you have found a workable setting, open the jet approx 1/16 of a turn to ensure sufficient fuel/air mix.

If your engine bogs out when transitioning from low speed:

The high jet is too far closed. Open the jet by turning it counterclockwise until you are at least 1 1/2 turns open, and then gradually close the jet until performance is as desired. Poor engine compression, blocked exhausts, and very heavy engine loading can all also cause bogging.

If your engine idles very fast and kills if you attempt to slow the idle:

You may have an air leak in your intake. An easy way to check for leaks is to spray the intake manifold and area surrounding it with WD-40. If the idle changes after you spray the WD-40, there is an air leak. Common areas for leaks are between the manifold and the cylinder, and between the carb and the intake manifold. Inspect the manifold, carb gasket, and intake gasket for cracks or other signs of damage, and replace if necessary.

If your engine idles but then slowly kills:

Your low jet is too far open. Close the low jet by turning it clockwise until a stable idle is achieved.

•What are the recommended carburetor needle settings for my engine?

DDM recommends the following tuning as a STARTING POINT for tuning your engine:

G230RC / G260RC / CY23RC / CY26RC / CY27RC / CY29RC / GP290 engines: 1 and 1/4 L, 1 and 3/8 H.

__________________

 

[BertR]

If it has a 668 on it reset low to 1 1/4 out and high 1 1/2 out.. Go ahead and leave the idle alone cause it may only be your lsn

 

[BaltiVol]

If it has a 668 on it reset low to 1 1/4 out and high 1 1/2 out.. Go ahead and leave the idle alone cause it may only be your lsn

Thanks Bert. Your talking to a "newbie" here, does "668" refer to the carburator type and how/where do I indentify this?

 

[RampageHopUps]

You have a 668 carb. There are no markings on the carb, but the old timers know. Use the DDM instructions above.

 

[Phill]

The fact that it was running OK before tends to say the settings are OK

Check the inlet,exhaust and head bolts.

If they come loose from vibration you'll get an air leak.

Also to clear it after flooding turn it upside down with the plug out and turn it over a few times then leave overnight

I set my plugs at .020 - .025

 

[Phill]

You have a 668 carb. There are no markings on the carb, but the old timers know. Use the DDM instructions above.

Thanks for clearing that up Rob

I was under the impression it had a bigger carb

 

[RampageHopUps]

As far as I know, it's still the same carb as the 30cc

 

[UrbnRzqr]

Would be nice to know if maybe there was a carb upgrade to meet the increase in displacement.

 

[RampageHopUps]

I will call over and ask. They might not know themselves.

 

[Phill]

Would be nice to know if maybe there was a carb upgrade to meet the increase in displacement.

Daves Motors 32cc Zenoah comes with a WT1107 carb

Thats why I assumed the Redcat one had a bigger carb than the 668

You'll find it in the specs at the bottom of the page

http://www.davesmotors.com/Zenoah-G320RC-Engine-Complete.html

 

[RampageHopUps]

That is a Zenoah engine, not a Redcat. You can't assume anything with HY engines.

The HY 36cc had bigger carbs, but I don't think anyone has really checked the carbs.

 

[Phill]

That is a Zenoah engine, not a Redcat. You can't assume anything with HY engines. The HY 36cc had bigger carbs, but I don't think anyone has really checked the carbs.

My DR came with a CY engine but I assume that's just an HY anyway?

 

[RampageHopUps]

Depending when you bought your DR, it came with a CY the first year, then Redcat switched to the HY brand. Different engines.

 

[Phill]

Depending when you bought your DR, it came with a CY the first year, then Redcat switched to the HY brand. Different engines.

Thanks for that.

I bought it here in Aus through Hobby Warehouse about 18 months ago.

I don't know what I'd do without your knowledge of the product.

I ended up giving up on the CY and put a 4 bolt Zenoah in.

The CY was hopeless which is probably why they changed.

 

[RampageHopUps]

Then you have an HSP model, not a Redcat. HSP can have any motor in it that the distributor wants. So no idea what you had.