Powerland 420cc GAB 2.0

[bob58o]

As was suggested to me, I tightened lash to "zero". Still clanked.
Removed the balance shaft. Still Clanked.
Removed the cam, lifters, and pushrods. NO MORE CLANK!
Put cam back in WITHOUT lifters or pushrods. STILL NO CLANK!

So it is in the valve train. I'm leaning towards valve 2 piston interference. I want to check but don't want to remove the head. I need to find my dial gauge and stand.

I've been told that it is the camshaft that makes the noise and only does so with spring pressure applied.

 

[ezcome-ezgo]

Clank is bad. Defeat the clank.

 

[bob58o]

Clankity Clunk, Clickity Clack.
The ups and downs of the piston, Jack.
Around the Rosie, Charles Mosley,
Crankshaft Motion with Go-Fast Potion,
Camshaft Lobes, Nitrous Strobes,
I hear voices with stethoscope probes,
Inside my head, They're Clear, They Boom,
The Clackity Clunk of Impending Doom.


Defeat it? I killed it! LOL

 

[bob58o]

No work today. I was on call.
Going to send it today. At least the motor. Going to fire her up and try to tune the idle jet.

 

[bob58o]

It came with a 32 pilot. I installed a 35 pilot. The 35 pilot was too fat.

How do I know? Glad you asked.

The Idle Mixture Air screw was about all the way out and when I turned it in (just a bit), the engine would stumble and seemed like it wanted to die.

This is because the pilot is too rich. For the engine to be happy, I need to give the idle extra air by backing out the air screw. Ideally you want the air screw about more than 1, but less than 3 turns out. If you are more than three turns out with an AIR screw, you need a smaller pilot jet. Solution - smaller pilot jet and turn the air screw in.

Conversely, If you are less than 1 turn out with an AIR screw that means the pilot jet is too small. You need to limit the air (by turning the air screw in) to make the engine happy because the pilot jet isn't providing enough fuel. Solution - bigger pilot jet and turn the air screw out.

The key to finding the right pilot jet is using the one that makes the engine the happiest when the air mixture screw is about two turns out.

Give me a second and I'll upload a boring video.
The video was trimmed. People don't really like my 15 minutes videos where I just sit there and turn a screw in and out and don't say anything. LOL
https://www.youtube.com/watch?v=PBl-2KJfcPo&feature=youtu.be

 

[bob58o]

Without spending too much timing making sure Camshaft specs and port size were correct....
Here's a 420cc with 10.5 :1 CR, a carb that flows 120 cfm, stock cam,....

Geoff said 20 -22 HP with the mods I did....
My pet T-Rex said about the same...

I do a better one later.

 

[bob58o]

And for the finishing touch....
I ordered this decal!!!

I am very excited for this sticker to show up!!!

I wonder if Nick still has those 212%er patches?

 

[bob58o]

Going to try the stock size idle jet. 0.32mm.
I've used a handful of these OKO flatslide carbs on various stuff. Like every engine I own right now. I have never had to use the enrichment (even for cold starting) with these carbs. Now I haven't tried any of them in the January cold in Chicago, but I guess I thought a properly jetted carb would require choke when cold starting. I don't particularly want to use a choke to start, but it makes me think the jetting is off if I don't need one.

 

[bob58o]

Tried my smallest jet available. I have a .30mm but that is in the 280-0410 212cc Hemi. So I installed the .31mm Jet. We were happier than with the 0.35mm Jet. But I'm not yet satisfied. I took off the air filter and prefilter (which I want to use) and we were even happier. Leads me to believe I'm still a bit fat. Luckily the smallest size available is 0.30mm, so I guess I should order another one of those.

 

[ezcome-ezgo]

Jets jets jets!

 

[bob58o]

At my last job, people would call me Bob the Builder and ask if we can we fix it.
I would tell them to F off. It was adorable.

 

[bob58o]

Ever work a 12 hr shift, ring thousands and thousands of dollars worth of drink and food, get clocked out, count your money, and wonder where the heck your money is????

I can pretty accurately guestimate how much money I should have made in tips based off how much I ring. I rarely make less than 20% of my ring. So if I sell $100 worth of product, I expect no less than $20. If I sell $3000 worth of product, I expect no less than $600. Some tips are crap. Some are great. The law of averages usually put me right around 20%. Except for 1 tab, my tips were good to great today, but when I counted my money I feel like it wasn't all there. I could have bought a few Predators with the money I feel I was missing.

Frustrated. Just like tips, some shifts are great - some are crap. When I have a good shift, I need it to make up for the crap ones. When I have what should have been a great shift and don't come home with the money I feel I should have earned, it makes me wonder if I mishandled money or what? Ugghh.

I don't even like people. You know how many times I have to fake a smile during a 12 hr shift? All of the times. Unbeknownst to me, my smile was discounted today.

 

[bob58o]

Replacement Idle Speed Screw got here today. Ebay seller sent me another one to replace the bent one that came with the carb.

It doesn't fit.

Original screw has 3mm tip and 4mm thread OD. Replacement screw is 4mm tip and 5mm thread OD.

Waiting on a response. But I might just try to drill and tap for the larger screw.
11/64" drill bit and M5 x 0.8 tap.

 

[bob58o]

Well it is fixed. I stole the screw from a 30mm carb and put it in the 32mm carb then I drilled out the hole on the 30mm carb with an 11/64" drill bit and tapped with M5 x 0.8 tap.

Don't tell my friends in China who want to give me partial refund.
They asked if I could order the screw locally in exchange for a partial refund, but it is not a normal screw.

 

[bob58o]

The seller has been helpful and has made attempts to correct the situation.
They asked me how much I’d like for a partial refund.

I said $3. That seems fair to me. That is the cheapest price I could find for the tap shipped from within the US. I already had the tap and drill bit and it is already fixed with the replacement screw they sent me, so no need to get greedy. These carbs are cheap as dirt already. I spent 23.50 on this carb. I should have asked for 3.50 to make it an even $20

 

[bob58o]

Re connected the band brake on the buggy.
It doesn't do much, but it does provide a lil resistance.
Tested out the carb at part throttle.
Basically floored the brake pedal and gave it ~1/4 throttle.
I drove in circles in the yard for about 30-45 seconds trying to hold the throttle position steady.

The engine wasn’t very happy at that throttle position. It seemed to “sputter”.
Killed the engine while holding my throttle position and pulled the plug.

So Rich!!! Time to lower the needle by raising the clip. I think I’m in the middle of 5 positions now. I will raise the clip probably to the highest postion, which will be the leanest setting for 1/4 to 1/2 throttle.

 

[bob58o]

That plug was old and had been used with a too large pilot jet and was ran at low speeds and cold temps.

I changed needle clip to leanest position and used that old plug again to warm up the engine a bit, then swapped in a brand new plug, started the engine,with only a few seconds of idle gave it full brake (what a joke) and 3/8 throttle. I was able to make it around the yard maintaining that throttle position. I probably rode for about 1 minute and killed it maintaining 3/8 throttle.

The engine ran (and sounded) noticeably better with the top (leanest) clip position.

Here’s the plug.
Brand new before running 60 seconds at 3/8 throttle (plus some brake resistance to add extra load on the engine - not sure why I think I need this? To simulate uphill, or mud, or sand??? Or just because I need to keep speeds down to take it around the yard at that throttle position).
I am inclined to try the 2nd from top clip position and repeat the test. If for no other reason, to see if I can see a difference in a plug reading between a needle clip change of one position.

84 degrees right now.

 

[bob58o]

Needle clip 2nd from top.
Engine warmed up on old plug.
1/2 position throttle stop set up.
Rear of buggy jacked up.
New plug installed.
Started the engine, jumped in the seat, applied the brake, 1/2 throttle for 30 seconds, killed engine maintaining 1/2 throttle.

Well I smoked and shredded the band brake.
Here’s the plug.

On both tests, one side of the insulator (same side both tests) got more color than the other.
I show the plug in a few different lighting options so you might be able to see if it shows anything.
Can I read a plug after a plug "chop" and see a difference between the top and the 2nd needle clip position? Not really. The 2nd clip position might have left a bit more color on the plug, the the 1st position seems to leave a smaller area of darker color.

Did I waste my brake? Yes.
Did I learn anything? Not really.
Was it fun? Sure.
Do I still want the wideband O2 sensor/gauge? Absolutely.
https://www.wide-band.com/product-p/apsx_d2n.htm

 

[bob58o]

I started with the middle clip position and it seemed to sputter around 1/4 throttle.
I couldn’t tell the difference between 1st and 2nd needle clip position 1/2 throttle plug chops.

I lowered the clip 2 positions to the 4th postion.
Warmed up engine, installed new plug, 30 seconds 1/2 throttle while holding the band brake.
It looks really dark. The flash makes it seem lighter in color.
The engine sputter seemed to return.

Again, more color on one side of the insulator than the other.
The 4th picture (with the darkest color) was taken with no flash.

I want to retest using the middle clip position at half throttle with a fresh plug. The engine seemed to have a part throttle sputter with this clip position before.

So far, seems like the best pilot jet for me is the 0.030" and best needle clip position is the 2nd from the top.

 

[bob58o]

I might want to try middle clip position plus a 0.5mm washer (shim).
If 2nd clip position plug chop looks lean and 3rd clip position seems to run rich...
Perhaps halfway between 2nd and 3rd position is best.

I've only got 1 brand new plug to test with. I want to get it dialed in as close as possible like this. Then I want to put a wideband sensor on it and see what the A/F ratio is after I attempted to tune without one.