So.. It runs, but it's fouling plugs too quickly

[TwoHundredEx]

The engine is an '84 Suzuki PE 175cc 2 stroke. After finally getting it all set up in the X, we attempted to get it started by pulling it behind the quad.
It really wanted to start at first, and actually did start a couple times but didn't stay on long.
As the night went on it kept getting worse, after a while it just stopped fireing all together.
I took out the plug and it still had a little spark, but was wet. I dried it and cleaned it all up and had nice clean spark, so I put it back in, we pull it again, and it starts to fire, but doesn't last long and eventually stops fireing all together...again. Anybody else have a problem like this? I don't know where to start. We're going to try some nice expensive plugs to see if that helps, but anyone else have any ideas?

[cr480r]

did the engine run when before you swapped it?

[RedRider_AK]

It's slowly getting loaded up with fuel. Try leaving the choke off, pour a little bit of premix down the spark plug hole, and kick it over. Does it start?

Clean the carb and report back soldier!

[NINJA]

How's your ground?

[TwoHundredEx]

Well, it ran in the bike... somewhat. I could usually get it running but it wasn't perfect.
RedRider, that's what I figured it was doing, but wasn't sure how to go about fixing it. We tried it with the choke on and off. I'll clean the carb. tomorrow.
The ground is good... I think, I'll check that again tomorrow too.

[RedRider_AK]

It sounds like maybe your float bowl is overfilling and flooding the engine.

[TwoHundredEx]

It sounds like maybe your float bowl is overfilling and flooding the engine.


Thats what I had originally thought quite a while ago when it was in the bike.
The bad part is, I can't find an online manual anywhere, so I don't know what the stock height is. I had one downloaded at one time but for the life of me can't find it now. Actually, I might have it on a backup HD somewhere. I'll take a look to see if I can get the stock height. IIRC it was 29mm. but I don't want to start messing with it until I get the proper specs.

[bigreddaddy]

Try a NEW spark plug.

[TwoHundredEx]

Try a NEW spark plug.

Yes, I will, and I'm guilty of being a hypocrit because that's usually the first thing I'll tell someone when they ask me about a problem. Like I said earlier, we'll be buying some expensive plugs, we just figured we'd try to get it running anyway.

[Erics350x]

hold the carb upside down and set the float level with the bowl base. also get a new plug and check the flywheel for rust.

[RedRider_AK]

No, I mean the needle wasn't closing and flooding out the carb. What position is the carb in? Is the engine tilted any in the frame? Might just be crap in the carb or a tweaked float bowl pin.

[NINJA]

You know, those expensive plugs usually foul sooner than you standard NGKs. I'm talking about the small electrode made of platinum or iridium types. On most floats, the seam where they're molded together can be set parallel to the gasket surface and that'll get you in the ballpark.

[TwoHundredEx]

No, I mean the needle wasn't closing and flooding out the carb. What position is the carb in? Is the engine tilted any in the frame? Might just be crap in the carb or a tweaked float bowl pin.


Ohh okay, I think I see what you mean now. I think I remember somebody telling me that I can check that by hooking up a hose to the fuel inlet, holding the carb. upside down with the float closed and blowing into the hose, if I can't blow on it it's sealing properly. I think that's what it was anyway.
The carb is sitting pretty flat, and the engine is fairly straight.

[TwoHundredEx]

You know, those expensive plugs usually foul sooner than you standard NGKs. I'm talking about the small electrode made of platinum or iridium types. On most floats, the seam where they're molded together can be set parallel to the gasket surface and that'll get you in the ballpark.

Really? I didn't know that, maybe I'll just stick with the NGK's then.
The floats are the circular metal style so I don't think that's an option. Last time I had the carb apart they weren't leaking either.

[TwoHundredEx]

Well I think I may have found part of the problem.
When we started the night, I had only put a little bit of gas in, but I figured it was enough since gas came out of the line when I opened the petcock. Well, turns out there wasn't enough. When I took off the carb today I figured I'd check, and sure enough, no fuel came out of the line. That would explain why it started at first, then progressively got worse....dumb mistake :D
I cleaned the carb. too, and the float pin seems to be sealing properly. I checked it using the method in my earlier post and it I could blow air through it freely with the float open, and it sealed tight when it was closed.
I'm not sure if we'll get to pull it around again tonight, if not, I'll report back tomorrow.

[Louis Mielke]

Put a new NGK in it. Even if the spark "looks" good it could still be fouled.

[Dirtcrasher]

Does it have good compression?

Does it have a strong spark and a good plug at the right time?

Is the fuel fresh and the right air/fuel mixture is making it's way to the cylinder?

Are there any intake leaks?

If you've got all those things it ought to fire up :beer

Most motors that sit have gunk in the carb somewhere, just make sure that you remove every piece and every jet and use carb cleaner if you haven't done that.

I hope you get it running soon, I wanna know if it RIPS IT UP :w00t:

[Bryan Raffa]

I have a sticker on my bike for that reason..:lol:

[RedRider_AK]

I have a sticker on my bike for that reason..:lol:

:lol: I need a couple of those stickers. I always have trouble whenever I actually turn the fuel off, I forget to turn it back on.

[TwoHundredEx]

:lol: I definitely need a couple of those stickers!

Anyways, I'm pretty sure most have seen build thread showing that it's now running, but it fouled the plug today.
After only about 45 minutes of total ride time, it started doing this a little before I took the engine out of the bike, so I was kind of expecting it.
Fouling it that quick would lead me to beleive it's running rich right?
If I remember correctly, the plug was a little black when I took it out, I'll have to double check again tomorrow though.
I think the needle clip is right the middle slot, if I wanted to lean it out I'd lower the needle right?

[super90]

Well raise the clip/lower the needle, same thing. That should help some but if its still bad I would just get a few jets and experement with them.

[TwoHundredEx]

Okay, that's what I figured, but I thought I'd ask first.
Now, another question. I've never bought a jet kit before, if I need one, do I ask for the one for my specific bike, or tell them the size and brand of carb... or?
Dumb question but I just have no idea when it comes to carbs other than the basics.

[bigreddaddy]

Just curious, have you checked the condition of your reed valves?

[TwoHundredEx]

No, I haven't, but it seemed to run good when it did, so I assumed they're fine.
How would I go about checking them?

[bigreddaddy]

They should be right under the intake. As far as I know the reeds should be flat, maybe with a slight gap.

[RedRider_AK]

You take off your carb and pull the intake boot off. They are under the intake boot, going into your case. They should be flush against the cage, no gap in them. They should also be uncracked and unbroken, obviously.

[TwoHundredEx]

Well after a lot of time spent searching online, I finally found a Clymer manual, and a seperate list of specs. According to the manual my stock air screw setting was 1 1/4, it's at 2 1/2 right now. But if I turn it back in, I'd richening it wouldn't I? Or do I have that backwards...
I also had a a hotter plug than reccomended.
I checked the reeds too.
When you say flush against the cage, you mean tight against the top right?

I also made a curved intake boot so that I could run actually have room to run a filter on it. Anyone see a problem with the way it sits, or will the intake being longer than stock cause any problems?

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