EZGO 2PG OIL FOWLED SPARK PLUG help!

[JohnnyJohnson]

I rebuilt the engine, new bearings, new seals, gaskets, new carb, new fuel pump, took oil pump off, mixed gas 1:128, new seloniod, have not replace coil or spark plug wire.
I had a race car shop turn the cylinder, it had wrong spark plug, I got the NKG 6578. Gapped at .030.

Also put a new reed valve that is supposed to give better starting???

When the plug is dry it will start and run till you stop then will not start again. Pull plug and it has oil on it.

What did I do wrong what should I redo first?

Thanks for your help in advance, the forums here have helped me a ton in rebuilding this engine.

[cart around]

New carbs are junk. Oil ratio should be 40:1 for first tank. I'm not sure how that plug compares to the ngk bp5.

[CP241]

Originally Posted by cart around

New carbs are junk. Oil ratio should be 40:1 for first tank. I'm not sure how that plug compares to the ngk bp5.

That plug is a BPR4ES. The BP4ES is discontinued. One step hotter than a bp5

I concur about the “new carb”. Do you still have the original old Mikuni? Aftermarket carbs tend to either run really really lean, or really really rich. Sounds like yours is one of the rich variety.

[JohnnyJohnson]

It ran the same with the original carb. I can put it back on. I will have to do some research, that was the plug that came up as the replacement number.

[JohnnyJohnson]

When I search for the NGK BPR4ES several sites list the NGK 6578 as the replacement or it being the same thing. is this incorrect?

[Dabble Inn]

The repair manuals for both 85 and 88 say to use an NGK BP5-HS, a 4 would be hotter but probably ok. I haven't looked but can't believe the 4 is discontinued, I do see the NGK 6578 is the equivalent........

Also, I read the 'H' has a shorter reach at 12.7mm then the 'E' at 19mm. Meaning, you may be using a plug that has a longer reach then recommended so be careful....

What year are you working on? Perhaps different years of the 2pg require different length plugs? I wouldn't think so

[cart around]

Did you barbecue the muffler while it was apart?

What is your compression?

[JohnnyJohnson]

Ok getting a BPR5HS plug.

I did BBQ the muffler.

I have not checked the compression, what should the compression be?

This cart ran fine before I had to rebuild it. it was a barn find, I got it running but it had a mouse nest inside the cover on the jug and over heated that side of the piston.

I am going to put old carb back on, put old reed valve back in, new plug and check compression.

Does 2 cycle oil go bad? the gas that was in it when it was running I had use some 2 cycle oil that I don't really know when I got it. I did get new oil and put fresh gas in it.

[cart around]

Compression new should be 120 psi. Since it actually runs, I will assume that you put the piston in the right direction, and that the rings are on bevel side up. How far will it run, and how fast will it go?

How long does it take to foul the plug?
I know it's a new fuel pump, but when you described the problem, this was my first thought. https://buggiesgonewild.com/showthread.php?t=98839

[JohnnyJohnson]

Fuel was my first thought too but Since it is the same with old and new fuel pump, I don't think thats is it and I put a clear gas line from the pump to the carb so I can see it.

with a dry plug it will start fine and it will run until you let off the gas. then will not start again.

I was thinking about the rings, I am fairly sure I got them in right, what I was thinking was when I was turning the jug back and forth to get it lined up with the bolts if one or both rings could have turn and be on the pin some how.

will a compression test be low if the rings are not correct?