Blaster wont fire

[1993Blaster]

I just got a blaster last night for $400 that i cannot get to start.

About the blaster
Toomey Aftermarket Exhaust
240cc bored over
OIl injection tank removed
Sat unused for 1-2 years

I've gone through the following checklist...
*Checked Spark
*Checked Compression (blew finger off, dont have tester)
*Has fuel (used starting fluid too)
*Checked reeds
*Cleaned Carb (was in good condition still)

I have got it to *POP* but not actually start. It simply ignites every so often 1 time randomly.

The only thing I could think it could be now is the Woodruff Key, or compression.

How do I check if the wood ruff key is bad without having to take the magneto off?

 

[darederek]

well for 1 you can't bore out to 240CC. its probably just .040 over which gives you almost no power gain over stock.

2. what jet was in the carb? i believe the toomey uses a 310 or something close to that.

3. i would probably drain the fuel and put new stuff in. get a good quality oil and mix 32:1

4. buy a compression tester and check that. anything below 110 could use a rebuild but should still run. below 100 and it probably wont run.

5. you have to take the flywheel off to check the woodruff key

 

[1993Blaster]

The reeds have a hair gap opening that i can see light through, would that prevent it from trying to start?

 

[darederek]

it could. take the screws out and flip the reeds over for the time being. if that lets it run then you can order some new ones. make sure to use loctite on the screws!

 

[1993Blaster]

The last owner claims it was bored over to 250cc is he mistaken?

Anyway it has a gap after i flip the reeds, it's almost a hairs gap.

 

[darederek]

ya he is. you cant bore over that much. boring does no power at all just to cleanup damage from blowing up. many people think boring 50 thousandths is boring 50ccs when its really not even close

 

[1993Blaster]

So it isnt bored over at all. The cylinder measures 67mm across. It's scared up a bit and the rings are melted to the piston.

it had 40psi

However, it's extremely simple to fix, got it all apart in 20 minutes even though I never touched a blaster before. 6 bolts on the top, 4 on the middle and done.

Trying to decide if its better to do the following...

A Hone out the cylinder sleeve, and just buy new rings (cheapest way)
B Hone out cylinder sleeve, buy new rings and new piston
C Buy new cylinder sleeve, new rings, and a new piston (most expensive way)

What do you guys think?

 

[1993Blaster]

Decided to hone out cylinder and replace piston. Quick question though, i am finding ebay's descriptions for pistons confusing, it says the piston is .25, .50.1mm OS and so on. My piston says 0.50 OS on it. Do they make larger pistons for this motor or are we talking about larger rings on stock pistons??????

 

[darederek]

If your cylinder is 67mm u should have a 1mm oversize piston...

But anyway i wouldnt order a piston yet. You need to take it and have it measured to seehow far they need to bore it. Then they will tell you what size piston to order and they will bore the cylinder to that piston. If you dont have any good machine shops around i would recommend shipping ur cylinder to ken oconnor.