wont stay runnin, real boggy
- Thread starter sphynx.0029
- Start date
sphynx.0029
Member
didnt want to have to spend another 100 bux, but it is looking like that is what it is going to entail
andynogo
New Member
Another thing to consider is poor sealing in the bottom end- base gasket, crankcase half gasket, main crankshaft seals or it may just be that your rings are stuffed. Does adding oil make a very large difference in compression at low revs? That would indicate stuffed rings. Good luck.
sphynx.0029
Member
well during the taredown we lost the crankcase gasket and did not replace it but pops says its ok. im not the mechanic, but i understand how it works, kinda. as far as the base gasket, we made one out of 3 layers of manilla folder file cut to match and indian head on the base, in between each layer of manilla and on the bottom of the jug for a good seal. dont think that is the issue as we cant get the dern thingy off now...IT'S ON THERE!!
and tried a few different fuel mixtures first thing to eliminate that issue. also moved the needle in the carb to several positions to see if that would do it too but no good. Even took the carb off and put it on another MB and tuned it just fine, took it to work 3 nights since and not 1 problem other than cold start...that sux BTW...
and tried a few different fuel mixtures first thing to eliminate that issue. also moved the needle in the carb to several positions to see if that would do it too but no good. Even took the carb off and put it on another MB and tuned it just fine, took it to work 3 nights since and not 1 problem other than cold start...that sux BTW...
sphynx.0029
Member
oh and we just decided to build another so look forward to the pix, will be a blue titan trail blazer
A very good way to test if the case gaskets and/ or seals are leaking is to fabricate block-off plates for the intake and exhaust mounts on the cylinder. Use the gaskets as a template for making them. Attach the block off plates to the cylinder, not forgetting the gaskets to seal them. Rotate the crankshaft untill the piston is at botton dead center.
Apply no more that 2 to 3 psi steady air pressure to the engine through the sparkplug hole.
Harbour freight sells small in-line pressure regulators with gauges to assist in this. I recommend modifying an automotive no foul sparkplug adapter (available at any parts store) to connect the air line to the sparkplug hole.
Check all seals and gaskets for leaks with windex. look for bubbles. Leak found, fix it.
No leak found, your problems are elsewhere.
Apply no more that 2 to 3 psi steady air pressure to the engine through the sparkplug hole.
Harbour freight sells small in-line pressure regulators with gauges to assist in this. I recommend modifying an automotive no foul sparkplug adapter (available at any parts store) to connect the air line to the sparkplug hole.
Check all seals and gaskets for leaks with windex. look for bubbles. Leak found, fix it.
No leak found, your problems are elsewhere.
eastwoodo4
Member
good info gearnut.
just so you guys know,the fuel mixture in the crankcase gets compressed when the piston goes down.thats what makes the fuel mixture shoot into the cylinder when the piston gets below the intake port in the cylinder wall.so if you have a leak in the crank case you lose that compression.
just so you guys know,the fuel mixture in the crankcase gets compressed when the piston goes down.thats what makes the fuel mixture shoot into the cylinder when the piston gets below the intake port in the cylinder wall.so if you have a leak in the crank case you lose that compression.
Which can also lead to a lean mixture (due to intake leak), and fighting the carburetor adjustments to fix it right will have you pulling out your hair. The carb is not the problem at all. You will also get a pathetic transfer from the crank cavity through the tranfer ports. Poor off the line power and flat high speed power.
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