My damn Benelli

I have a Benelli Blazer (circa 1975ish I think). It cranks, but smokes like hell and isn't getting revving as high and when I let it sit there running at full throttle it kinda revvs up and down. I just cleaned out the carb, put in a new plug (anyone know the correct gap, i just used what the old one in it was set too). I drained the tank and also used a mix of 43 to 1. I also put in some trans fluid but I think I put too much, not sure.

this thing is in awesome condition for its age with a little more than 600 miles on it, and I would really love to get some use out of it, any help would be greatly appreciated


Re: My damn Benelli

Jason Luther /

make sure the fuel valve and line are clean. sounds like it isnt getting enough gas. my benelli (from the 60's though) has a plug gap of .030". the level and type of the trans fluid is also important.-jason

Re: My damn Benelli

I'll check the line and the petcock again, how do I check the trans fluid? There are 2 Bolts (the big ones to fill, littel one to drain I'm assuming). I'm using Pennzoil dexron-III/Mercon.

My brother thinks the rings are stuck, the piston moves freely but i haven't torn it down yet to check the rings. Also the plug (a new one) got alot of carbon on it really quickly, any ideas?

Re: My damn Benelli

reving up and down points to inconsistant fuel delivery. Make sure a steady stream of fuel is available to the carb. Pull the fuel line and drain some fuel into a container.

Reving up and down can be caused by a changing fuel/air mixture. Check for vacuum leaks. Get some Starter Fluid and spray it around the base of the carb and near the base of the cylinder.. Check the torque of the head bolts.

Lots of smoke may be from an accumulation of oil in the muffler.

You should at least pull the head and look at the piston and cylinder.. see whats up in there.. Is the exhaust port clogged with carbon? the piston top and combustion chamber? Cylinder sides walls look OK?

If you feel like it, pull the cylinder off and look at the rings, but unless theres a ton of carbon under the head they are probably ok. You will most likely destroy the cylinder base gasket if you pull it so don't do it unless things lead you in that direction.

You can seee the rings, or part of them, through the exhaust/intake ports on the cylinder.

Re: My damn Benelli

thanks, i'll check it out

Re: My damn Benelli

thanks for the advice

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