Need a bit of help/input here please. I'm not much of a motor guy, but
trying to learn.
When I first got this 1968 MF10 running back in Jan. I new it wasn't right,
but had to move it. So now I'm getting around to getting it running
better.
Back then, I had to run with 1/2 choke to keep it at idle. High revs it was ok.
So I figured clean carb. Done that. Did the whole service nozzle deal.
I'm pretty sure I'm getting enough fuel to the low speed circuit, because when I
remove the carb, and tip it to the left, I'm getting lots of gas running out
of the vent to the right of the idle mixture screw.
Now when I start it cold, it idles ok, throttles up ok, but as it warms up, it
doesn't what to idle down, until about 30 seconds later, and then has problems idling.
So my thought it was lean at idle. Took another look at carb. Discovered the
flange on the carb that bolts to the the block was deformed. About a 1/32" bow.
Someone must have really reefed on those nuts.
I placed a sheet of emery paper on a flat surface, and leveled off the face of the flange.
Tested after reinstalling, by spraying combustible carb cleaner at the flange, and
throttle shaft. Couldn't really notice any difference. There is a bit of play in the throttle
shaft, but other ones I have are worse.
This is where I start throwing darts. Could it be a bad head gasket? I don't know.
I take the head off. Pics below.
It's hard to see in the pic, but it almost looks like someone took a knife to the
exhaust seat in the block, and the knife jumped as they tried to scrape
the seat.(on the back right side)
The other thing I noticed, is that as I spin it through the strokes, the exhaust
valve rises about 10-15 thou on either the compression, or power stroke(can't remember which one it was) It shouldn't, right?
So, am I looking in the right area regarding this idle down issue?
I hope the pics are clear enough that they might show evidence of something.
And, of course, where do I go from here? Thanks
trying to learn.
When I first got this 1968 MF10 running back in Jan. I new it wasn't right,
but had to move it. So now I'm getting around to getting it running
better.
Back then, I had to run with 1/2 choke to keep it at idle. High revs it was ok.
So I figured clean carb. Done that. Did the whole service nozzle deal.
I'm pretty sure I'm getting enough fuel to the low speed circuit, because when I
remove the carb, and tip it to the left, I'm getting lots of gas running out
of the vent to the right of the idle mixture screw.
Now when I start it cold, it idles ok, throttles up ok, but as it warms up, it
doesn't what to idle down, until about 30 seconds later, and then has problems idling.
So my thought it was lean at idle. Took another look at carb. Discovered the
flange on the carb that bolts to the the block was deformed. About a 1/32" bow.
Someone must have really reefed on those nuts.
I placed a sheet of emery paper on a flat surface, and leveled off the face of the flange.
Tested after reinstalling, by spraying combustible carb cleaner at the flange, and
throttle shaft. Couldn't really notice any difference. There is a bit of play in the throttle
shaft, but other ones I have are worse.
This is where I start throwing darts. Could it be a bad head gasket? I don't know.
I take the head off. Pics below.
It's hard to see in the pic, but it almost looks like someone took a knife to the
exhaust seat in the block, and the knife jumped as they tried to scrape
the seat.(on the back right side)
The other thing I noticed, is that as I spin it through the strokes, the exhaust
valve rises about 10-15 thou on either the compression, or power stroke(can't remember which one it was) It shouldn't, right?
So, am I looking in the right area regarding this idle down issue?
I hope the pics are clear enough that they might show evidence of something.
And, of course, where do I go from here? Thanks