2011 at the Hammond Barn

[Phil Waterman]

Hi All

Congratulations on another fine year at Hammon Barn, thanks Bob for the concept and venue for a shared work environment. Now if I could just find a bunch of CMP nuts down here to share work space and projects.

Look forward to another fine year of entertainment.

Cheers Phil

[RHClarke]

Bob and I rolled out our CMPs this afternoon. The weather has changed for the colder so there is less mud to worry about. Bob's truck started on the very first crank, but the HUP took a little more time to fire up. After warming up for a few minutes, we headed up the road to Bob's house. Unfortunately, my engine wasn't running all that well.

Back at the barn, I checked the wires, plugs and dizzy. All seemed in order. On restart I got the same problem - the engine seemed to be missing resulting in rough acceleration. We did not check the timing as time was running out and I had to head for home.

So, given a 235 engine with a manual choke, what would cause it to idle nicely, but get rough when accelerating? Any thoughts?

[Yeo.NT]

From what information you have provided, this to me sounds either:

Timing - is either to advanced or retarded, or the vacuum/mechanical advance are not working properly

Carburation - The high-speed circuit or the accelerating pump circuit may be dirty or plugged


Neil

[Alex Blair (RIP)]

Originally Posted by Yeo.NT

From what information you have provided, this to me sounds either:

Timing - is either to advanced or retarded, or the vacuum/mechanical advance are not working properly

Carburation - The high-speed circuit or the accelerating pump circuit may be dirty or plugged


Neil

Neil..Can be a little or a lot of both and throw in some rotten gas from sitting around and it could fix up the problems.

[Bob Carriere]

Plugs were sooty but cleanable....... loss of power when throttled hit for accellaration..... almost to the point of stalling...which it did on occasions!!

Problem maybe with big boots and accidently hitting the dizzy while shifting or just plain getting on and off.

Gas.....Yes.... maybe old..... a few gallons fo fresh stuff may help..... with added Sta-Bill for safe measure.

It was running so smooth and accellareted well last time out a few months ago.

Timing will need to be checked..... and man do you have to be double jointed to do that.....even if half the sheet metal is missing it is still difficult to twist your head around to see the pointer and TDC.....

As we will need to disconnect the vacuum advance to tune up we will check the holding power of the vaccum advance diaphram.... or leaks on the way over to the carb.

Two solutions come to mind........ go underneath and once timed properly with the engine turned by hand until pointer is at TDC.... grind a notch in the flywheel where it meet with edge of flywheel housing.... always dark there and easier to see....although it becomes a two men job....

Second temporary solution....cut, fit and install a piece of sheet metal to protect hitting the dizzy......

Hopefully it will not be minus 20C when we do that.....

Boob

[RHClarke]

Originally Posted by Bob Carriere

Plugs were sooty but cleanable....... loss of power when throttled hit for accellaration..... almost to the point of stalling...which it did on occasions!! Problem maybe with big boots and accidently hitting the dizzy while shifting or just plain getting on and off.
Gas.....Yes.... maybe old..... a few gallons fo fresh stuff may help..... with added Sta-Bill for safe measure. It was running so smooth and accellareted well last time out a few months ago. Timing will need to be checked..... and man do you have to be double jointed to do that.....even if half the sheet metal is missing it is still difficult to twist your head around to see the pointer and TDC.....
As we will need to disconnect the vacuum advance to tune up we will check the holding power of the vaccum advance diaphram.... or leaks on the way over to the carb. Two solutions come to mind........ go underneath and once timed properly with the engine turned by hand until pointer is at TDC.... grind a notch in the flywheel where it meet with edge of flywheel housing.... always dark there and easier to see....although it becomes a two men job....
Second temporary solution....cut, fit and install a piece of sheet metal to protect hitting the dizzy...... Hopefully it will not be minus 20C when we do that.....

Boob

Bob, The gas is new. I did not check to see if there was anything caught in the carb (shouldn't be as the breather is covering it). I think it is the boot to the dizzy thing causing the problem. We will see.

I won't be barning it this weekend as I will be down east attending a family funeral. Sometimes CMPs have to take a back seat...

[Phil Waterman]

Hi Bob

I've done just what you are talking about of moving the timing mark to somewhere you can actually see it. The little inspection hatch on the top of the bell housing. I just line the timing mark up carefully through the normal timing window behind the starter. Then with a lettering punch I make a corresponding "O" on the back of the clutch housing in line with a fine wire strung between the two bolts. See the picture.

Not really shown in this picture but something I've started doing as I resemble engine and clutch units is I paint two inches to on the advanced side of the timing marks both new on clutch and on the normal flywheel position. This really helps when the timing is way off to find the timing mark.

I have copies of this photo with my manual on the computer in the shop to remind me on which side of the bolt to wind the wire.

Cheers Phil