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V Twin Not accelerating, runs terrible

#1

D

Dpwill918

I have A B&G V Twin model number 44P777 that I have just replaced the sump gasket. The motor ran fine before this repair but now it does not sound good (sounds like the choke is on) and when I move the governor off WOT the motor dies. I have removed motor and sump to double check the governor and reset the governor (at WOT turn clockwise and tighten).

Any thoughts?


#2

I

ILENGINE

Have you checked to make sure the choke is actually opening. Have seen stranger things.


#3

D

Dpwill918

The choke is opening.

When I was removing the sump to replace the gasket it looked as if the oil passage tube that runs from the oil pump through the race of the sump up to the crankshaft was installed too far. It went completely through the race and touched the crank. It was all marred and the sump near impossible to remove. I filed the high spots off of the crank but I still had to force the sump over the crank.

My question is if the crank is being held up could this cause my symptoms? Thinking I should tear down again and get the sump to just slide down the crankshaft by filing off the high spots of the scratches on the crankshaft,


#4

Scrubcadet10

Scrubcadet10

Dpwill918 said:
The choke is opening.

When I was removing the sump to replace the gasket it looked as if the oil passage tube that runs from the oil pump through the race of the sump up to the crankshaft was installed too far. It went completely through the race and touched the crank. It was all marred and the sump near impossible to remove. I filed the high spots off of the crank but I still had to force the sump over the crank.

My question is if the crank is being held up could this cause my symptoms? Thinking I should tear down again and get the sump to just slide down the crankshaft by filing off the high spots of the scratches on the crankshaft,
Click to expand...
I would think if the starter can turn it over, the engine will be able to turn itself.


#5

D

Dpwill918

Ok I finally got back to this. I have confirmed spark on both cylinders by removing spark plug to look for spark and with a spark indicator. Checked gap on plugs. Cleaned battery and ground connections. I have also checked valve clearance at 0.006. Fuel pump is working but I cannot even get it to fire on carb cleaner. Compression on both cylinders at 165 but it will just turn over but not start now but it seems to want to start


#6

Scrubcadet10

Scrubcadet10

did you remove the camshaft for any reason? made sure the timing dots were aligned on the crank and cam gears?


#7

D

Dpwill918

I did not do anything to internals, just replaced the gasket and crank seal


#8

Richard320

Richard320

Look for air leaks. Maybe a breather tube left off? If you have gas and you have spark and you have compression, then the only thing keeoing it from going is gas not getting in to the spark and compression. That could be an air leak.


#9

B

Born2Mow

Richard320 said:
If you have gas and you have spark and you have compression, then the only thing keeping it from going is gas not getting in to the spark and compression.
Click to expand...
That's not entirely true. True, the first level of check IS gas, fire and compression.
The second level of check is to make sure each of those is occurring at the correct time. Ignition fire at the wrong time is just as harmful as fuel at the wrong time, as is compression at the wrong time. All those are possibilities.


#10

PTmowerMech

PTmowerMech

Dpwill918 said:
I did not do anything to internals, just replaced the gasket and crank seal
Click to expand...

If you did nothing to the internals, then the timing should still be spot on. Did you happen to check and see if the two dots lined up while you were in there? Didn't accidentally move the cam?
Are the plugs wet after you turn the engine over a few times?


#11

D

Dpwill918

The plugs are wet. I could have moved something while wiping up the oil and old gasket material. The valve timing is off because I have air blowing out the intake. I assume I am setting the valves correctly by 1/4 inch below tdc and set both valves clearance at 0.005-0.006.
I need to take motor off again to check crank/cam timing mark but is there anything else I can check before pulling motor again.


#12

B

bertsmobile1

TDC on the Compression stroke I hope & not the exhaust stoke .


#13

PTmowerMech

PTmowerMech

Dpwill918 said:
The plugs are wet. I could have moved something while wiping up the oil and old gasket material. The valve timing is off because I have air blowing out the intake. I assume I am setting the valves correctly by 1/4 inch below tdc and set both valves clearance at 0.005-0.006.
I need to take motor off again to check crank/cam timing mark but is there anything else I can check before pulling motor again.
Click to expand...

If I'm not mistaken, you can check the timing just be looking at when the flywheel magnets cross the coil. While you're there, double check the flywheel key.


#14

B

Born2Mow

PTmowerMech said:
If you did nothing to the internals, then the timing should still be spot on.
Click to expand...
I once worked on an engine the guy brought in "for just a tune-up". When it wouldn't crank I started looking deeper and found the cam timing was way off. After fixing the cam timing, it cranked right up and ran great. So I asked the guy when he picked it up, had he done any work ? (This particular engine had an intermediate gear between the crank and camshaft.) "Oh yes", he said, "that middle gear fell off when I removed the cover... but I put it right back the way it was."

?


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