At a Lost V Twin sound

[Fox Slaughter]

Well my passenger bank sounds like a V-Twin engine. I put my hand over the exhaust it feels like push push push pause push push push pause. I replaced the header gaskets, replaced the Copper gasket at the collector (even started it up with the exhaust disconnected still heard it). Threw a vacuum gauge on it it read about 21 psi steady as a rock.

I'm running out of ideas of what it could be? I don't think exhaust leak like if a primary tube weld is cracked would cause such a noticeable pause in exhaust.

Any ideas?

[98blackbeauty]

Could be a lot of things, sticky valve, busted valve spring, fouled plug, bad wire, how does the engine sound? like it is missing? does it do this a all or various rpm's

[Fox Slaughter]

More noticeable at low rpms specially up to like 2000. Engine isnt running rough and no codes or flashing SES for a misfire. AFR ratio I think was just slightly high on that bank.

[masterfab]

Could be a lot of things, sticky valve, busted valve spring, fouled plug, bad wire, how does the engine sound? like it is missing? does it do this a all or various rpm's

X2

heres and age old trick. take a dollar bill or thin paper and hold just outside the tailpipe about 1 inch. (hold it firmly) if it starts sucking into the tail pipe you have and exhaust valve issue. do this on both tail pipes if you have duals. if it pushes the bill away from the tail pipe then its not an exhaust valve. then its time for leak down to find out what cylinder. or just take the head off either way i bet you have a bent/broken/valve or valve seat, maybe even a week or broken spring.

[Fox Slaughter]

Well how hard is it to do a cam swap with the engine in the car?

[98blackbeauty]

It can be done, but your pulling heads, exhaust, etc. Personally with lack of wrench room I think its easier to drop engine out the bottom. If you have an exhaust valve issue then your going to want to do both heads. Its soooooo hard to torque head bolts with the engine in the car.

[masterfab]

It can be done, but your pulling heads, exhaust, etc. Personally with lack of wrench room I think its easier to drop engine out the bottom. If you have an exhaust valve issue then your going to want to do both heads. Its soooooo hard to torque head bolts with the engine in the car.

x 2

[zdav28]

I know this is an old thread but did you find your problem. I had the same issue, turned out to be and exhast leak between the head and the exhast manifold. Was told not to use a gasket between the cast iron manifold and the aluminum head.