All ActivityMost RecentMost LikesSolutionsRe: Onan 4000 Intake Manifold replacement got the same problem. Cant side intake off. not enough room. Hope somebody got idea. Re: Onan 4000 Intake Manifold replacement I have the same problem . Bolt snapped off in intake. Cant get intake off because even if you get the inside bolt off you would loose it and the intake would not side off anyway . hopping somebody can help.