BumbleBus wrote:What the photo barely shows (on the right hand image) is that there is a third, narrow nipple also on this pump. A quick google-fu reveals this may be a vacuum line?? Or fuel return line? Anyone know which and what I can do about it? So like... if it's vacuum... port it from the carb? If it's fuel return... return from where? And I read if I just block it off there will be too much pressure? Fuel pressure? Vacuum pressure?
I seem to recall reading a thread (either here or at theSamba) about these fuel pumps that mentions a "drain" from the fuel pump body. Apparently you're supposed to attach a short length of hose to that nipple and run it down to rest on the top of your lower "sled" tin, where it will deposit a nice oily patch that is supposed to get dried up by the flow of hot cooling air. You'll note that the nipple is plumbed into the lower half of the pump, which technically vents into the crankcase, so no fuel pressure or vacuum is involved here.
I've never had or worked on a type IV of that vintage, so maybe one of the other guys with more direct experience can chime in.
BumbleBus wrote:oil leak. I've tracked it to what appears to be the outer #2 exhaust pushrod tube seal. All my pushrod tubes appear "like new". My question is... can long-ish term storage cause the seal to dry up etc. or should I be wondering about another cause. It's only the one seal far as I can tell. I've read this seal replacement can be done without removing the motor/heads on the Type IV and that it's something a n00b like me can probably even do myself in an hour. Might be something I tackle since I can't abide Bumble leaving it's mark too much.
Yes, replacing the type IV pushrod tube seals is eminently do-able by a relative newbie. Head removal is not required, although you do need to remove the rocker arm assemblies, so be prepared to handle those appropriately. It's probably best to do one cylinder at a time if you need to go that far. I would budget more than an hour for the job myself, but I hate to rush things.
It's entirely possible, though, that that one pushrod tube has just crept out of the case enough to start leaking. Before you even start unbolting things, see if you can press it in (gently, using a wooden dowel or plastic thingy on the outer end of the tube after removing the rocker arm cover). While you''re in there, check for the presence and proper installation of the convoluted pushrod tube retention wire springy-things. If you don't have them, then that's probably your problem. If you do have them, make sure that the "flat" parts of the retaining wires are bearing against the
ends of the pushrod tubes,
not sitting
inside the tubes.
If you do decide to replace the o-rings, get Viton ones.
AirHead Parts carries them,