Bleed System Alternative?

[mach351]

Well if you think about the volume of the puddling fuel, it’s really not that much. You’d be surprised how much fuel can flow through a 1/8” line anyway. It looks like a lot going through clear tygon, but it’s really not. I mean, how much can really accumulate in that little area….and it only really happens at idle. Anything more than idle and it fuel won’t have time to to puddle. We do it on the race motor to clean it up coming up to the start. I run it that way on my stv also just for the hell of it.

[Glastron1987]

Well if you think about the volume of the puddling fuel, it’s really not that much. You’d be surprised how much fuel can flow through a 1/8” line anyway. It looks like a lot going through clear tygon, but it’s really not. I mean, how much can really accumulate in that little area….and it only really happens at idle. Anything more than idle and it fuel won’t have time to to puddle. We do it on the race motor to clean it up coming up to the start. I run it that way on my stv also just for the hell of it.

Seems cleaner to me than mixing it with the carefully metered fuel from the carbs. No wonder these engines haven't built a reputation for idling well.

[powerabout]

Seems cleaner to me than mixing it with the carefully metered fuel from the carbs. No wonder these engines haven't built a reputation for idling well.

Just be careful when you mod the hose system you leave the system that oils the top bearing

[Glastron1987]

Just be careful when you mod the hose system you leave the system that oils the top bearing

Good reminder, thanks.

[mach351]

The middle mains too….those have to stay in addition to the hose that goes from the bottom bearing to the top.

[Glastron1987]

The middle mains too….those have to stay in addition to the hose that goes from the bottom bearing to the top.

Thanks, another good reminder.

Question... what causes fuel to flow in the right direction in all those main lines? There must be some sort of pressure is the right direction, but what supplies that?

[mach351]

Positive crankcase pressure from the pulse (same thing that operates the stock fuel
pump) and check valves.

[Glastron1987]

Positive crankcase pressure from the pulse (same thing that operates the stock fuel
pump) and check valves.

Oh I get it, thanks.

[Chaz]

So I get that cylinders 1, 3, and 5 are on the starboard bank, and cylinders 2, 4, and 6 are on the port bank.
Also, that a port should be matched up with a reed on the opposite side, but it look like that is not true for #2 and #3. So switching those makes sense to me.


(Port to Reed):
1-4
2-6 (2-5 makes more sense to me)
3-5 (3-6 makes more sense to me)
4-1
5-2
6-3


I may try switching those two and see how well it runs.


...and yeah I saw how some engines connect several of them together, I still think there is hokiness to this system.

Don't look at it like it's a sparkplug wire that has to follow rotation in order for it to work. All it needs is a little crankcase pressure.
From TDC the piston travels downward , building pressure closes the reeds. And pushes a bit of fuel / oil up against the reed block gasket area. The little trough will fill up and push it's way thru the check valve until 115-120* after, when the transfers open. If the hose ran to the same cylinder .. it would be a "early active transfer" that bled crankcase pressure but moved little fuel and air. instead, it feeds into a neighbor that is ascending. If the transfer is still open, it will mix with the column. As the transfer closes it will become part of the next charge being vacuumed in. Once the receiving cyl reach's TDC the check valve from the sending cyl will close and the process starts over again.

Some choose to do away with it all together .. here in Florida we got roped into long Manatee (rich people not wanting fast boat traffic behind their house's) Zones that sometimes go on for miles .. The bleeds do seem to help come off of an idle relatively clean.

I dont know about running lines back to the tank ..

But I do know that running lines back to .. err ... no , make that from a spare battery box ...



to some fittings what gotz the other side lines goin to a scuba tank .. makes em come off idle realllllyyyyyyyy clean ..

[powerabout]

if your not drag racing why change it?

[Chaz]

if your not drag racing why change it?

I think he don't like how it looks .. wants to run one of them Cadillac, letric-vacuum pumps to sweep the crankcase clean ..

[Glastron1987]

Don't look at it like it's a sparkplug wire that has to follow rotation in order for it to work. All it needs is a little crankcase pressure.
From TDC the piston travels downward , building pressure closes the reeds. And pushes a bit of fuel / oil up against the reed block gasket area. The little trough will fill up and push it's way thru the check valve until 115-120* after, when the transfers open. If the hose ran to the same cylinder .. it would be a "early active transfer" that bled crankcase pressure but moved little fuel and air. instead, it feeds into a neighbor that is ascending. If the transfer is still open, it will mix with the column. As the transfer closes it will become part of the next charge being vacuumed in. Once the receiving cyl reach's TDC the check valve from the sending cyl will close and the process starts over again.

Some choose to do away with it all together .. here in Florida we got roped into long Manatee (rich people not wanting fast boat traffic behind their house's) Zones that sometimes go on for miles .. The bleeds do seem to help come off of an idle relatively clean.

I dont know about running lines back to the tank ..

But I do know that running lines back to .. err ... no , make that from a spare battery box ...



to some fittings what gotz the other side lines goin to a scuba tank .. makes em come off idle realllllyyyyyyyy clean ..

Nice explanation... so what I think you are saying is that there is a pretty wide window for a piston moving in the down position creating pressure to match up good enough with a piston with its transfer port opened. Even so, to start, I may try switching 2-6 and 3-5 to 2-5 and 3-6 because that would provide more symmetry in my mind.

[Glastron1987]

I think he don't like how it looks .. wants to run one of them Cadillac, letric-vacuum pumps to sweep the crankcase clean ..

Oh that is interesting. Does anyone really use one of those on a 2.5L?

It's just hard for me to get my head around all the effort and energy everyone puts into the right fuel/air mixture, the right jets, or EFI flashing, etc. and then just dump some random amount of fuel directly into transfer port.

[Chaz]

No the vacuum pump was a joke. They do make power on a four stroke though, up to around 14 inch's of depression. After 17 - 20 , it's too much of a good thing and will dry out the wrist pins .. etc.

https://www.enginelabs.com/tech-stor...d-air-control/

I'm not arguing that bleed lines are some kind of "state of the art" system .. LOL

I reckon if it's on the motor while your "arriving" at your tune-up, it will continue to , provide / hinder / do nothing either way .. once you call it good.

The guys that are never done tuning .. throw that stuff in the garbage ..

https://www.facebook.com/watch/?ref=...0racing%20inc.