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what are these tubes.

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clrkaw

Member
I have a 1979 mercury v150, its kind of bogging a little, I started looking at it and noticed one of the little tubes that go from the reeds to each cylinder is cracked and spitting fuel, first what is the purpose and can that be the culprit, what is it called so I can replace the part, local auto store does not carry that size fuel line so have to order it but its hard to find parts you don't know names to. Thanks
 
That would be the bleed system.---Ask the dealer for bleed hose.----Most have a roll of it.----Small engine / chainsaw place may be another option for you.
 
It sounds like you are referring to "bleed lines".

Their function is to scavenge left over fuel/oil (and in this case it's the oil that's important) from the reeds and feed to the crank bearings to help keep them lubricated.

They do have check valves at one or both ends designed to prevent flow in the wrong direction and prevent air from getting sucked in where you don't want it if the line fails (becomes detached, removed, broke etc).

However, if the check valve also fails (not totally uncommon) you could be experiencing two issues here.

Extra air getting sucked into the reeds or into the crankcase through the fitting that should be feeding the bearings could account for the bogging.

But more importantly, you are not getting enough lube to one or more of your crank bearings - that can turn a motor into a paperweight.

So if in fact what you have posted about here is the bleed lines, I would replace all of them (if one is cracked the others are probably not far behind) and it would certainly be worth it to replace any check valve, minimally on the ends of the broken line, but doing any others certainly wouldn't hurt.

The motor is getting old and rubber/plastic parts are certainly going to degrade/fail - better to be preemptive.
 
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What simply dumping into the channel/intake port? (can't think of the correct term here - haven't had my coffee yet)

It wasn't clear on the parts list where the bleed line terminated, but if not being used to oil the bearings why bother with it at all? could have simply put a drain at the base of the reeds to let it travel into the lower crankcase if that's ultimately all that it's doing if otherwise just being fed to the intake (??????)
 
Not doubting you at all, that is just kinda contrary to everything I have ever read/heard about their purpose.

Gonna have to fire off a email to Merc's tech support to see if they can explain "what" they are actually for.
 
The bleed/recirc lines do not oil the main bearings!!!! The mains are oiled by a small hole in very bottom of cylinders on the 2.0-2.5 liter motors. The 2 lines on the 2.4 200hp horizontal intake is to pull excess fuel/oil out of bearings. The top main bearing is partially fed with line off lower fitting. Also ask them about your findings on where V-6 motors are made.......
 
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In 1998 Merc applied to have it's facilities in Fond-du-Lac declared a "duty free zone" such that they could import parts from overseas and not pay duty on anything that was then assembled and exported, but would pay duty if the assembled parts were sold domestically - unless they imported a significant amount what would the purpose of the application be for?????.

During 2004 as part of an on-going court case involving Merc, Yami and the trade commission, Merc was forced to provide a list of domestic models that were built with engines that came from Yamaha.

Here's the chart they provided - now maybe they lied to the court...
Mercs with Yami powerheads.jpg

Then we can fast forward a bit to 2007 - long after Merc supposedly cut it's ties with Yami, at least according to their press releases. There is reams of waybills showing what was received by Merc plant 3, the "import warehouse". Now why do you import 135 skids of marine engines when you are producing them "on site" - hmmm, maybe you have to read about the role of plant that receives these blocks and bores the cylinders on site - so if you bore the cylinders does that mean you "made" the motor?

Merc Waybill.jpg

I am really sorry that I have got so far under your skin.

Isn't it just a little bit possible that you were lied to by some rep that either didn't know or didn't want to state that the great American icon "Merc" is just as foreign as most other things on store shelves. And perhaps you should ask him about plant 98, which was the foundry producing flywheels and manifolds, which in 1999 was converted to produce props (which are 100% US made). The foundry was not "moved" it was shut down - hmmmm the plot thickens...
 
For the record, I am the one who posted the question and have nothing to do with any of the arguments, I'm just wondering if that tube could cause my motor to bog, I think I have learned everything about mercury now except one thing, my original question. Thanks to all of you trying to help.
 
As far as the bogging is concerned you need to do some simple trouble shooting.----First is a compression test.------Then check to make sure there is spark on all 6 cylinders.----They run surprisingly well on only 5 cylinders.--------This may also be as simple as opening low speed mixture needles 1/8 turn each.
 
To answer your question one or two bleed lines bad rarely cause a bogg, weak fuel pump diaphram,not running on all cylinders,sync and link off will cause this .


Galamb ...you might reread that waybill as its: 1 skid with 135 cartons for 37590 pieces in seperate packages of something with weight working out at about a pound a piece. The (1carton) notation is because its shrink wrapped.
 
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