'85 150hp vacuum hoses

[fdahl_009]

Hi everyone!

I have an Johnson 150 V6 on which I have completely overhauled the powerhead.
But, I have trouble starting it. It have run for a couple of minutes with the garden hose on, then I went to the sea, and when trying it in the water, nearly no luck starting it. It ran for 20sec, then died. After many many starting attemps.

I have installed an new starter since then, it cranks much faster now.
Spark on all plugs, for the most time it seems like it is not getting fuel, other times the plugs are all too wet, so I guess it kills the spark.

Occasionally it has some loud bangs in the exhaust, I guess an too high afr ratio, too much air over the fuel. I first thought of the ignition sequence, but since it have started and sounded good, pretty sure it is as it should be.

No fuel leaks, new hoses. The only thing I can find that I do not know is ok, is the connection pattern/system of the vacuum hoses and the prime solenoid system to the intake and the carburetors.

If anyone could take the time and explain the connections of the vacuum hoses, I would be happy.
When it ran, it were with all the vacuum hoses connected, single hoses on the nipples, but blocked off.

EDIT: Currently it has around 0 deg ignition when cranking, but I have tried about everything else also..

Fredrik.

 

[fdahl_009]

Re: '85 150hp vacuum hoses

The reason for the engine not starting were pretty obvious.
The key that holds the flywheel to the crank had broke, so the flywheel were mispositioned in relation to the crank.

Have had it for about an hour run on the water today.
As before it gets kind of stuck trying to plane out the boat. Sounds like it is missing an cylinder or two when it happens.

But still - would be great with an explanation with regards to the primer solenoid and hoses.
At least, how should the vacuum hoses to the carburettors be connected?
All three together?

 

[jonesg]

Re: '85 150hp vacuum hoses

vac hoses, are they the recirculation hoses?
Mines a 1994 so it might not be the same,
but they're not straightforward connections, #1 carb doesn't go to #1 cyl.
Don't you have the manual?

 

[testmoron]

Re: '85 150hp vacuum hoses

Those hoses have to be right. I know on the earlier ones, one of those hoses lubed the top bearing.

 

[emdsapmgr]

Re: '85 150hp vacuum hoses

The original factory service manual will show the cold start primer solenoid hose diagram and should show the recirculation diagram. The primer solenoid gets fuel from the main plastic fuel rail and then distributes it to the hose barb on the top of each carb. The solenoid pulses and injects extra fuel into the carbs when cold starting the engine. You can see the factory parts diagram online at epc.brp.com. Those diagrams may help by showing the parts of the system. The recirc hose system scavenges excess fuel from behind the reed boxes and conveys it to the cylinders for combustion. Basically, there are 6 hoses which goes from each reed box to the intake side cover. The recir system is to aid in idling characteristics. It is not uncommon for these hoses to deteriorate over the years and leak fuel/oil and for the brass check valves to plug up and quit working. The parts diagrams usually do a very poor job of showing this system and it's components, but the check valves are shown.

 

[fdahl_009]

Re: '85 150hp vacuum hoses

Ok, thanks for the info.

So, if they are not connected - do that make the engine "dangerous" to use?
Will it result in some sort of failure?

The only material I have for the engine is the clymer 48-235hp, the primer system is not showed as a diagram or explained in detail.

There is three connections on the solenoid. One little on top, a bigger one that takes fuel directly from the fuel manifold, then there is an little one on the bottom.

Should the upper connection connect to all the carburettors, and the lower connect to all the connectors on the intake manifold?

As far as I can remember, there are one from each reed valve, then there are one on top and one between the middle and upper carburettor - making 8 connections in total.

 

[emdsapmgr]

Re: '85 150hp vacuum hoses

If the recirc hoses leak, you will find fuel/oil on the engine. Not really good from a safety standpoint. The primer solenoid does not usually have enough barbs on it to feed all the carbs, so frequently you will find plastic tees in one of the lines which will feed additional hoses. See the parts list.

 

[ezeke]

Re: '85 150hp vacuum hoses

They will be similar to the ones in the thumbnail.

 

[wilde1j]

Re: '85 150hp vacuum hoses

Flywheel keys shear because somebody has installed the flywheel incorrectly. Every time it happens, it damages the flywheel and shaft. Do it enough times and you have junk.

1. The flywheel and shaft tapers MUST be clean and dry. And not all beat up.
2. You MUST use a torque wrench to tighten the nut to ft/lbs specified in the OEM shop manual for your motor.

Failure to follow the rules causes sheared keys and damaged parts.

 

[fdahl_009]

Re: '85 150hp vacuum hoses

They will be similar to the ones in the thumbnail.

Thanks. Only one thing that worries me now. I do not have any connections on the intake bypass covers... Or did I misunderstand the drawing?

After an close look I now see that the crank and flywheel have some small damages and errors that make the conical shape not work as supposed.
As said earlier in this thread - its probably junk now, but I do not want to buy these new.

Have tried with an loctite product and new key now, and it have hold up for the last two days, 3-4 hours of running together.
The small amount of mis-balance I saw earlier is gone now also. So I hope...

 

[wilde1j]

Re: '85 150hp vacuum hoses

Forget Loctite, you MUST torque the nut with a torque wrench to the correct value or it will come loose again (and maybe kill someone) ... have you ever seen a 20# Frisbee coming at your head! I hope for your sake it holds together.

The only possible fix short of replacing the crank and the flywheel is to lap what you have. If too much metal is already gone, that's not a choice, though.

This is the result of an overhaul w/o a shop manual by an inexperienced mechanic.

 

[fdahl_009]

Re: '85 150hp vacuum hoses

The nut is torqued, and added loctite to the key - and on the flywheel / crank surface. Hopefully also to fill the gaps and errors in the surface.

It is an old engine, so apparently there have been some quick fixes on this before. The reason for the key to break was that the nut weren't completely fastened, so the key took all the mass and the flywheel were lifted just enough that the key were not deep enough into the flywheel.

Know this is risky, so have tried to do what I can to feel safe about it...

 

[testmoron]

Re: '85 150hp vacuum hoses

Doesn't one of the recirculation hoses provide primary lubrication for the top main bearing?

 

[fdahl_009]

Re: '85 150hp vacuum hoses

I have two more connections than those shown on the intake in that picture.

They are on the intake, one between the upper an middle carburettor, and one between the middle and the lower carburettor.

These are pretty much in the center of the intake, and center inbetween the carburettors.

I guess if there are an top main bearing lubrication, something will go wrong eventually if I continue using the engine with the lines blocked...

 

[jonesg]

Re: '85 150hp vacuum hoses

Well you =could= always order the factory service manual and make sure its correct before destroying it.
www.outboardbooks.com

Place the other manual in the smallest room in your house,
and put it behind you.

 

[emdsapmgr]

Re: '85 150hp vacuum hoses

The recirc systems on these engines vary based on year. In some years, the systems aren't plumbed to the intake side covers. Check the factory manual for your year for the exact/correct diagram.

 

[wilde1j]

Re: '85 150hp vacuum hoses

OEM shop manual usually have three or four reference photos of the powerhead showing harness and hose routing.