Help with Solo 6HP Carb

[Dizz]

I posted about this motor earlier.having carb problems.This is water cooled one cylinder motor.I knew up front that parts would be probally
unavailable.E-mailing Solo USA in Va,although my motor has a decal from same Co&address,has no idea they sold these western German made motors in the 80`s,no parts.
It has 130# comp with 3 pulls,145 with 5.It started up,but I had to pour some gas in spark plug hole,than it ran good in trash can,turned off gas line&let it run dry,and it wouldn`t start next day without pouring in gas again.It has a gas tank on motor,and a hookup for seperate tank.Boy that had it said it got hard to start when last used 6yrs ago.I assumed dirty carb.I now think the fuel pump diaphram got hard.The fuel line goes to fuel pump,but the outside tank line also Y`s into this line.You just turn fuel petcock off to inboard tank to use outside tank.The fuel pump sits right under carb.Then outlet to pump goes up to carb.Since I don`t have the outside tank,and the fuel tank on motor mostly sits above carb(line goes uphill aprox 2",then down a little to fuel inlet on top of carb,but 90% of tank is above carb)I came up with the idea of gravity feed&do away with fuel pump,since gravity should feed carb.The 3HP late model Johnson I
I had 2 yrs ago had this set up,I think.
well,it still won`t start without pouring gas in,and now it seems to starve for gas,like it needed pump,I`d thought a 3/16`s" fuel line would gravity feed it.
I cleaned carb.it has a typical carb with float&2 jets,one in very bottom,I assume this is slow jet.
My problem is,if the bowl gets full,why won`t it start?it shouldn`t need the fuel pumped in under pressure if the bowl is full,should it?Their would be no pressure on carb,if I understand how it works.The pump,or gravity puts gas in carb to float shuts off gas,right?Then as you choke&try to start the vacum of engine copmression sucks gas thru slow speed jet,right?
I don`t know for sure if float is letting enough gas in,float&needle looked good,all passages are clear.
I`ve spent several evenings on this thing,and I`m about to trash it.
Any ideas appreciated?/
regards,Dizz

 

[steelespike]

Re: Help with Solo 6HP Carb

It should run on gravity.Gas is drawn into the crankcase when the piston moves up to compress the fuel mix.Most Service manuals have a diagram
showing basic 2 stroke operation.Sometimes you can find after market manuals at the library.Not likely to cover your Solo but basic operation is the same.
Check inside tank for a strainer.Be sure the tank vent is open and clear.
Be sure all the lines are sound and clean.Open the carb and prove that all
passages and jets are clear.Invert the carb body most carbs the float should be parallel with the carb body when inverted.Check that the choke is closing all the way.See if it will start by blocking the intake with your thumb or hand.
After starting in a barrel or on a boat adjust the idle mix screw to the best setting warm in gear.

 

[Dizz]

Re: Help with Solo 6HP Carb

All good advice,I again found a piece of junk in the low jet.I`t now runs good.It had a handfull of trash&steel washer in tank.i had also found strainer,cleaned it&flushed tank.
Problem now is a lower unit slipping problem.when we 1st got it ,we tried to get prop off to see if it had shear pin.It was froze to shaft.My son suggested we try to turn it off,so he held fly wheel&tried to turn it off.something popped&we thoght we broke prob.It ran fine in water today,but it started to slip in water after 30 min running.Prop shaft in lower unit makes a noise to tell problem in lower unit as it is turned.I haven`t been in any lower unit,but maybe we broke a gear,or hoping we broke a pin that holds drive gear to prop shaft,and its turning there,hitting broken pin&still pulling fine&half throttle.
Would have been fine if we haden`t dropped the ball on our foot!
Will tear into lower unit ASAP.
Any ideas what we probally did?
regards,Dizz

 

[steelespike]

Re: Help with Solo 6HP Carb

You most likely spun the hub on the prop.Many props have a rubber cushioned hub to protect the gears if you hit something.
This can be repaired by a prop shop,if you can get it off.
Be sure there isn't a shear pin.Loosen the prop nut and using a piece of hard wood and a hammer lift on prop and whack the shaft see if you can pop the prop loose maybe a little WD40 or nut buster might help free it.

 

[Dizz]

Re: Help with Solo 6HP Carb

It is not the prob.The prob shaft is turning without the flywheel turning,we`ve had the prob off on river yesterday.Hard to believe the lower unit would tear up before prop,and it does have a slip prob,but it did.It is direct drive,no shifter.

 

[CATransplant]

Re: Help with Solo 6HP Carb

It's probably whatever pin or key attaches the pinion gear to the driveshaft. It also could be that there was water intrusion into the gearcase, causing a rust problem that ruined the pin or key.

Does this lower unit have a cover on the bottom that can be removed or does it have a plate behind the prop with a couple of screws?

Either way, you'll have to dismantle the gearbox to see what the problem is. Without a manual or parts blowup, you'll just have to work your way through the process by looking and thinking.

Be very careful not to damage any seals, since they may be hard to replace. If you do need a seal, take the seal to a bearing house. They may be able to find one for your. Be very nice to the guy at the bearing house, though...it's a real pain to hunt down a seal based on measurements, and seals are cheap.

Since you have the engine running nicely, it would be shame to dump the outboard for want of a small pin or key.

 

[Dizz]

Re: Help with Solo 6HP Carb

It has a cap with 2 allen screws directly behind prop on back of lower unit on opposite side.In the center of this cover is a large plug to check 90w grease.The grease looked great when I checked it before running.their is no lower&upper lube hole to pump in bottom as you watch top till full,just this one large plug.It shows no sigh of lube leaking.With engine vertical oil level was well above hole.Thanks,Dizz

 

[CATransplant]

Re: Help with Solo 6HP Carb

OK. Those are fairly simple. If you pull the two screws, you should be able to slide the prop shaft straight out. Once you do that, you'll be able to see the pinion on the drive shaft. I'm not sure, on that motor whether it's possible to replace the drive pin or key on that without removing the whole lower unit or not. It may be that you have to do that to allow the drive shaft to drop lower in the housing so you can get at what is usually a circlip holding the pinion gear onto the driveshaft. In most cases, removing that circlip will allow you to remove the pinion. The drive pin will probably fit into a slot in the upper side of the pinion gear. If it has broken, you'll want to completely clean out the gearcase to make sure it is gone.

From there, you'll have to figure out the diameter of the pin and it's length. I can't help you there.

 

[Dizz]

Re: Help with Solo 6HP Carb

Will tear into it to see.Again thanks,Dizz

 

[Dizz]

Re: Help with Solo 6HP Carb

I tore er apart.No problem in lower unit.All Gears&shafts&bearings were fine.When we were trying to hold flywhell&turn prop,what we did was un-thread the collar right above water pump.It can un screw turning prop anti clockwise,but normal spin of engine would tighten up.The noise we heard was water pump squeaking,as threads are above pump.
As to slipping in water last night,I don`t know?The rubber bushing in prop between aluminum spline collar that mates to prop shaft,and plastic prop outer housing looks great&soft,and looking at carbon no sigh of slippage?I even held a wrench on collar&tried to turn prop,wouldn`t turn with a good tug.
We started motor yesterday,went straight up river&no slippage.We then went angled acroos&down current and right as motor hit high RPM we heard it,and also several more full throttle trys we heard it.This thing has a 3"longer shaft than a short shaft Johnson.
could we have been cavitating?
the prop pitch is geared fairly low on this,it hit full RPM as we were going up river,and the 6HP wouldn`t quite plane our 12'x 36" jon boat off.You can tell it`s geared somewhat lower than a 6HP Johnson prop.
I don`t know but to try it again?

 

[CATransplant]

Re: Help with Solo 6HP Carb

Gosh..that sure sounds like a slipping hub. You might not be able to make it slip in a static test.

So, mark the hub and the outer part of the prop at the rear so that the marks align. Then, take the thing out and run it until it slips again. Pull the prop and see if the marks still align.

If they don't, then it's prop slippage for sure. You can, perhaps, get the prop rebuilt. It's going to be tough to find a new prop for that outboard.

There's nothing in the rest of the drive train that can slip, frankly. If you've pulled the lower unit apart and nothing's amiss there, then it almost has to be the prop.

 

[CATransplant]

Re: Help with Solo 6HP Carb

One other thought: When the engine's mounted on the boat, where's the anti-ventilation plate in relation to the bottom of the boat? That's the horizontal plate above the prop.

It's just possible that it's too high and the prop is ventilating (not cavitating). That plate, on a little outboard like yours should be even with or below the bottom of the boat. I know...you'll read lots of stuff about AV plates being above the bottom of the boat, but that's for big motors, not for little tiddlers like yours.

Let us know where that AV plate is.

 

[Dizz]

Re: Help with Solo 6HP Carb

Plate is aprox. 2" below boat bottom.Prop hub is marked.Will try again.Just don`t understand why it wouldn`t slip @ 1st going up current in New River,it`s a 400yd wide river with moderate current,in a lare 2 m. long slow hole?
I`ll take it to lake to re-test.Thanks,Dizz

 

[CATransplant]

Re: Help with Solo 6HP Carb

OK, then the prop's not ventilating. I'm almost certain it's a spun hub in the prop. Again, I'm not sure what you'll do about that. Finding a new prop will be an iffy thing, although you might compare it to a Volvo Penta prop from a 6 hp engine of that brand, since Solo bought the rights to that engine from Volvo Penta.

There are a few of the Volvo Pentas around, but you're in for a long search, I'm afraid.

You've eliminated all the other possible problems, it seems to me. As for why it slipped in one situation and not in another, I suggest that time was the factor.

If there is a propellor repair shop somewhere near you, you might take the prop in to them and see what they have to say about it. It's just possible that they might have an answer for you.

 

[Dizz]

Re: Help with Solo 6HP Carb

No prop shop in this state,that I know of.According to local dealer,michigan prop in closing it`s doors.
My feeble minded solution was to drill 3 holes thru prop,rubber bushing&into alum spline receiver.I tapped with 10/32 threads&inserted bolts with red locktite.Won`t have luxury of rubber mount,but the only option I could think of,I only used 2 screws@this point.I still think the screws would shear before prop shaft.

 

[CATransplant]

Re: Help with Solo 6HP Carb

I thought of that possible solution, too. As a last resort, it makes sense to me. Since you obviously have the skills needed to do it, I think you've probably made a good choice.

Sometimes, with older engines by manufacturers who are now out of business, certain compromises have to be made. Now, at least, you'll get to use your outboard until some other part fails that can't be replaced.

 

[steelespike]

Re: Help with Solo 6HP Carb

You need to raise the motor until the antivent plate is at least even with the bottom.(I would raise it till venting becomes a problem)just be sure it pumps water.I think it will plane when you get it right.
You may have to build up the transom to get high enough.

 

[Dizz]

Re: Help with Solo 6HP Carb

will experiment with the height,if I can see that it will run!Thanks for the idea.