Re-circulation system

The Force power

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I removed the lower hose at the front ( way under the Carburetors) oil was leaking out slowly, then pressurized the hose and can hear the air escape (somewhere??)

Does this mean; it's clear from any obstructions?
Are there any screens in the T-fittings/Elbows?

please see the attached Drawing & many thanks in advance
 

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  • Reed Plate and Recirculation System 0E065372 Thru 0E093699 (2).pdf
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Jiggz

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Note, elbows have check valves and also the hoses that connects to each of the intake adapters (carbs area). Most of the time, this check valves gets gummed up and will not operate anymore. Preventive measure is to periodically check and clean the check valves with degreaser solvent. I personally dismount (disconnect hoses from both ends) and then spray them with degreasing solvent. NEVER LET DEGREASING SOLVENT GET INTO THE CYLINDERS! Let dry and test by manually blowing into each end and then reconnect.

Remember, the fuel recirc system operates only at high speed. This is the reason 2 cycle engines struggle after a prolonged idling or slow rpm ops.

Not all fuel that gets into the crankshaft cavity gets into the cylinders. Hence this unburned fuel needs to be diverted back to the intake and this is done through hoses and check valves. However, if these check valves are stuck in close position, the fuel air mix tends to be richer while if it's stuck in open position, it tends to be leaner.
 

The Force power

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Note, elbows have check valves and also the hoses that connects to each of the intake adapters (carbs area). Most of the time, this check valves gets gummed up and will not operate anymore. Preventive measure is to periodically check and clean the check valves with degreaser solvent. I personally dismount (disconnect hoses from both ends) and then spray them with degreasing solvent. NEVER LET DEGREASING SOLVENT GET INTO THE CYLINDERS! Let dry and test by manually blowing into each end and then reconnect.

Remember, the fuel recirc system operates only at high speed. This is the reason 2 cycle engines struggle after a prolonged idling or slow rpm ops.

Not all fuel that gets into the crankshaft cavity gets into the cylinders. Hence this unburned fuel needs to be diverted back to the intake and this is done through hoses and check valves. However, if these check valves are stuck in close position, the fuel air mix tends to be richer while if it's stuck in open position, it tends to be leaner.

thanks Jiggz,

on the previously attached drawing, where exactly are the check-valves? are they the ones that are close to the fuel-pump ?
 

Jiggz

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They are numbered 2 and 5 on the parts list and note there are at least 3 of each.
 

Jiggz

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#2 for sure are check valves. #5 looks more like T-fittings but on the 125HP, the check valves are actually on the elbow mounted on the inspection cover which in this case is #1. Go ahead and disconnect the top most hose from #1, #5 and #2 and you cannot miss which one is a check valve
 

jerryjerry05

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That diagram might be different than his 1990 motor.
The bottom hose to the bottom of the plenum.
It should be able to blow air in.
The fluid leaking out is normal.
Carb cleaner, hook up the red hose and spray into the fitting.
That should dissolve any residue.
Then run it so the junk gets burned.
You change the screens in the recirc system?.
 

The Force power

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That diagram might be different than his 1990 motor.
The bottom hose to the bottom of the plenum.
It should be able to blow air in.
The fluid leaking out is normal.
Carb cleaner, hook up the red hose and spray into the fitting.
That should dissolve any residue.
Then run it so the junk gets burned.
You change the screens in the recirc system?.

Hi Jerry,

Thanks for joining, just so we all on the same page;

The power-head has been replace previously (unknown) and is a 1991--- (has a square Fuel-pump)

The hoses are all black, I'm 99.9% sure the Power head in the attached is the one I have.
I'm trying to establish; where the screens are located so I can prevent pulling unnecessary hoses (maybe brake them)

I'm thinking the engine smokes a lot on start-up & Idle (can't/should't "really" run it with the cowl on) that this has something to do with maybe a plugged Re-circulation system and if not I have to "inspect" Exhaust-plate/Gaskets.

Your opinions are appreciated :)
 

The Force power

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Found it !! I know now what & where the Check-valves are.
#2 + #5 are both check-valves, now will check for blockage
 

Jiggz

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Great. Now if after cleaning the entire recirc system and you are still experiencing exhaust smoke in the cowling inspect the following in this order:
1. Idle boot exhaust - this is located in the mid leg and exhausts to the rear two nostrils. You will need an inspection mirror to see the underside. Make sure there's no tear, otherwise replace it.

2. Exhaust plate gasket, using an inspection mirror ran it around the mating surfaces any leak will fog the mirror.

3. Spacer plate, this is where the power head joints with the motor leg.
 

The Force power

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Great. Now if after cleaning the entire recirc system and you are still experiencing exhaust smoke in the cowling inspect the following in this order:
1. Idle boot exhaust - this is located in the mid leg and exhausts to the rear two nostrils. You will need an inspection mirror to see the underside. Make sure there's no tear, otherwise replace it.

2. Exhaust plate gasket, using an inspection mirror ran it around the mating surfaces any leak will fog the mirror.

3. Spacer plate, this is where the power head joints with the motor leg.

thanks Jiggz,

1. the boot is good ( inspected this winter, when the back cover was off)
2. this is visual ? and I presume between the midsection & power head (I'm not with the motor right now)
 

Jiggz

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Yup, it's all visual. Although I might add, to get an accurate test of exhaust leaks while on the driveway is to submerged the LU under water using a large bucket or trash can. This simulates the motor being in the water with the exhaust snout under water. This creates a back pressure and any exhaust leak will be easily evident. DO NOT ENGAGE PROP WHILE DOING THIS. JUST KEEP IT IN NEUTRAL. IF YOU WANT TO INCREASE RPM JUST USE THE FAST IDLE POSITION AT THE THROTTLE CONTROL HANDLE.
 

jerryjerry05

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MTU0NjY1-652af3df.png
Under the hoses on there's a long (about 10-12") dogbane shaped cover.
That's where the screens are.
You can find them on eBay sometimes or find a smoke shop and ask for pipe screens.

Excess smoke: the more you work on it? the more it's gonna smoke.
It takes a good long high speed trip to burn off the excess fuel/oil built up after working on it.
 

The Force power

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Yup, it's all visual. Although I might add, to get an accurate test of exhaust leaks while on the driveway is to submerged the LU under water using a large bucket or trash can. This simulates the motor being in the water with the exhaust snout under water. This creates a back pressure and any exhaust leak will be easily evident. DO NOT ENGAGE PROP WHILE DOING THIS. JUST KEEP IT IN NEUTRAL. IF YOU WANT TO INCREASE RPM JUST USE THE FAST IDLE POSITION AT THE THROTTLE CONTROL HANDLE.

The boat is in the lake, so there's plenty of water. lol

would I be able? (after I remove the back-cover) seal around the Gasket-plate(with form a gasket-silicone) to reduce the escaping smoke successfully? or am I just wasting my time & I should pull the Power head?
 

The Force power

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MTU0NjY1-652af3df.png
Under the hoses on there's a long (about 10-12") dogbane shaped cover.
That's where the screens are.
You can find them on eBay sometimes or find a smoke shop and ask for pipe screens.

Excess smoke: the more you work on it? the more it's gonna smoke.
It takes a good long high speed trip to burn off the excess fuel/oil built up after working on it.

hi Jerry,

I have the power head with the square fuel pump, but I will keep that in mind to "run the crap" out of the motor:laugh:
 

Jiggz

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The boat is in the lake, so there's plenty of water. lol

would I be able? (after I remove the back-cover) seal around the Gasket-plate(with form a gasket-silicone) to reduce the escaping smoke successfully? or am I just wasting my time & I should pull the Power head?

Need to identify first the source of the exhaust leak. And go from there.
 

jerryjerry05

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I had a leak at the adaptor plate.
Wasn't a big leak, covered it in sillycone and it lasted a LONG time.
 

The Force power

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Need to identify first the source of the exhaust leak. And go from there.

okay,

I did goop some gasket-sealer around the exhaust (rubber) tube but it seemed not to help much.
I noticed in the bottom of the rear cover are two little hole and one of them is missing a plastic plug; is it possible the the exhaust-fumes come from the Lower-unit bubbling up and collect in the mid-section, then enter through the little hole(s)?
When the engine idles in gear the smoke becomes less (this is all when the Cowl is off)

With the Cowl on it does not chock-out when in mid or high speed, only in Idle (boat moving or laying still)
 
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