Embarrassing question

jimmbo

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May 24, 2004
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A Compression test only reveals issues with the Cylinder, Pistons and Rings. It can't indicate any Damage to the Crank, Connecting Rod, Piston Pin Bearings or to the Crankcase Sealing Rings. The Cylinder Walls actually require very little Lubrication.
 

F_R

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It would self-destruct in less than 15 minutes if run on zero oil in the gas. Your mileage may vary.
 

airshot

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You should add 2.5 oz of TCW3 oil for each gallon of gas !! Add oil first, then add fuel to be sure it is mixed properly.
 

jefsummers

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May 6, 2023
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Just back from store bought tcw3 oil. Although running with out oil could certainly do the problems mentioned. I am hopeful that I am doing okay and will add a double dose of oil to the current gas and will add oil to each subsequent. Can. I also have a jet ski that runs on regular gas and a Tahoe that runs on regular gas as well as a generator that I need to depend on that runs on regular gas. So I will need to get some new tanks for the mixed gas.. šŸ˜Š
 

saltchuckmatt

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50 to 1 will be 16 ounces per 6 gallons of gas not what was mentioned before.

Also, just like Racerone recommended, compression test. It will give you indications if you have internal damage
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Why wou you run the boat in winter?

Drain your fuel system, fill with proper mixed fuel

Check your compression. If it still runs. Buy a lottery ticket
 

racerone

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Post # 5 suggested a compression test on a hunch.-----Looking forward to the numbers you get.
 

909

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If the dealer sold you a 4 stroke, bring it back to him and tell him he gave you the wrong one.
 

jimmbo

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May 24, 2004
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Just back from store bought tcw3 oil. Although running with out oil could certainly do the problems mentioned. I am hopeful that I am doing okay and will add a double dose of oil to the current gas and will add oil to each subsequent. Can. I also have a jet ski that runs on regular gas and a Tahoe that runs on regular gas as well as a generator that I need to depend on that runs on regular gas. So I will need to get some new tanks for the mixed gas.. šŸ˜Š
Extra Oil will not repair any scoring/scuffing if it has happened. If the Fuel-Oil was diluted to 100:1, the engine should be okay, the 50:1 ratio is more Critical at High Load High RPM
 

stresspoint

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adding a double dose is not the answer , add what is required to the amount of fuel you are putting in , 50;1 or there about .

100: 1 is border line for hit or miss as far as engine damage , those V4s are a robust little sod , guessing if you did not do high RPM running your motor will be a survivor.
i used to run my jet skis 100:1and they were pinned flat all the time , however top end rebuilds were regular.
 

tpenfield

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@jefsummers - you mentioned having previously owned a Suzuki 2-stroke (right?) I'm assuming you had to add 2-stroke oil on a regular basis? Perhaps the Suzuki was oil-injected? Back in the day (1970's) we had to add the 2-stroke oil to the gasoline . . . (very primitive, I know :ROFLMAO: )

Based on your description, you probably ran the engine on a 100:1 mix for the time you described over the winter. So, maybe not fatal, but not a good thing either.

I have a small Yamaha 2-stroke OB that states 100:1 oil mix . . . that seems light to be, so I run it at about 75:1. Anyway, your new-2-you 1970's outboard probably runs on a 50:1 gas/oil mix.

It's a good thing you signed up here at iBoats and asked the question. Hopefully all will be good.
 

jefsummers

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May 6, 2023
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- Compression test equipment should arrive tomorrow
- Have read manual (I have a service manual, not the original owners manual) regarding how to do the compression test. Will read at least one more time and keep with me when I do the test. A YouTube or 2 might help as well.
- Did mix oil and gas in the Suzuki, but believed that this was 4 stroke. Should have checked more into it earlier and agree that it is a good thing I signed up here and asked!
- Double dose of oil in the 5 gal can I added to get the concentration closer quicker. No easy way to get it out of the water without running it farther than I am comfortable until I get things straightened out, so not draining the gas tank.
- Did run it a couple miles yesterday after adding the extra mix, ran fine. Hopefully did not damage too much.
 

jefsummers

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May 6, 2023
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Ran the compression test - ran the boat for 10 minutes, then pulled all plugs and disengaged the ignition (kill switch). Plugs look pretty good. Wife cranked for 5 seconds twice on each cylinder while I watched the gauge. Looked pretty consistent, 52-55 psi across the 4 cylinders. The kit I have does not hold the peak pressure, so it was bouncing up and down at the rate of turning over, but could get a pretty reasonable read. Wife rewarded me by letting me take her for a 20 minute cruise and ran fine.

Thanks!
 

racerone

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Throw that compression tester away and get a good one.----Should read about 120 + PSI on a good motor.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Agreed, either your compression test gauge is junk, or your motor is junk.

should be 120psi.
 

tpenfield

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It does not sound like you have the proper compression tester, or that it is not working properly.

There should the a check valve so that the gauge continually climbs, as the engine is cranked, but the gauge should not go down until you release the check valve.
 
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