V4TL-13A Compression Validation

[Searayyed180]

Hello, I have a 69' SRV 180 with a Johnson Evrinrude 100hp meteor and this motor as a 2 stroke raises concerns as far as longevity and reliability. This motor has consistent compression of 110psi through out 3 cylinders and the fourth one was at 95 psi. Are those concerning numbers? What would be a plan of attack, replace cylinder rings? Motor runs pretty smooth, so I can't say it is affecting the motor at all. I don't have very much background on these motors so the more the info the better.
Thanks

 

[racerone]

Those are just an excellent / simple / reliable motor.----Bullet proof electric shift lower unit.-----The 1966 battery / coil / points distributor can be retrofitted.-----I would remove the bypass cover to look at pistons / rings.----Possible a blown head gasket.----Your location ?

 

[racerone]

Pistons / rings are available in 0.020" and 0.040" oversize if you need to repair the one cylinder.

 

[Searayyed180]

Those are just an excellent / simple / reliable motor.----Bullet proof electric shift lower unit.-----The 1966 battery / coil / points distributor can be retrofitted.-----I would remove the bypass cover to look at pistons / rings.----Possible a blown head gasket.----Your location ?

That’s really good information! I will attempt as soon as I can. From those numbers should I replace all four cylinder rings/ pistons and oversized ring/piston for the low compression cylinder ? Otherwise I feel like you support rebuilding the motor, because I’d like to buy a four stroke eventually but if I don’t have throw in thousands of dollars I’m game to fix this motor up!

 

[Chris1956]

That is a 50 year old motor. Run it as is. It is just out of spec for even compression.

 

[jimmbo]

WOT Rpm range 4500-5500
Mix fuel @50:1, use TCW-3
Requires BRP Premium Blend Oil for the Gearcase. This was originally called 'Type C' Gear Oil. There are some 3rd Party Brands, but not all are compatible with the 'Electric Shift' so beware.

The rings might be a little Sticky, so a can or two of Engine Tuner, or Merc Power Tune, might loosen them up.

 

[racerone]

Remove the bypass cover and inspect before ordering any parts !!----I remember friends with the 66 model METEOR.------Lots of weekends it would hardly cool down.----Pulled 2 skiers on slalom skis in deep water starts and 17' boat.----It survived brutal punishment.-----Lots of used parts available as well if you know where to look.

 

[jimmbo]

Saw one of them about 10 yrs ago

 

[racerone]

Great rugged motors !!----Have one myself here.-----Have a rare short ( 16" ) lower unit that I might install on a 1960 Leavens 15' boat with wings.

 

[Searayyed180]

WOT Rpm range 4500-5500
Mix fuel @50:1, use TCW-3
Requires BRP Premium Blend Oil for the Gearcase. This was originally called 'Type C' Gear Oil. There are some 3rd Party Brands, but not all are compatible with the 'Electric Shift' so beware.

The rings might be a little Sticky, so a can or two of Engine Tuner, or Merc Power Tune, might loosen them up.

I will give that engine tuner a try and also I found a brand “Sierra Quality Marine” for gear oil because my bottom end took in water milky white so I know I need to replace gaskets and impeller before taking it out on the water. Also the spark plugs L78V are almost flat compared to anything I’ve seen is there any benefit to getting a different style or stick with stock ? Thanks.

 

[Searayyed180]

Remove the bypass cover and inspect before ordering any parts !!----I remember friends with the 66 model METEOR.------Lots of weekends it would hardly cool down.----Pulled 2 skiers on slalom skis in deep water starts and 17' boat.----It survived brutal punishment.-----Lots of used parts available as well if you know where to look.

I will definitely take a look prior to making that decision good thinking

 

[racerone]

Install a complete seal kit in the lower unit.

 

[jimmbo]

I will give that engine tuner a try and also I found a brand “Sierra Quality Marine” for gear oil because my bottom end took in water milky white so I know I need to replace gaskets and impeller before taking it out on the water. Also the spark plugs L78V are almost flat compared to anything I’ve seen is there any benefit to getting a different style or stick with stock ? Thanks.

Does that Sierra Oil say it can be used in Electric Shift Lower Units?

 

[Chris1956]

Are those the correct spark plugs? I though they were all J4C Champions.

Remember to disconnect the electric cables to the gearcase, before dropping it.

 

[jimmbo]

a 1966 used J4-J, but in 67 when the Engine acquired Electronic Ignition, the plug changed to the Surface Gap type

 

[Searayyed180]

a 1966 used J4-J, but in 67 when the Engine acquired Electronic Ignition, the plug changed to the Surface Gap type

The Spark plugs are surface gap yes. Also I need a new hydraulic steering system helm/ steering system any suggestions?