Mariner 4hp 2 stroke

[wiggy]

Got the possibility of buying a 10 year old 4hp Mariner 2 stroke, twist is that it has never been used and is still plastic wrapped and has been stored in a dry garage. What do you recon, could there be any problems having sat for so long? What's it worth?

 

[VicS]

Got the possibility of buying a 10 year old 4hp Mariner 2 stroke, twist is that it has never been used and is still plastic wrapped and has been stored in a dry garage. What do you reckon, could there be any problems having sat for so long? What's it worth?

Fit a new water pump impeller
Check the gearbox oil
Get a bit of oil in around the rings before starting it
Follow the breakin procedure in the manual. A tank full of 25:1 initially I would guess before switching to 50:1


Its worth around £400 I would say

 

[Major_Clanger]

Good OB, basically a re-badged Tohatsu with all the spares still available. As the previous poster, but run it in with a 50:1 mixture before switching to 80:1 using decent mineral or synthetic 2-stroke oil (don't mix mineral and synthetic).

 

[sarabande]

It's worth checking that the small plastic fuel lines and diaphragms in and around the carb are not brittle. If they are OK, I would certainly use a fuel conditioner int he petrol to offset the effect of ethanol fuel (e.g. Briggs and Stratton Fuel Set).

As Vics suggests, increase the oil ratio for two or three tank loads before using continuous high throttle loads.

 

[VicS]

Good OB, basically a re-badged Tohatsu with all the spares still available. As the previous poster, but run it in with a 50:1 mixture before switching to 80:1 using decent mineral or synthetic 2-stroke oil (don't mix mineral and synthetic).

From the manual I am looking at

Mixing Fuel and Oil Use a 25:1 (4%) gasoline/oil mixture in the first tank of fuel. After the break‑in fuel mixture is used up, use a 50:1 (2%) gasoline/oil mixture.

 

[Eric MacVicar]

Sorry for Jumping on this thread but I am really struggling with a Mariner 4HP 2 stroke 1989 rebuild. I bought the engine for a song knowing it would need serious work and everything is going as expected and progressing nicely. I have one sticky problem.
Inside the upper drive shaft oil seal cover, ( directly under the cylinder head) there should be a spring and a ball bearing ( see diagram). It is labelled check valve. I have scoured the internet and I cant find these as replacement parts.

I have two questions.
What is its function ?
Is there an equivalent part number for another similar engine I might try ?

Any help or advice greatly appreciated.

Eric

 

[VicS]

Sorry for Jumping on this thread but I am really struggling with a Mariner 4HP 2 stroke 1989 rebuild. I bought the engine for a song knowing it would need serious work and everything is going as expected and progressing nicely. I have one sticky problem.
Inside the upper drive shaft oil seal cover, ( directly under the cylinder head) there should be a spring and a ball bearing ( see diagram). It is labelled check valve. I have scoured the internet and I cant find these as replacement parts.

I have two questions.
What is its function ?
Is there an equivalent part number for another similar engine I might try ?

Any help or advice greatly appreciated.

Eric

AFAICS the spring is unavailable

The ball you will have to order from a Mercury/ Mariner dealer or find a suitably sized ball bearing

 

[Refueler]

Good OB, basically a re-badged Tohatsu with all the spares still available. As the previous poster, but run it in with a 50:1 mixture before switching to 80:1 using decent mineral or synthetic 2-stroke oil (don't mix mineral and synthetic).

Please do not run 80-1 in this ..... the OB co's experimented with 100-1 for a while - and gave up - reverted to 50-1 ....

I have same engine and various smaller and larger ... ALL run beautifully on 50-1.

As to 2T oil - either use a universal or preferably a TW oil designed for the cooler water-cooled engines. Do not use TA (oil designed for hotter air-cooled engines).

Tip : If you stop engine for a short stop - then OK to use the button. But if stopping for long period / finished for that outing and putting engine away - do not use the button ... close fuel and let engine stop from lack of fuel.
This way - when you next get engine out - you will find it will start easier ... I can leave mine all winter like that and it starts after 3 - 4 pulls next spring.
If you stop and store using the button - its not unusual for you to be pulling that cord till your arm falls off ..... common for all brands of 2str O/bds.

As to the engine itself .. an excellent find ....

 

[alahol2]

As to the engine itself .. an excellent find ....

8 years ago...

 

[Refueler]

8 years ago...

OOOP'S !!

I saw the recent posts and assumed without checking dates !!

Still an excellent engine anyway !!