Thread: 2 stroke ain't dead yet....

2 stoke boat engines will soon cease production, it isn't a fuel efficiency problem it's the oil they put in the water & it is HEAPS.

If you want a 2 stroke then click away.....High Power Density Pivotal Engine by Pivotal Engineering Ltd - Christchurch, New Zealand

Originally Posted by twitchy

2 stoke boat engines will soon cease production, it isn't a fuel efficiency problem it's the oil they put in the water & it is HEAPS.

If you want a 2 stroke then click away.....High Power Density Pivotal Engine by Pivotal Engineering Ltd - Christchurch, New Zealand

I'm interested to know how a two stroke outboard puts oil in the water when they don't have oil in them.

I can understand a four stroke outboard doing this if the engine developed an oil leak.

Dave.

Originally Posted by Captain_Rightfoot

You try and buy a outboard. Sure there are 4 strokes, but the direct injection 2 strokes are really putting up a strong case. They don't use much (if any) more fuel than the big 4 strokes, they are lighter, and have a fraction of the maintenance requirements. Also, they use hardly any oil. In the case of the e-tec - they can actually run without oil for many hours at reduced power settings.

I was looking at a new 200hp Merc for my boat a couple of years ago and I toyed with the idea of a four stroke for fuel savings.

I was told by the dealer that the two strokes use considerably less fuel than the four stroke.

This is apparently due to them using the fuel system from Ralph Sarich's orbital engine. Although the orbital engine is dead and buried the fuel system is being used by Mercury outboards.

Dave.

Originally Posted by V8Ian

One of the early model Hondas (Scamp, Zot??) had a starter/generator as a single unit. Other manufacurers have used the same idea..

About 30 years ago I had a customer who had a Honda Scamp with this unit. When it failed to charge I had to remove it to send to the auto sparkie.

What a nightmare it was to remove it from the vehicle.

Dave.

There is an Aprilia 50cc scooter that was/is available in aus. It had the Sarich DI technology, and it was capable of 110 kph and used less fuel than the normal 50 cc scooters.

It was sold governed, but if you had the appropriate licence you could ask the dealer to remove the restrictions. That is truly impressive, IMHO.

Originally Posted by Mr Whippy

I'm interested to know how a two stroke outboard puts oil in the water when they don't have oil in them.

I can understand a four stroke outboard doing this if the engine developed an oil leak.

Dave.

The exhaust on a boat motor is UNDERWATER, hence the oil smoke you normally see in the air gets pumped into the water instead!!!

Originally Posted by Brian Hjelm

They have exhaust valves. The blower scavenges the burnt gases and charges the cylinders with fresh air through an air box and cylinder ports.

Wonderful engines, Detroit two strokes. Keep good filters on them and they run clean and cool almost forever. I had 6V53N's in a boat and a Bedford KMR-XT5 single drive prime mover and some 8V92TA's in line haul and road train movers. The road train one was tickled up to marine specs, 545 BHP @ 2300 rpm. It could really march.

Sorry Brian you're right...seems I can't think and type at the same time! Yea intake ports around the cylinder and exhaust valves in the head. Don't know why I typed that.

Originally Posted by vnx205

The Haflinger had one.

Actually most cars prior to roughly mid 20's had an integral starter/generator - dodge used them up till 1925/26.