Rotax 493 oil injection block off

[TDI PILOT]

Anyone know of a oil injection block off kit available for the Rotax 493 rave motor?

[TDI PILOT]

Hard to believe 740 views and nobody runs pre-mix in their cars. To delete the oil injection is really not too hard and you don't necessarily need a block off kit. All that is required is to remove the little plastic driveshaft that spins the oil pump then re-install the pump body or the apparent block off plate that "doesn't exist". Also putting airtight caps over the oil nipples on each intake so the engine doesn't run lean and grenade is critical. Additionally there is an oil line that goes into the crank case that must be kept full. (no real oil consumption, but should be checked periodically) After that remove the oil reservoir and all unnecessary oil lines. Before starting the car drain all the fuel from the fuel cell and carbs, refill with pre-mixed fuel.

From here on out you can enjoy a less cluttered engine compartment and not worry about the oil pump going bad or the 10+ connections on your oil lines coming loose and ruining your engine and the weekend of the guy behind you that drives through the oil trail. This also allows you to use many different kinds of two-stroke oil not just oil injection type oil.

[Jnovak]

No one talking.

[tedsimmons2]

2015 GCR 9.1.1. Formula 500 (F500) Specifications
Section 14 Snowmobile Derived Engines
No component of approved engines may be altered, modified, or changed, nor be of any other than original equipment manufacture unless specifically authorized. Engine components shall be assembled in stock configuration. Stock configuration is defined as including: water outlet elbow, ignition harness, etc.

Also, you might not pass the fuel test if you add oil to the gas.

[TDI PILOT]

No component of approved engines may be altered, modified, or changed, nor be of any other than original equipment manufacture unless specifically authorized. Engine components shall be assembled in stock configuration. Stock configuration is defined as including: water outlet elbow, ignition harness, etc.


Oh, in that case we cant change jetting either then...Nothing but stock configuration!


I don't think this is the intent of this rule. The intent is to outlaw performance enhancing items like High-compression pistons, big bores, milled heads, porting, aftermarket carbs, reed blocks, etc.

This "fuel testing" you speak of is generally a measure of the Dielectric constant number of the fuel. This number is affected mostly by oxygenation levels and lead content in the fuel. Having two stroke oil present in the fuel sample is not going to do anything but lower your O2 levels. In fact, adding oil to an illegal "HOT" fuel could actually make it fall within the limits of a legal fuel test.

[tedsimmons2]

9.1.1. Formula 500 (F500) Specifications
A. Carburetors: The induction system is restricted to two (2) 38mm
Mikuni VM 38 round slide carburetors (except AMW). No modifications
are permitted to the carburetor bodies. The use of any jets or
jet needles is permitted.

[cory mcleod]

Eric,

Glad you posted your question at f500.us. I think you will almost always get better and faster responses to F500 questions there.

I can't speak for Solo, but I can guarantee that you will not be legal if you SCCA road race without an oil pump. Whether it's a performance advantage or not and regardless of the fuel test, you are not allowed to delete the fuel pump. I was busted at the Runoffs one year for not running the crossover/resonator bottle on my 493. No disagreement that it did not give me any performance advantage, but I violated the letter of the law.

Cory

[Jnovak]

You cannot remove the pump or disable it. You can run premix but you must tell tech that you are running premix and you must still pass all the fuel tests.

I do not think there is any advantage in removing or disabling the oil pump.