add two stroke engine oil for k jetronic

[kiyamizio]

hello everybody,

I'm new here and i have a 911s from 1975.
i spoke with a race engineer who's doing Porsche for years.
he told me too add two stroke engine oil in gas tank too heal your kjetronic O-ring and piston and valves.

he says 200ml oil on a full tank of gas.

anyone familiar with this?

or is there some kind of special fluid too service your kjetronic system?\

[Targalid]

Some people use automatic transmission fluid (Dexron III), some use Marvel Mystery oil, in about the same amounts. I use ATF to protect the components during the winter months when the car is parked, one quart added to the final tank full. During the summer I add approximately the amounts advised by your mechanic friend. I never thought about two stroke oil. Interesting idea. I got the idea of using ATF to protect the injection system from a Mercedes mechanic who said that the standard "tune up" in their shop for Mercedes diesels is to fill the fuel filter with ATF to prime the system after an oil change. He claimed it cleaned and lubed both the injection pump and injectors as the new fuel displaces the ATF from the filter. I have used this method for twenty years on all my diesels and it definitely improves engine running. I figured that it ought to work on gasoline fuel injection as well. So far, so good.

[kiyamizio]

The only problem is that gasoline engine don't like ATF since it don't burn completely. Two stroke engine only is designed too burn fully.

[Targalid]

I think you make a good point: Modern two stroke oils have been engineered to be clean burning because of environmental concerns. ATF has worked well for me over the years but I can see that it might worth trying some two stroke oil to see how it performs. I can say I have never seen any residue or other issue with using ATF. The entire fuel injection system seems to function better after a dose of ATF in the fuel.

[fanaudical]

I used to add ~250mL of Marvel Mystery Oil to every other tank of my old Audi with CIS (mostly for intake valve seat lube). This was an "old trick" I picked up from my father for some reason (he had gone so far as to install an auto-oiler on the fuel line to the carbs on his old Mopars).

There was a time that I stopped because I wasn't sure of the benefit. Within 4 tanks I had a sticky fuel distributor; another shot in the tank, quick run of the fuel pump, and all was well. I managed to repeat that a few times to be sure it wasn't a fluke.

I haven't run any yet in the Porsche, but it might make sense. Good point regarding the newer formulations of two-stroke oil.

[kiyamizio]

AMSOIL DOMINATOR® Synthetic 2-Stroke Racing Oil


I want too try this oil it's specially for air cooled and high temperatures.
I dont want oil that degrade my gasoline octane number.

[manbridge 74]

I think the race engineer meant something more like 380-400ml per 22 gallon tank (75 911S). This gives a 200:1 ratio which is what I've generally found most guys claiming is the proper ratio for good lubricity.

Good point about the 2-stroke stuff's ability to burn.

For the ultimate in the nostalgia department via smell, try real castor bean oil. Would probably work well at 400:1.

[Steve@Rennsport]

Originally Posted by manbridge 74

For the ultimate in the nostalgia department via smell, try real castor bean oil. Would probably work well at 400:1.

Probably not a good idea to put ANY castor bean oil in the fuel. I'd recommend leaving that stuff for the 2-stroke engines.

Trust me on this one.

[Lapkritis]

Have strawberry scented 2 stroke oil for my snowmobile...

[esonefour]

My Dad is running Methanol this year in the drag car, soo many flavour additives available from summit.
So how often is this 2 stroke oil dose required every couple of thousand miles? Or 10s of thousands?

[kiyamizio]

200:1 ratio sounds nice too me but I don't want a blue smoking car.

I'm gonna try it. And some more guys should try it and post their opinions here.

[kiyamizio]

Originally Posted by esonefour

My Dad is running Methanol this year in the drag car, soo many flavour additives available from summit.
So how often is this 2 stroke oil dose required every couple of thousand miles? Or 10s of thousands?

I have search for additives but they are expensive and most of them are a bottle each gas tank. I was also thinking about lead substitute and that kind of stuff. I think add a decent amount of 2 stroke oil each full tank would be ok

[fireant911]

This thread (Diesel Tractor Owners - adding two-stroke oil to fuel) specifically addresses adding two-stroke oil in diesels and there is certainly much positive talk about the Walmart Super Tech Outboard 2-cycle TC-W3; however, gasoline engines may not realize the same benefits as with diesel engines. This readily attainable and inexpensive oil may be a very good candidate to experiment with for your test.

[kiyamizio]

Diesel engine are oil burners by nature so it won't affect the combustion process. If have added a little bit of 2 stroke outboard oil too my gastank about 250ml on a full tank. I will keep your guys update about my pro's