2-Stroke oil in fuel for Classic cars?

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FCD

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When my friend who has multiple Vintage VWs told me that he put 2 stroke oil ( 1% ) in his fuel i was a bit baffled, apparently it protects the fuel systems on classic cars that were supposed to run with leaded gasoline, and also helps against the negative effects of modern fuels with ethanol in them, and since my car never had hardened valve seats put into the cylinder heads i wonder if this could be a good idea.
He uses API TC Smokeless 2 stroke oil.
Thoughts?
 
Lots of folks use 2 stroke oil as an upper cylinder lube. I saw in someone's signature on here they run it somewhere around 400:1 in a new vehicle. I run it at 128:1 in my older Cummins because new ULSD diesel is a lot more "dry" (not as oily) as old diesel.

I can't comment on protecting your exhaust valve seats.
I'm sure there will be some benefit, just not sure how much.
 
The theory is that it can help with valve recession... but I'm not convinced. 2-stroke lube just results in a lot of carbon being produced during combustion that shouldn't normally be produced in a clean-running 4-stroke engine. While oil in the incoming mixture might theoretically lubricate the intake valve seat, no liquid 2-stroke oil is ever going to find its way to the exhaust valve seat because its going to get burned during combustion, and the EXHAUST seat is the one that usually burns. Adding carbon to the combustion chamber is just going to lead to hot-spots that aggravate pre-ignition and detonation, so I think the negatives more than offset any (theoretical, un-proven) benefits.
 
Is there any truth then that it could help itigate the effects of ethanol in classic cars fuel systems?
I mean right now i exclusively use BP Ultimate 98RON because i know it doesn't have any ethanol, but it would be nice not having to find the nearest BP station when you're far from home and running out of gas.
 
I've been adding 2 stroke oil to my motorcycle fuel in the ratio 1:640 for 5 years. It must be TCW3 which is the marine spec so that it will burn without leaving any ash deposits. Far from depositing carbon in the combustion chamber I see the opposite effect as over a long period of use the detergents in the oil have a noticeable cleaning effect.

As an amusing aside the F1 boys must have been at it as they are about to be banned from the engines deliberately burning their own lubricating oil.
 
I don't know if you've been around any outboard engines, but they stink because of the burned oil in exhaust. Most 40+ year old engines that are run enough to wear their valve seats have already been rebuilt with hard seats. Those that haven't been are super low mile collectables that don't see enough run time to wear anything.
 
Outboard engines are running a ratio of something like 1:33 so they may well stink. A ratio of 1:640 in a 4 stroke engine doesn't smell at all or show deposits in the exhaust. Besides the cleaning effect in the combustion chambers, the only other visual result is a very slight colouration of the spark plugs, not carbon deposits, just a subtle colour that you wouldn't normally see.

The only other firm evidence of an effect that I'm certain of is it eliminates mild pinging when I run what is a 98 Ron engine on 95 Ron. Can't explain the mechanism but it does.

Valve seats I don't make any claim about. I do have original cast iron seats and don't seem to suffer from valve recession on the evidence of no measurable change to valve clearances at an annual check. But that's only 3000 miles per year and there might be no change with or without adding TCW3.

I like to think there is going some lubricating effect on the carb slides but have no measurements to confirm one way or the other.
 
Well, i guess it wouldn't be a bad idea to just try it out.
I don't think my engine has much valve seat recession, i mean we did have leaded gas at the pump in Spain until January 1 2002 so the engine has been running fine un Unleaded for 15 years.
 
Originally Posted By: Linctex
Lots of folks use 2 stroke oil as an upper cylinder lube. I saw in someone's signature on here they run it somewhere around 400:1 in a new vehicle. I run it at 128:1 in my older Cummins because new ULSD diesel is a lot more "dry" (not as oily) as old diesel.

I can't comment on protecting your exhaust valve seats.
I'm sure there will be some benefit, just not sure how much.


define dry/oily.

I think youre mistaking it for lubricity due to the sulfur bound aromatics...


OP, yes it can provide some benefit by offering a minimal oil film on some parts potentially, as well as often including a fuel stabilizer, which is helpful for cars that sit a lot.
 
I run it 640:1 in everything 4 stroke I own, 10 quality engines all run perfect...save the nasty little oil diluter 1.5T
 
I know of a fellow whom I 've grown to respect in the 17 yrs I posted to him on the FSJ page. He used a tiny amount of TCW3 in the gas he put in his 401 V8 in a 70s Jeep Wagoneer. His hobby was taking the highest passes he could find in Colorado with the Wag. He did over 200 of them before he retired the Jeep. It is like MMO only different
grin2.gif
 
I heard from someone here it's mostly kerosene with additives..was worried for Ca in the diluter but that's not included in TC-w3.
 
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I've read before that the only time you get recession on valves is when you run the engine at over 3500 rpm's or under hard loads. Just regular low rpm driving shouldn't hurt the seats, i don't think.
 
Originally Posted By: FordCapriDriver
When my friend who has multiple Vintage VWs told me that he put 2 stroke oil ( 1% ) in his fuel
Thoughts?


1% seems quite a lot. OTOH I don't know why people pick 640:1 (why not, I suppose). Wouldn't have thought there was anything special about that ratio.

I've considered it, but

(a) I don't want to reduce my headroom on the HC emissions test.
(b) Although 2-stroke oil is still widely available here, finding stuff I knew met an ashless marine spec. might be difficult or impossible.
 
There is no question that adding a bit of oil to gasoline can make certain engines run smoother. Even modern engines.

In fact, there are some on this forum who swear Marvel Mystery Oil (or two stroke oil) make their engines run smoother. The additional lubrication may play a role, and possibly the combustion characteristics.
 
Originally Posted By: Cujet
There is no question that adding a bit of oil to gasoline can make certain engines run smoother. Even modern engines.



I don't think I'd do it if I had a catalyst to worry about, so that would tend to exclude modern engines, at least where emissions are tested.

If they aren't I suppose you could ignore or eliminate the catalyst.
 
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