curious bystander
CCCUK Member
Perhaps somebody that understands this problem should do an article for Vette News to warn all those members who are oblivious to the potential hazard this stuff is causing?
Fuel consumption
- Thread starter Mad4slalom
- Start date
Daytona Vette
Well-known user
Ross you are on again
Daytona Vette
Well-known user
Ethanol has another issue for our V8s and I am trying to get my head round it correctly - to do with heat dissipation and the greater propensity for Fuel vaporization - getting old and forgetful
However we know it is a Solvent for Rubber and Plastics, but beware it also disintegrates something called; Fiberglass.
Ethanol Fuel goes off quicker in the tank - always keep the tank full so less air to decompose the Fuel, which would also add more water to the Fuel, especially when the car is standing for a month or so
BRING BACK LEADED!
However we know it is a Solvent for Rubber and Plastics, but beware it also disintegrates something called; Fiberglass.
Ethanol Fuel goes off quicker in the tank - always keep the tank full so less air to decompose the Fuel, which would also add more water to the Fuel, especially when the car is standing for a month or so
BRING BACK LEADED!
Daytona Vette
Well-known user
I am thinking of going over to a Pratt and Witney Turbine - The Aviation Industry do not allow allow Ethanol near their engines - I usually have to test my Vette on a Runway anyway!I think I am gonna convert my C3 to steam power . Maybe four cylinders and Walschaerts Valve gear . Then it can run on water all day long !
Roscobbc
Moderator
It's also linked with brake fluid. Dot 3 and Dot 4 mineral brake fluid has the same issue. Its hygroscopic also and will absorb moisture from condensation in the braking system. A major issue (as we all know) for earlier Vettes. The moisture also causes any cast steel/iron braking components to rust and contaminate the brake fluid just to make things even worse. The boiling point of the brake fluid is lowered by the moisture absorbed by the brake fluid - result is brake fade (and ultimately internal corrosion of the ferrous parts of the braking system).
Some believe that the use of Dot 5 silicon fluid is the answer. It certainly has a higher boiling point than other mineral brake fluids - so better for 'spirited' seat of pants driving and track day use. It isn't hygroscopic so doesn't absorb water..........good perhaps........but it does not prevent water getting in the braking system.
This time the water separates from the brake fluid in small gobules. Unfortunately in extreme conditions (i.e heavy and continuous braking) when the brake fluid temperature goes past the boiling point of water the gobules effectively turn to steam - once again causing brake fade.
There is only one sure fire answer - regularly change your old brake fluid for new (whether silicon or mineral)
Chuffer
CCCUK Member
According to a mate of mine with a pilots license , they don`t use WD40 either as that ultimately becomes hygroscopic with age after applied . Or something along those lines
Daytona Vette
Well-known user
Thank you Ross the water in Ethanol lowers the boiling temp of the Fuel and hence causes early vaporization - hot day, hot drive, switch the engine off and then a little later she does not want to start - one of our Members Chris, has built an Ethanol cooler for his C2 for precisely this problem - Genius!
Roscobbc
Moderator
I think our colleagues across the pond refer to this as 'percolation' - fine, except there isn't a cup of coffee as an end result.
Daytona Vette
Well-known user
Actually Ross it is called premature Vaporization (do not ask me how I know)
Daytona Vette
Well-known user
I have a heat shield between the Inlet Manifold and the Holley to stop the Vaporization and it worked well in the extreme heat of past summers, but as the Ethanol content has increased I can on hot days suffer with the Vaporization prematurely - after a hot run on a hot day, best open the Hood to let the under hood temp reduce quicker to stop / reduce the Vaporization - I do however have an under car spoiler at the front to direct more air through the Rad and two inlet Ducts at the front of the Hood to get more cool air into the under Hood area and Vents at the rear of the Hood for the hot air to flow out - Engine runs cool, just an ethanol issue.
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CaptainK
CCCUK Member
I was getting fuel vapourisation on my little 327 and it was causing driving issues and hot start issues. Driving wise I was losing power and it just didn't feel happy and hesitant to accelerate. Starting from hot was a bugger too. Chatted to a few people about it, as I didn't know at the time, and realised it was fuel vapourisation / percolation. Now I've fitted a phenolic spacer between my inlet manifold and the carb. Mine is only a thin one at about 0.4 of an inch thick - but it does the job really well. I needed a thin one due to bonnet clearance issues. In hindsight I could have gone thicker as I have a bit more space than I thought once everything was tightened down.
Now the car drives better, and I no longer hear the fuel bubbling away in the engine bay after I've stopped the engine. The carb itself is also MUCH cooler to the touch than before.
Now the car drives better, and I no longer hear the fuel bubbling away in the engine bay after I've stopped the engine. The carb itself is also MUCH cooler to the touch than before.
Daytona Vette
Well-known user
The issue increase as the rate of Ethanol in our fuel increases
CaptainK
CCCUK Member
True indeed. I try to stave it off by only using super unleaded too.
Chuffer
CCCUK Member
I think you will find that there 5% ethanol in our petrol now no matter what octane rating .
Chuffer
CCCUK Member
I read somewhere that Esso only sell Ethanol free petrol in a few areas of the UK . Absurd if you ask me ! Why not supply it to all their stations ? Probably all down to the logistics of where the refineries are located that omit the damned stuff !
CaptainK
CCCUK Member
Indeed. But in the future they are planning on upping normal unleaded to a lot more ethanol, whilst keeping the super unleaded at 5% as the protection grade. Could be worse though, in other countries they already have a far higher % of ethanol in their fuels.
sublimemike
Well-known user
From memory and the Mopar guys all Esso Synergy 97 octane is ethanol free though out England Wales EXCEPT for the South West. I will do some more digging and find the article