Just broke my MFI preheater hose

daepp · 08-02-2007, 10:17 AM

So as the subject suggests, I have just broken my pre-heater hose that runs from a connection at the sheetmetal to the MFI thermostat in my 72.

Temporarily I have duct taped the ends together. Is this ok, as I note that its a two piece hose?

Our host offers an inner and an outer hose. Is this for insulation purposes? The reason I ask is that there only appears to be a single walled connector at each end where the hose attaches.

304065 · 08-02-2007, 11:37 AM

It's for insulation. The two hoses keep the heat.

Duct tape is OK until both replacement hoses arrive. If the thermostat doesn't heat up the result is an excessively rich mixture, poor fuel mileage, washing of the cylinder walls with fuel resulting in increased wear and dilution of the oil with fuel. Grady posted that the fuel eventually replaces the oil making the level appear high, but once the engine gets hot enough to boil out the gasoline, the engine is left with no oil resulting in catatstrophe.

Can all that happen? Probably not in the time it takes for Wayne to ship you the hose, being that you're in SoCal. I wouldn't run my car for more than a few cold starts like that, however: Poor MFI is hard enough to keep in perfect tune, give the system and your MFI karma a break!

fireant911 · 08-02-2007, 01:43 PM

Quote:

Originally Posted by john_cramer

...the fuel eventually replaces the oil making the level appear high, but once the engine gets hot enough to boil out the gasoline, the engine is left with no oil resulting in catatstrophe....

Could someone substantiate this this actually occurs??? I realize that some fuel may get into the oil and contaminate the mixture but would this not thin out the mixture since both are petroleum based? I do not see that any boiling of the gasoline would occur, unlike moisture, since thinning of the oil would occur. The combination of water and oil is emulsive whereas oil and gasoline will freely mix. Please explain how this can be.