This item can be returned in its original condition for a full refund or replacement within 30 days of receipt. The term heavy ends may be old fashioned and obsolete. Holley 804 fuel pressure regulator install - YouTube 0:00 / 5:58 Holley 804 fuel pressure regulator install Schnebs Garage 2.42K subscribers Join Subscribe 72 Share Save 15K views 3 years ago. Holley 12-804 Fuel Pressure Regulator Installation Instructions . 3 0 obj <>stream Call 800.979.0122, 7am-10pm, everyday. This regulator is used to adjust to fuel pressure requirements of various carburetors and supplies the proper pressure to the needle and seat valve to prevent flooding or drivability problems. Q: Depending what your compression is you could add 5% kerosene up to 25% for cars from the 20s with very low compression, like 5:1 or less. Adjustable fuel regulation from 1 to 4 psi, 1965 and older U.S. manufactured California Certified vehicles, 1967 and older U.S. manufactured Federally Certified vehicles, 1967 and older Foreign manufactured vehicle, 1966 and newer U.S. manufactured California Certified vehicles, 1968 and newer U.S. manufactured Federally Certified vehicles, 1968 and newer Foreign manufactured vehicle. The engine was running. Holley Carburetor Fuel Pressure Regulator 1 To 4 Psi Bottom Inlet Sides Are Outlets from Pacific Customs Unlimited your best source for Street, Off Road, Sandrail, Dune Buggy, Manx, Rock Crawler, Volksrod, or Mud Buggy VW Parts. The thinner, lighter products are at the light end of the scale the thicker heavier products are at heavy end. The check ball is held shut with the diaphragm and spring and once the desired fuel pressure builds up it opens that valve and allows fuel to go back to the tank. The Holley 12-804 fuel pressure regulator features 3/8" NPT in/out ports. 3/8 Inch NPT Ports 1 Inch 2 Out. Auto Parts v 6c02f45cd (2fvgn) cv1440. I have used kerosene to avoid vapor lock and there is no doubt it helps, the more the better up to 20% in a low compression 1920's car. One needs to have studied Chemistry as I have to actually know how this works. Shipping was fairly fast. In fractional distillation (the refining of oil) - what we call "mineral spirits", "paint thinner", "kerosene" and "diesel fuel" all ALL "heavier" hydrocarbons (pretty much in that order) than what we call gasoline - in that they occur lower in the distillation tower and condense at lower temperatures back into liquid before what we call "gasoline" does. $59.69 . Interesting theory. Another thing you can do is wire the fuel pump to be hot in run and start through an oil pressure switch - so if the motor shuts off or looses oil pressure the fuel pump shuts off too. Reasonable . I installed this on my Onan 7000 generator as part of a project to resolve vapor lock issues in hot weather and high altitudes. The 12-803 BP is a By-Pass design of the same style. I ordered the 12-804 regulator online because I couldn't find one locally, this is for an engine on a piece of equipment that I make my living with. #1 Holley 12-803 Fuel Pressure Regulator January 16, 2011, 11:41 AM Can it be mounted upside down (adjustment screw pointing down) and still work properly? Troubleshooting Carburetor Problems and Vaporlock Blues Revisited - Hagerty Lifestyle. [{"displayPrice":"$58.17","priceAmount":58.17,"currencySymbol":"$","integerValue":"58","decimalSeparator":".","fractionalValue":"17","symbolPosition":"left","hasSpace":false,"showFractionalPartIfEmpty":true,"offerListingId":"UhTnfcw7IZxaNntXlJwDKCZdMn2swwW9Qa8PxzrWBz%2By8RC0ilxVsHIj8toGUO%2FPmmF8b2HD1iNYooZ7n4ER0XuKiQsQQvJG86lgqsni6KYZs%2FdLcIOIE0Ukulbz%2BJYBuUOC820ciUZxU2UEL9sUjtoq8gdk8bOPIZ3QChg8zpgyIZxlTaXQEA%3D%3D","locale":"en-US","buyingOptionType":"NEW"}]. Of course you may already have this setup - that is the first issue. I am having problems understanding why you say OD is wrong and Rusty is correct, it seems to me you are all saying much the same and that is that gasoline is made up of many components each having different boiling points and the components with the lowest boiling point are the cause of vapour lock. Octane is an actual chemical which would be at the light end of the scale for gas, kerosene would be at the heavy end. Wouldn't the water still evaporate at the same temp? It's a diaphram with a spring. Holley 12-807 Fuel Pressure Regulator Diaphragm Repair Kit made by Holley, for as low as $9.21. Please try again later. By If I wait a hour for the system to cool to ambient temperature then it starts easy. I had hoped that the cooler fuel from the electric pump would solve the problem but it did not. Adding some additives can raise the AVERGE boiling point but cannot remove the lower-boiling components, so regardless of what higher ends are present, the initial boiling point will remain that of the most volatile components. Generally speaking if your car was made before 1953 it has low compression. There is no "chemistry set" method to measure fuel vapor points. te4cmCbGnt]&~`N@RPyBTa$=~fo:/T 92YE)3Uofo4Ou].-zowDt*ae^qf9z/?. Great feedback from a knowledgeable group, guys! fuel pressure in at the top, fuel pressure out on each side. Does it come with the hose fittings or to be bought separately? By the way, I had an excellent service from this seller (5 stars!). You can wire a by-pass switch for priming if it is really required. None of them worked. Click here to find a . In the fuel use map in the Exxon or Mobil gasoline websites, there are a few places where the Reid Vapor Pressure spec is varied from other fuels. The Holley 12-804 is a 1 to 4 range PSI regulator. Thanks to all contributors, particularly the information from Rusty, Bob and David. Too much fuel pressure for a given needle and seat assembly can overload the needle and seat and may cause flooding or drivability problems. 9517377223. Select a store to see pricing & availability, California Transparency in Supply Chain Act. Some of these items ship sooner than the others. Did not like having to reset to zerobut I did. Use with standard pump only - not recommended for maximum pressure pumps. Adjusting Holley & Demon Mixture Screws; Holley Specs HP Series; Edelbrock Carburetor Specs; Holley Double Pumper 4150 Specs; Carter Competition Series AFB Specs; Company Info. It is an experimental thing and MORE IS NOT BETTER - less is better until you find the happy medium based the fuel you buy or have in the tank already. 12-804 : Quantity: Share : . Show details From the manufacturer Can i install a fuel pressure guage on the unit itself? Holley 12-804 Carburetor Fuel Pressure Regulator 1 To 4 PSI Bottom Is Inlet Sides Are Outlets for a sandrail, rock Crawler, KOH, Ultra4, truck, UTV, side-by-side, dune buggy, mini buggy, manx, king of the hammers, 4x4, or Jeep. We tend to speak of pressure as higher or lower than atmospheric however it is a relative measure and pressure applies under all conditions. On the Holley 12-804 fuel pressure regulator, the factory preset is supposed to be 2.8 pounds - can anyone say is Holley usually pretty accurate on these presets? Will changing the orientation change the preset pressure setting (checkball falling instead of raising)? Copyright 2008-2023 OReilly Driving on a warm day in heavy stop start traffic it started vapor locking on a climb - using 10% ethanol fuel with no additive . If youre looking to dial it in accurately its not going to do it. If your having pressure controll issues with the Holley regulators you can eliminate most problems with stability by installing a by pass line back to the tank and usualy a street car can use 1/8 copper. We encountered an error while updating this page. The carburettor was flooding, the electric pump was still running. [endif]-->