Holley 12-804 1-4 Psi Carbureted Two Port Fuel Pressure Regulator: Item #: HLY12-804 : Quantity: Price: $53.99 Add to cart . This diaphragm repair kit is for 12-803 and 12-804 regulators. use a 1/16 - 1/8" restrictor in the end of your fuel line to see if you can set the pressure then. bowls after each run, just to see exactly at what temperature the problems become apparent. Yes, you will need to buy the type of connection you want to use such as hose barb, compre. readings of the carb. and a rotary click style one here on the shelf pete, you are welcome to borrow them to troubleshoot your problem.. let me Know. Show details From the manufacturer So this thread has been a great find for me particularly at this time. Neither the Holley instructions nor anywhere I can find says what the maximum inlet PSI should be allowed to the regulator - but I was told it was 16 psi and one other spot on the web says something similar. Interesting theory. Holley(R) has been the undisputed leader in fuel systems for over 100 years. When it burns however, it is an eye and throat irritant, even though it raises octane, burns hotter, easier, and cleaner. Holley 12-804 Holley Fuel Pressure Regulators JEGS 41040 JEGS Fuel Pressure Gauges Now you need fittings. The higher the RVP, the greater the tendency to vaporize or vapor lock. If so how? Interesting that the writer suggests certain additives can raise boiling point of gas in the first section. Rusty, thanks so much for this information. Sign up for a new account in our community. The BP article does not address how to re-blend your own fuel, and indeed - each batch of gasoline - and even how long it has been sitting in a tank will change it's properties as certain things evaporate out of the fuel changing it's properties if in a vented tank. The first opportunity to try it occurred recently. Fuel Pressure Regulators Instruction Sheet (42712804), Designed to be used with standard pump only, Measures 2-1/2" wide and 1-1/2" tall and deep, This low pressure fuel regulator is factory-set to 2.7 PSI, but is fully adjustable from 1 to 4 PSI, It includes mounting bracket with 2 each self-tapping screws for regulator to bracket installation purposes and 3 screws for bracket to vehicle installation, 1-3/4" hole spacing to mount the regulator to the bracket. I mix Industrial Maintenance Coating Thinner (IMCT) around 1 oz per gallon - which is basically a blend of petroleum distillate in the paint thinner / mineral spirits (once called also "white gas") family and ethyl acetate and not only does it cure vapor lock it increases octane because you can feel it in the power and acceleration. the fuel pressure gage needs to be in the line going to carbs. Much of the excess engine heat will end up soaking the fuel system under the hood. Can you adjust the fuel pressure? Shipping cost, delivery date, and order total (including tax) shown at checkout. . Never had it act up while running, but since E10 fuel came along it is borderline getting started after hot shutdowns. Holley low pressure reg woes #12-804. Log In / Register Order Status. For more information go to www.P65Warnings.ca.gov. So if you're looking for a FPR to get 1-4 psi, then the 12-804 is no longer your best choice. Sorry, we were unable to perform your search at this time. 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. Bobburns thank you for the confirmation and technical explanation. 100% Satisfaction Guaranteed CBPN804A Swinging Drawbar Pin Kit Ford NAA 501 600 700 800 900 2000 3000 4000 satisfaction guarantee the daily low price westernnorthndc.org, US $11.9 3000 501 Also services earlier models (1953 to 1964) using swinging drawbar: NAA 600 For Ford Tractors 2000 4000 (1965 and up) Jubilee . There are two kinds and they look the same. . Check the status of your Thanks to all contributors, particularly the information from Rusty, Bob and David. Might have been along the same lines as adding a quart of atf to the engine oil to help quiet noisy hydraulic valve lifters, or for "sludge clean-up" activities? Just open the hood and let things cool. If you have it plumbed up "dead headed", lowering the pressure might not react very quickly. Gauge looks small..it is not. MFG. . Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising. Decrease pressure by turning the adjustment screw counter-clockwise. Plain WATER has great cooling properties, but under pressure will boil at a lower temperature than anti-freeze mixed with water - up to a certain point. Most regulators need to be flowing to set pressure. Needs you to make/tap your own threads for screws, Reviewed in the United States on February 4, 2023. 3/8Inch Npt Ports 1 Inch 2 Out. Includes initial monthly payment and selected options. No issues. Troubleshooting Carburetor Problems and Vaporlock Blues Revisited - Hagerty Lifestyle. As Raywith pointed out, you need to let the pressure go somewhere. My bypass line has a shut-off valve that I can use to manually adjust the pressure, but when air bubbles develop within the input fuel line, this valve requires adjustment to maintain the fuel pressure. 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. Sorry, you're using a web browser that is no longer supported. Too much fuel pressure for a given needle and seat assembly can overload the needle and seat and may cause flooding or drivability problems. Holley 12-804 Fuel Pressure Regulator 3/8 pipe thread ports 7/32 restriction Pressure ranges from 1 to 4 PSI Includes mounting bracket Satin finish 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. Can anyone speak to the validity of this or is anyone currently using an additive for this? here's one installed,same holley low pressure regulator, line pressure in the top, one side is hooked to the fuel pressure sender, other to the line going to the fuel block. $41.19. Reviewed in the United States on January 15, 2021. Terms of Service. Reviewed in the United States on June 5, 2022. Refining of oil is basically heating it into vapors and then capturing those vapors various degrees of cooling - at the top is "propane" - at the bottom is "pitch" or "road or roof tar". It is not all the same. I have largely eliminated this problem with all fuel system components rebuilt, and an electric fuel pump but will get occasional stumble with a hot (after say, an hour run) engine idling or in traffic if it is say, 80 or hotter out. I have heard true lead (LeadMax2000 or simillar) may do this as well? I now think that what was happening was that there was sufficient heat in the carburettor to boil the fuel, the vapor from the boiling increased the pressure above the float preventing it from rising and shutting off the supply. The carburettor was flooding, the electric pump was still running. We will have the previous answer corrected. It is not intended to be sold or used for any other purpose. To see our price, add these items to your cart. Otherwise it's good. I have found IMCT is a happy medium that does both in the right quantities - raise boiling point and octane just enough to be a "goldie-locks" kind of additive to help prevent vapor lock. holley blue fuelpump pressure erratic. Holley 12-804 Fuel Pressure Regulator Brand: Holley 415 ratings -11% $6614 Was: $73.94 3/8" pipe thread ports 7/32" restriction Pressure ranges from 1 to 4 PSI Includes mounting bracket Satin finish See more product details + + Total price: $115.81 Add all three to Cart These items are shipped from and sold by different sellers. I have the one I have set up in a deadhead setup. There is no "chemistry set" method to measure fuel vapor points. Holley 12-804 Fuel Pressure Regulator Installation Instructions . Please try again. IMCT is found in the paint isle of any hardware or home improvement store usually in quart or gallon cans. The pressure regulator works fine when mounted flat, but should work ok when mounted on it. This Holley universal low pressure fuel regulator is factory-set to 2.7 PSI, but is fully adjustable from 1 to 4 PSI. But it is not the ethyl acetate alone that causes the effect to raise the vapor temperature point of fuel. If youre looking to dial it in accurately its not going to do it. Holley Fuel Pressure Regulators 12-803 HLY-12-803. I suspect as the article suggests even with all these steps you can still get the crap gas to boil if it is hot enough under the hood. All Holley regulators are pre-set at the factory so there is no guesswork when first installing the regulator. I think we have hijacked Steve's thread where he asked the question about raising the boiling point of gas which hopefully has been fully answered by these side issues. Wont be good for a finicky carb. We encountered an error while updating this page. This is another vexing problem with Ethanol mix, which is about all you can get here in CT. Our payment security system encrypts your information during transmission. Holley 12-804 low pressure regulator, Weber, jeep etc. Too much fuel pressure for a given needle and seat assembly can overload the needle and seat and may cause flooding or drivability problems. But the heavier elements will raise the boiling point of the mixture. 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. Learn more about our 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. Once these chemicals are blended - the over-all resulting chemical properties - especially boiling point under pressure is changed - they are NO LONGER SEPARATE boiling points in play. From that time on octane ratings slowly rose, helped by the addition of more and more tetraethyl lead. Holley Manufacturer Part Number 12-804 Manufacturer Holley Assembled Product Dimensions (L x W x H) 3.50 x 3.50 x 2.50 Inches Warranty Warranty information 90 DAY REPLACEMENT IF DEFECTIVE Warnings Warning Text proposition 65 reasons:titanium dioxide, other chemicals WARNING - California Proposition 65 None Report incorrect product information . ***The inlet pressure limitation is 7 psi. It is as said - of the "paint thinner" family in weight with ehtyl acetate blended in to make it's solvency properties a little "hotter " and stronger. Estimated Ship Date: Today. P/N 12-803, 12-501, 12-804, 12-500, & 15812NOS Installation Instructions WARNING! Purchased the regulator from Baxter, unit arrived in 4 days.. Everything does just fine, until temperatures rise above 80 degrees or so, as they are soon to do. $5 Off Your $100 Mobile App Purchase . You can do a Google search for it, though. I realize this is an old post - but when people write things that are WRONG - it leaves the next Joe who comes along thinking that is the correct answer when especially in this case - it is NOT. If I could get 75-85 octane, non-ethanol, Regular gasoline that vaporized at above 180 deg F, I think my car would run fine all the time. There is no hard and fast cutoff for any of these. ***The inlet pressure limitation is 7 psi. Try it, I think you will find it works. Did not like having to reset to zerobut I did. Please try again. Adjustable from 1 to 4 PSI.