August 26, 20178 yr I have an 85 Brat with a Weber Carb that won't start. I have replaced: Distributor cap Distributor rotor Fuel Pump Both Fuel Filters Spark plugs Spark plug wires The closest it ever got to starting was when I put carb cleaner in it. So maybe even though it has all new fuel parts it still isn't going to the carb? Any advice would be helpful.
August 26, 20178 yr put a timing light on it to see where it's at. then if it's too far off lift up disty and reset the rotor appropriately
August 27, 20178 yr If it fires after spraying carb cleaner in it, then my guess is that it is lacking fuel.
August 27, 20178 yr Author Ya that's what im thinking but the entire fuel setup is new. (Pump and filters) It does squirt fuel into the carb when i move the throttle wheel because I can see and hear it. Is it possible some stupid safety feature or something is not allowing the fuel pump to well...pump? The car will not come close to starting unless I put carb cleaner in it or if i pump the hell outta the gas pedal...
August 27, 20178 yr Author I have developed a theory. I read up things that could make it not get fuel correctly and stumbled upon the fuel pump control unit. The little black or grey box that is on top of the hood latch. In a related story my windshield leaks, which is something I will fix later. When I went to check out the FPCU it had water in and on it from the rain. This has to be it. Unfortunately there are expensive and hard to find online. So im gonna try and find one from a parts car. I will send a pic of it after work, but its a little black box with a Mitsubishi logo on it. Any idea what the part number is for it?
August 27, 20178 yr A way to see if the fuel pump is working / delivering fuel under pressure to the carb - take fuel delivery line off carb - turn key on to check this. or perhaps issues with float valve / needle jet setting. low fuel level in float bowl. Agree also the fact that it fired, spraying carb cleaner into in it, suggests issues with the fuel system, still, somewhere. but it could be as previously mentioned : basic ignition timing - rotor should be pointing at no 1 spark plug lead position on distributor cap with corresponding ignition timing marks lined up between 0 - 10 BTDC on flywheel seen in inspection hole ( by repositioning or rotating distributor - which ever is necessary) Roughly timed by hand like this it should start / run by rotating distributor back and forth slightly from this initial position. Agree - to use timing light to time accurately. (5-6 degrees BTDC for 87 fuel) Edited August 27, 20178 yr by subnz
August 27, 20178 yr Importantly was it running before weber went on, assuming this is what happened, if so would not be chasing timing unless you loosened off dizzy lock down bolt. Replace one lead at a time so not to screw it up? Firing order is not same as other fours as it is 1324.
August 27, 20178 yr Author I bought the car on Craigslist for 500 bucks. It wasn't running because of a bad carb, among other things. I might have screwed up the distributor timing at some point idk. Here's some pics of the Fuel pump control unit. It looks a little corroded on some points but if it got water damage I doubt I could fix it. https://ibb.co/cHhHz5 https://ibb.co/c0QRsQ https://ibb.co/m3wMRk https://ibb.co/kZc6sQ
August 27, 20178 yr There are aftermarket substitutes for the FPCU. http://www.ultimatesubaru.org/forum/topic/160932-revolution-sensorfpcuwill-this-work/ Check ebay for others. It is just a relay triggered by coil ignition pulses. Check the FPCU by checking for voltage at the pump w/cranking. You can hotwire the pump for testing purposes.
August 27, 20178 yr How do I hotwire it? Connect the ungrounded pump wire to battery positive thru a fuse and a switch. (You lose the safety feature of the pump stopping when the engine does.)
August 27, 20178 yr Author I probably am gonna see if I can get lucky first and find one at a junkyard. Are there any aftermarket ones on ebay or whatever?
August 28, 20178 yr I probably am gonna see if I can get lucky first and find one at a junkyard. Are there any aftermarket ones on ebay or whatever? https://www.amazon.com/Revolution-Electronics-Electric-Controller-Primes/dp/B00BNZ05JM
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