Dirtyowlnumber4 Posted February 7, 2018 Author Report Share Posted February 7, 2018 Leave the gas cap slightly loose and see if your problems go away. As to pressure build up in the tank where would it come from???? Only exhaust is under pressure. My jerry can always has a decent amount of pressure when I first open it could be because we have cold nights and warm days here. Tried it with the gas cap loose but still won't start right now. The spark plugs looked very clean today but there seemed to be a covering of oil on the piston heads. Don't know how that got there. Quote Link to comment
Dirtyowlnumber4 Posted February 7, 2018 Author Report Share Posted February 7, 2018 So yeah yesterday fired right up drove 10 miles with little issue, today with no changes tried to start it for an hour straight nothing happened. Cleaned the spark plugs afterwards, tried fiddling with the carburetor, tried a new cap on the distributor put some spark plug grease on the wires still nothing. Gotta go to work now but any more speculations would be appreciated. Quote Link to comment
racerx Posted February 7, 2018 Report Share Posted February 7, 2018 how many turns out did you do for the idle mixture? and what was your idle rpm? Quote Link to comment
Dirtyowlnumber4 Posted February 7, 2018 Author Report Share Posted February 7, 2018 the idle mixture usually runs well at about 1 turn out. idle rpm is 1000rpm can't get it any lower problem with the throttle linkage Quote Link to comment
datzenmike Posted February 8, 2018 Report Share Posted February 8, 2018 Depends how you clean a platinum or iridium plug. Normally they aren't cleaned but replaced. You can very easily fuck them up. Which brings me to what make of plug? Should be NGK for an A series. Quote Link to comment
Dirtyowlnumber4 Posted February 8, 2018 Author Report Share Posted February 8, 2018 they are ngk platinum. i clean them with a toothbrush 1 Quote Link to comment
datzenmike Posted February 8, 2018 Report Share Posted February 8, 2018 Again the tank should be vented to the charcoal canister which collects and saves the fumes. I had what I thought wa pressure in my 620 tank. Every time I refilled where was a huge whoosh. I ignored it until the gas tank imploded. Looked like a squashed banana. Quote Link to comment
Crashtd420 Posted February 8, 2018 Report Share Posted February 8, 2018 they are ngk platinum. i clean them with a toothbrush Maybe try the standard ngk plug for the motor... not the platinum.... On a different motor, not a datsun, my brother tried to put better plugs in and the motor started getting bad gas mileage and throwing codes.... he later found online that the motor didnt like the newer plugs for some reason.... he put some 3 dollar autolight plugs in and the motor ran perfect again.... might be worth the $10 to see.... Quote Link to comment
KELMO Posted February 8, 2018 Report Share Posted February 8, 2018 ^^^This, use the regular NGK plugs. An "A" motor requires nothing fancy. I will look later on today but I think BPR5ES or BPR6ES. Quote Link to comment
Dirtyowlnumber4 Posted February 8, 2018 Author Report Share Posted February 8, 2018 I will try some new plugs. Tried kajiggering my chinese carb on there to see if it changed anything but it appeared to have broken while sitting in the shed. Throttle doesn't work anymore. Starting to think it might not be a problem with the carburetor though. I was thinking maybe it is dying because the cylinders are flooding over time because the spark plugs aren't able to keep up, but I take the spark plugs out when it dies and there's no fuel in the cylinders.. Valves needed some adjustment which I couldn't do can't rotate the engine with my giant ass radiator in the way but they seemed to be working well enough. If I can get a second I will take the head off and look at the bottoms of them. Quote Link to comment
DIY 1985 Posted February 8, 2018 Report Share Posted February 8, 2018 How does you oil dipstick seal, as it fits in its tube, look? The crankcase needs to be closed for intake vacuum at this location. Perhaps oil is getting in from above the cylinder rings? 1 Quote Link to comment
KELMO Posted February 8, 2018 Report Share Posted February 8, 2018 NGK plugs 22401-W8915 (Nissan part #) BP5ES applies to the A14 motor. Where you have the electrical cover over the EGR port....have you sealed that or put a gasket in there? 1 Quote Link to comment
datzenmike Posted February 9, 2018 Report Share Posted February 9, 2018 How does you oil dipstick seal, as it fits in its tube, look? The crankcase needs to be closed for intake vacuum at this location. Perhaps oil is getting in from above the cylinder rings? It should be sealed so that any blow-by doesn't push any oil fog out and make a mess or smell. The crankcase isn't sealed anyway as there is a breather pipe from the valve cover to the air filter and there is the crankcase breather that connects to the PCV valve in the intake. 1 Quote Link to comment
Dirtyowlnumber4 Posted February 9, 2018 Author Report Share Posted February 9, 2018 How does you oil dipstick seal, as it fits in its tube, look? The crankcase needs to be closed for intake vacuum at this location. Perhaps oil is getting in from above the cylinder rings? Could be doing, the valves are old. I'll look at em. Not really sure how oil flows around an engine. All I know is that the rings are brand new and professionally installed so I dont think its coming from the bottom. NGK plugs 22401-W8915 (Nissan part #) BP5ES applies to the A14 motor. Where you have the electrical cover over the EGR port....have you sealed that or put a gasket in there? Yeah I don't have high temp gasket so I made a gasket from normal gasket material and wrapped it in tin foil it seems to be faring all right. 1 Quote Link to comment
DIY 1985 Posted February 9, 2018 Report Share Posted February 9, 2018 Under light throttle conditions, the PCV is closed to closed. It allows manifold vacuum to clear out bad gasses from the below the pinstons. If it is stuck open, prehaps because of intake backfire, it will possibly drink crankcase oil. You could probably inspect it's hose. The Z24 pcv was probably cleanable, but it costs less than a can of carb cleaner. It being stuck open is a kind of vacuum leak. 1 Quote Link to comment
datzenmike Posted February 9, 2018 Report Share Posted February 9, 2018 PCV works (is open) at all times there is vacuum. Technically a vacuum leak but the carb system is designed to allow for this. Any small leak can be tuned out by the idle mixture and idle speed screws. If curious, remove the PCV and shake it. The valve is held closed by a very weak spring. If it rattles it's presumed good. Suck on the manifold (vacuum) side and air should pass, blow into it and it should not pass air. The problem with it being open all the time, (stuck) is that it can't prevent a back fire flame going back down the rubber hose to the block vent and igniting any fumes there. Somewhat unlikely, but I did see a stalled and badly flooded early '60s car explode when I was a kid. It backfired and blew the valve cover and oil pan almost off. It's a one way valve. 1 Quote Link to comment
Dirtyowlnumber4 Posted February 10, 2018 Author Report Share Posted February 10, 2018 All right I'll have a look at that. Took off the head to see if the valves were screwy but besides a little oil in the exhaust valves everything looked fine. I found that the exhaust hookup to the EGR was rusted away so there is just a hole in the bottom of it I corked it we'll see how that holds up. I don't know what this thing is I thought it was supposed to be flat but turns out under all the carbon buildup there are ridges fancy that. Quote Link to comment
DIY 1985 Posted February 10, 2018 Report Share Posted February 10, 2018 In a pinch I'd, reach for aluminum foil. IMO, if you were to fab up a EGR delete plate, you could probably get a totally flat surface from a medium to thick aluminum frying pan, check for flatness using a straight-edge . Use a jig saw for the profile, and drill clearance holes starting with a center punch. I use a candle, or bees wax to keep cutting tools from loading-up with sap or soft metals. If the EGR delete-plate is kinda thick, it will resist changing shape when tightened or exposed to temperature changes. When time comes, just send it with the rest of the intake manifold to the bead blaster, then get them powder coated. Quote Link to comment
datzenmike Posted February 10, 2018 Report Share Posted February 10, 2018 This is pinched between the intake and the exhaust manifolds and MUST be sealed tightly or you will have a vacuum leak in the intake. It is heated from below by exhaust gasses and helps evaporate fuel dumped in from above by the carburetor. EGR uses exhaust. Exhaust has almost no free oxygen in it, basically it's inert and just takes up space in the cylinder. If the hose from the exhaust is rusted away outside air will get sucked in. Outside air contains 20% oxygen and will dilute and lean out fuel mixture whenever the EGR valve is activated. So, either fix that exhaust tube and run the EGR, or disconnect the EGR hose from the carb. This will deactivate it. You can remove the EGR valve but why? if deactivated it's doing nothing and removal means making a block off plate and gasket that may leak. Better to simply leave alone. Quote Link to comment
DIY 1985 Posted February 10, 2018 Report Share Posted February 10, 2018 His reasoning behind the EGR delete was for carb clearance. Quote Link to comment
datzenmike Posted February 10, 2018 Report Share Posted February 10, 2018 Then it must be completely sealed. I removed mine when I got rid of the co-joined intake and exhaust on my L20B. I switched to a '79 intake. This... To this...Same intake. Some grinding, some JB weld, some tapping to get the PCV valve working. There's no gasket to leak or bolts to come loose. Quote Link to comment
Dirtyowlnumber4 Posted February 10, 2018 Author Report Share Posted February 10, 2018 All right put the engine back together nothing changed wasn't expecting it too because I didn't really change anything. Starting to suspect it's an ignition problem I tightened up the boots on the dizzy to try and get better contact and it's been idling pretty happily for a few minutes now. Just seems like any excess amount of fuel overwhelms it and floods it for a while. I'll work on getting an electronic system set up before I complain anymore probably. Checked the pcv seemed alright it was letting a little air through when it was closed but not much at all. Wouldn't want my car to explode. I was thinking of just welding a cover to the top and bottom of the egr but don't have a shop to do it in unfortunately. Quote Link to comment
flatcat19 Posted February 11, 2018 Report Share Posted February 11, 2018 Not enough spark? Weak/fouled plugs? Think fuel? Fix ignition. Vice versa. Quote Link to comment
DIY 1985 Posted February 11, 2018 Report Share Posted February 11, 2018 Welding cast materials is sketchy. Cast metal lacks the tensile quality that allows for the expansion and contraction of the localized melting. It probably could be done, but, are you sure that the plate that you made isn't functioning. They may give you second rate service if you took your ride in to the mechanic with that plate, but I bet that it mostly functions. What are your main jet sizes? Air correctors? Idle jets? Was it an A14 kit? Maybe your are carbon fouling plugs with too much fuel causing weak spark, as suggested by the inability to cold choke? Quote Link to comment
Dirtyowlnumber4 Posted February 11, 2018 Author Report Share Posted February 11, 2018 Yeah seems like the spark is as strong as it was originally still not sure why it stopped functioning so abruptly. Check this out; -Giving the car a lot of gas it will hardly ever die -Idling it will die in a few minutes -If I am driving and I take my foot off the gas but leave the car in gear (like engine breaking I guess) that will make it explode then die in a few seconds. Getting new plugs we'll see how that goes over I think my plate is good but as I discovered the hole in the bottom of the EGR port is open. I corked it. with a cork. I'll keep my eye out for a big ol bolt I can screw in there Don't know what hoodickeys are what I'll figure it out. Don't have calipers either I have a ruler though. Someone told me I need high altitude jets. I believe it was an a14 kit https://www.piercemanifolds.com/product_p/K624.html Quote Link to comment
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