Scgreen620 Posted June 9, 2014 Report Share Posted June 9, 2014 Not sure if this is the right place to post I am new ...I'm new to the datsun scene ... I have a 620 78 ... That is spraying oil out the air breather filter I just bought the truck and it doesn't seem normal to me it's not a lot of oil but I'm concern ...... it shoots out inside the hood drizzling the motor and other components plz help Quote Link to comment
ggzilla Posted June 9, 2014 Report Share Posted June 9, 2014 Its not normal. Hopefully its just the wrong breather. It should be inside the air cleaner. If you can see this breather it is not stock. Quote Link to comment
Scgreen620 Posted June 9, 2014 Author Report Share Posted June 9, 2014 I'll post pics tomorrow Quote Link to comment
wayno Posted June 9, 2014 Report Share Posted June 9, 2014 Has the block vent been plugged, the one that goes to the PCV valve? When you remove the oil filler cap while it is running, put your hand over the hole and slightly rev the engine, does it suck on your hand instead of blowing out? There is always blowby when the engine is idling. Quote Link to comment
Scgreen620 Posted June 9, 2014 Author Report Share Posted June 9, 2014 I don't think it's plugged it has a filter... that's where the oil comes out from .... Quote Link to comment
datzenmike Posted June 9, 2014 Report Share Posted June 9, 2014 Over filled with oil. Wrong dip stick and over filled with oil. Normal blow by will expel oil spray and fog out the breather. If oil level is normal then excessive blow by from a worn out engine that needs replacing or rebuilt. Quote Link to comment
Scgreen620 Posted June 9, 2014 Author Report Share Posted June 9, 2014 Well I don't think it's over filled .... I recently changed the oil ...I did the oil change and didn't have at least a quart of old oil ... That's when I just bought it ... It doesn't just spray oil it seems like it just blows drops when I floor it . I do check on the oil daily and I seems like it's not losing much .. Quote Link to comment
metalmonkey47 Posted June 9, 2014 Report Share Posted June 9, 2014 Do a compression test. Quote Link to comment
datzenmike Posted June 9, 2014 Report Share Posted June 9, 2014 Depends on how much oil is getting out. A small amount of fumes and a drop or two go a long way to 'wetting' the filter. It may be almost nothing or it may be dripping wet... I don't know. It may not blow smoke or 'burn' oil but it's possible that there is lots of combustion getting past the rings. These gasses have to get out of the crankcase somehow. If the volume is high enough the normal spray and fog of fine droplets of oil inside will be carried along with it. If the little filter on the valve cover is oily throw it away and connect it back up to the stock air filter. (I don't know why people mess with the PCV system so they can run those little blue things) If you notice excessive smoking afterwards... then blow-by is pumping oil into the carb and better to run the valve cover hose over to a catch can to collect the oil. 1 Quote Link to comment
Scgreen620 Posted June 10, 2014 Author Report Share Posted June 10, 2014 Doesn't the stock filter go on the carburetor filter itself ? The truck has a weber carb ... Is there another stock filter that I use? I was thinking of buying a k&n filter Quote Link to comment
wayno Posted June 10, 2014 Report Share Posted June 10, 2014 Doesn't the stock filter go on the carburetor filter itself ? The truck has a weber carb ... Is there another stock filter that I use? I was thinking of buying a k&n filter This is how the engine vent system works, there is a engine case/block vent on the side of the engine under the intake/exhaust manifolds, the tube is about 1 inch round, and on the L20b it is routed out just under the #4 exhaust outlet, that goes to the PCV valve screwed into the intake manifold just under the carb, this is a good setup and you want it on your engine, if it has been removed, it was removed by someone that doesn't know what they are doing, before the PCV people were lucky to get 100,000 miles out of an engine, since the PCV valve was put on engines, they get 300,000 miles or more all the time. The other vent is the valve cover vent, the reason that vent goes to the underside of the air filter is that it doesn't always blow out air, sometimes it sucks in air, so if it is connected to the air filter, then when the valve cover vent is sucking in air, it is filtered air, that is why it goes to the air filter, so it doesn't suck in dirt. Quote Link to comment
ggzilla Posted June 10, 2014 Report Share Posted June 10, 2014 A Weber filter is not a stock filter. The stock filter is large and round and inside the factory air cleaner. Few people use it with a Weber. In either case, the hose from top of valve cover should be connected to underside of air filter. Weber has provision for this. The round hole and the white fitting are used to connect the hose. Quote Link to comment
smoke Posted June 10, 2014 Report Share Posted June 10, 2014 sounds like a lot like a plugged pcv. Quote Link to comment
datzenmike Posted June 10, 2014 Report Share Posted June 10, 2014 The PCV doesn't draw that much air, after all it's a vacuum leak in the intake manifold. Just how much can it draw before affecting the running? It isn't enough to cause a vacuum in the crank case unless you put your thumb over the valve cover vent. Anything that comes out the vent under throttle is blow by. Too much volume and some oil is going to get pulled out along with it. Quote Link to comment
smoke Posted June 10, 2014 Report Share Posted June 10, 2014 I was thinking it wasn't really all that much he was dealing with. Quote Link to comment
ggzilla Posted June 10, 2014 Report Share Posted June 10, 2014 That's your idea of not really all that much? . it shoots out inside the hood drizzling the motor and other components plz help Quote Link to comment
wayno Posted June 10, 2014 Report Share Posted June 10, 2014 My old engine in the work truck had a lot of blow-by, if I removed the oil cap while the engine was running/idling and stood there for a couple minutes watching it run, I could look at the bottom of the hood and see a oily spot forming on the under side of the hood(a couple feet away from the valve cover hole), this is while the hood was up, but I had other issues also, like oil blowing through the gaskets/seals, the engine was wore out, I was going through about a gallon of oil a week, yes there was an oil spot where I parked it at night, but it was not a gallon of oil spot, that engine was burning a lot of oil. How much oil do I think it was actually burning you ask, if I added a quart of oil in the morning when the engine was cold, and then started it up, it would burn clean for a few seconds, then it would smoke up the whole area till it burned off the oil that got by the valve seals, if I added a lot of oil, it took longer for it to burn off. Quote Link to comment
ggzilla Posted June 10, 2014 Report Share Posted June 10, 2014 With the cap off, engine running, OHV engines don't leak much. But OHC like L16 will spray out a lot. With cap on, breather system working, no oil should leak out through filter. Overfill it or bad rings or stuck PCV, and oil gets everywhere. Quote Link to comment
Scgreen620 Posted June 11, 2014 Author Report Share Posted June 11, 2014 You guys are amazing ! the truck spits oil from the valve cover filter it's the little cone one....it might be installed wrong the weber carb doesn't have an air filter I have been looking online for just the filter but I can't find it .... I will check if it does have the Pcv valve Wayno the truck doesn't burn up a gallon a week minimum it's about a quart every 2 weeks ... But then again it might be bad lol Quote Link to comment
datzenmike Posted June 11, 2014 Report Share Posted June 11, 2014 Mileage. My 710 has used less than a 1/2 Qt of oil in over a year. It sits for 9 months of the year and I only drive it to Canby and back. Quote Link to comment
ggzilla Posted June 11, 2014 Report Share Posted June 11, 2014 Normal is less than 1qt/3000 miles Quote Link to comment
Scgreen620 Posted June 11, 2014 Author Report Share Posted June 11, 2014 Since we're talking about the engine how much did you guys pay to rebuild the engine ? I was thinking maybe in the proses maybe I can make the pistons bigger or something ... Any ideas? Quote Link to comment
wayno Posted June 11, 2014 Report Share Posted June 11, 2014 You are talking like that filter you are talking about is stock, like it belongs there, it doesn't belong there, it's likely some small tiny little filter that disperses the oil evenly everywhere, or it just constantly drips oil on the valve cover. Remove that filter, put a hose on that valve cover outlet that hangs down barely below the frame and call it good, or better yet, route it to a catch can, then route the catch can vent hose just below the frame. In the mean time start looking for a good L20b, or something cheap that you can rebuild on the side, then when it is ready, pull the wore out engine out, swap everything over to the new engine, install in your vehicle and drive it with a smile, knowing that you did it yourself. You guys are amazing !the truck spits oil from the valve cover filter it's the little cone one....it might be installed wrong the weber carb doesn't have an air filter I have been looking online for just the filter but I can't find it .... I will check if it does have the Pcv valveWayno the truck doesn't burn up a gallon a week minimum it's about a quart every 2 weeks ...But then again it might be bad lol 1 Quote Link to comment
Scgreen620 Posted June 12, 2014 Author Report Share Posted June 12, 2014 Clear as day thank you so macchh! Quote Link to comment
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