ari falco

I am sure that the noise comes from the engine itself, inside the engine and not from an external source.(sounds like valvenoise) My thought is that the cam/crank/valve timing is not as it should , the chain and cam sprocket are at #2 hole , (factory setting) , I also tested with # 1 and # 3 on but with the same result . I just mean that if you remove/shave between 0.050in / 0.078in in total from block/head must have some negative effect on crank/cam/valve timing,,, OR ??? The relationship between camshaft and crankshaft must be affected by the overshaved/milled head/block , (and logic says that the chain tensioner can not make up for the distance lost ). ok...thats my theory...maybe i'm totally wrong

I have tried everything , but not a thicker gasket. I have chain slack whatever i do , it doesn't matter what mark i use on cam sprocket or how much i tightening the chain ,(there is a rattling noise) , but ONLY when i release gaspedal and keep the pedal on cruise mode , like something is loosening when i relese of gaspedal. I beleave that the cam/crank timing is not where it should bee due to over shaving/milling , i can however make it stopp rattling if i turn the distributor in diferent positions , but then i dont have any power in engine or it pings like crazy. crank bearings , pistons and rings, valves and sealings , camshaft , timing chain kit are all new.

Well ...after a good history search on my engine ,(z24 , straight-four , carburetor, 8 valve , sohc , breaker point ignition , 4 plug) , one thing is clear. The head and block have been shaved/milled too much , the head has probably,( i do not know for sure), been milled at least 0.030in(0.76mm) and the block at least 0.010in(0.25mm) , as you understand i cant get the engine to work as is should , the engine starts and runs but not as it should. Question is : does it help if i put a thicker head gasket ?? , i found one in Mexico,(ebay) for sale thats 2mm , (0.078 inch). (https://www.ebay.com/itm/HEAD-GASKET-THICKER-THAN-NORMAL-FITS-NISSAN-ENGINE-Z24-/253218371187). Or maybe a normal gasket with shim/spacer ?? ANY IDEAS ???

Hi Mike !! z24 , 4 plug , carburated . The cylinder head and/ block surface have been resurfaced below factory limits , Is it possible to restore the valve train geometry with head spacer shim ? , And if so, which solution is best ! copper/steel gasket closest block surface and the usual gasket on top, and use of sealant ??

I've tried all that....(i have the 4 plug engine)...the only thing that remains is the head...according to nissan spec resurfacing limit is 0.2 mm ,(0.008 in)..both the cylinder block and head..0.1mm block...0.1mm head...after resurfacing the head 5 times and the block 2 times i think the limit is passed long ago,,,time to look for another head....

The problem with the engine and the noise is probably , (99.9 %) , that the cylinder head was milled down/resurfaced too many times. I spoke with the former owner and was told that the cylinder head was resurfaced at least 3 times in his possession ,(and 2 times in my possession), it explains the problem. I will of course buy another cylinder head, Used obviously because new is too expensive, but how will I know that this cylinder head does not have the same problem ?. Is there a Resurfacing limit point where you can see if the head has reached its limits ??

Hi Mike !! My problem with the z24 persist and driving me crazy..!! I have not had much time to explore more what might be the problem,, but here it is : Nissan hardbody, 4x4 , z24 carburated , 1990 , valve lash OK!, The carburetor is ok!, No vacuum leaks,single spark , new timing chain and tensioner , (double row chain). New pistons, new cylinder head and gasket ,(AGAIN...) !! I hear a rattling sound from the engine between gear changes or when I ease on the throttle, it sounds only when the accelerator pedal is in some kind of intermediate position, not in pull or engine braking mode , and Always after 2000 rpm. (ignition seems to be ok, have not checked with a timing light) If I screw the distributor to the end against the engine the rattling stops , but then, the engine has less power and low rpm on idle , and when i connect the vacuum to the dizzy it starts rattling again. If I screw distributor to the end of opposite direction,(from the engine), increases the rattling noise but with a normal motor power and normal idle speed. In any case, it sounds only when I have the accelerator in an intermediate position, not under load. can it be that the compression in one of the cylinders is not as it should be? Sparkplugs ??,, ignition coil ??....i don't know what more to think of .. :(

https://www.flickr.com/photos/144233655@N04/27847398550/in/dateposted/ I have searched everywhere but can not find anything about it . oil out of the hole or not. hole appears larger than the entrance hole for the oil, how will the tensioner hold pressure if the oil comes out of the other end

Hi !! I have the same tensioner as in the picture here. The picture shows the entrance hole for oil, but there is one more hole on the top. Is that some kind of relief valve/hole ?? , because when i press in the tensioner it comes oil out of hole .

I went to my nissan dealer today , asking the mechanic to listen to the engine when revving it up to the point when it rattles/knocking , he was 100 % sure that the noise was from the valves. I checked the valve clearence and they are according to spec. The cam/chain alignment does not seem to be right , I do not know how important it is for the engine to function properly and that may be why I have noise in the engine and that I can not get the timing / idle right. I put the nr 1 piston at TDC and took some pics of the sprocket and chain , it seems fuc... up , the links and position dont seem to be as described in the manual . The strange thing is that the car has worked for a year, but with rattling / knocking in the engine, and without idle speed and ignition timing set satisfactory. The mechanic who did the job on the engine says it does not matter so much where the marks and links end on camsprocket. He insists that the ignition timing is correct. I will however replace the timing chain my self this time and according to the manual , There is enough material in this forum to do it my self. Sending pics from camsprocket/chain : https://www.flickr.com/photos/144233655@N04/ PS: the nr 1 piston is att TDC when i took pics.

Hi !! Grateful for all the help I received, thank you so much !! (my engine problems persist though )

Hi everybody !! I take a chance to ask you in here as a last resort before I sell my junk car. I am the owner of a 1987 Nissan 4x4 d21 z24 carbureted. First of all, the engine has been completely rebuild, new pistons and everything related to that , new head and gasket , new valves , and new timingchain/kit. , etc etc..... I swapped out the old carburetor with a much better , (rebuild one). The problem from the beginning was that the engine could not stay idle, at least not at 8-900 rpm as it should. at 1000 rpm and above idles fine. And from the begining i had this rattling noise from the engine , not at startup , but when i release the gaspedal after acceleration and kept the gaspedal in the midrange . no specific rpm. When i accelerate and braking with engine no rattling noise , only with gaspedal in midrange, (sounds like a dieselengine). The first time at the workshop they said its the timechain....Since then, the timingchain and tensioner has been changed three times,(within a year and a half), with no result. BUT !!!!.. I tried myself to set the advance by rotate the distributor , at some point the idle went up but the rattling got worse , (not at idle but when i gave the engine some rpm). I tryed the other way and the idle went down to allmost dead , BUT NO NOISE AT ALL....purring like a cat. I took a test drive and discovered that the engine had no power at all , and no noise at all !! I live in Greece and I believe that these so-called mechanics just steal my money , i'm fed up with this car , it has become a nightmare. Has anybody a clue on what the problem is ???? PS: sorry for my bad english

Hi !! ,...and thank you for the response. the only thing that is related to to the vacuum system on my car is the vacuum advance ,(that hose is connected and fine), and the bcdd . Sending links to photos...dont know how to post photos in here... :) bcdd vacuum :https://photos.google.com/photo/AF1QipP34R4wEzRuu6TQBAjZV3gjcoQwpyh7D0Zb4PfC advance vacuum :https://photos.google.com/photo/AF1QipNLk-Y8oZfyw4xLuq3NnFLrcqUQFxcorKWVr8ci ps : I suspect that the vacuum hose from bcdd goes to the air cleaner box.