sotaorava Posted January 21, 2014 Share Posted January 21, 2014 Hi I tryied to find topics for this problem and found few but they did not help me... i have very hard time to crank the engine tryied 2 different batterys and 2 starters ground and + should be ok even plugs of engine turns hardly and + wire and starter gets very hot after trying. engine has never run just fresh rebuild n42 block 89mm bore 240sx pistons n42 head 1.2mm metal gasket is there any possibility that my timing chain could be to short i remember that it was very difficult to but on and that causes to much frigtion? bore is to tight? that means i have to take engine of can somesort head problems cause this?? Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted January 21, 2014 Share Posted January 21, 2014 Wires should not be getting hot. Did you modify or change any of the cars wiring or upgrade the alternator? Quote Link to comment Share on other sites More sharing options...
sotaorava Posted January 21, 2014 Author Share Posted January 21, 2014 alternator was upgraded before i swapped the engine was running good with my old l24 yeah wires getting hot would succest bad wiring or connection but main wires and connectors are new and i am running/testing starter directly from battery not by key... it turns like there is no power but battery is full 12.8v and tested another good battery also even with jumper cables so these should be enough power to turn the engine Quote Link to comment Share on other sites More sharing options...
TeemuM Posted January 21, 2014 Share Posted January 21, 2014 Have you cranked engine by hand? Did you assemble engine by yourself, so was crankshaft rotating freely when it was torqued? Quote Link to comment Share on other sites More sharing options...
sotaorava Posted January 21, 2014 Author Share Posted January 21, 2014 only thing i can think of is that i accidentally put oversize bearings in... could that make it turning hard? Quote Link to comment Share on other sites More sharing options...
rally Posted January 21, 2014 Share Posted January 21, 2014 Yes It locks crankshaft Quote Link to comment Share on other sites More sharing options...
AZGhost623 Posted January 23, 2014 Share Posted January 23, 2014 You might need a high compression starter... i needed one with my new motor the stock motor just wouldnt cut it. Quote Link to comment Share on other sites More sharing options...
Sam280Z Posted January 23, 2014 Share Posted January 23, 2014 Take out the spark plugs so that there wll be no compression. Try to turn the motor over by hand (wrench on the crankshaft pully bolt). It should turn easily. If you put the wrong bearings in, you will have to disassemble and replace them with the correct ones. Quote Link to comment Share on other sites More sharing options...
NewZed Posted January 23, 2014 Share Posted January 23, 2014 Pretty sure that the bearings can be replaced from below, engine in car, with some ingenuity. Here's an old link for example - http://forums.hybridz.org/topic/81528-replacing-piston-rings-with-the-engine-in-the-vehicle-l-series-faq/ Somewhere out there he describes the process in detail. He did not remove the engine. I think that the hardest part is getting the oil pan off. You could also try putting the car in high car (if it's a manual) and giving the car a shove to see how tight things are. Maybe it just needs a few spins to get lubed up. Quote Link to comment Share on other sites More sharing options...
Xnke Posted January 23, 2014 Share Posted January 23, 2014 If you installed oversized bearings on a standard size crank, it's possible you've ruined the main bearing caps IF you managed to seat them and torque them to spec. Same with the connecting rods...wrong bearings will distort the big end of the rods. If you didn't use assembly lubricant when you put it together...well... Quote Link to comment Share on other sites More sharing options...
Lazeum Posted January 23, 2014 Share Posted January 23, 2014 Your comment about timing chain being very tight is suspicious also. Tension should come from tensioner, so it shouldn't be tighter than any other engine. Regarding bearings, haven't you or the engine builder checked clearances during the build? That's clearly one of the major item to control during rebuild. Either builder did not know what he was doing or you should be fine. I would suggest to turn by hand the engine with spark plugs removed as suggested below to feel rotating torque of the engine. That would help you to remove engine block from the equation. Quote Link to comment Share on other sites More sharing options...
sotaorava Posted January 23, 2014 Author Share Posted January 23, 2014 ok engine is off and pistons are off you can turn the crank quite easily by two fingers...so i believe main bearings are ok i didnt find any markings from conrod bearings and they look good Quote Link to comment Share on other sites More sharing options...
ttodhunter Posted January 23, 2014 Share Posted January 23, 2014 Does the cam rotate fairly easily? The "How to Rebuild" book says that the cam towers are "align bored" and that if you remove the towers, they may not line up correctly after re-installation... Is there a possibility that the cam was in the wrong orientation when installed and the piston was pushing against an open valve? Quote Link to comment Share on other sites More sharing options...
Lazeum Posted January 23, 2014 Share Posted January 23, 2014 What about piston rings? Were they gapped correctly? (if too tight, engine once hot would be damaged but I don't know if you have run it before) Have you tried to turn the cranshaft before disassembling everything? How was it? Quote Link to comment Share on other sites More sharing options...
sotaorava Posted January 25, 2014 Author Share Posted January 25, 2014 how much is good piston ring cap? i found in one build that top ring should be 0,44mm and second ring 0,36mm is that ok? Quote Link to comment Share on other sites More sharing options...
Lazeum Posted January 25, 2014 Share Posted January 25, 2014 That's about right for stock pistons & rpm range. Quote Link to comment Share on other sites More sharing options...
sotaorava Posted January 25, 2014 Author Share Posted January 25, 2014 ok piston ring cap is ok little bit higher than that but atleast they are not causing the problem... Quote Link to comment Share on other sites More sharing options...
NewZed Posted January 25, 2014 Share Posted January 25, 2014 Maybe the problem is in the transmission. You never said if you tried to turn it by hand, but since the engine is out it should be easy enough to remove the transmission and give the engine a spin by hand. If the transmission is still attached do a before and after test. Quote Link to comment Share on other sites More sharing options...
sotaorava Posted January 25, 2014 Author Share Posted January 25, 2014 transmission should be ok...gear was free when tested. i believe problem was conrod bearings all should have been standart but there was some quality and size differences between the bearings Quote Link to comment Share on other sites More sharing options...
sotaorava Posted January 30, 2014 Author Share Posted January 30, 2014 Ok update i took piston rings off and put pistons and conrods back and torquet everything to spec...smooth and easy to turn piston ring cap is ok tho upper about 0.45 to 0.5mm second about 0.55 to 0.6mm dont understand how they could cause so much frigtion that my old l24 is easier to turn even with head and plugs in Quote Link to comment Share on other sites More sharing options...
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