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I have a 1996 Nissan 240sx with the stock ka24de and i have been having a crank no start issue. I have spark at the plugs, good fuel pressure and good compression. The only thing remains is timing. How would I go about double checking the timing chain since the chain doesnt have the same markings as the fsm?
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Make your own marks (white out or a white marker of some kind)
It should have marks of some kind shouldnt it like a punch in the cam gears and the cylinder head and the crankshaft with the engine block
But if it doesnt make your own marks from the gears to the block and the head start by making sure NO.1 cylinder is TDC compression stroke then again i dont think it matters what stroke and spin it over TWICE and see if it lines up again
See if this helps.
http://s183.photobucket.com/user/ppctx/media/240sx/ka24deTimingChain-1.jpg.html
Good luck and keep us posted.
It look the same as the chains in that picture. on the way home I borrowed a timing light to see if #1 is firing right. Are there any sensors that could prevent it from starting? I had just done quite a bit of work to the car fixing the knock sensor, a new water pump, thermostat, radiator, front main seal and since it it hasnt beeen starting, I have replaced the crankshaft pulley (I noticed a crack in it when i was going to put it back on), cap and rotor, spark plugs and wires, and checked all of the fuses. the fuel pump is only a year old and when I take the spark plugs out, I can smell fuel. i have pushed the pedal to the floor to “clear the flood” and that didnt work either.
Good fuel pressure is one thing but I would also check the injectors have power, and a pulsing ground when cranking. You can do this with a test light. It’s unlikely you’ll find anything wrong given what you’ve said but worth ruling out and only takes 5 minutes with a helper.
Spark, fuel, compression and timing are the main causes of a crank-no start but so are intake and exhaust restrictions.
Do your best to keep things simple. Don’t assume it’s a sensor failure. Be sure to check for fuel delivery from the injectors with a noid light. You can sometimes use a test light for this but the noid lights work much better for this. You may be able to borrow one from your parts supplier.
http://www.jbtoolsales.com/sg-tool-aid-36300-noid-light-set/#oid=1002_1
Stay away from sensors and other theories until you have some proof that there’s an issue there. Check the basics first.
Good luck and keep us posted.
since it has been about 6 months since I ran a compression test, I decided to run one again. the results are as follow: (dry/wet)
1. 112/123
2. 115/124
3. 113/125
4. 115/126according to the FSM this car is supposed to be 179 + or – 14 with a min of 151.
the part I dont get, is they are so close together, but very low. granted this car hasnt been running for 3 weeks. another update, the timing light i was using broke, so I bought a new one for the one I borrowed and havent had a chance to check the timing. (it is hard to see the marks due to pulleys in the way of the pin.
two questions:
1. would this low of compression prevent starting? (it was running just fine before is just died pulling out of the garage)
2. what would cause all 4 cylinders to drop compression equally?I think it should start with low compression across all cylinders like that seeing its not to low (below 100 would be different story i think
Maybe engine wear? how many Kilometers/Miles has the engine got?
Could be piston rings or cylinder wall is worn or both but thats a engine rebuild
But it should still start it cant be to bad seeing its making some kind of compression
150,XXX, I have been maintaining it very well, oil changes every 4000 miles (mainly highway when I was commuting to schoool) i put 25,000 miles on it last year and the only issue was a bad alternator. The oldest filter is my k&n air filter (2 years) and I clean it every other oil change. it doesnt burn oil. if it does, 1/8th quart at most, but there is a small oil leak at the real seal (couple drops if it sits for a day). i work on my cars and a lot, but this is stumping my highschool auto class experience(3 years).
Did you have a fully charged battery and also did you hold the throttle open when you did the test? If not, either one of those can cause low readings.
The battery has been on a trickle chrage. its was reading 12.87 volts when I started. Since it was just me, i have the gas to the floor when i was cranking. should I put some electrical tape on some needle nose vice grips on the cable to hold the throttle open instead?
Sounds like you did it correctly. Nice job. I suppose we can believe the low readings now. The next step might be a leak down to find out where the compression is going.
I did a leak down test. they were all roughly 75% all of which was through the crank case. checked the radiator, exhaust, and intake with a direct line from the air compressor since the air flow was quite on the crankcase.
That being said, why is the leak down percentage so high when the engine is only 30% less than stock compression. also, would this amount of leak down prevent starting?
what are my options? just a fyi, the top end has been rebuilt and beefed up, so I would prefer not swaping out the engine. Cost is an important issue as well
The apparent mismatch between the compression test and the leakdown may be due to differences in the tests: cranking compression is a set of momentary squeezes which build up in the compression gauge line, while leakdown is more of a static test which allows more time for the air to escape where it shouldn’t. That said, your compression values don’t seem low enough to cause a no start. Did you ever check for injector pulse, or intake and exhaust restrictions?
The correct answer for your low compression would be a proper rebuild. However, I understand your concerns about the cost. I have resurrected an engine like yours quite quickly and cheaply by simply replacing the piston rings, lapping the valves and honing the bores, which were in good condition. This was done with the engine in situ.
Went to autozone to rent the injector pulse tester, it was already rented out. they are going to call me when it is returned. as for intake, i have removed everything up to the throttle body. and I could removed everything from the cat back if you think that will help. if anyone wants any pictures or videos, I can post them on here. Im getting tired of riding my motorcycle all the time (its still a bit cold out).
any ideas, ideas, advice, or anything at all is greatly appreciated. i just want to get this running again. i was planing on a fully rebuild, but i was going to buy another engine and take my time so I dont drain my bank accounts all at once and then swap it out after next winter
This no start article has tons of information on what to check and look for in a no start situation.
http://www.ericthecarguy.com/faq/solving-automotive-no-start-problems
Good luck.
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