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b18b1 Cranks, but won't start


dannwo1

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For the last month or so I was helping my buddy rebuild his b18 after he spun a few bearings. We got it all together and dropped it back in the car, but when it came time to start it we were dissapointed when we just heard the engine cranking and not starting. I've rebuilt/swapped alot of engines in the past so I pretty much expected some problems at this point.

From there I double checked the mechanical timing thinking we might have jumped a tooth or two with the belt during cranking, but the marks were still dead on.

 

After that I took a timing light to the harmonic balancer (after jumping the service plug) and noticed the timing was way off. Keep in mind the motor isn't running at this point so the light was blinking intermittently, nonetheless, it was enough (in the dark) to line up the red mark with the indicator on the timing cover.

 

{A peculiar situation was that the distributer was nearly bottomed out advanced to line up the ignition mark.}

 

When that yielded no results we double checked the plugs.They were all getting a very bright snapping spark.

 

I then hooked up a compression tester to see if there might be a problem with the valve seats or piston rings (all of wich are brand new). The readings from cilinders 1-4 were: 180, 178, 172, 180. Given a 25psi dievience threshold and a service limit near 130 along with the fact that the engine is cold (like 18 degrees lol) and the rings haven't yet been seated these numbers are fine.

 

Earlier today I turned to the fuel supply. The injectors were reused, but still work fine. When I removed the plugs to do the compression test they all distinctly smelled like gas wich means all injectors are firing. The fuel filter is brand new.

 

{A peculiar situation was that gas merely dribbled out of the banjo bolt on top of the fuel filter when it was loosened even when the key is in the auxillary position and when it is cycled} I had expected gas to spray out with much more force than that. Tomorrow I will test fuel pressure and post the results.

 

At this point we became desperate and I began to slowly turn the distributer while my buddy cranked the engine to see if I coud find a "sweet spot" using the old school method (with the service port jumped). Doing this we've managed to get the engine to stammer over a few revolutions, but it never ran for more than a half of a second. I eventually gave up and moved it back to the recommended position using the marks i've made earlier.

 

There are no fuses blown and both the main and fuel relays are clicking on and off. There are presently no DTC's stored.

 

We've also cleaned all existing factory ground connections and have added three more. One to the exhaust manifold, one to the valve cover and one to the thermostat housing.

 

So everything's there. Spark, fuel, compression, timing (ignition and mechanicall) New plugs/wires/cap/rotor/fuel filter. There must be something vehicle specific i must have overlooked so I decided to post my problem in this forum in hope that one of you guys or girls can chime in with some suggestions. I've tried to be as discriptive as possible to avoid confusion as to what has already been replaced/checked, but if you have any additional questions don't hesitate to ask.

 

Thanks in advance.

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you didn't mill the head or block?

 

you cant check mech timing (timing light) without the motor running... in theory you can but ive tried it and it never EVER worked out. but for what i can tell from everything, since fuel seems good (should spray alil more but still should half ass start) and messing with timing almost changed something id say you are either a few teeth off or somehow are at tdc and should be at btdc or something of that sort.

 

Possibly a bad fuel regulator or the thermostat ground (i know you checked this but still its a super common problem)

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The head is a new reman. unit and the block was bored honed and decked. All bearings and crank are new, as are the pistons/rings. I reused the connecting rods.

 

Timing's prob. a few teeth off. All the motors I rebuilt spin clockwise so when I did it I didn't give the rotation a second thought. Turns out alot of guys do this, so I don't feel as bad. LOL I'm checking it out in a few .

 

Yeah, I figured no matter where the distributer is the engine should at least start but run like crap.

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unless its sparking before the piston reaches tdc OR the valve are open... decking the block and head i think makes it almost a full tooth off by its self... then you go a few more by accident (loose tension or something) and it wont fire up.

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gas should spray out the fuel system when key is ON. not dribble.

 

make sure you have silence , turn the key to ON and listen to hear if the fuel pump comes on for 3 seconds. im assuming it wont.

 

make sure the ground from the engine harness to the thermo housing is clean and grounded well.

 

there is no need for all those grounds you have installed. specially one on the exhaust manifold. remove them all. all you need is the ground from the tranny bracket on top of the tranny to the chassis. clean metal to metal 4gauge wire ground.

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