civic vx: ignition timing/cam + crank positions

[dlb]

*EDIT* i was totally wrong on this. the 3 marks shown in the first pic are not TDC. they actually indicate 10, 15, and 20* BTDC. there is a fourth mark that should be an inch or so to the right of those three which indicates TDC. i could not see it on the crank though so i went and pulled the crank pulley, timing covers, and timing belt...all for nothing! once i found (and cleaned out and painted) the TDC mark, reassembled everything, and set the crank to TDC, i found that both the cam and crank were properly set.

so there you go, hopefully someone else learns from my mistake.*EDIT*


i bought a vx a few months ago. just finished replacing the input shaft bearing, some transmission seals, the clutch kit, front brakes, and radiator. took it for a test drive and it was pretty darn good but when my wife drove it, she noted a slight stumble sometimes. i remembered that i had checked the timing when we first got it and noticed it was quite retarded, even after i advanced it as far as the dizzy would go. in my focus on getting the input shaft bearing done, i had forgotten about this.

so today i loosened plugs #2-4, removed #1, shined a flashlight in the hole while i turned the crank counter clockwise, and stopped when i got to TDC of #1's compression stroke. here are the marks on the crank pulley lined up with the pointers of the lower timing cover to confirm this.



looked at the cam pulley and sure enough, someone has installed the timing belt incorrectly.



while it looks nice to have the cam pulley nice and even, with the 'up' right at the top, that's not the right way. on the vx, the lines on the pulley that sit opposite to each other are supposed to line up with the pointers on the timing cover. you can see that these ones are one tooth off.





being that this is an interference engine, whoever did this job is dang lucky they were close enough that they didn't end up trashing the whole engine.

i'm off to pull the lower timing cover and get this sorted out now.

[Rusty94cx]

The 3 lines on the crank are 10 15 and 20 deg timing marks line uP the cam and check you have a lone TDC mark.

[Rusty94cx]

http://static.flickr.com/40/93311660_dd7b15151a.jpg

That is TDC.

[dlb]

dang it, you beat me to it! i figured this out only once i had adjusted the belt and put the lower timing cover and crank pulley back on: that the cam pulley was not off, but i assumed that the only marks i could see—the 10/15/20* BTDC marks—were the TDC marks! i'm used to timing old toyotas, which are a very different and much more straightforward can of worms.

so i spent half a day pulling the timing belt off essentially just to find and clearly paint all four timing marks. it wasn't a total loss though, as i could then time the car accurately. i also learned how to change a timing belt, and use rope in the combustion chamber to remove a tough crank pulley bolt.

i'll edit my first post so no one makes the same mistake as me.

[Rusty94cx]

Rope? Humm big impact or use a flat screwdriver to hold crank with starter removed.

[dlb]

i work outside and don't have a big impact gun (just a 7.5 amp electric one, which was useless on this), and worry about damaging the teeth on the flywheel with the screwdriver technique. so i filled the #1 chamber with nylon rope at the bottom of the combustion stroke (so that the valves would be closed and avoid possible damage) and then continued cranking until the piston couldn't travel any further up due to the rope. then put a 24" breaker bar on the bolt, stood on it, and the bolt gave.

btw, first tank on the vx just came in at 18.6 km/L, or 44 mpg. pretty good, especially considering that the timing was off the whole time. i look forward to tweaking it more and improving that a bit.

[30mpg]

I got msd wires and new cap and rotor to help with mpgs it also makes the car run smoother