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EA82T cam and ignition timing expert required

Posted: Thu Aug 24, 2006 7:32 pm
by r00fi
This is a bit long, so please put on your comfy slippers.

1. RX was going OK but used to mis-fire occasionally and didn't have a lot of power, so I thought I'd put an as-new distributor cap and rotor from an old EA82T

2. Installed parts, started and car ran - although a bit rough.

3. Drove out drive and obviously something was wrong

4. Went back to garage and re-checked plug leads - I had 2 wrong.

5. Fixed plug leads, started car and it idled smoothly.

6. Went to drive to work, car had NO horsepower but still idled ok. Was also getting very hot.

7. Tried putting old cap and rotor back in. Same problem.

8. Parked car and took train.

9. Scratched head repeatedly wondering why replacing distributor cap and rotor had completely stuffed my car.

10. Removed air-con and alternator to check cam timing. It 'seems' ok, but I don't have cam covers, so I'm not sure if the alignment is 100%

11. Checked ignition timing and it was waaay out.

12. Adjusted ignition timing to factory spec and car now goes much better, but sounds COMPLETELY different (kinda growls) and 'seems' to go much harder than it used too. But somehow it just doesn't sound 'right'.

13. Car now also seems to compression lock up a bit on starting.

14. The RX now idles at 2000 rpm cold and 1400 rpm warm, where it used to idle around 750-800 rpm warm.

My questions are thus:

a. Did I skip a tooth on my distributor side timing belt when the car was running rough?


b. Will an EA82T run if the cam timing is wrong?

c. How can I be sure of cam timing without cam cover alignment marks?

d. The car is a stock 86 RX, do I need to join any ECU plugs when adjusting ignition timing? (I did disconnect the vacuum hose)

e. Given point 12, should I just be happy that it's going?

Posted: Thu Aug 24, 2006 7:45 pm
by BaronVonChickenPants
Yeah sounds like it skipped a tooth and was running severely retarded, this can cause everything you've described, overheating, no power, was it going through juice like theres no tomorrow too?

Jordan.

Posted: Thu Aug 24, 2006 8:40 pm
by Suby Wan Kenobi
You sure you havent lined one cam 180 out?

Posted: Fri Aug 25, 2006 10:37 am
by r00fi
If I was 180 deg out, then would both the cam wheel alignment holes would be pointing up when the flywheel was on the alignment marks?

At the moment I have one up and one down, as per the FSM

Posted: Fri Aug 25, 2006 10:46 am
by Suby Wan Kenobi
No thats correct.

How do you know that the timing is spot on if you dont have any cam covers on?

With the timing on th cam a tooth out it will make it idle faster and my guess would be its retarded it

Posted: Fri Aug 25, 2006 4:58 pm
by r00fi
Suby Wan Kenobi wrote:No thats correct.

How do you know that the timing is spot on if you dont have any cam covers on?

I should have said "ignition timing is spot on".....

Posted: Fri Aug 25, 2006 8:47 pm
by Suby Wan Kenobi
The comp like lock up usually means your ignition timing os out to buggery but ifs that ok has to be a tooth out on the cam

Posted: Mon Aug 28, 2006 6:52 pm
by r00fi
So, an EA82T will run with wrong cam timing?

Is there anything else I can use to check the cam alignment without the cam belt covers? Maybe something on the head or by another method?

Posted: Sat Sep 09, 2006 1:25 pm
by r00fi
Also posted cam timing alignment on USMB

Answer here

http://www.ultimatesubaru.net/forum/sho ... hp?t=64107

Posted: Sat Sep 09, 2006 9:24 pm
by rx2rx2
I have easily replaced the timing belts three times now, last time @ 300,000+ km, (the only hard part is the hours to remove the A/C, alt, both fan assemblies, fan belts, rad shroud, water pump, crank pulley, etc, to get to the covers), & I always ignore the workshop manual's advice to rotate 180 deg between aligning each side as the right hand side I set to the alignment mark which is up, & the left can easily be seen if it is even 1 tooth out of alignment by visually aligning it down with engine marks & bolts, or I make my own alignment marks to match the belts pulley's before removing the belts, (line up the flywheel at TDC first).
If the belts have not broken, it is just a matter of loosening off the tensioners & sliding off the old belts then slipping on the new belts, tension & tighten, & check that the alignments are still the same.
Finally, I hand crank the engine over, (refit crank bolt & use a socket & ratchet to do this), then start & run it for several seconds to ensure that all is correct, (runs real quiet without the water pump, alt, fan, etc)before replacing all the covers & parts, (after stopping the engine first).