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Taking bets on what's wrong with my motor...

  • Thread starter Thread starter 68Coupe289
  • Start date Start date Apr 20, 2004
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68Coupe289

Founding Member
Sep 13, 2002
234
0
0
Lexington, KY
Apr 20, 2004
#1
  • Apr 20, 2004
  • #1
Ok. I bought this motor about 8 months ago for my car. Here's the run down (I know it repeats my other post):

040 over 289
.200 dome pistons
Edelbrock Performer heads (60 cc)
Comp Cams XE 230/236 .554/.558 110
Edelbrock Performer 600 carb
Edelbrock Performer intake (about to be replaced with Stealth)
Petronix ignition and coil

When the motor went in, it ran great. Then about 4 months ago I swapped some new valve covers, and accidently wired it backwards (I wired it with #1 being the driver front).

Don't laugh too hard. This is my first Ford.

Anyway, it still ran, so I didn't notice. It was just a little hard to start, and ran rich.

I probably put 1000 miles or so on it like this. When I realized my mistake and fixed the wiring order, it backfired horribly, and wouldn't run. So I pulled the distributor, TDC the motor, put in back in so I would know where #1 was, wired it up. Better, but it still ran rough. Keep in mind nothing else was changed (carb, etc).

Next, I timed it. Started a 6 degrees advance, and went all the way up to 14 degrees. No luck. Adjusted idle mix on carb. No Luck.

Swapped plugs and wires. No Better. Still ran rough.

Ran a compression test to see if I burnt a valve. All cylinders at 150 psi.

Took valvetrain apart. Checked lifters and pushrods. They are fine.

Pulled Cam. It's fine. No worn lobes. Got kind or frustrated at this point.

So now I'm putting it back together. I'm going to see how it runs. If it's still rough, I'm thinking about upgrading the ignition.?.?

So, my questions:

Did I miss something obvious?
Does it matter which point on the petronix that you pick for #1 (as long as it lines up at TDC)?
Do I need to up my fuel from 92 octane?
Any other cheap tests before I dump money on an MSD ignition setup?

I don't see how it could have ran good when I first had it, and now run like ass.

help
 

allcarfan

The Answer Man
Founding Member
Apr 8, 2001
2,458
1
56
North Atlanta
Apr 20, 2004
#2
  • Apr 20, 2004
  • #2
Im gonig to take a wild guess and say....

something


thats it 'something' is wrong with your engine
 
H

hindle

New Member
Jan 9, 2004
28
0
0
Flemington, NJ
Apr 20, 2004
#3
  • Apr 20, 2004
  • #3
Rough, as in it will barely run/idle? Or as in, it's driveable, but is really down on power?
 
6

68Coupe289

Founding Member
Sep 13, 2002
234
0
0
Lexington, KY
Apr 20, 2004
#4
  • Apr 20, 2004
  • #4
Rough, as in it will idle rough and remain that way when reved.

If I try to drive it, it misses and backfires badly.
 
J

jesserose17

New Member
Aug 21, 2003
219
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0
Southern CA
Apr 20, 2004
#5
  • Apr 20, 2004
  • #5
Ummm... I assume you made sure #1 is on compression stroke, not exhaust stroke when you marked it at TDC? Also, I assume you know that the distributor rotor rotates counterclockwise. If that doesn't solve the problem, I would check the timing chain, make sure it's not loose or jumped teeth.
 
6

68Coupe289

Founding Member
Sep 13, 2002
234
0
0
Lexington, KY
Apr 20, 2004
#6
  • Apr 20, 2004
  • #6
Yes, I'm sure that it was TCD on the compression stroke, and yes, I know it fires counter clockwise.

My timing chain is a new double roller. I checked it when I pulled the cam, and it was very tight, and the cam was lined up perfectly with the crank at TDC.
 
H

hindle

New Member
Jan 9, 2004
28
0
0
Flemington, NJ
Apr 20, 2004
#7
  • Apr 20, 2004
  • #7
Sounds like an ignition problem. Either the firing order is wrong, timing is severely off, something like that. Maybe you're dropping a cylinder and not realizing it.
 
J

jesserose17

New Member
Aug 21, 2003
219
0
0
Southern CA
Apr 20, 2004
#8
  • Apr 20, 2004
  • #8
My flamethrower II coil from Pertronix went bad after only 5 months... you might want to check that out.
 
6

68Coupe289

Founding Member
Sep 13, 2002
234
0
0
Lexington, KY
Apr 20, 2004
#9
  • Apr 20, 2004
  • #9
I swapped in another coil. Didn't help.

Keep the ideas coming though. I'm up for trying anything new at this point.
 
J

jesserose17

New Member
Aug 21, 2003
219
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0
Southern CA
Apr 20, 2004
#10
  • Apr 20, 2004
  • #10
Have you tried swapping the distributor? This is sure a mystery!
 
6

68Coupe289

Founding Member
Sep 13, 2002
234
0
0
Lexington, KY
Apr 20, 2004
#11
  • Apr 20, 2004
  • #11
That's the one thing I don't have another of. I'm prepared to buy a new distributer, but if I do, I want to do it right and get an MSD or Mallory.

But I'm trying to eliminate all the "free" possibilities before I start tossing money into it.
 
6

68Coupe289

Founding Member
Sep 13, 2002
234
0
0
Lexington, KY
Apr 20, 2004
#12
  • Apr 20, 2004
  • #12
Another thought I had: Could having it wired wrong for so long have damaged the pertronix in some way? Someone on another board mentioned that he thought what I did had "cross-fired the distributer to death". I've never heard of somethign like that happening.
 
J

jesserose17

New Member
Aug 21, 2003
219
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0
Southern CA
Apr 20, 2004
#13
  • Apr 20, 2004
  • #13
I don't think it would affect the distributor... they get worn out. The Pertronix being damaged is a possibly - for cheap fix, try the points and see if that solves the problem.
 

mrfomoco

New Member
Apr 18, 2004
108
0
0
The Woodlands, Texas
Apr 20, 2004
#14
  • Apr 20, 2004
  • #14
Damaging the Petronix is very easy to do. While working on my car I accidentally left the ignition to the "on" position for like 30 minutes and it roasted it.
 
J

jesserose17

New Member
Aug 21, 2003
219
0
0
Southern CA
Apr 20, 2004
#15
  • Apr 20, 2004
  • #15
Yes - Pertronix I has that problem if left in "on" postion without engine running. Pertronix II has build in shut-down if that happens.
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Apr 20, 2004
#16
  • Apr 20, 2004
  • #16
Check your Dist cap for carbon tracking between and across the terminals.
Next inspect the breaker plate if your using the stock Dist.
Look at the pivot points where the rivet goes thru, check for wear and sticking.
I had one go bad after I did a tune-up and about drove me NUTS.
trying to find out why it would not run or idle worth a dam.

PB
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Apr 20, 2004
#17
  • Apr 20, 2004
  • #17
Are the same cylinders missing? Let it run a minute or so, then dip your finger in some water and dribble on each header. If some are cold, try switching a plug wire from a good cyl. to a dead cyl. Will eliminate wires. If it is electrical it should be the same cyls dead. Also there are 2 firing orders for Fords. The only difference is the cam. Maybe try the alternate order.
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Apr 20, 2004
#18
  • Apr 20, 2004
  • #18
The cam #s you gave don't match anything in the comp catalog.
 
J

jesserose17

New Member
Aug 21, 2003
219
0
0
Southern CA
Apr 20, 2004
#19
  • Apr 20, 2004
  • #19
One possibly is that the cam's firing order is like 351 (also newer 302) - one easy way to check is to take valve cover off, starting with #1 intake valves, observe firing order while you turn it over 2 revolutions.
 

PoliceInterceptor

Keeper Of Automotive Oddities
Founding Member
Aug 5, 1999
2,161
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46
Live in GA, But could be any where really.
Apr 20, 2004
#20
  • Apr 20, 2004
  • #20
jesserose17 said:
One possibly is that the cam's firing order is like 351 (also newer 302) - one easy way to check is to take valve cover off, starting with #1 intake valves, observe firing order while you turn it over 2 revolutions.
Click to expand...

That is what I was thinking
 
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