buick 225 oddfire - not firing on 2,4,6

I have the dist. wrench and it works pretty good but so does a socket with a swivel.

 

Re: buick 225 oddfire - not firing on 2,4,6 -fail

So I was pretty careful to rotate the distributor shaft 180* tonight. It wouldn't start.

2nd try I found TDC and did it again. As soon as I started the jeep it must have fired through the carb. There was a pretty loud bang and some smoke. Nothing looked burned but I gave up for tonight.

What am I doing wrong and what should I look at now that this happened?

 

If you're absolutely sure you've got it at TDC and indexed to #1, then next thing is timing. Do you have a light?

To get it to start, it just has to be "in the ballpark." Install hold down, but leave the bolt loose so that you can rotate the dist with some force, but not loose enough that it will rotate on its own with engine vibration. Start it and quickly rotate the cap until the idle smooths out. Then put the light to it. You really need a vac guage, too, but just get the 5* initial set for now.

 

by indexed to #1, you mean that the rotor contact tang is pointed at the #1 point on the distributor cap correct?

I had it set like that and that is when I got the loud bang and saw some smoke from the engine.

I have a buddy with a light, but I was just hoping to get it close that all 6 were firing, then tune it with the light.

thanks

 

While hoping this is not the case, and double and triple check to make sure the distributor timing is correct, it's possible the timing chain is worn out and has jumped time. A way to check how much play you have is to have the distributor cap off with the distributor installed. Put a breaker bar or similar on the crank bolt and gently and slowly move the crank back and forth while watching the distributor shaft. If in good shape the distributor shaft should move almost immediately with the movement of the crank. If the crank moves quite a bit before the distributor shaft does then you have too much play in the timing chain and sprockets and could have jumped cam timing. The distributor is driven off the cam so if the crank and cam isn't timed together correctly your ignition timing will be way off too.

 

i just installed a HEI in my 225... i had the same vary loud backfire (scared the @$#@ out of me)

you have it 180 off.. first line the timing mark up on the balancer to 0 TDC
assuming its on the compression stroke and looking at it from the driver side fender its probably pointing at about 4 or 5 o-clock.. you want it pointing at about the 10 o-clock position..
i finally got mine set right after alot of aggravation but its running good now..
here is a pic of where my distributor is now with plug wire 1 circled..



hope this helps....

 

I recently replaced my distributor, lost the timing in the process and was able to reset the timing using the following procedure. I have a Delco-Remy Distributor

1) Set the #1 cylinder to TDC - make sure it is in compression by noticing that the valves for this cylinder are both closed. (the lifters will have no tension on them)

2) Set the rotor so the leading edge is just beginning to make contact with any of the six contacts on the distributor cap. - this contact will be cylinder #1 ( I chose a distibutor contact that allowed the spark plug wires to reach and allowed the dwell window on the distibutor to be accessible.) You adjust the rotor cap by rotating the distibutor housing (loosen or take off the hold down bolt and collar first)

3) Run the rest of the spark plug wires in the firing order of the engine. 1-6-5-4-3-2

4) My engine started roughly at first. After I rotated the distibutor about 15 degrees counter clockwise it ran smoothly enough for me to set the dwell.

5) Dwell - about 29 degrees @ 550 - 650 RPM

6) Timing - 5 degrees before TDC

Dwell setting will affect the timing - so set the dwell first.

Good Luck!

 

One other remote possibility, could you get us some casting numbers off the block? Every once in a while an odd 225 gets confuzzled for an even 231 and vice versa.

 

Happened to me. I was running a 225 dist with points,condensor etc... from a 225 in my EF 231. Runs much better now with a HEI!

 

hey all,
well I tried again tonight and this time it fired right up! Whoot Whoot! I had the distributor holddown tight, but I was able to rotate the distributor to fine tune by ear (as mentioned a few post above). It was running pretty well. I am still missing on 6, 4 is a little weak but the others are strong. whew. back to where I started! Well, a little progress I guess. Plus I am learning quite a bit too.

so, I am going to set the dwell and time it when either a) I buy the light and meter or b) when one of my buddies can swing by with his stuff.

thanks a lot for all the help!

 

looked at this a little more yesterday.

I found TDC on #1 on the compression stroke.
Set the distributor so the leading edge of the rotor tang would contact point #1 on the dis. cap.
Set all other wires in firing order, 165432.
Fired it up.
I played with the timing by ear until it sounded pretty good. I disco'd the vacuum advance and pluged it on the carb side, so the vacuum pot on the distributor was open to air. Set the timing to 5* BTDC.

It still seems to miss on 2 and 6. I can pull the wires off the cap and there is no real change in idle.

Also, it now backfires badly from #4 when under load. There is a lot of grey smoke now too.

I did a compression test and all cyls were about 165-170 expect #4, which was 30. I may try again today. I did the check by pulling all the plugs and insertin the gauge into on cyl. I disconnected the coil wire at the distributor end and grounded it. Cranked it over wide open for 7-8 times. It would jump up to 90 on the first one and then stabilize at 165 or so. Didn't leak down until I vented the gauge.

2 things I haven't messed with are dwell (I don't have a way to set that) and setting the points. Not exactly sure how to do this.

So...am I off with the distributor again? 180* I am not sure what I did to cause backfiring/low comp on #4.

thanks in advance, jim

 

Jim,

I think you have two separate problems here. I don't see how low compression in the #4 cylinder can be a timing problem. It must be either valves or rings.

As far as the 6,4 &2 Cylinders not firing, I have read that it is possible for the odd fire engine to run on half the cylinders. This happens when your distributor is off by one contact. Why don't you try setting the engine back to Top Dead Center - then move all of your spark plug wires down one position in the direction that the rotor rotates. (put the #1 wire where the #6 was, the #6 where the #5 was and so on) Do everyting else just as you stated in your last post and see what happens.

Hope this helps.

Joel

 

Hi all,
I had some more time last night to work on this. The jeep is running and firing on all 6 cyls now. It still seems like when I pull the plug wires off 1,3,5, idle drops much more noticeably than 2,4,6. However, there is a change so that is a plus. Does anyone else notice this?

I have no idea what I did differently this time around, but there are a few steps in there so I am sure I could have gone wrong somewhere. If I had to guess, it was always one tooth off on the distributor and I couldn't rotate the cap enough to make it fire correctly. However, I learned quite a bit about this engine during this process so that is great.

Once the rain stops (I love Seattle by the way) I will take it for a good run, and then pull the plugs to check compression and plug condition and possibly recheck timing.

whew. thanks again all.