Perhaps this will help? the firing order is cast into the valve covers on
mine...used to know it off the top of my head...
http://www.jeepsunlimited.com/forums/showthread.php?t=142386
On Sun, Jun 9, 2013 at 6:31 PM, Ethan Brodsky <brodskye@...> wrote:
> This question is directed to anybody who has an odd-fire 225 in^3 V-6. I'm
> trying to trouble-shoot some ignition problems and it'd be nice to talk to
> somebody who a similar engine. I noticed that Dave Rusilas discussed
> having this engine in a post ~5 years ago (and again in 2010), so I'm
> hoping he's still got his and is reading the list.
>
> My points started sticking over the winter, so I opened up the distributor
> (first time since I bought the boat in '04) to clean them. After that the
> engine would start and idle just fine, but is popping (misfiring) under
> load. I think that may just be due to the points still being dirty and
> I've got some new ones coming (thought about doing Pertronix, but decided
> to replace the points instead) but that's not my main concern.
>
> The distributor is just as described by Dave below - a Delco Remy unit
> with mechanical advance, a screen on the distributor cap (which has evenly
> spaced contacts, both inside and out), and an elongated rotor.
>
> While I had it apart, I noticed that the order of the plug wires makes no
> sense. My OMC dealer service manual (for the exact make, model, and year
> of my boat) says that the contact on the distributor just to the "right" of
> the screen is #1, and that they increase in a clockwise order (looking from
> the top). But when I look at my distributor cap, the one marked #1 is
> exactly aligned with the screen and they increase counter-clockwise.
>
> My understanding is that the portside cylinders are 135 (front to rear)
> and the starboard cylinder are 246. The firing order marked on the valve
> cover is 165432, so I would assume that cylinder 1 should go to contact 1
> on the distributor cap, cylinder 6 to 2, cylinder 5 to 3, cylinder 4 to 4,
> cyl 3 to 5, and cyl 2 to 6.
>
> This isn't how it was wired though, either in the anti-clockwise order
> marked on the cap or the clockwise order specified in the manual.
>
> Unless my notes were wrong, they were wired as follows:
> cylinder numbered contact on distributor
> 1 2
> 2 1
> 3 3
> 4 4
> 5 5
> 6 6
>
> I can't come up with any rotation or reversal of this pattern that would
> yield the pattern I'm supposed to get. I'm wonder if I wrote down the
> ordering incorrectly? It seems unlikely, as I marked the wires one at a
> time in order as I removed them and it idles fine with the current
> configuration, but who knows? If my notes are correct, it's probably been
> that way for years.
>
> I am pretty sure that my engine is the odd-fire - the casting number on
> the block is 991503, which is supposed to be "V6, Odd-Fire, Kaiser Jeep
> Corp/AMC". I didn't look at the cam in the distributor, but the rotor has
> the elongated arm described by Jeff.
>
> To determine if your engine is an odd-fire, look at the casting number
> (visible on the top of the engine, at the back where it bolts onto the
> intermediate housing) and match it up with this list:
> http://nmr.mgh.harvard.edu/~**reese/**BuickV6CastingNumbersandIntern**
> alSpecs.pdf<http://nmr.mgh.harvard.edu/~reese/BuickV6CastingNumbersandInternalSpecs.pdf>
>
> If anybody has an odd-fire V-6, is there any chance you could look at the
> distributor and tell me:
> a. Which port is #1? (relative to the screen and the front of the engine)
> b. Do the ports increase clockwise or counter-clockwise?
> c. What is the part number on your distributor cap?
> d. What order are the cylinders wired to the distributor?
>
> Thanks!
>
> Ethan
>
>
> On Wed, 30 Jul 2008, drusilas@... wrote:
>
> Jeff,
>>
>> My boat is a 1969 Sportsman with an odd fire 155. It doesn't have the
>> original block but I'm pretty sure that
>> the distributor is original. It's a Delco Remy w/ centrifugal advance
>> only. I'll try to get a distributor
>> number off it later. The cap is held down by 2 screw latches and there is
>> no gasket. It has a spark arresting
>> screen breather on the side where the point's adjustment port would be on
>> the auto version of the cap. The
>> contacts are spaced evenly, 60 degrees apart from each other. The
>> difference is in the rotor. Its contact is
>> elongated by 15 degrees of arc to allow it to fire at both 45 and 75
>> degree intervals. The cam on the
>> distributor shaft may have 45 - 75 spaced lobes. I'll look at it when it
>> gets light outside and get back to
>> you.
>>
>> I think that the irregular spaced cap contacts that Lee is talking about
>> are on the Delco HEI distributors. I
>> tried to install one once but it wouldn't fit because the diameter of the
>> cap is so large that it interfered
>> with the thermostat housing. I opted for a Pertronix Igniter system
>> instead and it works great. It uses a Hall
>> Effect trigger set off by magnets on a ring which mounts below the rotor.
>> Magnets are spaced around the ring at
>> alternating 45 and 75 degree intervals. The part number is 1165 if you're
>> interested.
>>
>> Dave Rusilas
>>
>>
>>
>>
>> -----Original Message-----
>> From: JEFF DOOD <jdood@...>
>> To: Evinrude & Johnson Boats of the 1960's and 70's <
>> omc-boats@...>
>> Sent: Tue, 29 Jul 2008 10:54 pm
>> Subject: Re: [OMC-Boats] timing/carb adjustment
>>
>> awesome! i think i need to check out the underside of all my collection
>> of caps and see what's up. then make sure i try this whole thing over
>> with the odd fire distributer in there instead and see what happens. esp
>> if it would start, but not have power past 10 mph otherwise. sounds just
>> like what my prob might be. plus i am armed with more info to quiz my
>> mechanic about.
>>
>> on the car vs marine distributor topic though - i need some solid info.
>> i have heard car distributors are illegal and get you big fines if
>> discovered by the coast guard. also heard the reason is due to the seal
>> around the cap. marines are screwed down, cars are not. spark can
>> get out without screwed down seal. escaping spark can blow things up.
>> fine or no fine, not interested in the blowing up part. so are the
>> delco's just behind the times and everything since has been brought up to
>> more stringent safety standards? and if the delco ends up working best
>> with my engine, should i be concerned about it not being a marine
>> distributor?
>>
>>
>>
>> On Jul 29, 2008, at 4:34 PM, Lee Shuster wrote:
>>
>> > Jeff,
>> >
>> > Sorry if I confused you with a little too much info. I'll make it a
>> > little easier to understand:
>> >
>> > Since the distributor is gear driven off the camshaft, and the >
>> camshaft
>> > is driven by a 2:1 gear off the crankshaft, I could have explained the
>> > odd-fire timing interval in DISTRIBUTOR CAP DEGREES not relative
>> > CRANKSHAFT DEGREES. It's very helpful if you view
>> > http://home.off-road.com/~**merls_garage/oddfire.html<http://home.off-road.com/~merls_garage/oddfire.html>
>> >
>> > Let's look at your Mallory cap and assume for a minute that it is > for
>> a
>> > EVEN FIRE ENGINE: You are correct 360 / 6 (evenly spaced distributor
>> > posts is 60 degrees apart on the INSIDE of the distributor cap. I was
>> > correct in saving 120-120-120-120-120-120 of crankshaft rotation for
>> > each firing point because the crankshaft turns two revs for each rev >
>> of
>> > the distributor.
>> >
>> > If you examine in the INSIDE of a DELCO REMY ODD-FIRE Distributor you
>> > will notice UNEVEN spacing of the contact traces. BUICK engineers
>> > altered the contact area to match a 45-75-45-75-45-75 degree pattern.
>> > The external wire sockets are NOT altered, the still are in the >
>> classic
>> > 60-degree spread. Pretty trick, eh?
>> >
>> > So as they say, your mileage my vary, but I suspect a +/- 15 degree
>> > isn't enough to keep the engine from starting with the wrong >
>> distributor
>> > cap. But I can well imagine, it doesn't idle very well and doesn't >
>> want
>> > to run more than 10 mph.
>> > So is it a case of mis-matched distributors?
>> >
>> > How do you solve this mystery? One certain way is to pull off a >
>> cylinder
>> > head and observe the piston timing. Another way might be to start
>> > looking for GM casting numbers or OMC serial number plate on the block
>> > and try and determine if you have an odd-fire 225 or an odd-fire > 231,
>> or
>> > an even fire 231 or even fire 252. I guess another method is trial and
>> > error substitution. And don't forget -- firing order matters, as well,
>> > as you have noted.
>> >
>> > It's too bad the mechanic didn't take notes or write what he did. It
>> > would be nice to get back to a known starting point, in figuring out
>> > where you are and where you are going. If your Buick came out of a
>> > dual-engine boat it is probably an odd-fire 225, but you can't be
>> > positive someone didn't change them out.
>> >
>> > It still sounds to me like you did get into an even-fire distributor
>> > with the Mallory. Don't worry about the vacuum advance that's the >
>> least
>> > of your problems. And I don't believe that OMC used marine-grade DELCO
>> > REMY distributors, but I could be wrong on that on the V6 Buicks.
>>
>
> --
> <a href="http://homepages.cae.**wisc.edu/~brodskye/<http://homepages.cae.wisc.edu/~brodskye/>">
> Ethan Brodsky </a>
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>
Received on Monday, 10 June 2013
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