440-3 spark plugs

[jipjob]

Sent: 2/23/2004 9:20 PM

Well this is interesting, I went down today and got the new plugs and they are Champion. Installed with hesitation after looking at the old plugs (which have no gasket on them) I replaced them with ones that do have sealing gaskets. Now one side went in really smooth and I started up and it ran great!. So I went to the other side and do you think I could get those new plugs (Champion) to start back in the hole where I took out the old ones. No way I spent about hour reaching between the manifold and the sheetmetal that protects the inside of the engine and I could not get one of thoes little bastered to start. Now you tell me why one side would be like smooth as toast and the other the plugs from hell!

What kind of plugs should I have in this rig? Peanut type or the ones that have a gasket. Boy I don't know who I pissed oft but I really a little bit mad at such a small procedure. Like I said befor once I got the new plugs in (4) I started it up and it really smoothed out but what to do with the other side? Jon

[mightybooboo]

Sent: 2/23/2004 9:35 PM

Restarting those plugs is easy.Take a piece of fuel line about 12 inches long that will fit over the plug insulator,them just push the the plug up to the hole with it and start twisting,they will thread in pretty easily.
BooBoo

[jipjob]

Sent: 2/23/2004 9:48 PM

Ok I will try that but what I really want to know is?  Which type of plug does these old winnies call for the one that has a gasket to seal it or the one that has a tapper on the top of the tread on plug. Or does it make difference?

[Lefty]

Sent: 2/23/2004 11:06 PM

Take a short piece of 3/8" fuel hose and use it to extend your reach to start the plugs. Are you sure that you have the same part # as the other side? perhaps they gave you 4 of one part# and accidentally gave you another box of 4 of a different part #. I work in parts, so I know that it can happen.  Lefty

[jipjob]

Sent: 2/24/2004 12:24 AM

No the plugs came out of the same box. I was a little concerned when I noticed that the sealing area was different and when back to the Auto store and they assured me that the new plugs would work just fine. Well it was really nice to lite oft the old engine with just the new four plugs and see the difference and also hear. I just can't wait to get the new plugs installed on the other side. Will let everyone here know how it comes out and how much skin I have left after fighting that left bank on the old 440.

[mightybooboo]

Sent: 2/24/2004 10:48 PM

My book shows BL-9Y plug for the 74-75  440 R-M chassis, doesnt show a pic so dont know if it has the gasket or not.  Sounds like a Lefty question to get the right answer.
BooBoo

[enigma960080]

Sent: 2/24/2004 10:55 PM

If its a 440-3, it  will (Should) have the  5/8 inch  gasketless taper plugs.

[Radioal1]

Sent: 5/24/2004 7:52 AM

I went through the spark plug issue with my '78 440-3.  The problem is that most auto parts stores do not show the -3 as taking different plugs that a "regular" 440.  They DO as the -3 has completely different heavy duty heads.  You do need the tapered seat plugs just like in the picture.  I got mine by using the old plug number rather than the parts store computer recommendation.  I don't have the numbers in front of me right now, but the numbers posted by Enigma sound real familiar.

Luckily, the threads are the same so no permanent damage was done by using the wrong plugs, but the engine ran very badly because the gap was recessed nearly 1/2" into the threads of the head.
 
Al

[TheWoodShaver]

Sent: 5/24/2004 9:31 PM

This discussion has been so good it would be a shame to stop it, but the following is from the 1978-1979 chassis manual for the M300 - M600 series chassis.

360-3 Engine - MOPAR 2444485 or Champion RF-10 18mm tapered seat, gap = .035", No gasket

440-3 Engine - MOPAR 4091938 or Champion OBL9Y 14mm tapered seat, gap = .035", no gasket

If you go to the Champion home page and search for either of the plugs shown above, you will get a reply indicating that they do not have either of the plugs requested. They do however show RF-10C as the equivalent of the RF-10 and as shown in a previous post by enigma the RV9YC is the equivalent of the original OLB9Y.

Hope this will help resolve the question,
Woodshaver

[Oz]

Sent: 6/9/2004 2:24 PM

I just replaced the plugs on my 440-3 with NGK Iridium IX plugs.  These are the best NGK has to offer.  They cost about $64 a set.  The part number is #7401 (UR4IX). - Sob

EDIT at at later date:  DO NOT spend the money for these.  After running them for a couple years, I found no difference from using the much less expesive, OEM plugs!

[Jlogue88]

Sent: 7/9/2004 5:23 PM

There is a removable panel on the sheet metal on that side for getting at the plugs.

[tcactyl]

Sent: 7/15/2006

I have recently replaced the plugs on my 440-3 with champion RV12-YC which one 'specialist american part supplier' here in the UK has listed as being the correct plug  ...however I believe it should be a cooler plug i.e. RV-9YC as I noted in various threads....will this do my motor any damage ?
Thierry

[denisondc]

Sent: 7/15/2006 8:02 AM

      I would think it would be okay with either of the plugs you mention.    The hotter heat range plugs would only cause damage if detonation or 'ping' resulted.  You should be able to hear the 'pining' when driving, mostly on long upgrades at moderate speeds, where you have the gas pedal down to keep up speed - but not enough to cause a down shift.  It would be a barely noticeable high pitched irregular-but-rapid clinking sound.   If its not pinging, there wont be any harm.   These are not high-compression engines, maybe about 9 to 1.

    I like the color of my plugs to be a light beige. If they are light brown thats okay too.  If they are white, I would retard the spark a couple of degrees, and check the plug color in another 100-200 miles of use.   My 413 has a compression ration of 8.5 to 1 I think, and uses the -12-YC plugs.

    The cooler plugs would not hurt anything either.  If you have plug fouling with the cooler plugs, then your ignition is either not firing early enough, or you have bad piston rings, or the carb. is way too rich, etc.

[Cooneytoones]

Sent: 7/16/2006 11:10 PM

I have a 440 just changed the plugs, Autozone and NAPA list them as R12 YC...their listing is for an MB 300 with a 440-3 engine....they were also what came out of it....

Timmy

[jbmhotmail]

Sent: 7/17/2006 2:57 AM

Were all 8 plugs that you removed the same spark plug number? Try matching threads of the old ones to the new ones.
Good luck

[DaveVA78Chieftain]

Sent: 10/27/2006 2:01 PM

Additional info 440-3 plug info:
14MM; .460 reach; 5/8 hex; tapered seat; resistor type; gap = .035"
original plug: Champion BL8Y (no longer available) which is replaced by Champion RV9YC
equivalent plugs:
Autolite: 23 (Traditional), AR23 (racing), AR12 (racing), AR13 (racing)
NGK: 2623 (Traditional), 5034 (Racing), 4449 (racing)

Champion RV12YC will fit but I suspect it is a hotter heat range.
Platinum plugs do not appear to be recommended
Most likely best to stay with the traditional versions for MH applications.

Dave

[vacuumbed]

I have a 1978 Pace Arrow with the 440-3. It uses the peanut plugs.

I have upgraded the ignition system with a ignition coil from a Ford Taurus, and an upgraded distributor with a post type cap. I also installed 8mm wires. This puts it in line with the HEI distributor used in GM vehicles of that era.

I then installed AC Delco R45TS spark plugs gapped at .045. This is the same gap that GM uses on this plug on HEI equipped vehicles.

This was 3 years ago. The 440 runs amazingly well. It passed emissions the first two years just fine. Last year it had trouble passing. I'm going to replace the plugs in it again before I take it to get smogged this year. I'm either going to go with the AC Delco R45TS or the Motorcraft equivalant.

[DRMousseau]

Been looking for additional info on spark plugs for the 440-3.

Back in the heydays of Detroit, engines and/or engine heads, were designed around the spark plugs that were readily available for the purpose intended. This was a major reason that the heads of 440-1 and the 440-3 were so significantly different. The recommended RV12YC for the 440-3 is significantly different from those recommended for the 440-1. The projected tip, thread reach, heat range, were all considered in the application purpose of the 440-3, which also facilitated the need for those extra "cooling passages".

BUT,... Detroit no longer manufactures THOSE spark plugs!!! My recent purchase of set was VERY disappointing in the quality that Detroit products had at one time created and maintained. Misaligned ground strap, offcentered ceramics and electrodes, and electrode tips that appeared to be hand-cut with dull diagonal wirecutters!!! Yes,... they were manufactured beyond our nations borders without care or concern!! These were READILY VISIBLE FLAWS and were jus poorly made!This has caused me to consider an alternative spark plug of better quality. Spark plugs are far more important than most folks realize.

So HERE, I notice someone using something different. AND,... after some research and greater consideration, I will be changing out my "new" spark plugs soon. It seems that the American made NGK V Power Spark Plug UR5 â€" 2771 NGK Spark Plugs, are a perfect match for substitution in the 440-3,... and may be MUCH better!!!

The recommended spark plug gap has been pretty standard at .035" for the 440-3, big enough for a decent spark without overwhelming the coil output, small enough to provide easy cold weather starts and overcome any deposit build up that might otherwise cause misfires. I have recently noticed a slight "ping" and occasional "run on" when shutting down the engine. Sure enough, the tight gap was firing thru with probably a weak spark, hiding any misfires, but the build up of deposits were causing "hot spots". Being "old school", I tend to pay close attention to my spark plugs, and gap them a bit more to the plug manufacturers recommendations rather than the vehicle manufacturers suggestions. Missing is more noticeable when slight buildups occur, but that means it's time for a tune up!!! I've been getting a steady 7-7.3mpg for the last 3000mi,... lets see what the next thousand brings me. It certainly starts and runs better!!! And that's not to say that it wasn't before,... always been easy starting, and aside from a lil ping lately,... it has always run GREAT!!!

AND,... that's with junk spark plugs!!! UGH!!!!

[DRMousseau]

Soooo,.... HERE  are the results of the next thousand miles!! Nothing more than spark plug change, new air filter, with oil and filter change.

First run, 18 gal at 8.3mpg!!!! I was delighted!!!
Second fill, 21.5gal at 8.5mpg!!! VERY delighted!!!
Third fill, 25gal at 8.9!!!! VERY  UNEXPECTED!!!
Fourth fill, 20gal at 9.9mpg!!! UNEXPLAINABLE!!! I was SHOCKED!!!!
Fifth fill, 27gal at 10.0mpg!!! Speechless!!!!
Sixth fill, 22gal at 8.9mpg. A hard run at above average speeds.

I arrived at my destination on my seventh fill and have not yet filled up. While I understand the "improving" mileage from "plug break in", I'm very curious to the last, slightly diminished, mileage result. I'm gonna remove the plugs for inspection and replace with new NKG plugs for the next venture in about a week. I expect to see one or two a bit more fouled than all the others, given the results I see.

These results were nothing short of being VERY surprising for me. While I've always seen improvements after a spark plug change, it usually included a full tuneup of other ign parts, or at the very least, cleaning and adjusting points and timing. This time was ONLY a plug change. Air filter wasn't bad enough to be changed, but I did out of habit. I've never seen much improvements in mileage from air filter or oil changes, so I can only really attribute this to a plug change and careful gap adjustments. EVERYTHING is mostly unchanged from the previous 2thousand miles!!! Same load, tires, roads, and other circumstances. And the last 1000mi trip, and the 2000mi of short runs since then, has seen a solid 7-7.3mpg. THIS IS A 10-30% gas milage improvement!!! NEVER have I see such dramatic results from spark plugs!!!!

The 440-3 in industrial applications of light trucks and RVs is pretty solid, reliable and consistent. To personally see and experience this kind of improvement from a simple spark plug change, will now keep me on my toes jus a bit more now.

[Rickf1985]

From your worst to best is only a 1.7 MPG change. That is negligible and could very well be attributed to road condition. At the low end were you in hilly terrain and on the flat in the high end? Which way was the wind blowing, toward or from behind? How was the traffic? start and go or clear? How many stops did you make, same on each run? A stop and start will decrease the mileage. For the small changes you have I doubt the plugs have anything to do with it and if you have any fouling at all then you have other issues to deal with. One or two plugs fouling is a sign of engine troubles. All plugs fouled is a sign of too cold of a plug.

P.S. You are comparing short runs to long runs so the 30% is a false figure. You are comparing two totally different driving styles and they cannot be compared as far as mileage goes. You have to compare apples to apples.

[DRMousseau]

Before plug change,.... 7-7.3mpg for 3000+mi

AFTER plug change,... 8.3-10mpg for 1000+mi

Over the course of a thousand miles, generally up hill from 60' above sea level to over a thousand foot elevation at journey's end. The trip TO Florida is the first thousand of that 3000 at 7.3mpg. This return trip is GREATLY improved!!!

I DO have A LOT of added weight on this return trip, that was NOT a part of the first thousand mile trip and has been accumulating over that first 3000mi.

An improvement from 7.3 to 8.3 is good!!! From 7.3 up to 10mpg is DAMN good!!!

I expect one or two SLIGHTLY fouled plugs due to valve guides,.... Nothing unusual for an old engine and expected. The plug change showed nothing more than someone was lazy and didn't change the drivers side bank of plugs last time.

[Oz]

Naturally, if the data wasn't tracked using multiple runs under the same conditions, there will be a variance due to multiple aspects of the different conditions.  Nevertheless, it's reasonable to assume that the spark plug change did contribute a percentage of the improvement, although there's no way to determine exactly how much since the driving conditions varied.  Even if it were only .5 mpg due to the plugs, that's a substantial fuel savings over such distances.

It's an amazing and very good thing you had improvement on the return trip.  Going to FL is mostly downhill, and mostly uphill on the way back!  Would be interesting to see what mileage you'd have going to FL now.

Yes, there's other mechanical factors involved with engine fuel efficiency alone as well, but I think the bottom line is that it's important to have the correct plugs, in good condition and with the proper gap to start with.

[DRMousseau]

Well,.... I could replace all with the plugs I took out,... they are numbered, and carefully packaged. But the as the drivers side plugs were pretty poor, and I was surprised that the one in #7 was even firing, I'd rather not. Such a difference from one side to the other, that I'm assuming someone was too lazy to wrestle them out. Or at least I'm hoping so. Otherwise I jus might have a poor left side, bad guides, valves, head gasket, whatever.

After a thousand mile run, I'm a bit anxious to check the plugs which will show signs of any problems. I've also been wanting to check plug wires some damp, foggy, dark night.

I really have no great doubt that the plug change made a great improvement, jus surprised at an improvement of up to a 3mpg difference! Last month I saw a problem when I didn't replace a plug wire securely. Most wouldn't notice a single missing cylinder on a big eight. I have a hard time with an occasional miss from a fouling plug, but a dropped cylinder really stands out to me! Especially in a heavy vehicle that depends on every hp available. Jus one dropped cylinder can make a dramatic difference in mpg!!!

I also expected a good improvement since I gapped this set at .045", which has the same effect as advancing the timing significantly. I don't have the ping I noticed with old set of plugs, if I had, I would have set the timing back a bit. This is what I usually have to do since I typically time engines "hotter" than most mechanics who "stick to the book". I still may have to retard a bit, since I experienced a unique symptom on the journey here, that is typically a result of "hotter spark".

Dang! I sure luv workin' on classics!!!

[TerryH]

When dealing with plugs and pulling and checking all 8, you may get an awful lot of information re your engine. Especially when comparing each plug. Can show you individual cylinder problems for valves, guides, leads, plugs, head gaskets, ports, firing, etc., etc., etc.,.
Well worth inspecting and evaluating each plug. Each plug you evaluate corresponds to an individual cylinder. Often problems with one or two adjacent indicate something you may not have anticipated, and not necessarily related to a single cylinder.
Lots of info out there for diagnostics.

[DRMousseau]

Well I pulled those plugs today,.... only 1200 mi on 'em, but I wanted to know a few things, and tomorrow I'm headed out with the family on an 800+mi excursion thru Michigan's upper peninsula.

A bit better than I expected,... of course I tend to prepare for the worst! LoL! Number 2-8 were GREAT, with #8 showing jus a barely perceptible difference. All were VERY light tan in color tending toward light ash. The .045 gap MAY have been excessive. I experienced some high engine temps that may have been the result of the "hot" plug gap, or maybe it's a potential cooling problem. Temps were pretty high on the trip here, but I've not any prior experience or knowledge with the rig, having only had for about 7mos.

Numbers 1-7 were quite the same with #7 showing jus a light bit of fouling around the body base. This was the same plug that was the worst of the original set I replaced a was barely firing then.

So now I know my engines weak spots, replaced the set with NKG-UR5's at .040 gap this time. I'll be running in MUCH cooler weather conditions and a bit easier daily runs. AND,.... I'll pull 'em in about 1000mi or so, in about two weeks when we return! I'm also hoping the NKG's are indexed a bit better then what I jus pulled today, and also expect them to run jus a touch cooler. We'll see then!!!