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type in cross autolite 295 and you get this:

http://www.sparkplug-crossreference.com/convert/AUTOLITE/295

* NGK: B4

* Accel: 124

* AC Delco: 45

* AC Delco: B403I

* AC Delco: B45

* AC Delco: S46

* Autolite: 295

* Bosch: WR9EC

* Bosch: W9EC0

* Champion: J11C

* Champion: J8C

* Denso: W14-U

* Lodge: BAN

* Mopar: 4339491

* Motorcraft: AS8

* Motorcraft: A7

* Motorcraft: A7C

* Motorcraft: A7X

* Prestolite: 14-07-01

* Splitfire: SM029E

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Heat range is defined as the distance from the electrode to the nearest water jacket in the head. A tired old engine may require a different heat range than a freshly rebuilt engine. As not all engines are the same the spark plug color is the best indicator of the correct heat range for any specific engine.

Scan119June0820082.jpg

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Perhaps I should have worded my question differently.

I should have asked if the plugs I had were in the ballpark of heat ranges for one of these engines.

Hank; I am trying to get it started. It seems very close to catching.....but I think it is not getting enough fuel. Will take the carb down...again to see if something is amiss. Since it is a fluid drive I have the dashpot and it's linkage which may not be working correctly.....I ended up buying two kits from different sources and still had to get the dashpot kit from Roberts so the carb was apart for quite awhile and I may have something there that is still not correct. I will get it figured out.

On the plus side I got the wood out of the bed today and cleaned up all the sheet metal. Last truly dirty job on the old beast is done! :D Yeah!

I now understand why one of these trucks I looked at had a metal deck installed over the top of the old wood bed. :rolleyes:

Jeff

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Hank;

I don't know that I would describe it as a tough time. As we all know getting one of these back into decent shape after it has sat for decades is a fair amount of work. It is made more problematic by my lack of experience with Mopar products. By the time you throw in delays and false starts sometimes those little "details" get lost. I do know that I should have taken more photos of the carb and linkage before I took it apart.... oh well...what is done is done. It ended up being apart far longer than I expected.

Jeff

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No need for a PM. I'm following along, just haven't had a chance to chime in yet. It would appear from Hank's research on the Autolite site that either 295's or 306's would be fine. I've run 306's in my truck without any problems.

Does anyone know what the difference is between the two? I suppose a little more research at Autolite is in order.

Merle

Edited by Merle Coggins
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Ahh Haa... Research pays off...

The 295 is a non-resistor plug and the 306 is a resistor plug. Otherwise they are the same. Both have aproximately the same heat range according to the attached chart. (see line 7)

If you're not trying to listen to a radio with the engine running the 295's will be just fine.

Merle

ASP2009AutoliteHeatRange.pdf

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Merle;

Thank you.

I am not certain if it has anything to do with my starting issue but I do have a question about this fluid drive carb. There is some extra external linkage associated with the dashpot. Lever #14-41-22 has three holes in it for positioning the actuator linkage. Which hole are you using on your truck? Right now I have mine in the outboard (furthest from the cylinder head) hole. This arrangement is tied to accelerator pump linkage and seemed to give the correct activation. I am really uncertain if this might be causing the problem I am having getting this started. Any thoughts?

Thanks again for your assistance, Jeff

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The linkage on the left side is for the dash-pot. Only one screw connecting the two links. The linkage on the right, with 3 holes, is for the accelerator pump. I believe the different holes would change the stroke length of the pump. I kept it in the same hole as it was.

P9130788.jpg

As I understand it, the dash-pot is supposed to keep the throttle from returning to idle too quickly. I don't know the reasoning behind this as the added weight of the FD unit makes for more flywheel mass and thus slows RPM changes anyway.

Near as I can figure, the plunger lifts when you open the throttle and allows gas to flow under it. Then when you return to idle the gas is trapped under the plunger. I can't find any way for the gas to escape from under the plunger except for past the plunger lip. I looked and looked for some oriface that would allow gas to escape slowly but couldn't find one. Once I rebuilt my carb the plunger sealed so well that I couldn't get it to return to idle at all.

P9130784.jpg

P9130783.jpg

The screw in the top cover is right above the dash-pot plunger. You can adjust it to limit how far it will lift when the throttle opens. I guess this is to adjust how much "dash-pot action" there is upon return to idle. I've got mine screwed in so that the plunger stays all the way down and I don't have any stalling issues when returning to idle, so it's going to stay that way.

P9130777.jpg

Merle

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Thanks Merle;

Mine is set up in the hole on the opposite end of the link. As I was going through the carb instructions it said that pump travel should be 3/8". When i tried each hole in the link that was the hole that ended up with 3/8" travel on the pump. The others were more than that. So.......I guess I can try each hole and see what happens.

One thing that is bothering me about this carb ..... when I open the throttle I can't detect a spray of fuel into the throat. Is that normal? Most carbs I have worked on that seems to be the norm......this one no.

Jeff

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I'm running ac delco plugs currently *holding my head in shame*

only because napa had to specail order the autolite plugs :o

I believe I have AC plugs in my truck right now because that's what I could find quickly the last time I wanted to change them. I called the Napa store we use at work this afternoon and asked if they had 306's. He said he had 18. An hour or so later there was a set sitting on our Service Manager's desk for me. I plan to change them before my trip to Kalamazoo in a couple of weeks for the WPC meet. The AC plugs are working fine but the back two tend to get rusty from water getting into the spark plug pockets if I leave the truck uncovered during a rain. New plugs will make it look nicer for the show.

One thing that is bothering me about this carb ..... when I open the throttle I can't detect a spray of fuel into the throat. Is that normal? Most carbs I have worked on that seems to be the norm......this one no.

Jeff

I had that problem at first too. You either got the check balls in wrong or the passage between the pump and the nozzle is plugged like mine was. I cleaned and fished small wires through and got some gunk out. Then I found that I could remove the nozzle tube and got it good and clean. Now the pump works great.

Merle

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Thanks again Merle;

I will take a close look at this tomorrow.

For what it is worth....I have had decent luck with AC plugs over the years but by far I have gotten my best results using NGK plugs. They seem to have the right plug for every application and when you find it you are set.

Jeff

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Merle & Tim;

Yes. I discovered them about 30 years ago when trying to solve a fouling problem with a V6 outboard. Once I found the correct plug the improvement was nothing short of a miracle. Interestingly about the time I used them to solve my problem the engine manufacturer switched to them as well.

When I started digging into it and talking to mechanics it seemed that they were producing a full range of products that actually ran within the stated heat range when others were less accurate or did not offer a complete tuners selection. I do know that they offer several slightly different (hot to cold) heat range options for most applications. This can be quite useful in tuning away some problems.

As an example SBC's are prone to fouling the rear cylinders as they wear. I know for a fact that going up a heat range on those two plugs will buy you quite a bit of time.

I have a 1949 AJS 500 single that I have built to use as an desert play bike. It has a chain driven magneto, trials gearing and truly massive flywheels. Riding it is sort of like having a locomotive between your legs. With a NGK BR6HIX Iriduim plug in it, it will lug down close to 100 rpm and still produce crisp throttle response and usable power. I can even use the manual advance lever as a type of soft throttle at these low speeds. Getting one of these engines to produce power at around 200 rpm is not a problem but dropping below that is difficult. It took a while to find the right combination of settings, etc... but the end result is truly unique and very fun to ride.

Jeff

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Tim;

:D Yes....yes and yes. Associated Motor Cycles (AMC) owned AJS & Matchless and several others including Norton.

AJS were a dominant force in all forms of competition in the pre & post war years. The first post war 500 cc Road racing world champ AJS Porcupine. Arguably the most valuable motorcycle in the world today.

Where they really shined was the various forms of reliability trials. World champs over and over. Six day trials especially the Scottish were the ultimate test ground for manufacturers of the day. A performance by the great Gordon Jackson during the Scottish 6 days trial is their crowning achievement. One point off (one dab) in 6 days a feat that has never been equaled. Yes they were heavy by today's standard......but they were essentially the same machine you would buy to get to work on or fit a sidecar and haul the family around with.

Jeff

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