FAQs about Ignitions

Timing a B-21

Date: Sat, 5 Oct 91 12:31:21 EDT
From: wiegman (Herman L. N. Wiegman)
To: u883399@sol.surv.utas.edu.au
Subject: timing B-21
Cc: wiegman@orion

G Day Tan,

>So, what is the best setting to attain a compromise between the two?

I go for 10 degrees BTDC (before top dead center) @ 1000 rpm. This is roughly what the manual suggest and will be a well balanced setting.

>My car accelerate well from standstill and doesn't ping, so how much is the lagging I should set, I meant how many degree?

sounds good to me. check your timing and see if it is about 10 degrees. If it is 4 or 6 degrees, rotate the distributor a bit (loosen the 13mm bolt behind it first with a ratchet w/ extension

>All wire connections and spark plugs are new.

ah, but what are gaps set to? spark plugs usually come out of the box with a gap of 40 mils (.040 inches). i would set them to .030 if you have the regular Bosch coil.

>Yes, the spark plugs are properly installed. You are right, the dealer might have done something nasty to my car so that I would go back to them again. Question is what sort of tricks they could have done on my car?

dealers generally don't try to trick your car into being sick again in X# of miles. But the assistant mechanic can easily forget to torque down on, or strip some threads on the spark plugs (from over tightening). I would simply check the spark plug gaps and then put a drop of oil on the threads before winding them all in by hand. The final step is to gently torque them into place. ... then "snap" the plug wires back on (make a good connection).

So far it doesn't sound like these are you problems, but these are all easy fixes.

>The fuel filter is ok, no grey or black smoke but I seems to stop hearing the fuel pump sound when I switch on the ignition key. She needs three to four attempts to get started in the morning. Atfer that only one attempt is required.

hmm. the fuel pump sound is ok. it is just getting the system up to pressure. if you go out to the car in the morning, turn the key and the pump buzzes once for two seconds, that is a ok. if the pump keeps buzzzing (this is with the key in position 2, with out the car running) then the system is loosing pressure somewhere or somehow. This constant buzzing is only acceptible when the weather is extremely hot, or if you are racing down the main strait of Watkins Glenn with a BMW on your tail and the motor is turning 6200 RPM.

>I use a 195/75 r14 tyres, does that made any significants differences

nope, the size sounds about right (stock should be (US spec) a 185/70 or a 185/80 ). I go from a 185/70HR-14 to a 205/60HR-15 set up. there the difference is 12%... the speedo never goes over 155km/h with my large tires on, but in reality i'm doing 174km/h

>This really frustrated me because my Nissan 120Y...

it is also much smaller and probably more aerodynamic than a swedishbrick. I have added an air dam, lower springs, and low restriction exhaust to aid in the speed department. The Nissan has no emmisions and a high winding motor.(does your volvo take unleaded fuel?)

>I notice some oil, looks like engine oil in the air filter box. See diagram below. Does this meant anything? ...followed by a fantastic ASCII drawing...

yeah, that seems to be the norm. My cars all have it to, but I can't figure out for teh life of me why it is there. The PCV does sent engine air back to the intake manifold, and there is always some "blow back" from the valves, but i get small puddles of the stuff, not just whisps of oil.

The only thing then is to check the exhaust restriction. Once you've started your car put your hand over the tail pipe, it should be a nice hard pulsation. If your keep your hand on the tailpipe you should be able to stall your car (or at least make it reduce it's rpm ... please don't show this to your kids)

Have you seen more than 150 in your 244 before? Your tire (tyre) size may have something to do with the "less than expected" speed. You can ask an enthusiastic friend to drive along side you and have them inspect your speed relative to their speedo. You can also run the car in 3th gear (manual) or 2rd gear (auto) [avoiding top gear] and see how many rpm your car will do. The manual usually shows you how fast each gear can do (maximum recommended speed per gear). this will tell you if your car is in the ball park. It will also tell you weather your car's engine can pull high rpm under medium load (top gear would be "full" load ). For these types of test you either need a tachometer or a friend to drive his car next to you to test speedometer accuracy. I would not recommend going over 115km/h in 3rd gear (manual) or 104 km/h in 2nd gear (auto). These roughly corespond to 6000 rpm (it depends on what rear end ratio you have as well).

keep 'em rolling,

Jacobs Ignition System Described

Date: Wed, 9 Oct 1991 18:22 EDT
From: RGOLEN@umassd.edu
Subject: Jacobs Energy Team..update
To: autox@hoosier.utah.edu

I have received a few inquiries about the Energy Team and one request by Ned Kavanagh to post a quick description regarding it. First off...I am in no-way connected with Jacobs...receive no monitary compensation from them....etc...I gain nothing from this ... 'nuff said

The system was described by me in GRM in the Jan/Feb 1991 issue..pg 40..(quiz later)...

Bottom line is this..the system has 4 components: a computer control module, a high voltage coil, a three-way switch, and high performance plug wires.

The stock coil is replaced by the Jacobs coil. Attached to the coil by way of insulated mounts are the stock coil power and distributor/tach wires. These wires then go to a three way switch which allows you to use the stock ignition system, the energy team, or have a "kill switch".

The energy team computer senses the resistance in the spark plug when it fires. Aparently resistance in a plug at time of firing is related to combustion efficiency (hey, I'm no rocket scientist..)..given that tid bit, the computer then adjusts the duration and voltage the spark plug will receive the next time it fires to an optimum amount

This process is done a couple of thousand times per second. The effect is that the engine runs more efficiently, ie more power....it cured a slight bog off idle in my VW as well as a high speed miss. Both were caused by an incompatibility between the Webber big throat throttle body I used and the Bosch Injection system at the low and high speeds...

TIme-wise, at my "test course" I was running average times in the area of 96.827 seconds pre energy team...after installation time dropped to 95.595 ave...1.232 second drop or 1.25% drop in elapsed time.

If you want info call them at 915-685-3345 ask for Anita who was my contact there.

The system should work well with any spark ignition internal combustion engine - ie> rotary

ric golen

Date: Thu, 10 Oct 1991 12:32 EDT
From: RGOLEN@umassd.edu
Subject: Jacobs, The last and final word
To: autox@hoosier.utah.edu

May this be my last and final word about the Jacobs ignition system. I have received lots of comments regarding my description on how it works, and how my description seems at best improbable. Ok, here it is direct from a publication available from Jacobs, direct from the inventor himself:

"As explained above, the computer knows what the spark resistance is because it's using the coil as a transformer and spark resistance relfects back to the computer's connections at the coil primary. The action goes like this:

1. The computer senses the second drop in sparkplug gap resistance and turns on its computing section.

2. The computer senses the spark resistance and current.

3. The computer computes what the ideal spark current shold be.

4. The computer compares the ideal current computed in 3 to the actual current sensed in 2. For example, say the ideal current was 35 milliamperes, but the actual current was 120 milliamps.

5. The computer adjusts its drive to the coil to deliver what it "thinks" will be 35 milliamperes. The reason it can't know exactly is that as you change spark current, there are also other changes in teh spark gap occuring simultaneously. Variations in fuel, air moisture, temperature, piston position, and so forth, change the spark gap resistance.

6. Once the drive is changed it goes back to 2; that is it computes in a circle - 2 to 3 to 4 to 5 and then back to 2. Now suppose the spark current came out to 39 milliamperes instead of 35, but the new ideal was computed to be 48 milliamperes. The computer would again quickly change the drive to the coil to "target" 48 milliampers.

The reason the computer works so well is that id words of fast - 33 adjustements or cycles (2 to 3 to 4 to 5 to 2, etc) in 1.5 degrees of engine rotation. In most cases, 11 to 18 adjustments light those horses off every time.

Once ignition occurs, all spark gap conditions change drastically. Instead of the coil pumping current into a high resistance air/fuel mixture, its suddenly pumping through a burning plasma. A plasma is any smooth liquid in which there are suspended particles...In a combustion chamber, plasma has abundant free ions and electrons and therefore low resistance. The spark gap resistance drops from 100k ohms to about 1k.

This is the second drop the computer is looking for. For 50 microseconds after it senses this second drop, it continues to pump a maintanance current into the gap. It does this to assure that it hadn't misread the start of the ignition process.

After this 50 microseconds, it "reverses" the drive on the coil. As the computer was driving the current in the forward direction, it was simultaneously counting (count-up) how much current went through the gap. It now pulls this exact same current back out in the reverse direction (count down to zero). The primary purpose of this is to re-deposit metal on the spark plug electrodes....

This reversing action also demagnetizes the coil, as a permanently magnitized coil looses its spark output in direct proportion to the strength of the magnitization.

The voltage polarity on the wire's insulation and rotor is also reversed. This re-scrambling of the insulator's molecular structure keeps their properties intact. (Its the alignment of the insulator's molecules that allow current to escape) In a non-computer ignition the voltage sparks are all in the same direction, leading to extra stress of the high-voltage insulation and its more rapid deterioration. Once the computer has counted back to zero, it stops and waits for the next input command from the points or amplifier."

Thats it, direct from the horse's mouth. And now to quote John Lennon: "I GOT BLISTERS ON MY FINGERS!!!!!!"

ric golen

From: Brian Kelley <dgsi!brian@sharkey.cc.umich.edu>
Date: Thu, 10 Oct 91 11:46:50 EDT
To: RGOLEN@umassd.edu
Subject: Jacobs Energy Team
Cc: autox@hoosier.utah.edu

Ric Golen writes:

>I installed it in the car, the times decreased, some
>other benefits were the end of a low-end bog problem, as well as the end
>of a high speed missfire.

I would really like to see it compared to an MSD unit. From my (and others) experience the MSD has a similar effect. I wonder how they compare in cost? MSD has been around for a while, so I'd be inclined to put my trust and ($$) in them.

These ignition systems REALLY help out if you run a car with a radical cam that doesn't like to idle or do anything down low. I'll probably be buying an MSD unit later this Winter, unless this unit is better.

Brian

B-30/20 timing problems

Date: Wed, 12 Feb 92 00:28:18 EST
From: Alec Isaacson <AI4CPHYW@miamiu.acs.muohio.edu>
Subject: B-30/20 timing prob
To: Volvo Owners Mailing list <volvo-net@me.rochester.edu>

Well Gang, I fixed it:

As many of you may have seen over the past several months, I was doing battle with the Fuel Consumption Problem that Ate Oxford. It is now my pleasure to announce that once again, humans are victorious in the great battle against those machines that try to make us prematurely grey. The following is the story of our hero, (the man with the metric ratchet set) and a cautionary tale for those who follow after.

My 1972 Volvo 164E with the 6 cylinder B30F, D-Jetronic fuel injected engine was suffering from horible fuel consumption (~130 miles per 15 gallon tank). The spark plugs were dry fouling so bad, that I was using two sets of plugs, one in the car, and one being cleaned (Saturday was swap day). I messed with the fuel system's sensors, wires, and injectors for about 2 months and found no faults. Finally, I gave it up and took the car to a mechanic, who, after two days, diagnosed the problem as a bad distributor and driving gear (that's the gear that connects the camshaft and the distributor). He said that he could get the parts in about 2 weeks and do the work for about $300 (about what I paid for the car).

Being an intrepid mechanic myself ("I can work on a foreign car, I have a metric screwdriver") I retrieved the car from the professional and decided to do it myself. I found a rebuilt distrib for a pittance and installed it. The car ran horribly (it acclerated like a wounded, elderly, Swedish Waterbuffalo). To make a long posting shorter, I found that the vacuum advance just wasn't advancing. I got under the distrib cap and sucked on the vac advance hose while watching the breaker plate. It moved. (Someone told me that this means I am amazingly talented :) ) So I checked the fitting on the intake manifold. Jackpot!! A rather large piece of toxic car mung was plugging the pipe. I did a hazardous waste cleanup on it, reset the timing (15 deg BTDC) and the car now runs fine. Once again my Volvo and I can beat dump trucks in drag races, zip up and down the highways and byways of rural Ohio, and rob banks without having to worry about foot patrolmen catching us (all without a gas bill that resembles my tuition payments).

I would like to thank all of you who responded to my cries for help (the in-famous "Timing Question" series). I do, seriously, appreciate your providing me with the benefit of your expertise, and hope that I can do the same sometime.

Fixed the bad idle problem with my B-23

Date: 08 Feb 1993 12:20:41 -0500 (EST)
From: V093P9MD@ubvmsb.cc.buffalo.edu
Subject: idle, bad, B-23
To: swedishbricks@me.rochester.edu

I finally solved my bad idle problem this weekend in the '84 240 (118,000 miles). After a lot of diagnostics I replaced the constant idle motor... it seemed OK by measuring it, but it appeared not to work 100% right. Since I recently pulled one from my '85 740T (88,000 miles), and it solved the problem (later took the thing appart and saw the design flaw. There are three contact points in the "base" of the unit that carry the electrical curent to the coil, which causes the valve to turn, eg. a basic DC electrical motor. The problem is that it moves back and forth a lot and the contact points grind a crove and pits into the contact service causing the eventual mal function). In the 240 the air control valve had been replaced by the dealer at 50,000 miles, so it wasn't too old yet. After replacing the unit and disasembling this one it looked OK, no severe scratches. Two days later the car didn't want to start...someting had finally really stopped working... maybe it could be located? It turned out the the ignition wire from the distributer to the coil was sparking at the coil end, by passing the coils internal "stuff." After throughly cleaning the coil the poor idle seems to have ended!!! It only took one year to find! It musty have been causing poor voltage to the spark plugs only at certain humidity levels therefore the irradic problem (working great one day... crappy the next). So check those coils and be shure their clean!

(sorry for the long posting, I guess I tend to ramble on a bit at times)

Troubleshooting ignition problems

To: ah301@yfn.ysu.edu
Cc: swedishbricks@me.rochester.edu
Subject: ignition trouble shoot..
Date: Mon, 08 Mar 1993 09:11:02 -0800
From: Rick Farnbach <fsf@wv.mentorg.com>

>>>>> On Mon, 8 Mar 1993 08:25:47 -0500, ah301@YFN.YSU.EDU (Jerry Sy) said:

Jerry> I was coming home from cleveland to pittsburgh yesterday and running Jerry> around 65 to 70 mph, then all of a sudden, the engine stopped turning Jerry> (rpm dropped to 0). I was able to pull to the shoulder from the Jerry> momentum left in the car. I look for obvious damages (belts, fuse,etc) Jerry> but can't find any. I tried starting the car, the first couple of times Jerry> it was cranking and turning the engine, but not starting. Then after Jerry> that, the engine won't even turn anymore. I'm sure I've still got Jerry> juice in the batteries and it can't be the alternator because the Jerry> engine death was sudden. When I turn the keys, I can still hear all Jerry> the fuel pumps sound. Jerry> any ideas what this could be ? could it be the timing chain ? Jerry> could it have damaged the valves ?

Not likely the timing chain, though it is quite simple to check by removing the valve covers.

When an engine kills itself suddenly it is usually an ignition problem. Fuel problems usually cause the car to buck, run rough, or sputter just prior to killing the engine. To verify an ignition problem, hook up a timing light around the high tension line from the coil and try to start the car. If the timing light doesn't flash then it is an ignition problem.

The most likely cause of a killed ignition is a bad sending coil in the distributer. There should be a wire going from the distributor to the ignition control module, with a two wire connecter about half way along its length. Disconnect this plug and measure the impedence between the two terminals on the distrbuter end of the wire. What you are measuring is the resistance of the pickup coil in the distributor sender. I can't remember if you should expect 600, 900, 690, 960, or what. It probably doesn't matter since if the unit is bad you will either get >>1K (open) or 0. If the sender is bad, it is often cheaper to replace the entire distributor with a rebuilt one than to get a new sender. If it's between 600 and 1K ohm I would look elsewhere, such as the coil or the ignition control module itself.

The coil is also tested by measuring its impedence. If the distributor sending unit isn't the problem let me know and I'll look up the test procedures for the coil. The ignition control module is tested by measuring the voltage on a couple of pins. More on that if needed.

Changing the heat range of your spark plugs

Date: Thu, 29 Apr 93 14:06:22 EDT
From: 29-Apr-1993 1359 <corey@cthq.enet.dec.com>
To: swedishbricks@me.rochester.edu
Cc: corey@cthq.enet.dec.com
Subject: Spark plug heat range

Changing the heat range of your spark plugs will not make the engine run any cooler, nor will it affect the exhaust output temperature. Heat range in plugs is mainly determined by the length of the center electrode porcelain insulator. Hotter plugs have a longer insulator and the plug will run "hotter" since the heat on this center piece has a longer route to travel to the metal section of the plug and then the block. Plugs with a hotter heat range are good for short trips and stop and go as the retained heat -in the plug- help to keep them from fouling. Colder plugs have a shorter ceramic insulator around the center electrode and thus transfer heat quicker to the the metal portion and the block (cylinder head). Cold plugs are good for high speed driving or severe conditions (racing) as they are (from my understanding) less likely to cause detonation. Factory recommended plugs represent a compromise based on the fact that you will usually drive a mix of city and highway.

By the way don't assume that a lower number on a plug means it is a colder plug. Some mfgs are just the opposite.

What causes my engine to ping?

Date: Mon, 22 Jun 92 19:48:07 EDT
From: Tim Takahashi <tim@me.rochester.edu>
To: swedishbricks@me.rochester.edu
Subject: Pinging.... (was Re: Rough Starts)

On Jun 22, 4:25pm, "Y. Alan Wang" writes:

> When I first got my new 84 245, it takes me no time to know I have to put
> premium 92 octane fuel. > I found one condition (where) it still pings(,) which > is after picking up speed between 40 and 50, loose up the gas pedal > and apply it lightly to maintain the speed. IT PINGS. > Anyone can explain? If I put the gas padel a little bit harder, no ping.

Pinging is caused by uneven combustion in one or more cylinders. Generally the is caused by a "hot spot," something like a carbon deposit in older engines or just the residual heat of the spark plug electrode. Pinging gets worse when the "octane number," an indication of the resistance of the fuel to resist spontaneous combustion, is insufficient for the conditions at hand.

Advanced (early) spark, warm weather, previous "pinging," higher effective compression ratios (either the static compression ratio of the motor, or due to manifold vacuum) tend to make the motor run hotter.

The spark advance is, in part, controlled by the engine manifold vacuum. At light load, the vacuum is high, advancing the spark more. Under these circumstances, your motor "pings." By depressing the pedal slightly more, the manifold vacuum drops, and the spark is advanced less. In your case this will eliminate the pinging.

I would suggest trying the next cooler heat-range spark plug if this is a persistant problem as a start.

BTW : my v6, which does not have much of a pinging problem, pings at high rpm (over 4000rpm, under high engine load on warm days). In other words, if I want to cruise the Macdonald-Cartier southwest of Toronto on a warm, summer day at prevailing speeds (80+ mph), I had better fill up with with 89 octane!

Can you tell if an ignition module is about to go out?

From: alfred@nyquist.bellcore.com (Alfred Kwan 21342)
Subject: Re: died!
To: quadrun@jhunix.hcf.jhu.edu (Jason G Velasco)
Date: Thu, 13 May 1993 10:34:48 -0400 (EDT)
Cc: swedishbricks@me.rochester.edu

Jason:

> Question is, is there a way to tell that something like that is about to
> croak? Or is the only way to be sure is to carry a spare ignition module
> and distributor(!)? It seems things like that go after you get somewhere in
> the 125-150k mile range, and I worry cause my car has 117k now, and I was
> planning on taking lotsa road trips this summer...

I had an ignition problem on my 1980 242 around 170K. The car just died at random, in the middle of Holland Tunnel no less. It won't re-start when the engine is hot. Once the engine cooled down, it started right up. It turned out that the ignition pickup coil in the distributor was bad. I was able to buy the coil from the dealer and not have to replace the distributor. The distributor must come out and taken apart to replace the coil.

Alfred

Date: Fri, 14 May 93 08:42 EDT
From: <mm@schunix.dmc.com>
To: quadrun%jhunix.hcf.jhu.edu%uunet@lectroid.sw.stratus.com
Cc: swedishbricks@me.rochester.edu
Subject: ignition died!

Ignition components other than spark plugs, cap, rotor and wires, aren't maintainence items.

However, we all know that nothing lasts forever.

On my brick, the first thing I did when I bought it with 130k on it was change the coil (along with about $500 in other engine parts). I don't trust any coil that has over 75,000 on it, an in particular, ones that are part of high energy systems that use large spark gaps. FYI, I just worked on my sister-in-laws SAAB 900 with K-jet and it uses a .025" gap on the plugs! Compare that to almost double on some other cars (my brick gets .044).

In bricks with Chrysler distributors (I think around '82, don't know that exact years), the "pick-up" unit of the Hall Effect distributor system should be replaced every major tune-up. I had this piece of crap in my 1978 Plymouth Whore-Eyes-On and it failed like clock work about every 30k. Peice of crap. That car also had problems with the ballast resistor. Bricks generally don't, but I always replace that with the coil. In my opinion, with a correctly maintained ignition (plugs, rotor, cap, wires) you shouldn't need to do the coil, pick-up (if you have it) or control module more than once, say at like 75-100k.

The control modules don't usually fail completely by the way, or at least they don't do so without warning, usually rough idling (misfiring that sounds like a bad plugs, wire or valve) or weak/yellow spark.

What is a Color Tune kit and where can I get one?

From: southern@neit.cgd.ucar.edu (Lawrence Buja)
Subject: Re: color tune
To: swedishbricks@me.rochester.edu
Date: Fri, 1 Oct 93 12:43:08 MDT

Dirk de Boer writes....

{Someone on the net mentioned clear glass spark plugs for observing
{the color of the combustion process in the cylinders. Anybody know
{a source for these? I looked in the J.C. Whitney catalogue, but could not find
{them. There is a brand of these called Color Tune, right?

You've got the name right and they're a sweet tool to work with. And yes, you actually see the color of the flame in the cylinder.

I borrowed one from a friend a few weekends ago to tune the twin SU's on my Daimler and the twin ZS's on a friend TR-6. It's basically like the bottom part of a spark-plug with a transparent material used in place of the usual ceramic. Then there's a wire to which you attach your sparkplug lead. There's some other bells & whistles with it like a tube with a little flexible mirror on top so you can see the color when you are on the other side of the engine.

When you see a yellow flame, the mixture is rich blue flame, the mixture is lean/OK

They caution you not to use these on the road.

The Roadster Factory (a great british-car parts place) in western PA carries these. I don't have their number, but they always run ads in the back of Road & Track. If you need their number right now, it's in the parts-places list on the british-cars anonymous ftp archive at hooser.cs.utah.edu:/pub/sol

/\ Lawrence Buja Climate and Global Dynamics Division
\_][ southern@ncar.ucar.edu National Center for Atmospheric Research
\_________________________Boulder,_Colorado___80307-3000__________

From: jjoy@akamai.sps.mot.com (Jennifer Joy)
Subject: ColourTune info
To: swedishbricks@me.rochester.edu
Date: Fri, 1 Oct 93 13:50:00 CDT

Well, I still find the brit-car list an amazing source for stuff. They know about twin SUs, too. (Funny how they never seem to work on MGs, and work so well on Volvos ... :-)

jen

(who is constantly amazed how packrats can produce lots of info while knowing nothing at all!)

Here's one source for ColourTune (note it was on sale then, that was in June!)

Date: Mon, 7 Jun 93 08:10:42 PDT
From: "GERONIMO, SC9-32, 765-4903, PAGE 231-6612" <GENDIMEN@T12SYS.intel.com>
Subject: ColorTune Kits

Someone on the list last week was asking about where to buy colortune kits. I got the weekly special flyer from TRF with my order last week. Among other things, the colortune kit is on sale for $32.50 (reg $44.50), P/N GUCT500, mention weekly special sheet Vol 1, No.13 when ordering.

Mike G.

OH, TRF is a place for Triumphs (and MGs):

--------------

Roadster Factory
The Roadster Factory (aka TRF)
PO Box 332
Armagh PA 15920
814-446-4444 (Note: 2% discount on phone orders.If you buy, they pay for the call)
800-678-8764