Glow Issues

owenjam · 11-02-09, 12:59 PM

http://forum.ih8mud.com/diesel-tech-...parts-usa.html

See above thread, advice needed. Started new thread since above thread does not mention glow issues in title.

Great info in this thread below from Lostmarbles and Henry about checking glow plugs.

Thanks

canucksafari · 11-02-09, 01:42 PM

Posted in your old thread.

lostmarbles · 11-02-09, 03:16 PM

Quote:

Originally Posted by owenjam

...See above thread, advice needed. Started new thread since above thread does not mention glow issues in title. ..Thanks

So you have a 3B engine that smokes (white smoke) and stumbles/misses when started cold! (Please correct me if I'm wrong here.)

To determine if you're running the right plugs, we need to know:

12V or 24V?

What type of glow system you've got:

Coil of wire mounted in the dash that glows orange (glow controller)?
"Superglow system" with its own automatic timers and an associated light on the dash? or
Just applying battery voltage direct to the plugs and counting the seconds in your head before cranking?

PS. - What voltage plugs are you presently running?

(Difficult to suggest other possibilities till we know you're plugs match your glow set-up.)

Henry James the 47th · 11-02-09, 03:24 PM

Besides the glow plugs, what shape are your injectors in? If they are worn and not spraying a fine mist of fuel, then your will get a lot of smoke regardless of how well your glow plugs work. It is a simple matter to have them bench-tested at a local diesel shop.

ukaviator · 11-02-09, 04:51 PM

Hey Owen thanks for bringing my thread over - I got a little off the beaten path from the original title!

Not sure what Owen is running, but I have a 12V system, using a push button glow plug system (counting seconds in my head!).
Injectors were rebuilt not too long ago.

Removed glow plugs and checked for damage, noticed 2 of them were slightly wet (not sure if its fuel or not) near the top - pic attached.

If the injectors were bad, wouldnt you get smoke all the time?
Only smokes like that in the Video the first start of the day.

lostmarbles · 11-02-09, 05:22 PM

Quote:

Originally Posted by ukaviator

...Not sure what Owen is running, but I have a 12V system, using a push button glow plug system (counting seconds in my head!).....

Well I'd expect to see 10.5V plugs for this set-up.

Quote:

..If the injectors were bad, wouldnt you get smoke all the time?
Only smokes like that in the Video the first start of the day.

Not necessarily.

Warmer cylinder temperatures tend to promote better-burning even when the spray pattern is bad.

Besides "poor-spray-pattern", "poor compression" is another possibility. ... And again - this tends to reveal itself through white-smoke/stumbling at "cold idle" (while at other times it usually shows up simply as excessive "blow-by").

Another reason for "compression problems" to show up more during start-up is because there is less oil on the cylinder walls at this time (to help the compression rings seal).

A "compression test" or "cylinder leakage test" can be used to check this possibility.

But personally I wouldn't consider other possibilities till I was sure all my plugs were working properly. (None open-circuited and all getting the appropriate voltage for their rating and for their type of glow-system.)

owenjam · 11-03-09, 07:58 AM

I am running the same system as UK as he described it. My truck has a full BJ60 harness and ignition switch, minus the super glow system. I used an aftermarket glow plug relay in conjunction with a wilson type set up. Turn key to illum glow light, hit button for 10-25 sec, then start. No afterglow function. I have 10.5 plugs in. Never smokes other than first crank of the day when cool. Temp range here now is 45 to 70 degrees F.

What about trying a hotter glow plug???

RufusTheDufus · 11-03-09, 09:30 AM

I found that the 10.5v plugs glowed too slowly in my 12v 1982 BJ42 with the factory glow controller (non-Super Glow). I switched to 8.5v plugs that are specified for my vehicle and they must not have offered enough resistance because I nearly smoked the wires to the glow indicator coil in the dash.

I had a set of 6v plugs for the later model Super Glow system so I figured I'd give them a shot. They work perfectly. Much better than the 8.5 plugs. I didn't bother to take them out to measure the resistance but they never get too hot like the 8.5s. The glow cycle takes about 8-10 seconds and the engine fires right up. I've got low compression to contend with too so the engine starts to stumble a bit after 5 - 7 seconds. A second glow cycle appears to cure it. Some day I'll get around to wiring a manual glow momentary switch into the circuit to be able to do an afterglow-like feature.

owenjam · 11-03-09, 10:43 AM

I happen to have a set of 6 volt Beck Arnley glow plugs. So you dont see any reason why I cant give them a try with my above mentioned glow system??? Wilson type set up with aftermarket glow plug relay.

Does the above picture UK posted of his glow plug look normal, worn, or bad????

RufusTheDufus · 11-03-09, 11:05 AM

The photo of the glow plug looks normal to me.

I'd give the 6v plugs a try but you need to be careful. The glow period should be significantly shorter. Do you have any type of visual indicator like the stock dash-mounted glow coil in your system? Does your system have a fuse to prevent you from frying the glow plug relay or some wiring?

owenjam · 11-03-09, 11:52 AM

I hold the ign switch in the glow position to illum the light and push a button to actually activate the circuit to glow the plugs. After the switch is turned on to run, no power goes to the relay.

lostmarbles · 11-03-09, 12:54 PM

I try not to get involved in discussions on cruisers fitted with "Wilson Switches" because I find it so hard to work out what type of glow system a person has really ended up with (once someone has tampered with the components/wiring). ......For example you can feed plugs directly off the battery (usually via a relay) or feed them via a "glow controller" (coil of wire on the dash that glows in unison with the plugs).

If you have a "GLOW CONTROLLER" in the circuit then this will be dropping the voltage to your plugs (because it is wired in series with "the parallel-connected plugs") and thus it should necessitate the use of lower-voltage plugs (compared to systems without glow controllers).

And not all glow controllers drop the voltage by the same amount for a given current flow. (For instance I believe there are different glow controllers depending on whether an engine is 6 cylinder or 4 cylinder.)

Without the "voltage step-down effect" of a glow controller, a 12V cruiser with "Wilson Switch" should normally run 10.5V plugs IMO. (And if they were to run lower-voltage plugs than that - I would expect them to run a high risk of burning them out.)

And I believe plugs that heat up faster (ie - lower voltage plugs) will draw more current (if the applied voltage were to remain the same). So I haven't a clue why 8.5V plugs would "smoke wires" when 6V plugs in the same situation don't! So Rufus's experience puzzles me - particularly since I believe 8.5V are the OEM correct ones for a "manual-glow with glow controller" 12V BJ42.

PS.

Quote:

Originally Posted by owenjam

...Turn key to illum glow light, hit button for 10-25 sec....

So what does this "turning your key" achieve? In other words - What is the glow light telling you and how is it helping?

I mean...you could have modified your glow system any way you wanted! Why didn't you set it up so you just push your button to glow your plugs (with maybe that "glowlight" coming on IN RESPONSE TO THIS so as to give you visual indication of "glowing") and THEN you could just turn your key to start cranking her into life? .....That way you could push the button whenever you like! - even while the engine is idling in order to "smooth it out" on a cold morning. (Sorry - I just don't understand the design of the system you have there.)

owenjam · 11-03-09, 01:11 PM

I do not have a glow controller in my system. I am going to test the voltage comming off the relay directly to the bus bar, since I am using an aftermarket glow relay for dodge diesels or farm tractors, there may be a drop in voltage as marbles was saying. I always assumed my cold start smoke problem occured due to the lack of after glow function, that the engine came with originally from Toyota. The harness I bought for my truck had none of the glow system intact.

RufusTheDufus · 11-03-09, 01:14 PM

Quote:

Originally Posted by lostmarbles

So I haven't a clue why 8.5V plugs would "smoke wires" when 6V plugs in the same situation don't! So Rufus's experience puzzles me - particularly since I believe 8.5V are the OEM correct ones for a "manual-glow with glow controller" 12V BJ42.

It baffled me too. I had no idea why the glow coil in the dash would glow bright red within a few seconds when I put those 8.5v plugs in. I put them in because the 10.5v plugs that were installed when I bought the thing glowed way too slowly. I saw 8.5v was the factory spec so I swapped them out. The only thing I can think of is the 8.5v plugs I used are much lower resistance than the 6v Superglow type plugs for the later model 3Bs.

There's a ton of cutting and splicing of my wiring from previous owners. It's possible something a previous owner did changed my system. I haven't verified if mine is actually wired up like a stock manual glow system.

lostmarbles · 11-03-09, 01:22 PM

Quote:

Originally Posted by RufusTheDufus

...The only thing I can think of is the 8.5v plugs I used are much lower resistance than the 6v Superglow type plugs for the later model 3Bs.....

If that were true it would go against what I've learnt (or thought I learnt

) Rufus

IMO the 6V plugs should draw WAY more current than the 8.5V plugs (when applied with the same voltage) - so this would make their resistance lower!

owenjam · 11-03-09, 01:29 PM

I have 11.5 volts at each glow plug head, right at full 12 volts on relay terminal going to bus bar. All glow plugs have continuity as well. Suggestions???

lostmarbles · 11-03-09, 01:35 PM

Quote:

Originally Posted by owenjam

I have 11.5 volts at each glow plug head, right at full 12 volts on relay terminal going to bus bar. Suggestions???

Have you removed the busbar and checked that each and every plug has "continuity"?

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PS. No need to remove the plugs. - Just remove the busbar and test between each plug terminal and the metal of the engine.

owenjam · 11-03-09, 01:44 PM

I did not remove bus bar when testing for continuity, not the most electrically inclined person. Can you remove the bus bar and test without pulling the glow plug? On a digital meter "Full Scale" would be "Zero" correct?

lostmarbles · 11-03-09, 01:57 PM

Quote:

Originally Posted by owenjam

I did not remove bus bar when testing for continuity..

You MUST remove the busbar and test each plug individually otherwise the test is completely invalid/pointless.

Quote:

..Can you remove the bus bar and test without pulling the glow plug? .....

Yes

Quote:

...On a digital meter "Full Scale" would be "Zero" correct?

Correct. .....or close to zero - In other words - a very similar effect (on the meter reading) to "touching both probes against one another".

owenjam · 11-03-09, 02:13 PM

Well, I have 2 glow plugs with no continuity. The first glow plug (front of engine) and the rear. Middle two test fine. Do you see a problem with swapping out the 10.5 v plugs with the 6 v or should I just wait until I can get my hands on more 10.5 plugs. What would cause the glow plugs to go bad in less than one year; I know that’s a tough question with lots of variables.

lostmarbles · 11-03-09, 02:29 PM

Quote:

Originally Posted by owenjam

Well, I have 2 glow plugs with no continuity. The first glow plug (front of engine) and the rear. Middle two test fine. Do you see a problem with swapping out the 10.5 v plugs with the 6 v or should I just wait until I can get my hands on more 10.5 plugs. What would cause the glow plugs to go bad in less than one year; I know that’s a tough question with lots of variables.

Replace all plugs as a set. (NEVER replace them individually.) And make sure all are in good electrical contact with the busbar.

If you run them straight off the battery (no glow controller) - I personally wouldn't recommend anything other than 10.5V plugs for a 12V cruiser.

Remember that plugs are prone to "cascade failure". So if one fails (or even has a poor connection with the busbar) - others are likely to fail as a direct result.

Causes? Who knows? I've never had a single failure in 30 years but some people are "serial killers" when it comes to plugs.

owenjam · 11-03-09, 02:36 PM

I would only swap them all or none. I just happen to have a set of 6 volt plugs I purchased on Ebay 2 years ago. I was going to change out all the 10.5v with the 6v. But I see you think thats not a good idea. I am sure UKaviator has a similar problem.

lostmarbles · 11-03-09, 02:44 PM

Quote:

Originally Posted by owenjam

I would only swap them all or none. I just happen to have a set of 6 volt plugs I purchased on Ebay 2 years ago. I was going to change out all the 10.5v with the 6v. But I see you think thats not a good idea. I am sure UKaviator has a similar problem.

I just think 6V plugs should draw more current and be more prone to burning out. But if you've already got them and don't mind the possibility of wasting them - go for it! (Just watch out for overheating wiring!)

And please report the result. (I love being made to reconsider what I think I know (ie - "being proved wrong!") - And this could well do it again!

)

Rufus's successful experience already opposes my opinion on this anyway.

owenjam · 11-03-09, 03:29 PM

Quote:

Originally Posted by lostmarbles

So what does this "turning your key" achieve? In other words - What is the glow light telling you and how is it helping?

I mean...you could have modified your glow system any way you wanted! Why didn't you set it up so you just push your button to glow your plugs (with maybe that "glowlight" coming on IN RESPONSE TO THIS so as to give you visual indication of "glowing") and THEN you could just turn your key to start cranking her into life? .....That way you could push the button whenever you like! - even while the engine is idling in order to "smooth it out" on a cold morning. (Sorry - I just don't understand the design of the system you have there.)

I guess the goal here was to ensure there was no way for the glow plugs to get stuck "ON" after the switch is turned on. Since driving the truck, I have considered changing this setup to fucntion like you said. Have a hot anytime you push glow button you can hit after cranking. I just might try the 6v plugs until I can order some 10.5v. I will report back.

RufusTheDufus · 11-03-09, 03:30 PM

I was curious so I went out and measured the resistance of my 8.5v and 6v plugs. The 6v plugs are from VSP, part number PT-146 and measure .3 ohms. The 8.5v plugs are from JKT and measure .4 ohms. I don't see a JKT part number on the plug. That's not much of a difference in resistance.

It's possible that the 6v plugs have a different resistance curve than the 8.5v. As a glow plug heats up the resistance goes up significantly.

The 6v plugs I have are for the Superglow system. Superglow provides two different voltages to the glow plugs during the glow cycle. I think it starts off with a full 12v from the battery and then steps it down through a resistor mounted on the intake manifold. The in-dash "glow controller" coil doesn't allow a full 12v from the battery to the plugs. It provides some amount of resistance. I wish I could easily get to it to measure the resistance across it. I'd like to do the math to compare the voltage to the plugs in the two systems.

FWIW, I don't wait for the glow controller to glow brightly with the 6v plugs. I start the engine before the glow controller is halfway in it's brightness spectrum.

owenjam · 11-03-09, 03:51 PM

So Rufus, about how long would you say you glow on average?

owenjam · 11-03-09, 04:28 PM

6 volt glow plugs are now in. Had someone hit glow button as I put my hands on the wire leading to bus bar and plugs themselves. Wire did not get hot at all, put my finger on #1 plug (where the wire attaches to bus bar) and 3rd plug at the same time. #1 plug is hot super fast, while #3 plug is a lot slower to heat up. What do you think? I measured 11.5 volts at each glow plug head. I will report tomorrow after first cold morning crank for accurate results.

lostmarbles · 11-03-09, 05:25 PM

Quote:

Originally Posted by owenjam

6 volt glow plugs are now in. Had someone hit glow button as I put my hands on the wire leading to bus bar and plugs themselves. Wire did not get hot at all, put my finger on #1 plug (where the wire attaches to bus bar) and 3rd plug at the same time. #1 plug is hot super fast, while #3 plug is a lot slower to heat up. What do you think? I measured 11.5 volts at each glow plug head. I will report tomorrow after first cold morning crank for accurate results.

I don't think you should feel any heat at all at the busbar connections if they were making proper electrical contact.

Heat there suggests high resistance in those connections (which could be caused by oxide on the busbar or paint/dirt or simply insufficient contact surface-area).

IMO the heat should only be generated at the plug tips (which are buried in the pre-combustion chambers).

I suggest you correct this problem ASAP to avoid the "cascade effect".

RufusTheDufus · 11-03-09, 05:40 PM

I wonder if the threaded holes for the glow plugs are corroded or not making good contact? If they are dirty/rusty/painted the glow plugs won't work very well.

My average glow times are pretty short with the 6v plugs, maybe 5 - 7 seconds. I haven't timed it. I just go by the glow controller coil.

owenjam · 11-03-09, 07:34 PM

I removed bus bar and cleaned each contact point on a wire bench wheel prior to re-install. I had my finger down on the side of the glow plug, not the tip where the nut is. One of my guys brought up the bad connection point as well, maybe remove bus bar and use wire. Now how in the hell do I fix it???? What would be safe to clean the inside threads with? Thats a good point Rufus about threads, not sure if I should go spraying brake cleaner down inside the combustion chamber however. From my observations, I have uneven heating from the front to back glow plug. That cant be good. And my #1 gp was bad where the wire connects, has to some correlation.