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Glow plug diagnosis help.
Current symptom; when I turn the key to the run position, the dash glow plug light does NOT illuminate, nor does the solenoid on the back of the driver's side head click. Step one in everything I've read is to start with the fuse, but I cannot locate it. Any guidance on where I will find it? My fuse panel beneath the dash is old and I cannot make out what should be what down there. However I am not seeing any 20a fuses which are burned-out.
Thanks
While searching for the glow plug fuse, I went ahead and followed the wiring and controller testing procedure and come to find out that the controller is showing too much resistance on the 2 - 3 pin test (reading 1.8ohms, spec is .4 - .7ohm). So looks like the controller needs to go.
Just fyi, Ive been running my blazer for 3 years without a controller. I use a momentary button to run the relay when I need it. This engine is very strong and will start with no glow time about 50% of the time in moderate temps.
Also might want to ohm out the GPs while your in there.
Given that this is my daughters vehicle, I am trying to make its operation as simple as possible. Teaching her about how glow plugs work has been enough of an effort, teaching her now that she needs to learn to use a new starting technique (momentary switch) is just going to confuse/frustrate her. So as with the OEM lift pump, I am going back to as much of the original design as possible and upgrading only those things where the operational impact is minimal.
I do appreciate the suggestion, but there will come a time where she will need to manage this thing herself, and I don't want to spend my days explaining to her over the phone from wherever she is broken down how we kajiggerred her TPS so she needs to explain it to the tow truck that picks her up. I've got that kind of confidence in my knowledge, but if I'm not around she needs the machine to be as close to the original textbook as possible. I am trying to teach her about mechanics, but she really has no interest and just needs this thing to work.
There were two different glow plug controllers. if you look in the books or do a search you will find the change over year. the newer style is the one to go with. I think the year was 1986 that the newer style started.
I agree 100% in the KISS theory....
I thought the newer controller required relocating the controller? Seems like a lot of the advice is written for suburbans & C-series trucks as opposed to the skeevy pedo-van. :D
Any recommendation on which manufacturer to go with or stay away from? I've chased hell on O2 sensors buying cheap ones (niekon or some such) as opposed to proper Delco, so I am willing to pay a little more for a better quality unit.
Yes, Delco is preferred. Rather than replacing what was original, do yourself a favor and upgrade to the 1985+ controller and inhibit switch (temp sender). More simple and more reliable. It's also a good idea to install a manual override for either system, for when it doesn't want to play nice. It's as simple as adding a momentary switch/button (in the dash) to apply 12V to the small pole on the relay.
Well I am trying to get a hold of Kennedy Diesel to get some info on the controller upgrade kit they sell. Hopefully I can release an order today or tomorrow, I really want to get this thing running again. :(
Whelp, Kennedy has a new controller upgrade kit heading my way. Looking forward to breaking out the soldering gun and making this baby rattle again. At least, assuming the lift pump is working. And my fuel tank isn't completely contaminated. And my injector pump isn't shot. Baby steps...
I would make sure that you have a clean known fuel source.
Yeah, I've got a spare boat tank and as much as I don't want to risk air getting in to the system and have to bleed the injectors again, I guess I need to remove the rubber feed line from the lift pump and drop it in to that tank filled with some new diesel.Quote:
Originally Posted by Dvldog8793
Take it from me, while in a truck or suburban there might be easy access to the injectors and glow plugs, in the van that doghouse tunnel makes air bleeding a royal PITA.
So I am installing the upgraded glow plug controller from Kennedy and came across a wiring anomaly. The switched power wire to pin #3 on the original controller is a very pale blue, to the point that I mistook it for light green. Anyway, that wire goes to the old relay (which I am removing) into a two prong plug, the other wire in that plug is pink. With the OEM relay removed, I checked that pink wire and it has battery voltage when the key is in the run position. The blue wire is dead. According to the instructions I received from John Kennedy, I need to tap in to that blue wire on pin #3 to a given terminal on the new relay/controller, but if I am not mistaken that will do nothing. I should connect that pink wire, is that right? This sounds obvious in my head, but I want to double check.
Also, I keep putting off removing the rubber line to the lift pump and running a new line to a spare fuel tank with new fresh diesel, mainly because I don't want to bleed air from the injectors again. But from reading, will I actually have to bleed air that way? I thought you only had to bleed the injectors if you got air between the lift and injection pumps (like when you replace the secondary fuel filter)? Its not the end of the world to bleed them, but it is a royal PITA in a van.
Thanks for your responses.
Howdy
In the 6.2/6.5 diesels that I have owned over the years and working on them in the USMC....I have never cracked a line to bleed air. Maybe I'm lucky....:rolleyes:
I have always just cranked to bleed air from the system through the injectors. Most of the time it takes about two cycles of 15-20 seconds and they are running.
Also I have never had the misfortune of have an un known air leak in the system.
I don't think you'll have to injector bleed the system. pinch the hose with a visegrip and take it out.
good luck...
Check with Kennedy for wiring questions on the controller, if it isn't OEM. If the controller is a simple 1985+, it should have Batt+ to one large pole, the other large pole goes to the GP's or GP harness, and Ign+ goes to the small "S" pole (just like on a starter solenoid). If it has a 4th pole, that is for the inhibit switch (coolant temp switch). Either way, confirm what you have with Kennedy.
You should never have to bleed the injectors if there is no air between the IP and injectors. Prevent this by removing the pink/power/front wire from the IP while messing with the fuel supply. Don't plug it back in until the rest of the system is bled. If you this, only minimal air will have to pass (most out the return), which will be negligible. The short route between the final filter and IP is only a small amount, but shouldn't have air in it unless you pushed air to the IP from the filter.
I am waiting to hear back from Kennedy re: the wiring questions.Quote:
Originally Posted by DmaxMaverick
Thanks for confirming my thoughts on the air bleed. I initially replaced both filters and had to bleed the air at the injectors due to the secondary filter downstream of the IP, then when I replaced the lift pump along with all of the rubber fuel lines from the lift pump back to the tank, I went ahead and bled them again figuring that with the line between the lift and IP being open air would've gotten back in. If I don't have to do it again, that would be awesome. Time will tell.
Thank you again.
There is no filter downstream of the injection pump. As long as you don't PUSH air to the IP, there should be no air at the IP. All air bleeding should be done, finally, at the final filter immediately before the IP. Opening any of the filters to air will not allow air into the IP (or the injector lines or injectors. Disconnecting the IP inlet solenoid (ESS) connector prevents any air from entering the IP, as long as it is not reconnected (and cranked) before all the air is bled and the system is closed.
I got ya, sorry for my confusion, I don't think it clicked that the secondary filter is fed directly off of the lift pump.
Anyway, back to the controller upgrade. There is an article in volume I of the diesel book on this site which details how to accomplish this upgrade. Speaking with John K earlier it sounds like this would give me a clear shot at completing this upgrade, would anyone be willing to shoot me a copy of it? I am not opposed to buying it, and if that is the case then so be it, but since I only need the one article that would be very helpful. I bought the troubleshooting manual from the library, but it only describes how to diagnose/repair the OEM systems, not cross over between the two.
Thanks.
I recommend buying the TDP books relevant to your rig. The systems you've already encountered will be covered in detail, including the "crossovers", which should simplify the process. If you intend to continue DIY, it will also cover issues you will encounter later. If you are a TDP subscribing member, many of the past articles are available in the Member's areas of TDP (not the forums). Some may be made available upon request.
Looks like I figured it out, using the wiring diagram for both controllers. The cycle time is really short, and I guess I am still chasing a fuel issue from this point because it still won't start.
Fuel system checks out, gotta be the glow plugs not having enough time to heat up with the new controller. So close!
New GPs should be here Thursday, I know what I am doing this weekend.:D
Can you time the controller and tell us how long its running?
Also if you want to try something....Take a can of air duster and hold it upside down and spray the base of the controller. This should fool it into thinking that it is about -10 out and would make sure that the controller is functioning.
What glow plugs did you get?
When I got it hooked up, it seemed like a cycle time of less than 8 seconds, followed by a 10 second break then another 2-3 second heat cycle. I will time it correctly next time I am in the cab. Interesting idea about chilling the controller.Quote:
Originally Posted by Dvldog8793
I got the quick heat plugs from Kennedy.com.
The cycle timing sounds normal. It was originally designed for 6V fast glow plugs, such as the AC9G and AC11G. This can present a problem with later plugs, such as the AC60G, which is a much more durable plug, but is much slower and may require longer glow cycles. Many claim they are fine in their rig with original timing, but I think they simply have an easier starting engine, or are using them in a favorable environment. Voltage and heat are what they are. The Kennedy QH plugs you bought should work very well (I use them). They are very fast and very hot, similar to the original 9G plugs, without the concern of premature burn-out and swelling.Quote:
Originally Posted by Bigshankhank
I sprayed PB Blaster on them last night in preparation for the new plugs arriving for this weekend. Do I need to coat the new threads in copper anti-seize? Pretty typical for spark plugs on a petro engine.
Definitely use anti-seize on the GP threads. Be sure to clean up the PB Blaster and anything else remaining once the old plugs are out. Brake cleaner works well (let it dry thoroughly).
Thanks, just wanted to make sure.Quote:
Originally Posted by DmaxMaverick
When you put in the glow plugs make sure the connectors are tight and not heat damaged, they should be a high temp type of connector and should fit tight. Just another common problem, especially if someone has been re-working the electrical.
Good point. If they've been replaced with common plastic covered spade connectors, they don't last long. I've used them, but plan on replacing them much more often. They are made of thinner/weaker metal and the contact becomes questionable after the many heat cycles. Heavy duty silicone-covered connectors are as good as ceramic or high-temp plastic (Bako-lite, IIRC).Quote:
Originally Posted by Dvldog8793
Better connectors, I guess that's next. The new GPs showed up and lo and behold all the original 9G plugs came right out, no breakage. Once everything was back in and snug I tried again to start it to no avail. I got a little sputter on the first attempt to start, but after that each interval with the starter it just spun the engine till the battery weakened a bit and I gave it a rest. The connectors are probably the originals, and they slip on and off fairly easily, so I really hope that is it. Never really noticed ceramic spade connectors at Autozone or Napa, where's a good place to get them? Going through the book I feel like I have checked everything, pumps, controller and relay and now plugs. What else am I missing? At 62k miles I hope like hell it is not a compression issue because we don't have enough enough money in this thing to justify an engine rebuild.
Maybe should have said this BEFORE you got the new GPs. One way to verify that you are getting fuel to the cylinders is to turn it over with the glow plugs out and verify fuel mist from each cylinder.
These engines need three things to run: compression, fuel and air. I would just start to verify those. Your glow circuit sounds good and is only involved in starting. Another way to verify the glow circuit is with a clamp-on amperage meter on the main feed wire.
I DO NOT like it, but it is possible to get it running with ether. I have done it with my 1986, it has a manual glow plug system. If you decide to try to get it started with ether....remove all power from the glow plugs and use a 50% ether. Personally I would try to verify that you are getting fuel to the cylinder before you try the ether.
I have never seen the ceramic connectors over the counter. You should be able to find a good quality high temp/heavy duty female connector at a REAL parts store. When I replace them I solder them on with a high temp solder.
Are you getting smoke out the tail pipe when it turns over?
I am getting fuel from the injectors when I loosen them and turn the engine over, I will pull a couple of the plugs and see if I get a proper mist.
I tried ether last week prior to replacing the GPs, though I did not disconnect them. It started momentarily but made a terrible rattle so I did not continue using it.
Haven't looked at the tailpipe when trying to start, I'll turn around and look next time,
Thanks.
FYI the GP controller bracket I had to fabricate.
http://img.photobucket.com/albums/v4...psbnckfmz3.jpg
Old glow plugs
http://img.photobucket.com/albums/v4...psxkgqnuv7.jpg
Old vs new plugs
http://img.photobucket.com/albums/v4...psm2cgofzf.jpg
After cranking for 10-15 seconds you should see smoke from the tail pipe.
Make sure your batteries get charged up good every night before you start trouble shooting.
Never use ether without disconnecting the glow circuit.
If there is a lack of smoke, does that tell me I am not getting fuel? If not fuel, what is it telling me?Quote:
Originally Posted by Dvldog8793
Yeah, I've kept them on a trickle charger for the past few weeks while I've been trying to get it running again.
Good to know now about the ether, but I can't undo whatever I've done to it by this point. What does the ether do to the plugs, if I may ask?
If you are seeing fuel with the injector lines loose, but not seeing fuel spray with them tight (glow plugs removed), then the IP is questionable. It may be able to push fuel at low/no pressure, but unable to pop the injectors. The injectors determine the fuel pressure (the pressure they pop), but the IP must be able to produce that pressure. Air could also be an issue. Excessive air in the system, and continued introduction of air, can prevent the injectors from popping, due to the air cushion in the lines. If the injectors can't pop, they can't move fuel or air through the lines.
Ether and glow plugs don't mix. If the GP's are hot, the ether will ignite as soon as it is exposed to the GP. This can cause engine damage, as well as ignite back through the intake. I've seen air cleaners blown completely apart (too much ether probably had something to do with that). The heat of Diesel engine compression is enough to ignite the ether, so it will fire (that cycle) without the GP's. As said above, it is NOT recommended, under any circumstance if it can be avoided. It should ONLY be considered an emergency option. Always disconnect/disable the GP's before using it. Ether should never be used as a diagnostic tool. If you have a fuel delivery problem, work on that. Ether won't fix anything.
All good info, thank you.Quote:
Originally Posted by DmaxMaverick
According to the Diesel Maintenance book from the library here, testing the IP involves disconnecting the pink wire from the iggy relay and listening to hear the relay click. Mine clicks, repeatedly as I checked it several times. Just because the relay clicks though, does that mean it is pushing enough fuel at the right pressure? I guess I will test for spray this evening. Can they be rebuilt? Seems like when I checked Rockauto a replacement pump was on the order of $700.
When I replaced all the rubber lines between my tank and lift pump I did my best to crank down on the new worm drive clamps (I replaced the old clamps at the same time), so unless it has an air leak between the lift and IP which just manifested itself I don't think I have an air leak. I have not pressure tested the tank, that can go on the list eventually.
If your mechanical lift pump works (it should, it's new, right?), a leak between the LP and IP will be an external fuel leak, not an air intrusion leak. Conduct a fuel mist test (GP's removed, all injector lines tight). If all open cylinders don't mist fuel, install a length of clear tubing at the IP return outlet, loop it, and crank the engine. Any air going through the pump will absolutely collect in the loop. If you get air in the loop (after it's purged itself), you have a leak between the tank and lift pump. Pressurizing the fuel tank can be helpful finding it (no more than 5 PSI or so on an old tank).
Check Kennedy's site, and/or a local Stanadyne certified shop, IF it comes to the need of a replacement pump, costs should be similar, so also consider the customer service in the price. Run all the tests first, to verify a healthy or failed pump.
The "click" heard/felt at the IP when connecting/disconnecting the pink wire is the ESS (Engine Stop Solenoid, fuel solenoid, etc.). Clicking only indicates the solenoid is working. If fuel passes through the pump with it "on", and doesn't when it's "off", it's working just fine. If it doesn't work, it will either not allow any fuel and not start/run, or it won't close, and the engine will not stop when the key is off. Keep it that simple. If it's clicking, don't mess with it. The result can be a run-away engine (and a need of clean shorts).
****, one of the last times it ran the engine wouldn't shut off with the key turned and even removed from the ignition switch.