no start '89 6.2 burb

[pologuy14]

the engine started yesterday no problem. go out to start this morning & no start. not sure what the problem is. & i had a vehicle to jump start the batteries & voltmeter to check so batteries were charged
here is a list to go off of

she cranks no problem
glow plugs glow
fuel is getting to the ip
air is out of the fuel line
(i assume the ip is pushing fuel)injector lines pulsate

any other ideas would be awsome thanks.

[JohnC]

Crack one of the lines at the injector and see if fuel weeps out. Fuel, heat and compression are all you need. One must be missing.

[pologuy14]

how do i check compression on a diesel engine? i have done a gasser but im still pretty new to the diesel world

[DmaxMaverick]

how do i check compression on a diesel engine? i have done a gasser but im still pretty new to the diesel world

Essentially the same as a gasser. But......You'll need a Diesel compression tester. Most gasser gages don't go high enough, and can blow the gage if your compression is anywhere near where it should be. You'll also use the glow plug hole instead of a spark plug hole. Remove ALL the glow plugs during the test, and it's done with the engine near operating temp. Unplug the injection pump fuel supply solenoid wire (the pink one, toward the front of the pump), else you'll be pumping fuel into the cylinders during the test, and the cylinder you are testing may fire (big ouch). Crank it for several revs to clear the cylinders of fuel before beginning (after the plugs are out). Be sure the batteries are completely charged, and recharge as necessary to maintain consistent cranking speed. Crank it for exactly 6 puffs on each hole with the gage connected, and take your reading. If your compression is above 300 PSI at every cylinder, and they are all within 15%, the compression is sufficient for a well running engine, but above 360 PSI is ideal.

[pologuy14]

so if i cant get the engine started to get to running temp should i just do the compression test anyways?

[Edahall]

There's a large power wire that hooks up to the top of the injetion pump. Make sure there is voltage on that wire with the key on.

[DmaxMaverick]

so if i cant get the engine started to get to running temp should i just do the compression test anyways?

No. It's pointless at this time. Your no-start problem is something else. Either no fuel, or the glow plugs aren't heating. The compression should have no bearing on your current issue. If it started fine one day, then not the next, you need to find out what changed between the two start attempts. Something changed, and it wasn't the compression.

[Robyn]

Check to be sure that there is actually power going to the glow plugs.

Just because the glow light comes on does not mean that the plugs are working.

Pull a couple plugs out, make sure that there is power to the plug when the key is switched to on and the glow light is on. Test the plugs with a wire to the battery. The plug should glow bright red within 8 seconds.

There is a possibility that the glow plug relay is not working properly.

Keep us posted

I would not worry too much about the compression at this time.


Robyn

[pologuy14]

the owner before me put the glow plugs on a switch so i have to manually turn them on. i will check tomorrow when i get back home & post my findings on the glow plugs.

[DmaxMaverick]

the owner before me put the glow plugs on a switch so i have to manually turn them on. i will check tomorrow when i get back home & post my findings on the glow plugs.

You have three possibilities with this alone. Could be: you aren't glowing them long enough; they've been held on too long, and are burned out; something with the wiring/switch/relay has failed.

Depending on the plug brand/type, they may be more sensitive to glow times. If original type, or compatibles, they are likely burned up. They were fast heating, but burned quickly if heated too long. The latest OEM style plug is the AC60G, they won't burn up near as easily, but takes twice as long to heat (10-20 seconds). There are unbranded aftermarket plugs available at a fraction of the cost of good plugs, and it's anyone's guess as to how they act. The "Quick Heat" plugs from reputable vendors are generally good, heat fast (less than 10 seconds to full heat), and usually wear long.

At this point, you should check the plugs for continuity and/or heating ability. And, as Robyn suggests, check the circuit to be sure they are getting power, by whatever means.

[pologuy14]

ok so something shorted out on the supply side of glow plug controller so the light was coming on but not the plugs. havent had time to hunt down the short/faulty wutever:confused:. so tomorrow is dedicated to following looms of extra wires put in by the previous owner. also tomorrow i have recent wyotech diesel graduate:D coming over to help, we'll see if he can help start the burb.
so im curious about updating the injectors. i am the 3rd owner & the previous said that they r original @ now 218,000 miles. so what is everybody's choice on replacement injectors?

[DmaxMaverick]

With a bunch of "custom" wiring involved, all bets are off. But.....The original harness had a fusible link between the plugs and controller. That would be a good place to start looking, provided they are still in the circuit. Your "Wyotech graduate" should be familiar with this. If not, send him back to the school for a refund.

[Robyn]

Have someone turn the key to "ON" while you crawl up onto the engine.
Place your had onto the Glow controler while the helper turns the key on.

If the thing clicks and the light comes on but there is no power to the plugs then the controler is bad OR the fusible link is blown in the feed line to the plugs.


Its a simple circuit on these things. If it clicks it should power the plugs.

Use a volt meter and check the two heavy lugs on the controler. One should be HOT all the time the other should be hot only when the controler has clicked on and is sending power to the plugs.

If neither lug is Hot all the time then you have a +++ feed issue to the controler

The fact that the light comes on makes me suspicious of the controler.

Give it a go and let us know.


Missy

[JohnC]

Not sure about the '89, but I'd bet that if the light on the dash comes on it means the controller is working. Usually the light is powered right off the controller output. Check the fusible links and the plugs themselves, if you haven't already.

[pologuy14]

so the controller is working. 1 post has power all the time & the other gets power when the glows r turned on. each plug gets power also, i am not sure how much power because i only used a 12volt test light...

[DmaxMaverick]

While you are at it, check each plug individually. Unplug the spade connector on the plug and use your test light. Clip the test light to batt+, and ground the probe to the glow plug spade. If it lights, the plug is likely good. If not, it's bad. That simple.

[pologuy14]

1st off thank you everybody for lending support & opinion. so i got the big pig started 2day. we found out dilution is the solution. i filled a jerry can w/ good diesel & ran the fuel pick up out of the can. it started right up as soon as the air got pushed out. because i still had the stock fuel return line going to the diesel tank every time i ran wvo it put some oil in the diesel tank. so we let the engine warm up & put 3 or so gallons left from the jerry can in the tank & it started again right up. ran straight to the fuel station & filled up w/ 20 gallons of fresh diesel & we will see if she starts for me tomorrow...

[DmaxMaverick]

WVO??? You kinda' left out that part. The help would have been a tad easier, with that little bit of info. Do yourself a favor and fill out your signature, and please include a little line about using an alternative fuel, even if only on occasion.

[pologuy14]

i hadnt run wvo in weeks so i didnt think it would have been the problem. but it was the 1st time i let my tank get to so low... i now have a looped system so fuel will not go back into the main diesel tank again