Newbie Alert...lots of questions

[Lil'red]

Ready, ok, just bought '84 Chev c/k 20 4x4 with 6.2 and has turbo. Already love this thing, the truck is in great shape, but this is my first diesel. Both times I test drove I checked to see block was not hot, let glow light go, turned it over, started right up, almost no smoke. Owner said engine had about 60k and was boneyard motor. Since bringing it home I've had some touble starting it. Was I duped by starting fluid or something!!! After a week of slow starts I started running biodiesel, then changed fuel filter and it still has a hard time starting and when it does there is fair a amount of smoke. I can get it started after a few tries but I have to pedal it, and after a ten minute drive, I let it sit for half an hour, then when I try to start it up no glow plug light so I crank it and it just turns but won't start. Glow plug relay? My mail man, funny enough, watched me struggling to get it started and said he used to have a chev diesel and they had hard time starting it on a hill, had a hard time believing that, tanks are full too. Thanks for any help...Also any one know of good diesel mechanic in Seattle area, thanks again, great site, Liam

[Robyn]

The partly warm hard start is most likely due to the Glow plug inhibit switch.
Its at the rear top of the RH cylinder head. Unplug the plug and fashion a jumper and bypass the switch.
This will allow you to have glow plug function any time you turn the key on

Robyn

[Subzilla]

Try putting in a higher percentage of petro diesel and see if that helps the starting. I started making and using BD last summer but had been using a percentage of the stuff. A month ago, the weather warmed so I pumped in 100% BD. The starting times became longer and longer in both vehicles. I'm talking about 5 long cranks with pedal partially depressed before they would start and run. I started checking fuel filters, glow plugs, air in lines, etc. The light came on (in my head) and I thought maybe it was the BD. I don't know why it took so long to come to that determination other than denial it was my homemade fuel. When the tanks were low, I pumped in some petro. Starting improved greatly. I'm guessing the lower BTU's of BD in combination with some worn 260k mile engines attribute to this. So now I'm running about 75% BD and I can fire up in one crank. It's not quite as quick as 100% petro but I'm happy with my 75 cents per gallon.

EDIT: I just re-read your post. You said you put BD in after you started experiencing hard starts. Hmmm, anyway, the BD won't help it start better. Consider putting in a momentary push switch for the GP's. This is easy to do with the '84 as the relay sits right on the fender and is quite accesible to wire up to.

[moondoggie]

Good Day!

Do you know for sure what glow plugs (all 8 of them) are in your engine? If you aren't completely sure, be VERY careful with a dashboard-mounted glow plug relay control switch. If you have 60G's or Kennedy's glow plugs, you can glow (within reason) for whatever amount of time you want.

If you've got 9G's or 11G's, BEWARE. After an initial glow time of (I think) 7 - 9 seconds, simply cycle your glow plugs on 1/4 of the time. This is easy - count 1 - 2 - 3 - 4 & only hold your manual override switch on for one of the four counts.

Why? These are actually 6V glow plugs, which is why they only take a few seconds to heat up. The older ones (9G, 11g) will pop like a flashbulb if you exeed the 7-9 seconds by only a few seconds. Worse, when they fail, they might expand, making their removal, shall we say, problematic. :eek:

If you cycle a 6V glow plug in a 12V system so it's only on 1/4 of the time, for 1/2 - 1 second segments, it's gonna produce exactly the same amount of heat as if they were being fed 6V.

If you're not sure what glowplugs you've got, this proceedure should work fine with 60G's or Kennedy's, so you can't really lose.

Blessings!

[Lil'red]

Thank you all for your help, I'm sure I'll have more questions soon...