Hard starting....can you "flood" a diesel?..

[diesel4me]

My '85 Suburban has been hard to start,the first start cold it always gives a hard time..seems like it wants to fire up,but the fuel just dont want to ignite...I get a lot of smoke from the exhaust while cranking it,so I assume its getting enough fuel--if anything it seems like maybe TOO much?...the engine starts cranking and you can hear several cylinders "firing" but it just wont light!...if I use starting fluid it will fire right up,once it does it runs OK,and will restart easily once it has ran a few minutes..it acts like a gas engine that got flodded..

I have replaced a few glow plugs,it might still have a few dead ones,I haven't been able to get at the rear ones next to the A/C box to check them...the glow plugs are getting juice and I'd say at least 5 or 6 are working,if not all of them--they are wired to a manual push button..

the truck has an electric fuel pump on the frame near the fuel tank and the original lift pump on the engine has been by-passed ...someone also used 10 feet of 3/8" fuel hose instead of tubing to supply fuel to the fuel filter and injector pump...

The fuel tank was full last november when I got the truck,since that time I have ran it some and used some of the fuel in my diesel pickup,and it appeared to have no water or contamination in it--my other truck runs OK with it,starts OK too,but I didn't put much more than 2 gallons in it...

The previous owner told me the guy he got the truck from was planning to run it on biodiesel,so that is why it has the electric fuel pump and rubber fuel line (biodiesel compatible supposedly)...he also installed a Raycor fuel filter in place of the original primary filter..I dont see a secondary one under the intake,but thats not to say there is none,I cant really get a good look back there..I'd guess there isn't one..the trouble doesn't seem to be a lack of fuel though..

I have no idea if anyone did ever run biodiesel or any other home brewed fuel in it,the fuel I pumped out looked "normal",no grease or food particles,and the filter seems OK,not clogged up..It seems like the fuel just dont want to ignite enough to fire it up when its being started the first time of the day,regardless of temparature,though it did start reluctantly during the hot summer days.,had to crank it over for at least 30 seconds several times to get it to start---.now I have to give it a whiff of ether ,below 50 degrees..(and I hate to,I know what it can do to an engine!)..

Anyone have any pointers??..I want to get it to start easier ,before I burn up the rebuilt starter it has (A Delco non gear reduction one)...I dont see any fuel line leaks that would let air in either..
I'm hoping its not low compression or a bad injector pump,once it starts it runs fine,though it does have a slight misfire on the passenger side,so does my other diesel truck though..the cold start advance seems to work,it fast idles for about 4 minutes then drops down like it should..the injector pump timing might be retarted ,it acts a bit sluggish and the engine isn't as "rattle-ly" as my pickups engine is..could late timing cause this??....I've never attempted adjusting one so I am reluctant to mess with it..

 

[tRustyK5]

Almost for sure it's a slight leak in a fuel line letting a bit of air in, but not enough to leak fuel noticeably. I have the exact problem with my brown pick-up right now.

I had the same in my Black K5, turned out one hose clamp was slightly loose. I double clamped every connection and the problem went away.

For my brown pick-up the longer it sits, the harder it is to start. Let it sit 8 hours and it's only slightly miserable to start. Overnight, and it's a good bit worse...couple of days, it's a misery to get going again. It is less bad with a full tank of fuel.

All are symptoms of a slight fuel supply line leak.

Rene

 

[diesel4me]

I looked at it last night,and saw the fuel line at the filter housing that goes to the IP is waxy where the hose clamp is,but it isn't wet or a "fresh" leak...guess that could be the culprit,I'll try cutting the hose back some and re-clamping it..

Looks like I'll be re-vamping the fuel lines in my 82 K2500 too,they are extremely crispy,I'm surprised that truck fires right up--by all rights those flaky steel lines should be porus..I was thinking of using copper tubing to replace them,but I've read that diesel fuel & copper dont get along..I've used copper on gas engines with no trouble..got to do it soon before snow flies,I really wont want to fix them lying in a slush puddle..

 

[tRustyK5]

I think stainless would be ideal in your neck of the woods...and it'd be something you wouldn't ever have to deal with again.

Rene

 

[diesel4me]

It would be ideal,but not in my budget--I figure the pickup wont outlast even new steel galvanized fuel lines,so why waste the cash on stainless tubing...if it were in minty shape and worth it I'd do it though..

On my '77 GMC I got tired of replacing rotted fuel lines and I saw 3/8" copper tubing at Lowes one day for 10 bucks a roll ,ten feet long..so I bought that and replumbed it all the way from the sending unit to the fuel pump...ten years later when I finally scrapped that truck,the copper was green on the outside,but wipe it with a rag and it looked fine under the "patina"...I cut up city busses at the junkyard from the 40's that had copper tubing for air brake and water lines that still looked like new too...

 

[diesel4me]

Well,i cut that hose back and reconnected it,and the truck has started the past 2 days without using any starting fluid..but it was 77 degress out the past 2 days too!..it'll be dropping to the 40's and maybe 30's overnight,so if it'll start whwen its that cold,I'll assume that weepy hose might have been the cause..the fact it has year old fuel might have something to do with it too of course....

 

[tRustyK5]

Hopefully you got it Bob.

Rene

 

[diesel4me]

Nope!...soon as the temp dropped below 50,back to square one.....

I'm wishing I had a gas engine in this thing now...

 

[cegusman]

If that is the case. then it is a glow plug issue. I am betting only a few are working, when it is warm outside they are just enough to get it started.