hvanflee

I went to get the emission test done today, the guy running the test said it sounded like the engine is missing. I have been told this twice in the last 4 weeks. I must have forgotten what a smooth engine sounds like.

Anyway, my question is what will make the engine miss; bad injector, timing, valve adjustment, injector pump? Where should I look first? Is there any tests I can do to narrow it down?

Thanks

dodgedude361

emission test on a DIESEL? ??? :- we dont have those here

phox_mulder

[quote author=hvanflee link=board=13;threadid=20155;start=0#msg189340 date=1064528120]
I went to get the emission test done today, the guy running the test said it sounded like the engine is missing. I have been told this twice in the last 4 weeks. I must have forgotten what a smooth engine sounds like.

Anyway, my question is what will make the engine miss; bad injector, timing, valve adjustment, injector pump? Where should I look first? Is there any tests I can do to narrow it down?

Thanks

[/quote]

We're lucky enough in Utah to be close enough to Commiefornia that they are bleeding over.
We get emissions tests.

First thing I would think of is an injector sticking, but I'm not an expert.


phox

Gary Scales

A missing diesel engine????

How could the guy tell from the way it sounded???

Was it missing a clatter??? clat a clat a pffft

I live in a city where they are trying to mandate an emissions tests for diesels but as of this date, they have not implemented. Since you live up in the high country of Utah I wonder why it is an issue. Down here we have the 2nd smoggiest place in the U.S. (next to LA Ca.).

I would be wary of this inspectors comments since diesel emissions testing is in its infancy............ ;D ???

hvanflee

Yes, the great state of Utah needs more money, so every year they have us come in. For 15 bucks they put us on the dyno and check the emissions at idle and WOT. This has been a great way to track the health of our trucks. The max limit is 30%, my truck came in at .5% at idle and 13% at WOT (50 mph with load) my boost was at 18 PSI and my pre-turbo temp was at 900 Deg. HP was 136.

Holycack

I cant beleive you never noticed your moter was missing, I mean how did you get truck to the enviro cops if someone took your engine?

hvanflee

The guy running the emissions test, listens to these trucks all day and it was the first thing he said when he got into the truck. Also about 4 weeks ago. I had a friend in my truck that has worked on diesels most of his life. The first thing he said was the same thing, your engine is misfiring (is that a better word for it) ;D. I have a hard time hearing it, but I better take what they said to hart.

MnTom

The easiest way to find out whick one is missing is to start the engine (like first thing in the morning) when everything is cool and touch the exhaust manifold where it exits the head. If one cylinder is not firing the manifold will not heat up like the rest. If you find one that is cold try cracking the fuel line to the injector. BE VERY CAREFUL!!! See if you are getting fuel to the injector. If you are chances are you have an injector issue. If you don't get fuel then I would suspect a delivery valve issue. If it turns out to be a delivery valve or pump problem I suggest that you have Cummins diagnose it. Tell us what you find.
Tom

slighfoxs3500

I am a rookie but I know alittle of what to look for. The injector pop test is simple but you need the right tester and cummins or a diesel shop should have them. If its a delivery valve, you'll know when you crack the line. As mentioned by MNtom be careful, Lots of pressure required to get past the injectors and the injection pump has no feelings for you. If it is a cylinder problem, you can have your oil check for fuel dilution or carbon buildup. Blow by goes to to sump and should show up on an oil analysis. Monitoring the dipstick can aslo show you if raw fuel is getting past the rings. You can smell it and it tends to thin the oil. Some unburnt fuel may also be smelt at the tail pipe. Question, has your smoke changed color at all and your sump temps. If you have blow by, the sump temp level and pressure may go up. The computers and timing slips are my only other suggestions. Good Luck to yuh!

Cartman

lol..I had a friend once ask me something.. "what happens when a diesel detonates?"

I calmly told him.....It means its running!

Redleg

Try bleeding your injectors, your fuel lines might be getting air and are ready for a change. Replace the rubber connectors, and look for wetness on the steel lines.

98rammer

when cracking the injectors, look for two things....bubbles- which will tell that some/all the fuel isn't being injected (bad injector) and engine harmonics. obviously, if an injector is dead and you crack the line, the engine will not change pitch.

Tom

hvanflee

First, thanks for all the good feed back, jokes and ribbings.

This is what I did this morning. I started the engine and felt the exhaust ports. They all warmed except for #6 it stayed cool to the touch the hole time. Some ports warmed up faster than other #3 got to hot to touch fastest. One more thing, after I tightened up the #6 injector I noticed bubbles in the pool of fuel around the base of the injector ( I assume leakage from the piston)

I then cracked the #6 injector open and fuel came squirting out.

So, can I assume I need to focus on the injectors? If all the exhaust ports got hot at different rates do you think I have more than one injector with a problem? Should I replace them all?

Can injectors be rebuilt, or do I need to replace the one or ones that are bad with new or used ones?


Please tell me about injectors. Are the stock injectors crap? If money IS an issue should I find a set of used injectors and give that a try? If money IS NOT an issue what would you buy? (Remember I have already blown up one engine and I am not ready to bomb the new one to the max)

Do I need to take my problem to a shop or can I do the work myself? I need my truck for the Elk hunt, this week end and most of my spare time is spent making and delivering Cool-Down Timers.

Thanks,
Howard

Redleg

Has the problem returned? Generally air gets in (your bubbles) from bad lines, running empty, maybe bad lift pump. If the problem returns, I'd start with the fuel lines.

hvanflee

OK, sorry I left off that information. After bleeding the #6 line, the exhaust outlet still did not get hot. So I don't think air in the line is the problem. Bubbles came from around the base of the injector, I am thinking the air/bubbles are coming from the piston pressure and not from air in the lines.