Unburnt Fuel smell, Coolant loss, Fuel mileage loss, HELP

[Rick Henderson]

About 6 months after I had the injectors replaced, smoke and unburnt fuel smell happened. I am not sure how long after that the coolant level began to drop and once had hydro lock. I unscrewed the coolant cap until this issue and be resolved. Meanwhile, I am still driving the truck (2003) with 265,000 miles.

I am not working right now and would like to resolve this myself. Only the Edge is installed, but on my shelf is the Diablo Predator, and the Hypertec unit.

I have never raced the truck. Also installed is a larger exhaust system to help remove the hot gasses.

The injectors were installed out of the states and by a diesel performance shop. He had problems with one of them and said he used some expensive sealant to repair it. After reading the posts from Duraswede, I wonder if the tech didn't use the removal tool and installer tool and cracked the sleeve?

Would that have anything to do with my unburnt fuel smell?

Thanks for your help.

[Rick Henderson]

It looks like after reading some other posts that I will remove the glow plugs on the suspect cyclinder first and check for moisture/coolant.

If the injector sleeve is leaking i.e. bad seal, o-ring pinch, etc., would that still cause my tailpipe to smoke and smell like diesel? It passed emissions a week ago with a 18 and 40 being the limit.

I will also screw the coolant cap back on and put a empty bottle at the end of the coolant overflow tank to see if it is pumping it out and I didn't see it.

Any other suggestions?

[Kennedy]

The presence of coolant in the cylinder can make for funny smells as well as affect combustion. Not sure what the previous mechanic had problems with, but I woukld start my investigation there.

[Rick Henderson]

I took my Diablo Sport Predator and checked the Data 2 and discovered that 6 and 8 are showing .1 or .2ms pwm and the others are around .3-.4-.5. It also shows number 1 -2.10
2 1.04
3 .26
4 1.66
5 - .15
6 -4.17
7 .82
8 -4.05

So it looks like I am having problems with the injectors on 6 and 8 for sure. Can someone help decipher this? Thanks

[Rick Henderson]

I don't smell any antifreeze in the exhaust, but smell a lot of unburnt fuel.

[Duramaster]

Since your Predator is capable of showing the closure time of the injectors, does it also show the injector BALANCE rates. I would be more concerned about the balance rates. I had one truck in particular that would BURN through a set of injectors about every 30k miles. He was a hot shot hauler and I think he also ran his truck a little heavy at times. He also used BRAND X fuel filters all the time.

[Rick Henderson]

The predator does not show injector balance rates. I also called the manufacturer and asked if they had another model or an upgrade and no to both.

From what I have posted on the numbers, does it look like specific injectors are bad, or do I need to be sure and get the injector balance test?

Thanks,
Rick

[Kennedy]

The Predator does read injector balance but doesn't do it very well. At least not compared to a Tech 2. It seems the Pred balance rates come up high as does most other 3rd party scan tools. It must be something in the averaging/math or refresh rate.

The list of numbers that you put up is the balance rates. I'd check again with a Tech 2 on a warm engine and see what you get.

[Rick Henderson]

I thought that is what I posted up above, but this morning the predator manufacturing company employee said that it doesn't show the injector rates, I don't know.

Anyway, I brought it in this morning to a local diesel repair center and they clearly show that cyclinder 6 and 8 are way off compared to the rest. They spent almost 2 hours diagnosing it. Now do I just replace those two? I will be doing all of the R & R myself.

Thanks

[Duraswede]

I thought that is what I posted up above, but this morning the predator manufacturing company employee said that it doesn't show the injector rates, I don't know.

Anyway, I brought it in this morning to a local diesel repair center and they clearly show that cyclinder 6 and 8 are way off compared to the rest. They spent almost 2 hours diagnosing it. Now do I just replace those two? I will be doing all of the R & R myself.

Thanks

my predator shows both balance rates and PWM injector signal, i dont remember if both was under the engine data 2 or maby the balance rates was under "fuel data"

you had the luck to have the trouble cylinders on the same side at least, but the left side (with the even numbers) is the worst side, there's a lot of stuff that must be removed and there's not much room to work on.
so don't try to save some money just buying 2 injectors, replace all 4, you will tear your hair off if the others fail a month after reassembling it..

[Kennedy]

With the history of the LB7 injectors I'd have to have a pretty good reason not to do all 8 as a set.

[Duramaster]

Hey Rick............... What year is your truck? I forgot and did not see it posted. I borrowed my friends MODIS (Snap-On Scanner). I am trying to see if it lists Injector balance rates. I do not own my own GM Tech 2. My cost on one is around $2500! Ouch!! I am not allowed to take them home unless I am driving a customers vehicle home for whatever reason. I agree with Kennedy, the major issue with the LB7 (any year) is the injectors. I have not checked prices for injectors in the aftermarket scene but I believe that injectors from GM are about $250 each plus cores. Don't quote me on that. I could be way off base on these prices. What are your plans with the truck? :confused:

[Rick Henderson]

Jason,

I really hate to buy a new set of injectors but, it looks like I will have to. I have a good family friend that is a diesel mechanic, but works on Fords all day. He said that I should get the injectors and we could put them in on a weekend.

It seems just like yesterday that they were replaced. I spent at least two hours reading the posts of members that have had to replace them. Doesn't seem right. Oh, my truck is a 2003. Looks like I will start looking for the injector puller and the sleeve install tools.

[Duraswede]

Jason,

I really hate to buy a new set of injectors but, it looks like I will have to. I have a good family friend that is a diesel mechanic, but works on Fords all day. He said that I should get the injectors and we could put them in on a weekend.

It seems just like yesterday that they were replaced. I spent at least two hours reading the posts of members that have had to replace them. Doesn't seem right. Oh, my truck is a 2003. Looks like I will start looking for the injector puller and the sleeve install tools.
the injector puller is not nescesary, just grab the injectors and pull them out while twisting them.

in my opinion, the worst job is to remove all the crap that is mounted over the engine, that took me at least 10 hours.
i removed as much as possible to make enough room to work on.
so, if you can afford it, the best would be to replace all eight, i got a real smooth running engine that sounds like a gasser now, i can hear that my belt tensioner has a bad bearing, with the old injectors it was impossible due to the heavy knocking.
i searched on google and found very cheap injectors, for $149, plus 75 in core charge, they had even bosch reman injectors for something around $300
if you replace all eight, consider to add extra filtration to your fuel system, i mounted a kennedy mega filter kit because i dont want to change injectors any more as long as i own the truck.
even though we have good quality diesel here, i want to be on the safe side.

[Kennedy]

A set of new/reman injectors (genuine Bosch/GM) will run about $2,000 exchange. When you go to pull them, you'll get a ton of grit in the inlet bowl from the rust and crap that gets ground between the line nut and the line. Be sure to clean the lines very well or replace them and try some dielectric grease to prevent further corrosion.

This rust and crap is responsible for many poor performing trucks. It seems no matter whet you do to keep things clean and suck out the debris, it still gets inside. For this reason if no other, I'd say do a full set.

[Duramaster]

It's funny that you mention the lines Kennedy. The original lines are that greenish color and the replacement ones are nice bright stainless. I have installed lots of them and haven't seen any more corrosion issues. There was a time that GM wanted us to seal the top of the line nut with a form of silicone sealant. It did a great job because I had a few come back later that needed injectors AGAIN and there was no rust or corrosion present. Since then GM has said that the silicone is no longer needed. Go figure........... :rolleyes:

[Duraswede]

i had this rust problems too, it was very difficult to loosen the line nuts, i cleaned the rust inside the nuts and on the cone with a rotating wire brush, and after i reassembled it i dripped engine oil down between the pipes and nuts.
and dont forget to clean the injector lines internally!! i flushed the entire fuel system (except the Inj. pmp.) with self-drying carburator cleaner.

[Rick Henderson]

Should the cups be replaced also while I am at it, or just the ones that are leaking? Tonight I went to start it and its locked up with coolant. Looks like I will be taking the glow plugs out tomorrow. The tech apparently tightened the coolant cap.

[Kennedy]

For the line/nut issue I would think a good squirt of CRC spray dielectric grease would go a long way followed by some tube dielectric, and then if you wanted to you could try a sealer on top. A simple umbrella seal would be nice. The key is to allow an external path of escape should the line to injector interface ever leak.

Rick,

If you've got that much coolant in it, I'd say a crankcase flush and oil analysis tracking would be a very good idea. Dex Cool or any anti freeze can tear things up inside very quickly.

[Rick Henderson]

I have been reading for hours from those that have done the injection r & r, along with fixing the leaks associated with it. It looks like I will be installing a secondary filtration system and also continue to faithfully use the additives.

The first injector replacement was at 165,000 miles and now I am at 265,000. Here is the parts list that I had replaced before. I don't know if these are the correct numbers now as my invoice shows that they were purchased in March of 2006.

part number.............description.........QTY........ ................................
97228933................Gasket..................2. ........................................
97188720................Pipe...................... 2.........................................
97188721................Pipe...................... 2.........................................
97188722................Pipe...................... 2.........................................
97188723................Pipe...................... 2.........................................
97188896................Gasket..................2. ........................................
97228933................Gasket..................8. ........................................
97729095................Injector.................8 ........................................

If there are two injectors that are leaking coolant, I wonder what they are going to look like in the sleeves? Also, with the last set the tech said it didn't look like the pipes needed to be replaced, but he did it anyway. I can't remember if they were the stainless ones, or the green looking ones.

[Duramaster]

All you have to do is look at the engine at the left side (driver side) and see if the lines are bright stainless or yucky green color. If they are the stainless colored then the lines will probably be ok. Otherwise if the lines are corroded then the new ones will be around $80 each.

[Rick Henderson]

Last night and this morning I tore into it. I cannot get the fuel return line bolts off. I used a new 5mm allen wrench and from the looks of it, the previous tech rounded two or three of them. I am going to try and use a punch twist tool. Luckily they have them locally, but for $10.00 each.

Is there anyway to get out the injector sleeves without the tool?

[Duraswede]

Last night and this morning I tore into it. I cannot get the fuel return line bolts off. I used a new 5mm allen wrench and from the looks of it, the previous tech rounded two or three of them. I am going to try and use a punch twist tool. Luckily they have them locally, but for $10.00 each.

Is there anyway to get out the injector sleeves without the tool?

my bolts were quite loose.. maby the previous tech tightened them too hard.. dont forget to replace the sealing washers..
i have heard that you can make a sleeve puller from a injector, but it's better to buy a puller and send the old injectors back to get money for them.. i can sell my sleeve tool quite cheap if you dont find any other locally, but the shipping will be high so it's better if you find one near you, i dont know what they cost at the dealer but i found my on Ebay for $89

[Rick Henderson]

my bolts were quite loose.. Maybe the previous tech tightened them too hard.. don't forget to replace the sealing washers..
i have heard that you can make a sleeve puller from a injector, but it's better to buy a puller and send the old injectors back to get money for them.. i can sell my sleeve tool quite cheap if you don't find any other locally, but the shipping will be high so it's better if you find one near you, i don't know what they cost at the dealer but i found my on Ebay for $89

I borrowed one this afternoon from a local diesel shop. The same place that diagnosed the two failed injectors. Thanks for the offer. I have been looking on Ebay for the last three or 4 weeks and missed one a couple of weeks ago.

H & H has been very helpful. They even explained how to put on the o-rings. Jerry said they will tear if you don't straighten the up after installing them. He said to use a small pick (or something similar), install the o-ring over the pick and sleeve and moved the pick around the sleeve. He also suggested to use a little bit of oil on them to ease the installation. On the bottom of the sleeve to use the Loctite 272 or the high temp equivalent.

Speaking of that, I found that there is more than one RED Loctite. One is regular RED and the other (The correct one) is High Temp. Red. I didn't know there were more than one RED and almost made that mistake. I wonder if that is what the tech did the first time. He might of used the regular which only is good to something like 300 degrees. The High Temp. is good to like 450 degrees.

[Rick Henderson]

Here are pictures of 4, 6 and 8 injectors. Also the crap that was inside the inlet side of the injector on 4, 6 and 8 are the same. 5 is clean.

[Rick Henderson]

This one came out of number 4 cyclinder. It looks like this is one of the injector sleeves that was leaking the antifreeze. So 4 is wet, 6 and 8 are dry and carboned up. Any other comments?

[Duraswede]

i used volvo's strongest thread locker that was rated @380 degrees C (~650F) and i applied some grease on the O-rings before i mounted the sleeves.

on your sleeve it seems like there's carbon debris on the surface that should seal against the head, look on the marked area on the pic below.
if that is carbon, then you have a gap between the sleeve and the hole in the head, so inspect the heads for damage in that area.

[Rick Henderson]

i used volvo's strongest thread locker that was rated @380 degrees C (~650F) and i applied some grease on the O-rings before i mounted the sleeves.

on your sleeve it seems like there's carbon debris on the surface that should seal against the head, look on the marked area on the pic below.
if that is carbon, then you have a gap between the sleeve and the hole in the head, so inspect the heads for damage in that area.


Thanks,
I got a bore cleaning kit from the local gun supply shop and some of their non lubricating cleaner to remove the carbon. I will inspect what you mentioned and hope to heck its ok. Thanks