Engine/Transmission (1994 - 1998) Just got back from getting timing set and......

[Fordiesel69]

I had the local dodge dealer do the timing on my 12v. The mechanic seemed like he knew his stuff. He owned 12v trucks and spoke on par with what I read on here.



2 problems I had before that I thought would have gone away with the timing set to 15 degrees.



1. ) Stumble and smoke if trying to accelerate when cold. Both heater grids working.

2. ) After complete warm up (brand new genuine mopar tstat) I can slowly accelarate in park and when engine reaches about 2500 it will start to smoke a blueish white and you can hear a faint stumble. With an engine load, absolutly no smoke of any kind that I can see anyway.



Also I noticed the combustion noise did not increase much if at all. He told me it was 12 degrees and he set to 15 and now I would think I would be able to clearly hear the difference to some extent. What should I do next, ask them to recheck or check somthing else.

 

[RStankevitz]

Well when we had my dads 95 done there wasn't really any noticeable difference in sound. a slight power increase maybe? hard to tell.

Also no smoke either but i assume this is because they didn't give it any more fuel just a little more timing.

When they did my 96 they also installed a fuel plate and slid the afc housing forward. I had a significant power gain and also gained a little blackish smoke under load and acceleration. Oo.

 

[Fordiesel69]

Bottom line, should I look at maybe the timing was not done right, or should I put my new injectors in first?

 

[Vaughn MacKenzie]

I don't remember if I've mentioned this in any of your previous threads but have you gone over the fuel system and serviced your prefilter, or made sure your fuel heater isn't leaking? Sounds like you could be sucking air somewhere. That's a bummer the timing change didn't help it, but at least you ruled that out. It could be a faulty injector but it would have to be in pretty bad shape to cause those symptoms.

 

[Forrest Nearing]

so what's the problem? 15* isn't really going to sound much different than 12*

 

[Vaughn MacKenzie]

Going from 12 to 15. 75 on my '98 didn't change the sound noticeably, I think about 17 & up is where the pitch becomes sharper. By 21-22 starts sounding like a 24-valve.

 

[TurboFan]

What are the negative effects of advancing the timing? Where do they start getting risky for damage?



Hard starting?

bad with higher boost?

bad at low RPM?



Thanks,



Greg

 

[Fordiesel69]

I don't remember if I've mentioned this in any of your previous threads but have you gone over the fuel system and serviced your prefilter, or made sure your fuel heater isn't leaking? Sounds like you could be sucking air somewhere. That's a bummer the timing change didn't help it, but at least you ruled that out. It could be a faulty injector but it would have to be in pretty bad shape to cause those symptoms.

I have only looked for leaks. My question is, wouldn't there be some kind of surging, or stalling if there was air?

 

[GOlsen]

What are the negative effects of advancing the timing? Where do they start getting risky for damage?

Hard starting?
bad with higher boost?
bad at low RPM?

Thanks,

Greg

PDR Diesel Inc. The turbo diesel performance specialists! - FAQ

That'll get you started.

As far as the stumble, I developed a stumble at about 2k rpm, turned out the injector was leaking out around the base. I pulled them out, cleaned the bores, put some new washers in there, and the problem was solved. While the truck is running, if you look around the base of the injectors, if the washers are blowing by, you would see bubbles. I didn't have to put anything on mine, but you may have to use a soap/water solution to see them.

 

[JFaughn]

I have been in the repair bis for a lot of yrs , so I'm asking because I've seen a lot .
Did you tell the tech about your stumble .
I can't tell you how many times a customer would come in saying they needed this or that [ tune up ] , I put in all the tune up part [ by looking they needed replacing ] , then the customer comes back ****** off saying I did not fix the car , this is when he tells me about the problem .
In other words , tell the tech you trust what your issues are , diagnostics are the techs job , not the customers .
I say this because you did not in your post , I see no gauges in sig .
There can be many issues with any of these trucks , then you get older & miles .
3 lbs of pressure in tank to look for leaks in fuel system from tank to LP , fuel heat ***. , lines , hoses , then fuel pressure test , how old / long ago since maintenance has been done , fuel filter , valve adjustment ect , when chasing down a performance issue , always make sure the basics are covered .

 

[Fordiesel69]

I just wanted the timing done as it was on my list of mods and for the few symptoms. I have a set of 215's to put in and a set of 181 DV's coming, so I did not want to have them charge me to diagnose when it (could) be injector related. When he asked me why I needed my timing set, I told him the symptoms and he said it would take care of it. I am not blaming him at all for the fact it did not fix the symptoms, I just think there are 2 possibilties, either he did not set the timing correctly, or I have another problem somewhere else.



I have only taken a mag lite and did a good visual inspection of the fuel lines, and fittings. I did not pressure test it yet. Fuel filter is not new but was changed recently by the PO. The valves were all off on the exhaust and were only like 0. 25 ~ 0. 32, I set them to a 0. 20. Intakes were . 010 to 0. 11 so I did not bother with them.

 

[Vaughn MacKenzie]

Hopefully the tech did the timing adjustment properly in that he rechecked it once doing the final torque on the nut. It can shift or squirt back when attempting to tighten the pump nut.

Sucking air doesn't generally cause bucking or hesitation, but smoke & stumble like yours.

Vaughn

 

[Fordiesel69]

Ok, so i can just stick an air hose down the filler neck, then wrap a rag aroun the hose and apply lets say 5 psi that way the little bleed out by the rag should leave about 3psi in the tank. Then check for leaks right?



How do I tell if the heater is leaking, will it be greasy or will there literally be fuel coming out?

 

[Flinty]

I don't think the rag trick will seal effectively. This is what I built to pressurize the fuel system and it revealed a very slight leak at the fuel heater. I'm talking like one drip every 15-45 seconds. Seems insignificant bit it kept the truck from even starting. I built this out of a gas cap that I tore the top off of and I just threaded a 1/4" piece of pipe into it. No tapping or epoxy, I just screwed it in. The gage is from home depot found in the plumbing department for pressure testing natural and lp gas lines. I then filled the tank to 4-5 psi, this will take a surprising amount of air if the tank is not full, so don't be alarmed.

 

[BigPapa]

I haven't had a fuel heater on mine for the past 3 years and I haven't had any trouble even with morning temps down to 5*. Just take it out unless your in colder temps all the time. Lots easier than all the testing.



Scott

 

[JFaughn]

Any pressure should make a leak on the heater ,and every thing back to tank , thats whats up with pressurizing the tank , from tank to lift pump is a vacuum [ normal running ] so no fuel coming out , air going in .

 

[Fordiesel69]

I will rig up something to test it. Hopfully this will reveal a leak somewhere. The funny thing is, it will start without giving it any pedal now, so it looks like the timing did somthing.

 

[JFaughn]

I haven't see where you have done a fuel pressure test yet ?

 

[Vaughn MacKenzie]

FordDiesel look for the fuel heater to be leaking from the electrical connector. . . might unplug it and check there when doing your test.