Couple Questions on a 6.5 TD

[4xjunkie]

My dad has a 93 6.5 TD mechanical, in a K3500.

First question what should the boost be, roughly.

Second a little more techincal. When he starts the truck cold it smokes alot, white smoke, heavy diesel smell. When it really acts up, the motor is shaking all over the place. Now right in 75-80 degree weather it is real short, maybe 30 seconds and not real bad.

But when it gets colder out, around 50 degree, it will fill a parking lot full of smoke. And last 60-90 seconds and then clear up for the most part if you rev the motor it will smoke a little, until it is warmed up, after that it seem fine.

I check Glow plugs seem fine. I used a IR temp guns to try a isolate a cylinder, but is warm out and didn't last very long, all cylinders seemed to be about the same, left bank was about 30 degress cooler, but that might be the manifolds.

Not looking for the silver bullet, just need to know how to verify what is wrong. I was going to do relative compression check, but have not had a chance yet.

Thanks for any insight on this problem.

[Robyn]

Howdy

The condition you describe is quite common on high mile 6.2/6.5 engines.

If the compression is a problem you will see larger than normal amounts of blowby when the oil filler cap is removed with the engine idleing.
A small amount of whitish vapor is normal.

At this time I am not really worried about compression.

Check out the following.

Be sure to pull the glow plugs and actually test them using the battery.
The plug should glow bright red all the way to the tip.
Remember, no more than about 10 seconds on the power or you could damage the plugs.

If the plug/plugs only glow in the center they need replacing.

Now if the plugs are good the most probable cause for the excess smoke is that the injectors are tired.

As the injectors get time on them the nozzles wear and the pop pressure drops off due to several factors.
Instead of a nice fine spray mist at around 1800 Pounds or so they will start squirting a slobery pee stream of fuel and produce the huge cloud of smoke.

If the truck has a fair amount of miles on the clock I would recommend pulling all the injectors out and having them rebuilt or just replacing them with a fresh set.

There are many local places that rebuild these.
I see you are in Washington, close to Seattle or closer to the Oregon border ??

Diesel Fuel Injection Service in Portland does a right fine job and at a fair price too.

With a good fresh set of injectors you should see quick clean starts with little to no smoke on startup and better fuel mileage and more power too.


Best of luck

Robyn

[ronniejoe]

The condition you describe sounds like a glow plug problem. You have some dead cylinders at initial start up and it is taking a while to build enough heat to get them to fire. Fix the glow plug problem before doing anything else.

[4xjunkie]

Howdy

There are many local places that rebuild these.
I see you are in Washington, close to Seattle or closer to the Oregon border ??



I am closer to Seattle, just under the cadanian border.

[4xjunkie]

The condition you describe sounds like a glow plug problem. You have some dead cylinders at initial start up and it is taking a while to build enough heat to get them to fire. Fix the glow plug problem before doing anything else.

Well that is what I thought at first, but so far, checking out OK. I am going to look into it some more this weekend.

[DmaxMaverick]

If the glow plugs have been replaced recently, you could have "less hot" plugs installed. The controller/timer is preset and fixed, so a "standard" glow time may be too short. The controller in that truck can be modified (easy and cheap) to accommodate this. Another possibility is a failing controller. You may have issues with the injectors (probably should be replaced in any case, depending on the miles), but you need to eliminate the glow plug system before anything else. Another possible contributing factor is the IP timing. The age/miles of the truck indicate the timing may need to be compensated for chain stretch. All of the above results in hard(er) starts.

[4xjunkie]

You may have issues with the injectors (probably should be replaced in any case, depending on the miles),

I don't recall off hand, but I think it has about 130-145K for miles.

[DmaxMaverick]

I don't recall off hand, but I think it has about 130-145K for miles.

100-150K is the gray area. Other than that, much depends on how the vehicle has been used, fuel system maintenance and fuel quality over the years. They may or may not be "bad", but are nearing or due a replacement. But, like we said, verify a healthy glow plug system before anything else.

[opto]

I had exactly the same thing

Since I had a geardrive, IP, injectors and glowplugs laying around waiting. I installed them all at the same time, huge difference

But since my timing chain was relly worn and I mean really, I blame it quite a lot for this condition, however I never tried setting the timing before I made the swap

bad chain movie clip (http://www.hagberga.com/images/chain.avi) rather large file, sorry I didn't bother to resize it

[6.5 Detroit Diesel]

Injectors not to long ago, glow plugs within the last two months, truck still blows like a train when I first start it up. Rings maybe? Kinda looks bad when the trucks starts and for the next 30 seconds, it looks like a forest fire in our driveway.:D

[rhsub]

Have you checked the Housing Pressure Cold Advance (HPCA) system
The purpose of HPCA is to cut down on excessive white smoke at cold start up by advancing timing 4'
To check system;
Green wire on pass side of inj pump should have power when engine is below 80' F, this wire also powers fast idle solenoid, the control switch is at the rear of right cylinder head
If power is present check HPCA solenoid in inj pump by appling 12 V to terminal when engine is warm, there should be a very noticable increase in diesel knock
If no increase, check system by first removing fitting were fuel return line attaches to pump, this fitting is the housing pressure regulator. you should see a pin sticking out of the hole in the pump, this pin should push out of the pump when you apply 12v to solenoid with enough force to push the ball in the fitting off its seat, check to see if the ball moves, it is under spring pressure
Solenoid can be replaced without removing inj pump
Hope this helps
I tried sending this last night but the internet died on me so I hope it goes tonight :D
Ron

[4xjunkie]

Thanks. That will give me something else to look at, this weekend.

I plan on looking at it on Sunday.

[Robyn]

Even with the best hot shot glow plugs, if the injectors are peeing a slobery stream these things will puke out a horrible column of smoke, shudder and shake and all sorts of things until they get some heat in them.

If the glow plugs are OK, do the check on the case advance to be sure its working.

At this point I would not even hesitate to yank the squirts and get them checked.

Once the POP pressure drops and they start to get sloppy the startup characteristics go right into the toilet.

My 94 Burb has fresh injectors after the rebuild and I used the original glow plugs that came with the truck. Some heat red all the way and some are so so but the truck starts off quick and clean even in cold weather.

The injectors were popping at around 1400 give or take and the spray was more of a dribbling pee stream.

Paying to have the injectors tested is not really cost effective and I would suggest a fresh set. At todays cost of fuel you will save some $$$ with the better mileage that will result from a fresh set of squirts.


Best

Robyn