93 6.5 unknown injectors

[searstractorfan]

My 93 6.5 has had the heads changed on it..I was told they are 6.2 heads, no problem i dont think...BUT my exhaust manifold on the turbo side has had holes cut and then capps welded in them so the injectors can stick into them....So it seems to me that the injectors are to long....So did they use the 6.2 injectors in my truck? can that be the reason why I have not a great show of black when I stomp the throttle? Im currently running it N/A because the waste gate is frozen and i got it open(soon to be fixed i hope).....all I get is a very good haze, id think with the IP cranked up all the way id get coal black like my cummins.... any thoughts?

 

[buddy]

no smoke means you have plenty of air. So you must have stuck the wastegate closed and getting lots of boost. You have a boost gauge?

 

[bk95td]

The older 84-90?6.2 heads have the injectors at a different angle. It shouldn't be a problem as long as the short body turbo injectors are used. If the po had to mod the exhaust manifold then chances are that your engine has 6.2 long body injectors in it. You may even have the 82-83 coarse thread injectors. There is no short body replacements for those. I can get pics of the different lengths and threads if you'd like.

 

[searstractorfan]

Im not pulling mine out to find out what they are, I can prolly take a pic of them, dont know how well it would turn out...YES i have aboost gauge...0 boost unless you tromp the go pedal in 1st gear and run it to the red line then u struggle to make 1psi!!! Im hoping i can swap these bad boys out for some true 6.5 HO injectors later down the road...I dont wanna swap the head just to be able to do this...man that would be my luck....

 

[bk95td]

IF your gauge is correct ,you have turbo problems,not injectors. I'll get pics of the different lengths and threads.

 

[bk95td]

Injector pics

Got pics of the 3 different injectors used in 6.2-6.5 engines.
The 6.5 turbo injectors are shorter in the area between the threads and the nut used to tighten into the head.
The 6.2 n/a injectors are longer in the area between the threads and the nut to tighten. In that area there is a taper and then straight area before the threads.
The 6.2 long body coarse thread is the same length as the fine thread. The area between the nut and threads is all tapered.
I can get lengths if you need them. Pretty easy to see the differences.

 

[great white]

If I understand what bk95td has posted here correctly, you're screwed for swapping in marine injectors (HO) or later style turbo injectors if you have the coarse thread 6.2's.

I would also think the 6.2 NA injectors are a lower pressure pop than the 6.5 TD injectors.

You could always have them rebuilt to higher pressures I suppose...maybe even with the marine nozzles...but I'm just guessing here.

 

[searstractorfan]

bk95td i know I have a turbo issue..The waste gate is frozen in the open position......Im saving to buy an ATT turbo to fix that problem.... As for the injectors, Im gonna say by looks of your pics ive got one of the long bodied 6.2 injectors.....man I hope their the fine thread ones.......Do the 6.2 injectors spray as much as a 6.5? My IP is cranked ALL the way up and I dont get nearly the smoke that most 6.5 guys can get....ive got decent(NOT GREAT) power when the turbo was working..MY 94 will smoke pretty good and its stock(well IP isnt turned up any, yes its been changed to mechanical)

 

[6.2 turbo]

I had 6.2 injectors,and they reduced power,but not smoke,your pump must be shot or it has the wrong plunger spring inside.

 

[Pruittx2]

6.2 and 6.5 injectors are for the most part the same,, except the pop pressure,, but the nozzles I think, are the same.

 

[bk95td]

On the injector application sheet I have it says: 82 6.2 [which would be coarse thread] uses OSD248 tip,
6.2 long body uses: OSD253
6.5 n/a and turbo use:OSD304
6.5turbo marine usesOSD311
It may be possible to use the bigger 6.5 nozzles in the coarse body injectors.Not shure.
If they are the 6.2 coarse thread injectors in there now it could be limiting the amount of fuel delivered.
As far as your smoke thing,smoke is wasted fuel and causes very high exhaust temps. Any more than a puff untill the turbo catches up is a bad thing.

 

[buddy]

I dont know hot a turbo wastegate on these sticks open, they just operate on a lever, and they swing with a 1:1 ratio of displacement. If its stuck its just because the actuator on the outside itself is stuck. And if you had no boost the truck would be incredibly slow and weak and you would have tons of black smoke.

 

[searstractorfan]

I dont know what caused it to stick either but I had to force it open....It was stuck almost seated completely shut and I locked vice grips onto the shaft and drove the truck around in 1st gear at like 2700rpms to get EGT up to like 600degrees and then would stop and hit the vice grips with a hammer to open the waste gate...once it got into the open position i havent messed with it...i was getting WAY to much boost and once boost went past 10psi myt EGT's and block temp went through the roof....now ive got a 190 thermostat and my wastegate open and block temps stay almost perfect 190 all the time... I know black smoke is wasted power and fuel....I understand the hole less smoke is more power, my 5.9 cummins operates well with that moto!!! Ive basically kept this truck as my "play"truck..I use it when I need it and play with it alot...I always thought it lacked the smoke when I was playing with it...and always wondered why..when the turbo wastegate was in the almost shut position black smoke was gone by 5psi and at 10psi she was running smooth at 14psi+(ive seen 20 when tires spinning and engine revs easily) she rolls gray smoke.....

 

[buddy]

Maybe your lift pump is dead then, so you are starving for fuel. Only way you wouldnt be blowin lots of smoke with a completely open wastegate. that or the IP is not working correctly, maybe you turned it down instead of up?

Need to do lift pump/OPS diagnostics.

 

[WarWagon]

Buddy has a good suggestion to look at. My lift pump tested fine at idle with 7 PSI but the boost fell off at higher RPM. I had to turn the boost spring down after replacing it.

I turned up a 6.5 DB2 pump 2/3 of a turn. Smoked until I turned the turbo up. (New lift pump and clean stocking in tank.)

1/2 turn on a NA 6.2 pump and I could not get the smoke to go away @ 14psi boost. Had an exhaust leak pre turbo that did not help. Painted the fender black in 450 miles towing...

What direction did you rotate the waste gate to open? You pulled the rod out of the can to open it correct? 93 factory boost setting is ~6 PSI max with the can spring.

Next look at the throttle cable. Had someone floor it engine off. Then reach under the hood and see if you can open the throttle further by rotating the lever on the pump or pulling on the cable.

 

[searstractorfan]

I just put a new lift pump about 1200 miles ago..It was a new one for a 94 and up truck(it runs more PSI than the 93 and older pump).... I can get a pressure gauge and see what the pressure is(I can hook into the WIF drain right?) When I rotated the wastegate I pushed it toward the fire wall...I DONT have the wastegate can system on it! if it were to break lose and decide to move(THAT aint gonna happen) it would just float freely.... so theirs NO chance of boost happening unless you make enough RPMS to create enough exhaust to spool the turbo a little(which 1st gear on the rev limiter will get 1psi)....When I installed the new lift pump, you could feel the pump running, and you had fuel at the WIF valve and at the bleeder on the fuel filter....Im wondering if I need the Feed the Beast fuel fittings that im starving my IP for fuel....I didnt turn the pump up, the previous owner had a friend do it(Im friends with the friend and hes a diesel mechanic and says its maxed...) so I cant be 100% sure its turned correctly.... other than it cracked the original heads about 3 months after doing this(they didnt have gauges on it!!!)

 

[bk95td]

The 92-93 lift pumps are higher psi than the 94+ ones.

 

[searstractorfan]

hmmm, the orielys computer said that the 94 and up pump was....... it was supposedly good for like 7-9psi steady pressre and the stock 93 and down was good for like 5-7psi.... im thinking of going aftermarket regular fuel pump that pumps like 10psi and trying that...

 

[buddy]

I think that in like 98 they supposedly upped the pressure on the LP, but it was reduced from the mechanical to the electronic IPs originally. I do not know why. I guess it worked too well at the higher pressure that GM had to take things down a notch.

And they fail regularly, and there are other restrictions to cause your problems if you put a gauge on it and notice that there is no fuel pressure at idle or if it goes to vacuum under load.

Like do you know if the OPS is working? Check the fuel pressure at idle, then try to extend gauge to the windshield or into cab and see what it is close to WOT.

Remember that is prefilter too, at the water drain, so if the filter is clogged would be a problem. You can pull the filter and pull out this dumb corkscrew thing that goes into the cental FFM fuel input shaft so fuel is restricted around the heater.

Snotty tank sock will prevent fuel from getting to IP as well.

 

[searstractorfan]

Tank is clean..had that out to replace some cheap ruber hose someone put on as a fuel line(she was sucking air)..and then had to open it up to retreive a lost socket(That was an oops)...That sucks, didnt know all that about the LP's....I went by what Oreilys told me...Im thinkin maybe high PSI pump on a later update....Ill have to get a fuel pressure gauge and read the pressure...I just feel this thing should smoke like a freight train....Thanks for all the help!!!