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What did you do with your GMT400 today...or yesterday....

For intitial start I would try to set it perpendicular to the engine. Last two times I’ve had to push the IP over to the passenger side to set timing and TDCO.
That I shall do before I try to start it.
Marty, That's a big turkey your taming there with a Snap-on and Craftsman ratchets!
Oh no, Snap On breaker handle in a 3/8ths drive, aaaand, dropped Forge Multi Wrench, sawed to pieces to make a reversable IP nut wrench.
@ak diesel driver is the one that give Me the idea to get a reversable ratcheting end wrench for building a wrench for the IP nuts.
The wrench aint quite right but it functions as it is and, I’m afraid to go to hacking on it and wind up with an even bigger mess. 😹😹😹
 
Welp, so phar today.
Lower shroud installed, then removed to trim off where the radiator drain cock is located. Make that a little easier to access.
Lower shroud reinstalled, fan attached to WP, upper shroud is on and the radiator is filled.
Cleaned the batteries, filled them with distilled water and now corrosion proof the posts and terminals, then, install the positive cable system.
Probably be about time to get the hands warshed, change out of these grubby blue jeans and get ready to go over to the catholic school for a feast of all feasts. 😹😹😹
Gobble gobble gobble
IMG_1266.jpeg
 
Went back and re-adjusted the light load advance cam on the throttle shaft after reading up on it last night. found out it's main function is to give a light amount of advance under low RPM and light loads. it's said that once the RPM is up the internal housing pressure takes over. it all kinda works together like the gassers with the vacuum advance and springs in the distributor. fired it up cold with the cold advance solenoid connected. it didn't sound like all 8 rods were trying to exit the chat like before. after warming up, I let it sit there running watching the engine and exhaust looking for how smooth it ran, dropping it into gear and only applying the brake just enough it held from rolling waiting for the engine to shake or move the truck. seems a lot smoother, prior to moving the IP, one thing I noticed was when sitting at a stop light with barley enough pressure on the brake pedal, the engine would have a random single shake that was enough to cause the truck to creep forward slightly then stop.

Probably not the right description (random single shake) but it's like a gasser with an occasional "half miss" caused by timing or a carb idle circuit not adjusted right. After retarding the IP slightly and going back and making the change to the advance cam it seems to run smoother and holds it's idle smooth. drove to my daughters house for the Thanksgiving celebration, all seems good but still throws light grey smoke unless I feed the onions then the grey turns to black smoke. My guess is the grey has to do with the blow by allowing some oil past the rings or valve seals.

before I left to my daughters house I noticed smoke coming from under the front of the truck and discovered the drain on the CKO provent must have came off on the road. the end of the hose was just there on the frame rail, it had painted the lower control arm and coil spring with oil too. ended up shoving a bolt in the drain hose for now. I would like to find a way for it to drain back into the block but not have to pull the pan or engine in the process.

all in all it seems to run better now, I will do another cold start test in the morning with the solenoid connected and see how it does.
 
To ID the oil is source of grey smoke- just drain all the oil and drive a couple thousand miles! Haha. Ok, maybe not. If you vent to atmosphere rather than pull back into the turbo- clean oil off the turbo and clean the intake manifold and plumbing best you can- then drive it a while like that with the oil slobbering on the hiway the smoke should clear up if it is from that.
The purpose of cleaning all the oil from inside intake and such is soon as you let it vent to atmosphere, the other oil if not cleaned will continue to feed the smoke and the testing will take a long time to determine if that was it.

Long term there are people who simply vent to atmosphere. I don’t suggest it because the epa and your local government won’t like you and might beat you with a wet noodle or something for killing the spotted tree whales. Also, you aren’t evaluating the crank case pressure as well as it should which causes more blowby and blows out seals which makes you use even more oil. And all your oil is being lost instead of used.
On a brand new engine it doesn’t make good economic sense to add a good provent system because it will be a few years before saving enough oil otherwise lost to pay for the filtering system. I justify it by knowing I am ahead of the game and hope to run in a slight vacuum to preserve the seals from day 1 and have considered using a vacuum pump to actually be in a slight vacuum for the power/mpg advantages (still jot economically justified).

In a tired engine it really depends how much oil you consume if it is economically justified. Visible smoke justifies it by ensuring you pass smog if required in your area, and stops people from turning you in to the po-po for a smoke show.

As to adding a return line to the engine for auto drain- I don’t see how without removing the pan. I am obviously pro-provent. But paranoid of the idea of returning it along with the turbo return location because I am overly paranoid about anything blocking the turbo return flow.
Really I am 99% convinced it should be safe. You have to have a lot of provent flow to mess with the turbo flow. But I am a “prove it” kinda guy and never wanna recommend someone becoming the guniea pig. But I could swear quadstar or someone makes a fitting for the two into there already. I really can’t imagine a scenario that the provent flows enough oil to impede the turbo flow- but my ofd red flags alert to a possibility so I have to mention possible sky falling along with the idea of returning there.

You HAVE TO HAVE the check valve in the drain line if not returning oil into the bottom of the pan sump thats has it submerged. DEFINITELY BUY THAT FROM PROVENT! A check valve of improper pressure will completely ruin an otherwise perfect system. Blocked valve obviously nothing drains. No valve and the system becomes pressurized equally on both sides and no oil will be separated or recovered.
A reminder of their system:
 
Yeah, this CKO provent doesn't have a check valve in it. I did try venting with a tube from the valve cover to under the truck but that turned into a smoke show! stopping at an intersection I had so much oil fog collecting up around the front of the truck a fella would thing something was on fire. the smoke was about like on a gasser you filled with oil and split half of the oil over the manifolds and ran it to burn it off!

I was thinking of attempting to add a threaded port on the turbo oil drain plat that mounts on the block where I could connect the hose from the provent drain, but the crankcase pressure thought stopped me. I figured the pressure would not allow the oil to drain back when running along with the oil that was coming from the turbo would possibly be pushed up into the provent. Could do the same thing if a fitting was put into the pan below the oil level. I can pull the hose that goes to the turbo boot and put my thumb over it while it's running, the pressure will build up enough to inflate a balloon easily within seconds, push oil up the dipstick and all!

Yep this engine is very tired and I'm sure the rings are beyond toast, maybe even the pistons too. It makes that 6.2 with cracked webs look to be in much better shape on that aspect.
 
Well after finding a bad battery in my 95 the other day, installing another spare I had, and charging them up. leaving it sit for two days I go out this evening to check on it only to find them dead once again! I must have an intermittent drain. when I checked for a parasitic drain the other day I couldn't find anything. my volt meter wouldn't read any draw, used a test light and it only had a slight glow to it. I have it on the charger again and thinking about trying to rig up a maintainer to keep it plugged in when parked.

I am suspecting the other "new" battery is also failing as I had pulled the bad one out (it's match) left it sit on the porch, checked it with my meter and it was totally dead from holding at 8 volts when I tried charging it. This sux! both are just a couple months out of replacement warranty. I guess I will be on the lookout for a pair of batteries off the marketplace or used. tired of new ones not lasting anymore.
 
IMG_6529.jpegIMG_6530.jpegTowed tractor on trailer from Stevensville, Montana to Layton, Utah, 523 miles. Truck engine performed well. Saw 16 psi boost momentarily while aproach the crest of a 6,000’ pass in Idaho. Coolant temp reached 195. I backed off the pedal to 13 psi and temp started to drop quickly. Otherwise average speed was 65 mph with a boost of 5 PSI and coolant temp of 187. Most importantly, no leaks.
 
View attachment 90987View attachment 90988Towed tractor on trailer from Stevensville, Montana to Layton, Utah, 523 miles. Truck engine performed well. Saw 16 psi boost momentarily while aproach the crest of a 6,000’ pass in Idaho. Coolant temp reached 195. I backed off the pedal to 13 psi and temp started to drop quickly. Otherwise average speed was 65 mph with a boost of 5 PSI and coolant temp of 187. Most importantly, no leaks.
I been waiting for such a post. @Big T


I have a tuned ECM for my truck. Going to do the initial injector line bleed and fire up with the OEM computer.
Get it fired and nicely warmed up, timing off set function, then, install the new ECM. It will also go through the timing function but nothing should have to be changed.
Oh yes, I did purchase one of those temperature foolers so that might make it a quicker operation.
 
Well battery #2 in the 95 went fubar. after charging last night with my small charger, check them today and they are dead. disconnected them from the truck and measured voltage. the spare I installed is at 11v and the new one from 21 is at 9v. I know the spare was decent as it was holding well to use on the 6.2 to crank it. I have no idea what would have caused both to have an internal short. Now I need to replace both on the 95 truck
 
Got the PS EVO valve reinstalled.
I will say. If a person plans on tackling the removal, or replacing of that valve,’on an IFS four wheel drive truck then:
Have on hand a semi deep 1-3/16ths socket, preferably in 3/8ths drive, but, a 1/2” to 3/8ths drive adapter might work.
All I have is a SO deep 1-3/16ths socket and there was not room between the engine mount and the back of the PS pump for it all to fit. There would be room for a semi deep socket and an adapter with a 3/8ths drive ratchet.
A shorter 3/8ths drive ratchet handle too because there is no room for a 1/2” drive ratchet or a longer 3/8ths drive ratchet.
Next thing is a cheap brand of a 1 3/16ths end wrench that can be cut off to use the box end in tight quarters.
The electrical connector end of the electro magnet has to be removed in order to gain access to the hex of the retaining portion of the valve before the electro control end of the valve can be uscrewed from the PS valve.
I was fortunate that I had installed an improper fitting EVO bypass kit and didnt have to deal with the snap rings on the back of the EVO.
There was not a semi deep 1-3/16ths socket, or, end wrench that I could cut off in town.
I however did find this Milwaukee adjustable crescent wrench
IMG_1280.jpeg
And would not have been able to get the EVO back in and tightened without this tool.
I forgot to measure but I think the handle is about 8” long.
I was able to use the Snap On 1-3/16ths socket to get the valve screwed partially in through the easy to turn portion of the install, just gripping it and turningthe socket attached to the retainer/bolt portion.
And so I did not reattach the wire connector portion of the EVO thats held on with a wonky C clip and a regular C clip. I had been running with the wires disconnected before the engine removal.
I think that there is not an EVO bypass kit made for the pressure hose on the hydro boost application of systems.
All kinds of them for the vacuum boost brake/PS units but not a thing for the PS pump of the 6.5 variety.
 
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Finished connecting the Air Dog LP system. Shortened the wires to the underhood fuse box and to the L side battery. Connected the battery voltage wire direct to the battery, it is a long ways around the back of the engine to the alternator and I already have several aux wires routed back there so decided to go to the left side battery terminal positive bolt lug, utilizing one of these.
IMG_1281.jpeg
After connecting the negative cables, opened the FFM air bleed valve, attached a hose to the nipple, into a translucent jug, turned on the ignition switch, FP gauge stayed on zero ? ? ? ?
Stepped around for an under hood visual, fuel squirting all over but into the jug.
Hurriedly turned off the key. Tightened the air bleed valve atop of the FFM and opened the water drain valve, ignition key back to run, FP holding on 10 PSI and fuel flowing into the jug.
Key back to off. Closed valve, removed jug.
Hooked remote start button to the battery + and other end to the PM starter solenoid terminal.
Key to run, notice very short GP cycle.
Using remote start button, crank engine, maybe 30 seconds, fuel emitting from a couple of the injector line nuts thats loose.
Give it a break for a couple of minutes then crank again. Fuel squirting from the rest of the line nuts on the RH side. Tightened those nuts.
Switch back to run and crank engine. Getting fuel from a couple of those injector line nuts, battery getting kind of low so hooked Charger to battery, on 10 amp mode and allow it to charge for about a half an hour.
Key back on, still short WTS cycle.
Crank engine, fuel from all four line nuts. Switch back to off, tighten the rest of the line nuts.
Turn on switch, short glow cycle, Crank engine, lots of smoke, no real fire.
Tomorrow set injector timing back so that IP is more parallel with top of engine, then check to make sure that the GP solenoid is getting battery voltage to the + terminal.
 
@dbrannon79
One shorted battery will often kill a good one connected to it.
You can try the one battery by itself to see if it will hold- if so a recon battery or one from a junkyard to match it becomes the gamble.

Otherwise get two new ones.
Of the other truck is down, steal those batteries.
Yep that was what i was thinking. both batteries are disconnected and plan to check them tomorrow again to see if one went down.

the 93 has batteries from the JY. if I can't get any "pro rated" warranty on these two, my plan is to visit the JY for a couple to go into the 95. at least for the time being. I used to have one of those old midtronics testers that would tell you exactly what condition the battery was in, but it's long gone. I need to invest into another one. The one I had was an old school one with a gauge rather than these newer one that have a digital readout. Lost it during a move.
 
While at the JY, sometime, if You happen across about a 95, how much older IDK, and it has the PS pump with the regular old fashioned hose connector and valve on the back of the PS pump, I will pay You dearly, in cash, for that set.
The JY, only one, over here, has a love affair with their GM trucks, and especially the 6.2 and 6.5 units and they are not willing to depart with any piece nor portion there of.
They have three suburbans, with roof racks, I called about buying a roof rack, nope, we dont have any suburbans and we dont have roof racks for them.
I have managed to buy a window from them for the 08 Maliblue but thats been the extent of it.
Oh yeah, they will allow not one person into their yard. Dont even ask.
 
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