Update on KJ's truck/carb problem

Thanks group. My truck is running, insured, and inspected. I however do have a vague problem, so I will detail all that I know about it.
1985' Chevrolet K5
305CUI SB bowtie power plant TH700R4 transmission - used from a 1983 GMC Jimmy NP203 transfer case - original
Recent Repairs: New front brake line, from proportioning valve to flexible brake line. New transmission cooler lines (too and from) Three new U-joints (both on rear axle, front on front axle) New: oil, tranny fluid (transmission and t-case), new oil filter, air filter, wipers For more detail on these repairs see "Update on KJ's truck/Vibration Problem"
Carburetor repair: Used a machine screw and nut on the choke pull-off vacuum diaphragm to make it actually open the choke. Dismantled the entire carb, and generally cleaned. This was to get a better understanding of how this particular carb works (though I know well how carburetion works in general)
The wiring to control the choke is suspect, so if anyone would like to send me a wiring schematic of this assembly, I'd like to inspect it.
I did re-use the old gaskets, and that couldn't be helping my problem.
Ignition "repair": The plug wires appear to be in working order, and clean. It is a new (looking) delco-remy distributor. I haven't pulled the spark plugs yet to check what condition they are in. I don't know if the timing is perfect or what as well. A friend of mine who was trouble shooting a very high idle first closed the choke, and that helped a lot. Then he adjusted the distributor to slow it down a bit more. This is - from what I understand a no-no. I do know it's not knocking, and it has balls so it can't be too far off. There is however a vacuum diaphragm hanging off it that is stopping it from turning counter clock wise any more.
Problem: Truck starts hard when cold. It just reminds me of my Malibu, like if it had some more choke it would start right up (Malibu had a manual choke, so I'd just add more) It starts, revs a little higher then idle and then settles down and dies, like the choke is taken off too early. I haven't had someone start the truck while I was watching to see the operation of the choke.
BIGGER PROBLEM: I have little experience in this field. I definitely know what the usual first question is (and what I'll probably still get) NO I do not know if the vacuum tubes are good/correct. Right now, I can look under the hood and say "yup, there be a shit load of vacuum tubes under there." But there are a lot that aren't looking so hot, or have been cut and plugged, and a lot of nipples that have some kind of cover over them, and a lot of suspect nipples that don't Truth be told I don't know how this should be hosed' so I can't tell if there going where they should. If someone could give me specifics, of common-failing hoses that could cause this, and if I need to do more than spray them with WD-40 to check them, that would be awesome.
http://www.geocities.com/hawkeye649box/k5.html has pictures of my truck
http://www.geocities.com/hawkeye649box/blazer00.jpg is a picture of the engine compartment
Doesn't show much of the hoses, I can get a clearer picture of them if anyone cares.
Thanks for any help
-The Lonely Grease Monkey 1985' K5 305CUI TH700R4 NP203 KJ's successor
"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson
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Are you sure it's an NP203> 203s are full time, I thought after 81 they used NP208.
A couple things to check for vibration, after you get the lug nuts and wheels looked after. Both drishafts have a spline, which when worn will shake. They need to be greased regularly. Unscrew the collar at the spline, hold something over the hole in the end of the shaft, and pump grease till it comes out around the loose collar. Moly grease is preferred.
I had a bad fan clutch bearing in my 78, shook at random speeds and conditions. Took me a long time to find it. I'm betting on wheels.
I don't understand about the machine screw and nut on the vacuum choke pulloff. It should only pull it open a bit, to lighten the effective choke spring tension, untill it warms up.
The base gasket will shrink out from under the carb, as there are phenolic washers in the corners to prevent warping the carb. This gasket should be replaced preiodicaly, but I can't tell you how often. I had a Grand Prix that would stall at every stoplight until I changed it. The choke housing should get pretty hot, and pull the choke open, as the engine warms. If it gets hot and doesn't open the choke, the bimetal spring may be broken. The secondarys should not open until the choke is almost fully open, as the choke linkage locks them shut. Dan
ly G-Monkey) wrote:

Colorado Springs, CO My advice may be worth what you paid for it.
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Your t-case is a NP208 (aluminum housing) not a 203 (steel housing) If (by your website) you took out the t-case by yourself it was a 208, or you are one giant of a guy to take out a 203 by yourself....
But anyhow, get yourself a can of spray ether (diesel cold start assist spray) then with your engine running, spray SMALL AMOUNTS near the carb and vaccume hoses. If there is a leak the engine will surge with the induction of ether. BEWARE: ether is extremely flammable and explosive, do not spray directly into the carb.

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FYI... I had a '71 Chevy K20 Pick-Up and did a R&R with the trans...with no jack. Also did the same with the T-case, an NP205 BTW!!! I defiantly don't ever wanna do it again, but it can be done. I would have preferred it to have been a 203, maybe 100lbs less.

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What exactly do you mean by no jack? On a drive way, no floor jack? Or on a lift, no tranny jack?
If the first, you must be an absolute beast, or a friend of the hulk... I needed to put the 203 on my crotch/abdomen, and even then used a floor jack to hold up the lobe of the t-case, and lifted it up by arching my back....
-The Lonely Grease Monkey 1985' K5 305CUI TH700R4 NP203 KJ's successor
"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson
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When it's at your strength limit, 5 lbs might as well be 6,000 tons. When I first put in my tranny, I lifted it up without the TC on the tranny, figured I wouldn't damage anything that way. Well I didn't - but I was too weak to lift up the TC to get it on the tranny!!!! Laying down, I just couldn't get under the TC to lift it, and I couldn't get my scrawny arms all out-stretched and stuff to lift it up....
-The Lonely Grease Monkey 1985' K5 305CUI TH700R4 NP208 KJ's successor
"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson
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G-Monkey, I was responding to Shades........

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Sorry for talking, I'll go kill myself now.....
~KJ~
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Huh........ I put that so you/ he wouldn't take offence..... but whatever........
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