Good afternoon gentlemen,

I have a 82 Z28 with a 86 305 carb engine...

This vehicle has multiple issues but lets strat with my major problem which appears to be overheating...

When i start it up in the mornings it runs great for approximately 8 miles down the road... I am driving in stop and go traffic approximately 35 to 50 mph. It is hot down here average temp outside is 95 degrees with humidity feels like over 105. The engine completely dies on me... I get out to inspect why and see very little water escaping out of the Radiator cap... I bought a new on that has 16lbs of pressure b4 it releases... i do not have a overflow container, the hose that ran to overflow container is blocked off with a bolt and hose clamp. I installed yesterday a new 180 degree thermostat, new Water pump, and all new hoses! I flushed the system twice b4 changing the parts out... has 100 percent concentrate AZ brand green coolant less what water that still remained in engine about a gallon and half of coolant. I replaced the Temperature sending unit in the driverside head. From cold start the Temp gauge works, however when the car dies on side of road after 8 miles of driving it, i let it cool down for 15 min and it will start right back up with no problems but the temp guage now reads about 120 degrees and climbs up to that mark very slowly...

Another thing i noted when the car dies is the Fuel filter i have is supose to be a racing clear filter... It is empty! I get no gas in it while the engine has overheated and i am thinking that is why the car did die on me... after that 15 min wait on the side of road i turn it over and fuel begins flowing again... I can drive it for roughly another 3 miles before i loose fuel to the filter and obviouslly the carb... Another 15 minute wait on the side of the road and then the fuel starts flowing again... last week i replaced the Mechanical fuel pump with a new one, i replaced all the fuel lines and wrapped them with some heat reflective tape to hopefully prevent vapor lock and keep the rubber fuel injection lines cooler all the way from the aluminum lines end below the AC condenser to the fuel pump, then from pump to the fuel filter and so on to the Carb...

When i bought the car it came with a non ccc Qjet that hade cast stamping from a buick... I purchased a 1406 Edelbrock carb and seems do be doing fine under normal operation until it gets HOT!

I tried to do the timing with timing light to find that there is a new timing cover on the block and the markings for TDC are missing... I can see the marking on the harmonic balencer but nothing to line it up with... So set timing by ear...

The distributor advance on the carb has timmed port and continuous vacume port... i do not know for sure which one i should be using but i have the vacume line connect to the timmed vacume port on Carb.

The engine has a small taping or rattleing noise only when it gets hot at low rpm acceleration and goes away the more rpm (again only when it is hot)

I have smoke coming out of pipes, My father tells me it is running lean... again i adjust the two mixture screws in many different settings and does not change much for the smoke issue... When it is hot i can smell the exhaust bad!

There is no EGR valve... It is covered with a Fuel pump plate and sealant...
The EFE valve is still there and the valve does opoen and close by physically moving the rod and i have tested the vavle to see if it holds vacume at it works, however the vacume is disconnected...
The air system is completely gone! The air tubes coming out of the exhaust manifold have been cut and pinched.
The o2 sensor is in the exaust pipe but no wire connecting it.

There was no charcol canister and the vapor line that used to go to it was connected to the vacume port on the Cruise contol valve located behind the driverside headlight... When i removed my gas cap i had back pressure that literall y pushed the cap off and into the palm of my hand... the sound made me feel like my gas tank was gonna explode with all that pressure... I then bought a new Charcol cannister and ran the line straight to canister and then put a T in the line from the carb to PVC valve so the carb can suck those fumes from cannister into it... (Know this is not right but had to try something, with out the air system being there dont know what else to do... the 1406 edlebrock carb does not have a port for charcol canister)

Hmm the list goes on and on... but i think this is a good start... please ask away so i can fix this overheating/ fuel problem...

Thanks to all in advance to whom contribute to aiding me in a solution... It is greatly appreciated.

 

here are some pics... If you need to see something please ask and i will post some more.

 

Oh i might add the lower shroud to the fan is missing but the air dam is still on the car and in good condition.

 

You really need an overflow on your car, even if its like a rubber hose into a half filled used Anti Freeze bottle (drill a hole in the cap and run the hose into it and put a dab of RTV until you can get a real catch can).

What color is the smoke coming out of the tail pipe? Is it white?

You need to run 50/50 water and antifreeze. Water is what cools the engine, the antifreeze just increases the boiling point and creates a solution that lowers the freezing point.

When the car is COLD, run the engine with the radiator cap off for a bit to purge the air from the system. Look for bubbles in the coolant while you are doing this and if you have a thermometer, stick it right in the coolant.

Something tells me your gauge or your temperature sender may not be accurate. I had this problem with aftermarket senders. I think I finally found an AC Delco or a Borg Warner unit that actually read correctly after changing it out like 4 times.

 

I am having the same problem and I see that the last time any body has podted on this was in 04 so PLEASE if any body has anytheing to ad let me know !!

 

UPDATE!

I went to Junkyard and got a lower shroud for fan (belt driven w/clutch) and a overflow container... It appears that the two or one or the other did lower the temps by roughly 5-10 degrees... I did a prestone flush in the heater hose T adapter... Flushed 3 times and there was more junk in there than i imagined... I replaced lower and upper hoses from rad and heater hoses as well. I then bought that high performance 180 degree stat from Mr Gasget... The fluid is 40% green coolant and 60% water.... So far my temps have been no higher than 240 at worse...

The Mechanical fuel pumps still goes out at this hot as if the diaphram inside of it stops working until 15 min on side of road and it cools down and then the pumps starts puming fuel again... I finally decided to do away with the mechanical pump and installed a Electric one that has not failed once all week no matter how hot it gets!

I Blocked off the return line to gas tank with a small 4" hose with a slightly larger bolt and hose clamp. It is leaking gas slow drip... Need any ideas how to block it off without the leak... Does anyone know if that will adversly affect anything outside of a fire?? I do have pressure in gas tank again seems to be normal pressure... Does anyone know how many lbs of pressure should be in the gas tank?

I also filled the cavity where the mechanical fuel pump was mounted to block with grease and put Mr gasget crome block off plate there.

My air Damn is installed, the ground affects are off, there is a slight bend in the plastic on the damn however it is very minimal... I will work on getting a new one of those as well just to be 100% certain because i do plan on putting the effects back on...

My other problem is the Temp Guage in the dash works correctly only in the mornings or shall is say until i shut off the engine for the first time... For example, i start it up in the morning to drive to work, the guage works fine, if i stop for a cup of coffee or gas, turn it off, then get back in and start back up the guage resets back to 0 degrees and never rises above 100 never again no matter how many times i turn it on or off... Only in the morninngs providing i never turnb it off does it work correctly... I replaced the sending unit 3 times now and same results... Any ideas?

The smoke that comes out of my exhaust is White... I am almost positive that the timing is off and contributing to my heating issues... Possibly running lean as well but can't be for sure.... I cannot find the markings on the head to set the timing... is there anything that i can do to get the markings back on? is there a bracket of some sort? I can see the one on the harmonic balancer but nowhere else... What do i do to get this thing timed right without know where TDC is at???

Last question is the radiator cap? I bought a 16 lb that has a pressure release lever... I noticed that when i leave the lever unlocked or in th up position i stay 10 degrees cooler than with it down and locked. Is that a good one to have? Should i lock it down?

I seen a cap from Mr Gasget that cost 25 and has a temp guage on top of the cap? Has anyone bought these and what is your findings and thoughts?

 

White smoke from the tailpipes, especially at startup, indicates that you might have a leaking head gasket or possibly a crack in the head/block. The coolant seeps into the cylinder at night and when you crank it up it may run really rough and shoot a lot of white smoke out of the pipes.

You will be also experiencing coolant loss. You can confirm this with a compression test, as the affected cylinder will have a much different reading than the rest of them.

Of course, the smoke may be burning oil but usually you can smell the difference.

 

if you're running lean or your timing isnt set far enough advanced then that is probably a huge part of your overheating.. the tapping youre hearing is your valves more than likey, symptom of overheating.

.to find TDC pull #1 spark plug, take a piece of coat hanger and put it in the hole. remove the valve cover and turn the engine over (by hand), while watching the valves for #1. as the piston pushes the coathangar up after the intake valve opens you will know you are on #1 compression stroke...then mark your timing cover where the mark on the balancer is, this will be 0tdc. If you find top dead center while the exhaust valve is closing, thats the exhaust stroke, rotate the engine one complete rotation until the intake valave opens. set timing aoubt 1/4 inch before that mark as the balancer passes.. i think that should be somewhere around 6-8* thats a good place to be if it idles to high then retard accordingly..

as far as your temp guage, do you know for certain its over heating? its sounds to me like it may be grounding somewhere, mine used to do the same thing. go ahead and check the wiring, its cheap and in the long run worth it. then you might want to think about getting an after market gauge to be safe.

and then about the fuel pump. i would honestly say that you should keep the mechanical pump if possible. did you ever disconnect the filter when the car died? i have a feeling fuel would have rushed out if you had, and if you ran it with a clear line without the filter you would have seen bubbles flowing through.. i had the same trouble on a k10 i used to own.. this makes me believe your car IS over heating. it heats the bowls and you end up with an excess of vaporization in the bowls vaper locking the pump so on and so forth; after letting it cool the vapor would condense allowing fuel to flow freely again. i would HIGHLY recommend staying with the mechanical pump. if you're hell bent using an electric pump make sure and use a regulator.. i think edelbrock says 6.5-10psi? somewhere in there.. not to mention it will more than likely flood with out one..

also, remember a carb doesnt use most of the original sensors the 86 would've had (o2 being one) so dont be worried if alot of them are unplugged(same with the air components). there should be a vent line on the tank, is that in good functioning order? if its pinched that could be the reason for the pressure in the tank... keep us posted on what happens, hope this helped