What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

87 K5 problems

I

iweb

Registered Member
Joined
Aug 26, 2007
Posts
22
Reaction score
0
Location
Nevada
I traded for an 87 K5 a couple of years ago that was just rebuilt, 350 motor, 700r tranny, 15 bolt rear end, etc. It has been sitting and I start it every couple of months and run it around the yard for 10-15 minutes. I have stabil in the gas.

Had to put charger on boost to start it, cranked forever and finally started, tried a few times before it caught like a flooded carb acts. Ran good then started running rough like not all cylinders were firing, and either blowing smoke out exhaust pipe or saw it because temps were around 30 degrees. Shut if off and tried to start it and battery was too low to turn it over. When I unhooked positive cable the bolt was so hot I couldn't hardly touch it.

Pulled one CR43 TS spark plug and it is dry but black, truck has headers.

I am going to get new plugs, are these the right ones with the headers? .035 gap? I did a search on here and read for hrs yesterday.

Any idea why battery post bolt was so hot? With key off, radio off, amp unhooked, I get a pretty good spark when I touch the cable to the post.

Hope I didn't blow a head gasket, no water in oil and coolant looks normal except a couple of inches low in rad. and bottle is empty.

Thanks.
 
Low voltage can cause the starter and cables to overheat beleive it or not....probably it was hot just from cranking it so long--the heavy spark could be you had a short draining current somewhere...the white smoke sounds like an ominous indication of burning coolant,but a lot of condensation could have been building up in the muffler & exhaust pipes too--if you find a spark plug thats much cleaner than the others,(that might even have some green coolant on the electrodes),then you can be sure its a bad head gasket or cracked head ,block,etc...hope its not that!..
Sometimes this new gas with ethanol goes sour rather quickly and absorbs water too,and Stabil wont always work in that gas unless you use the Marine formula,I have seen cars with bad fuel injectors smoke white like crazy till the flooding condition is fixed...stale ethanol gas usually makes an engine start hard and it gums up carbs fast,that can cause rough running..what sucks about EFI is the fact you cant just run the engine off a gas can like you could with a carb to see if bad gas is the trouble..
 
I'm only guessing here, but it sounds like maybe the fuel might be a bit bad, combined with the computer maybe forgetting it's settings? Not sure if that's possible, but it's my theory.

Especially with a dead battery, I could see maybe that it's running rich, and with questionable fuel, that may be adding to the trouble. I bet with a full battery it will fire, run bad for a bit until it warms up, and then start to run better. A good drive will probably help too.

As for the spark, well, with low voltage, the amperage goes up to power stuff. So whatever might want some juice while it's "off" will be trying to get whatever power it can.

Again, this is just my thought on your issue. Good luck, let us know how it works out.

Clay
 
Is the CR 43 TS the right plug with headers? Gap .035?

Bad gas is probably the problem, when I first got the Blazer it ran perfect and started up when I hit the key then slowly got worse and worse with starting hard and running rough.

Every since I got it, when it is running the volt meter needle on the dash pulsates from 1/2 to over full value and the headlights pulse the same, like a heart beat if that makes sense.
 
It sounds correct for an EFI small block,I'm more used to older carbed trucks using R45-TS plugs though...

The "pulsing" of the altenator voltage may be due to a corroded connector at the altenator ,if the wire that senses the battery voltage doesn't have good contact,it will "tell" the regulator to put out more volts & amps ,it could be a short circuit somewhere in one of the unfused wires in the harness,or simply be a defective voltage regulator inside the altenator,or a bad winding in it..a bad ground can cause that too,not only under the hood,but the ground wire to the dash that grounds the cluster...
 
You must log in or register to reply here.

Latest Posts

Top Bottom