87 tbi hard turning over

[87 grey ghost]

Hello
I got an 1987 gmc tbi 1500 pickup.
It cranks over really hard and after one try of cranking for about 6 sec the battery dosn't have enough juice to crank it over again!!! The battery is brand new and a good cold cranking amp.
Also it's an automatic and has bin making some noise like an engine knock but it's not the engine. ( mayb a bad starter or something from the torque converter) thanks for any help

 

[87sierra]

first of all start by checking the connections at the battery terminals that they are clean and tight next go to the start make sure you have good clean connections there to also check the ground from the battery to the radiator support. another thing to do is check resistance through the battery cables if you have a volt meter

 

[87 grey ghost]

Yes that's all good.
If I spray carb cleaner before each start
It'll fire right up??

 

[StickDeath]

Is the motor Cranking and then locking up a little? And are you having a hard time starting it after you have driven it. my starter was heating up in traffic since i have longtubes. and i had to put a heat shield on it.

 

[Jims86]

Yes that's all good.
If I spray carb cleaner before each start
It'll fire right up??

If it is an extended start, the fuel pump relay is probably toast. Look on the relay plug on the firewall, and if you see a red wire with an end on it, thats a direct line to the pump. run a wire fromthe battery, to that wire, then see if it fires up like it should. The relay is onlythere for the 2 second prime, and the oil pressure switch takes over for running.

 

[Eric Sprouse]

My '87 Silverado won't restart after a short drive after putting Hooker Ceramic headers on. I called JEGS and they said the solenoid is overheating. I bought their starter wrap but it doesn't work. The headers and starter are very close together ! What are others doing to solve this dilemma ?

 

[4WDKC]

My '87 Silverado won't restart after a short drive after putting Hooker Ceramic headers on. I called JEGS and they said the solenoid is overheating. I bought their starter wrap but it doesn't work. The headers and starter are very close together ! What are others doing to solve this dilemma ?

Headers generate alot of heat and it can heat soak the starter, plus thats probbaly the original starter, you may want to look into what it would take to swap to a newer starter or a mini starter.
I have a high torque mini starter on y vette with uncoated headers and it has no problem starting it.

 

[Eric Sprouse]

Thank you ! I will try the mini and even wrap with the starter insulation from DEI.
Is you starter wrapped ? JEGS said its the solenoid overheating more than the starter.

 

[4WDKC]

Not sure I would believe that if the starter isnt spinning over. Mine is not but it aftermarket one.

 

[Rusty Nail]

I would verify integrity of the connections prior to spending any money.
There isn't any reason to have starter "heat soak" troubles with a square body Chevy in 2018...I believe something else may be amiss.
It's likely something you very recently touched?

How bout them battery cables?