The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   The 1967 - 1972 Chevrolet & GMC Pickups Message Board (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=3)
-   -   Spark Plugs What is wrong? (https://67-72chevytrucks.com/vboard/showthread.php?t=743895)

wesmigletz 08-12-2017 03:07 PM

Re: Spark Plugs What is wrong?
 
Just curious, you're running an Edelbrock carb. Are you still running a stock fuel pump, or a low pressure pump? Stock pumps put out too much fuel pressure.

special-K 08-13-2017 09:32 AM

Re: Spark Plugs What is wrong?
 
He has bubbles everybody.

I had a head issue I got through this time last year. I had a plug that was stuck, wrung it off flush, removed head(s), magnaflux found crack, better performance rebuilt heads, I'm a happy camper. Hopefully it's just a gasket for you. I guess my plug was rusted in from coolant. Truck never smoked and ran great till I broke the plug while removing to take the header off to access the brake line/hose union better. Talk about a snowball! Good luck!

Steeveedee 08-13-2017 11:39 PM

Re: Spark Plugs What is wrong?
 
Quote:

Originally Posted by AussieinNC (Post 8009979)
Do the spark plugs screw into the heads at 90 degrees to the head or are they angled off center ?

Taper seat or (peanut) plugs are meant for heads that have angled spark plug threads....if the spark plugs thread in at 90 degrees to the crankshaft, these plugs are the wrong type...they may be the same as what was in there, but that doesnt mean they are correct...

Post a pic of the side of the head showing the plug without the boot ....thanks

:chevy::chevy::chevy:

I'm pretty sure that beginning in '71, taper seat plugs were used on SBCs, and went straight in, not in angled seats.

greasemonkey 08-14-2017 10:05 AM

Re: Spark Plugs What is wrong?
 
Quote:

Originally Posted by special-K (Post 8015477)
He has bubbles everybody.

Apparently we're the only ones besides the owner that realize his engine troubles go a little deeper than fuel and spark.

AussieinNC 08-14-2017 03:38 PM

Re: Spark Plugs What is wrong?
 
Yep...he has a constant bubble stream in the radiator...obvious water ingress into at least three cylinders...and an engine running like KRAP...

Pull the heads and take a look...

Post a pic of the heads once they are off...

Then we can all see what the issue really is...

:chevy::chevy::chevy:

Its a Chevy...its not rocket science...

:fb::fb::fb:

53chevyforever 08-14-2017 11:04 PM

Re: Spark Plugs What is wrong?
 
Yes..thanks guys for all the comments....I am presently working on wiring....
soon will pull the heads...will let everyone know what I find...thanks...Tim

snipescastle2 08-15-2017 12:00 PM

Re: Spark Plugs What is wrong?
 
You can confirm the presence of combustion gases by having a shop place their emissions analyzer sniffer above the filler neck, if "HC" readings go up, bingo!
Not all head gaskets leak coolant into the oil, some leak into the intake passages. I'm surprised this engine isn't running hot....if you cannot maintain system pressure in the radiator, the boiling point of the coolant goes way up, placing a vacuum on water does just the opposite, lowers the boiling point.
That's why you keep a pressure cap on the radiator. 15-16 psi is normal, should raise the boiling point to 230-240 degrees.something like that.
You haven't noticed any unusual smoke/steam coming out from behind when you accelerate have you?
Hope it's an easy fix, I'd be looking for cracks in between the combustion chambers or maybe it's just a gasket issue.
Hth,
Ben
:metal:

davepl 08-15-2017 01:06 PM

Re: Spark Plugs What is wrong?
 
^^^ This. I've used a buddy's SnapOn emission sniffer for this. I put it on CO (not HC, though maybe either works) and sniffed the filler neck, and even in a car where the leak was slight enough that there were no visible bubbles, the CO count would shoot up when placed over the filler neck.

snipescastle2 08-15-2017 02:00 PM

Re: Spark Plugs What is wrong?
 
I stand corrected! Knew it was one of the two!
Ben


All times are GMT -4. The time now is 04:22 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright 1997-2025 67-72chevytrucks.com