I have a 1979 4 bolt main 350 engine in my camaro, its had been rebuilt but i have 4 bolts on my engine that have screws half way out...i need to know what they are.... ( not the motor mount plate bolts)

i put a picture i found off google and i circled the bolts..but mine just has a bolt sticking half way out of each. the top ones leak. --- my questions are......

1.) do i plug them? and if so, could a bolt be to long? and do i need thread sealer?

2.) do theses bolts have to do with accesories like a gauge for oil temp? if so i have a oil temp gage, but were do i put the sensor? and like stated before could the sensor be two long???????? let me know please, i will be puting the engine back togeather tomorrow.

THANKS!
-Matt

 

the bottom one might be the knock sensor, your gonna need that. I'm not sure about the top one, sorry

 

A knock sensor in a 1979 motor?

 

the bottom one is a coolant drain hole, not a bolt hole. it's NPT threaded, not UNC. The factory used this for the knock sensor w/ EFI equipped cars but the hole was always there on earlier castings. Normally they have a plug there which can be removed to drain all coolant. The petcock there is something the rebuilder does.

the other hole is used for a support strap for the starter

 

Correct, except the later computer carb models, and the L69 carb engines, also had the knock sensor (not limited to EFI).

Correct. If it is leaking, I'd guess someone installed too long of a bolt and punched a hole into the coolant jacket. Not a big deal if you can get it to seal. I had heads that leaked from the exhaust bolt holes (too long of bolts used, punched a hole into the coolant passage), I just put sealant around the threads to keep it from leaking. As long as the outer block wall isn't cracked, you should be able to do the same with the top bolt hole in your block.

BTW, that accounts for 3 holes. You said you have 4 you are wondering about - what's the 4th one?

 

If it's on the other side, it's a thread used for a mechanical clutch pivot stud.
Forgot about the CCC arbs, yes, they too have an EST/ESC system.

 

You're probably right, but it isn't in the same location as the picture posted.

 

No it's closer to the filter pad.