I have a 1968 Firebird 400 with a 402 bbl. I backed it out in my drive and left it idling while wiping it down. After approximately 5 minutes I heard an awful grinding sound with smoke coming the engine. I immediately turned the key off popped the hood and found a small oil spatter on the passenger’s side top of the firewall.
This one is a mystery because after further visual inspection there are no leaks and nothing looks broken.
I did see a drop of oil at the bottom of the starter. I mentioned this because the starter sometimes does not engage and when turning the key, It sounds like it just spins and grinds but it does engage after a second attempt.
I do suspect the starter; however, where did the fresh oil spatter come from?
I’m hesitant to try to start it again due to causing further damage.
This is the type of thing that needs in person diagnoses but I can steer you a little. If you're lucky the noise was from a bad alternator or water pump bearing and the smoke was from a belt. remove the alternator belt, spin by hand and listen and feel for bearing roughness. For water pump do the same as well as grab ahold of the fan and try to rock back and forth, if it has play replace. I suppose it could also have been the starter hanging up but doubtful and the smoke component would not be there. As far as your starter problem this is either caused from it being improperly shimmed, a bad solenoid, or teeth being chewed up on the Bendix gear or the ring gear/flex plate or both. It takes further diagnosis to figure out.
A little in and out shaft end play on the steering pump is normal. There should be none side to side and silent when spinning by hand with belt loose. The smell of the smoke would tell you everything you need to know. Rubber=belts plastic=wiring, and burning oil smells just like it does out the tail pipe on a car or even a lawnmower. Also, one thing I forgot to mention about your starter not engaging on the first try is to make sure the two bolts holding your starter in are tight. If the knurling on the shoulders is worn off they tend to loosen over time.
OK - my next check is to verify loose bolts on the starter.
The grinding noise coming from the starter during startup is intermittent and I have PTSD now when I turn the key. If the bolts are tight, my next step is to get a new starter.
What is your recommendation on starter? The current one is a NAPA Premium 1.4KW and it doesn't look like a mini-starter. The part number is rubbed off on the sticker so I will have to wait until it is removed.
As I said before it's a 396 factory bored 402 and the numbers match a 72 chevelle or camaro.
It's obvious that the car is pissed that a Chebby engine was put in her! Just her way of expressing her dissatisfaction!
I used to be indecisive. Now I'm not sure. I feel like I am diagonally parked in a parallel universe. 1968 400 convertible (Scarlet) 1976 T/A - 455 LE (No Burt) 1976 T/A New baby, starting full restoration. 1968 350 - 4 speed 'vert - 400 clone (the Beast!) 1968 350 convertible - Wife's car now- 400 clone (Aleutian Blue) (Blue Angel) 2008 Durango - DD 2008 GXP - New one from NH is AWESOME! 2017 Durango Citadel - Modern is nice! HEMI is amazing! 1998 Silverado Z71 - Father-daughter project 1968 400 coupe - R/A clone (Blue Pearl) (sold) 1967 326 convertible - Sold 1980 T/A SE Bandit - Sold
Glad you found it. did not know you had a/c but that is what I was getting to by having you take belts off and checking the driven accessories. Although not great your finding is much better than having the noise come from the engine itself. Good job.