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So I pulled my valve covers today on my 66 Jetstar. 330 btw. Driver side seemed okay, and the passenger side is quite rusty. I’ve never messed with engines before so I don’t know if it’s safe to put back together and run for the time being.
You wouldn't be sure until you at least had the heads off. That rust looks like it is from condensation not immersion. You might dodge a bullet and only need to address the heads.
It would be nice to see the hardware w/ less caking; yet, to your question - is your engine cooked?
A brief review demonstrates you purchased the car last year; and, it's a nice car.
To the point:
Does the engine run? Has the engine been tuned in compliance with the Oldsmobile Chassis Service Manual (CSM) specifications? Maybe the engine/car sat for some time before you bought it contributing to what appears as moisture & fouled oil. Don't give up the ship quite yet.
First step. Get yourself a compression gauge and perform a compression test. It is a very simple test which will provide you w/ knowledge of the overall health of the engine. Tons of literature & videos available on performing a compression test - do your research. I'll note it's far easier (especially on the starter/ignition) to remove all spark plugs. Come back w/ the results of the compression test & members can provide plenty of advice.
You wouldn't be sure until you at least had the heads off. That rust looks like it is from condensation not immersion. You might dodge a bullet and only need to address the heads.
^^x2^^ Could be likely nothing more than lots of condensation/moisture which contributed to the fouled appearing oil. A compression test will determine overall health of your engine.
Depends on what you consider "cooked". I would want to know if any oil is getting to the rocker arms on the passenger side head. You'll still need to remove rocker arms and push rods to wire brush them to remove all the rust.
x3 on doing a compression test. If the engine has good compression go ahead and run her. You'd have to do a cylinder leak down test to determine if the valves are leaking excessively.
Alright lads, getting a coffee. Then going to grab a compression gauge, will test tomorrow.
background on the car, guy before me own it from most of its life and barely drove the car. The radiator cracked when I drove it home, I replaced it with an aluminum on and did the hoses and tstat last year.
Since then, I haven’t had funds to do much. It sat a while. My dad and I got it out for a short drive about 6 months ago.
Currently I have new spark plugs, a new carb, some valve cover gaskets, oil and filter, trans fluid, and a ton of cleaning products. I will say, being in Arizona, I doubt much of the rust occurred since I bought the car. Which means I was running it in close to current condition, and it seemed fairly normal running.
Today I will be pulling the rockers and pushrods to clean, do I need to track where I pull them from and put them back in the same place or?
Yes, the rocker arms and pushrods should stay with the same valve & lifter. Also, make sure you don't flip the pushrods end-for-end.
^^x2^^
Get a single piece of cardboard. Make holes in the cardboard to accommodate the push rods. Number each hole w/ a marker. Insert each push rod into it's appropriate/designated hole as they came out of the engine w/ the same orientation.
I’ve never bothered putting pushrods back where they came from or orient them, same with rockers. Only thing I do is keep bridges matched to rockers, having said that it’s not a bad idea to put things back the way you found them.
FWIW, when I owned my 64 98 as a broke college student the 394 developed a rocker arm tick. I found a 64 Dynamic 88 with a 371 in the salvage yard and got both of the rocker arm shafts and all 16 rocker arms off of the engine. I mixed and matched all 32 of the rocker arms I had for a good set. Necessity is the mother of invention. 🤔
And pull the pushrods and make sure the hole in them is clear all the way through. Carb cleaner or brake clean with the little red tube works good for that.
Alright, everything is clean. I did spray the pushrods as two were clogged and some others partially clogged. I’m unsure of how to clean the gunk out of the heads. Pulling them isn’t really an option right now.
Alright, everything is clean. I did spray the pushrods as two were clogged and some others partially clogged. I’m unsure of how to clean the gunk out of the heads. Pulling them isn’t really an option right now.
any tips or ideas?
Poke a wire down the drain holes. Be aware there could be slight mismatch of the drain holes near the deck surface. Mark the wire to know when you got to the valley area.
At this point you might as well put it back together and give it a shot. You cant really make it any worse. I would probably change the oil a few times maybe every couple of hundred miles ? Or at least change the filter and add a qt.
Agree. Clean best you can. Take it on several long highway runs of 50 miles each. Change oil & filter at 100 miles & 200 miles. Get and keep the engine hot. Most of that is moisture laden carbon fouling which is likely to simply degrade via pyrolysis. R&R valve cover gaskets again ~300 miles have a “look see”.
Having mentioned you aren't experienced with engines...all friction surfaces get lubed as part of the assembly process, nothing that slides, sits on or spins on other metal surfaces is left dry. If this was a full rebuild, engine assembly lube would be in order, in this situation just make sure everything is well oiled. You could SLOWLY pour the oil over the valve train/pushrods and rocker arms with the valve covers removed vs. through the oil fill tube.
Look in the oil fill tube for a screen at the bottom, mine was so clogged on my '64 330 it was difficult to add oil!
thanks so much for the tips and help, you guys are great.
Tomorrow’s To Do’s:
Set Valve Lash
Replace Carburetor
Instal Valve Covers
Compression test
Replace Spark Plugs
Run engine oil flush, Oil/Filter Change after
And lastly Plug up the Smog ports
If you guys have any tips for these tasks, I’m all ears.
Thanks again friends
Last edited by BraydenU; May 30, 2025 at 07:08 PM.
The valve lash isn't adjustable on this setup. Rotate the engine by hand so that the camshaft lobe/lifter/pushrod is on the flats of the camshaft for both pushrods on the cylinder you are working on and then torque the rocker arms in place, done. Torquing the rockers in place with the camshaft lobes raised increases the chance of breaking the rocker arm support.
The valve lash isn't adjustable on this setup. Rotate the engine by hand so that the camshaft lobe/lifter/pushrod is on the flats of the camshaft for both pushrods on the cylinder you are working on and then torque the rocker arms in place, done. Torquing the rockers in place with the camshaft lobes raised increases the chance of breaking the rocker arm support.
Clarification ? You want both cam lobes180 degrees from the highest lift. This can be called the "base circle". you don't want any pressure on the valve train.
at this point you might as well put it back together and give it a shot. You cant really make it any worse. I would probably change the oil a few times maybe every couple of hundred miles ? Or at least change the filter and add a qt.
Agree don't raise the white flag yet. Can you get a cell phone borescope and look in the cylinder?
Agreed !
Sugar as per below, and the fact that I don't recall him mentioning a white smoke issue, this just happened ...
Originally Posted by BraydenU
background on the car, guy before me own it from most of its life and barely drove the car. The radiator cracked when I drove it home, I replaced it with an aluminum on and did the hoses and tstat last year.
Since then, I haven’t had funds to do much. It sat a while. My dad and I got it out for a short drive about 6 months ago.
Brayden, 330s are incredibly resilient engines. And there is a direct correlation with a blown head gasket and a cracked radiator. Limited use under these circumstances is the key towards its survival...
Car is running. Sounds ehh, power underwhelming. We did not replace the carb just tightened everything up. Which stopped the leaking bowl significantly.
New valve covers/gaskets so I’m not leaking oil on my exhaust headers. Nice.
Valve train is all done up, torqued to 25 ft/lbs at cylinder TDC.
New Spark Plugs.
Cylinders 3/5 leaking the coolant, not ideal.
Did an oil flush and then changed the oil and filter, spray sea foam all over the valve area of the head(Where the rockers are, technical term??) No coolant in the oil, ideal.
Removed the smog system. Did a little ghetto but it’s okay I have bigger fish to fry.
Installed new hood hinges, wasn’t able to get to the spring to install the hood before the AZ sun got to us.
Filled the radiator up, tighten the cap for an overflow/expansion tank(whatever it’s called) which I must have loosened/didn’t install correctly, drove the car for 10 minutes or so. Level lowered about 2 inches, some due to refilling what was lost in the block so maybe not a terrible leak. I bought some CRC head gasket repair. Will run it through the radiator tomorrow and cross my fingers. I’m hoping it’s just a head gasket crack between cylinders 3/5.
Anyways, your guy is mad tired from baking in the sun for three days. Giving this car some love, things didn’t turn out exactly how I wanted but I learned a lot and got out there.
thanks again for all the support, advice, encouragement, etc. You guys are life savers. Oh and here’s a pic of my engine bay, that I was hoping to have all cleaned up by now but didn’t get around to it lol
Last edited by BraydenU; May 31, 2025 at 06:36 PM.
If it were mine I'd pull the head instead of using the head gasket repair liquid.
Keep up the good work!
I was ready to do some, but my dad made the point of keeping it driveable until I can clean out the garage and get the car parked inside. Otherwise it’s big engine work in the street.
Originally Posted by 69CSHC
I bet, just looked up your current temp. A nice round 100... and it's still spring.
Nice work !
Oh yeah brother, it’s toasty over here. Luckily today was a teeny tiny breeze and a bit of clouds keeping us safe. It really is no joke though hahaha
