Knockin' On Heaven's Door, what to do for a rod knock?

[ttype]

here's one for ya MrSony... i used to read a lot over at v8buicks... a lot! one thing i remember from all that reading is about "improvements" to the oiling system's process. as you may well have surmised, the rear sump pan is quite far away from the pump, and yes, increases to the size of that line helps reduce -negative pressure to the pump gears. but have you read or heard of an "equaliser" for the mains? it involves running a large braided line from near the oil pump to the last plug on the main oil rail?(feeding it from both ends at equal pressure). compare this mod to "voltage drop" by "externally" feeding oil pressure to the other end of that rail, the "drops" across the rail aren't so...added up. it's just an idea.

 

[pontiacgp]

I had a buick 350 engine once and that was enough for me.

 

[lilbowtie]

I've read that article 100 times. for a motor to grenade like that, I'm willing to be he wasn't "just driving". And as for why the rods weren't lubricated, I'd say 6,000rpm on a stock bottom end is what did it. Repeated 6k rpms, mind you. Not just whacking it once and it broke. Basically 5,000 miles of abuse.

I'm going to guess your break-in didn't do the bearings any good and with Buicks oiling it managed to make it 5000 mi. Buicks are hard to prime the oil system (even v-6) and you need to pack the oil pump. I always prime them before going in the car. It should be able to take 6000, my stock block has been in the car 7 years - shifts at 6200 and goes through the traps at 6200 and has over 800 pass on it (checking lash & oil change only) I've played with Buicks and did extensive mods to the oil system in my 455 to insure good oiling. My 70 was a car I thought I would never sell until a guy offered me stupid money for it.

 

[UNGN]

On my Buick turbo cars, if they had been sitting for a long time, I would take off the Turbo oil hose, put a hose/funnel on it and fill fill the oil pump from the top side, then reinstall the oil line (a hassle, but way easier than taking off the cam sensor/distributor and turning the pump with a drill).

 

[joesregalproject]

I'm going to guess your break-in didn't do the bearings any good and with Buicks oiling it managed to make it 5000 mi. Buicks are hard to prime the oil system (even v-6) and you need to pack the oil pump. I always prime them before going in the car. It should be able to take 6000, my stock block has been in the car 7 years - shifts at 6200 and goes through the traps at 6200 and has over 800 pass on it (checking lash & oil change only) I've played with Buicks and did extensive mods to the oil system in my 455 to insure good oiling. My 70 was a car I thought I would never sell until a guy offered me stupid money for it.

Packing the pump with grease is extremely important. They aren't terribly difficult to prime once they pick up oil. You can prime them with a drill and a big flat blade bit through the distributor hole. The oiling mods are important for even mild street/strip builds. TA Performance is the place to refer to for that. For a cruiser/driver, The oiling mods are a bit overkill IMO, but aren't gonna hurt anything.

 

[MrSony]

Yeah, I did the whole packing the pump thing with vaseline. Worked well. I just forgot those stupid little oil galley plugs on either side of the cam. I got the block back from the machine shop and just started going at it with parts. I was wondering what those two little cup plugs were 😛 But it was my first engine. What can ya do besides remember and laugh.

 

[pontiacgp]

Yeah, I did the whole packing the pump thing with vaseline. Worked well. I just forgot those stupid little oil galley plugs on either side of the cam. I got the block back from the machine shop and just started going at it with parts. I was wondering what those two little cup plugs were 😛 But it was my first engine. What can ya do besides remember and laugh.

If you broke the engine in with no oil pressure the engine would have seized up in the 20 minutes it takes to break the cam in....

 

[MrSony]

If you broke the engine in with no oil pressure the engine would have seized up in the 20 minutes it takes to break the cam in....

Miracles do happen. I think the oil was getting where it needed too, just not staying there. When priming the oil system (to be sure ifthe gauge was bad or not), you could see oil dumping out the holes either side of the cam like Niagara. Regardless of how or what it happened, it broke in just fine, and probably would still be running if I didn't get rev happy. I used moly paste (some of which is still on the rocker shaft), and the mechanical gauge read not even a PSI of oil pressure. Broke the motor in, drove it for a few miles, lifters started ticking, so I shut er down. Installed the cup plugs, got 50psi cold and 23 hot at idle. NEVER had any shiney bits in the filter or oil. Changed the oil three times. I did have a bad carb on there for a while (qjet) that dumped fuel from the well plugs. Oil was probably at least 40% gas, so that didn't help any. Been running fresh Valvoline 10w30 for the last 1000 miles with new rebuilt qjet.

 

[pontiacgp]

what were your bearing clearances when you put the engine together? and what do the bearings look like that you just removed?...

http://www.agkits.com/bearing-failure-analysis.aspx

 

[pontiacgp]

I'm going to guess your break-in didn't do the bearings any good and with Buicks oiling it managed to make it 5000 mi. Buicks are hard to prime the oil system (even v-6) and you need to pack the oil pump. I always prime them before going in the car. It should be able to take 6000, my stock block has been in the car 7 years - shifts at 6200 and goes through the traps at 6200 and has over 800 pass on it (checking lash & oil change only) I've played with Buicks and did extensive mods to the oil system in my 455 to insure good oiling. My 70 was a car I thought I would never sell until a guy offered me stupid money for it.

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Back in 69 my grandfather bought a 70 GS 400s, said that was the last 70 model Skylark the dealer had so he got stuck buying it.....