cudak888: 1972 Q-code - cam failure pictures

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Hard to make someone's mind up. But one thing I do know. There's way to much stress with building one car, I couldn't imagine two! Today I took mine out for a nice drive, although it's hot as crap. But I burned through about 5 gals of gas just cruising around. I still have A LOT to do before it even looks great BUT just driving it it and rippin through the gears is just a nice change from cutters, welders, sanders, and tools!!!

And I'm sure parting it out won't give back what you have in it.

Sent from my iPhone using Tapatalk

 
The dampers really don't increase the rate much. Those are the same springs used on my comp hydraulic roller. They aren't that stiff. They probably didn't A: use break in oil with zinc. B: didn't keep the RPM up or varied it.
Ok, let's go with the theory that the double springs aren't the cause of the bent pushrods.

If so, the next thing down the line would be the mushroomed lifters binding in the block - but if that were the case, wouldn't we have seen at least four valves smacked at cylinders #2, #3 and #7? At worst, we have two valves bent at cylinders #5 and 6, and zero indication of them having smacked the pistons.

It just doesn't make sense, and that's what bothers me. I am not going to start throwing parts at it until I know what caused the stock pushrods to fail - because they didn't fail on their own.

Furthermore, the break-in procedure is pretty much a case of the darn engine starting up right the first time - and to continue to do so for 30 minutes. No workie, cam wipey.

Funny thing, I learned this evening that at least one of the cams that came with the 400 (dare say not the '77+?) cam isn't that far from the 351C 4V:

351C 4V:

Lobe lift: Int 0.247 / Exh 0.262 /// Theoretical lift: Int. 0.427 / Exh 0.453

400 2V:

Lobe lift: Int 0.247 / Exh 0.250 /// Theoretical lift: Int. 0.427 / Exh 0.433

This will sound stupid, but I know I can dig up more than one 400 with matching lifters at the junkyard. Question is - truck cam or not? Who knows? Too many variables to be feasible.

Nah.

-Kurt

P.S.: On that note, it remains to be seen whether the lifters scored the block to the point of sleeving.
I worked on a 71 Grande with a 302 (25 K miles) for friend several years ago that had sat in a garage for 16 years without running. My neighbor started the car on the 16 year old fuel. The engine ran smooth and quiet for 30 minutes and then he shut it down. Upon restart it bent every single push rod which was due to all the valves seizing in their guides.I Removed the heads and had the guides done including replacing the pressed in rocker arm studs which had all puled out to varying degrees. My second experience with valves sticking in their guides was on another 302 of 1977 vintage in a friends boat. I do not like working on boats.

 
I worked on a 71 Grande with a 302 (25 K miles) for friend several years ago that had sat in a garage for 16 years without running. My neighbor started the car on the 16 year old fuel. The engine ran smooth and quiet for 30 minutes and then he shut it down. Upon restart it bent every single push rod which was due to all the valves seizing in their guides.I Removed the heads and had the guides done including replacing the pressed in rocker arm studs which had all puled out to varying degrees. My second experience with valves sticking in their guides was on another 302 of 1977 vintage in a friends boat. I do not like working on boats.
Don't get me started on boats - they make the cars look doable. Talk about your sinkable fiberglass project cars in salt water. That, and gasoline-powered boats are always at a risk for explosion - the gas vapors don't have anywhere to escape to in the bilge. One spark...goodbye.

That said, I don't expect to have that problem here with the heads redone. All things considered, I'm coming out of it pretty good as far as the heads go - $250 for labor to clean them up, surface them (.003" IIRC) and do a 3-angle job on both + $176 in new valves, locks, and retainers at my end = $426 total.

Of course, I'm going to pull the engine and check the bottom end, but I'd rather do the bodywork first. Engine is easy by comparison :rolleyes:

-Kurt

 
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I knew you were giving up on this particular car. But I still like your idea for doing an Eleanor clone.

I hope you find a worthy candidate in the future.

Ron



I worked on a 71 Grande with a 302 (25 K miles) for friend several years ago that had sat in a garage for 16 years without running. My neighbor started the car on the 16 year old fuel. The engine ran smooth and quiet for 30 minutes and then he shut it down. Upon restart it bent every single push rod which was due to all the valves seizing in their guides.I Removed the heads and had the guides done including replacing the pressed in rocker arm studs which had all puled out to varying degrees. My second experience with valves sticking in their guides was on another 302 of 1977 vintage in a friends boat. I do not like working on boats.
Don't get me started on boats - they make the cars look doable. Talk about your sinkable fiberglass project cars in salt water. That, and gasoline-powered boats are always at a risk for explosion - the gas vapors don't have anywhere to escape to in the bilge. One spark...goodbye.

That said, I don't expect to have that problem here with the heads redone. All things considered, I'm coming out of it pretty good as far as the heads go - $250 for labor to clean them up, surface them (.003" IIRC) and do a 3-angle job on both + $176 in new valves, locks, and retainers at my end = $426 total.

Of course, I'm going to pull the engine and check the bottom end, but I'd rather do the bodywork first. Engine is easy by comparison :rolleyes:

-Kurt
You may want to spring for bronze valve guide inserts. If they knurl the inside of the guides to correct clearances they will be loose in 20 K miles.

My first rebuild of my H code Cleveland was done on a budget. The machine shop Knurled my guides. Granted the work code less than $250

in 1995 money. I rebuilt the engine again in 2002 and went with all new valves (of course) and the bronze guide liners. I had a bigger budget the second time around. 25 K miles later and the guides are still tight.

Ron

 
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Want some h...uh, never mind.

The heads are back from the shop. Alex Parts valves cut and seated to the heads with new locks and retainers. The broken stud was pulled out, cleaned, and a helicoil installed.

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Finally got around to picking the heads up from the shop. Need to pull the block still, but no point in hot tanking it until I've put the body back together (and finished Soylent Green up).

-Kurt

 
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Even though I've decided to part this car out (truth be told, there's hardly anything left on it at this point - I've stripped it quite nicely), an opportunity arose to pull the camshaft and see just how much damage was inflicted on this car by the yahoos who owned it.

This is the worst lifter of the lot. Never mind how much it's been mushroomed - just look at how much of it's lobe (third from front) got wiped off. Yes, that's supposed to be the lobe center!

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Getting the lifter out of the bore required a pair of vise grips on the lifter, but I made sure to do so with the utmost of care so as to prevent scratching the bore. The bore remains perfect.

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Same story for the rest of the lobes; some worse than others:

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-Kurt

 
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Been there Kurt. My engine had 4 "lobes" GONE. To think about all that metal coursing through your main bearings...YIKES.

One other thing, do you have the seatbelt retract stop that goes in the passenger's side interior quarter panel? I only got one of 'em.

 
Been there Kurt. My engine had 4 "lobes" GONE. To think about all that metal coursing through your main bearings...YIKES.

One other thing, do you have the seatbelt retract stop that goes in the passenger's side interior quarter panel? I only got one of 'em.
Another "hot cam swap" by someone who forgot to put assembly lube on the cam and run it at 2,000 RPM, I bet?

If you're referring to the Ginger-colored piece that clips into the quarter, check the box again. One of the stops was clipped in, the other was not, if I recall right.

-Kurt

 

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