440 cam eating bearings

polyjohn said:

My Compcams story cost me a WHOLE 440ci race engine!

We ordered a upgraded COMP-cam through a known UK dealer and we fitted it, all well and good.
Did the 'break-in' twenty minutes at 2000/3000rpm and the engine started to run rough?

Took the valve covers off and the iron MP rockers were BLUE and melted!!!
The oil was contaminated with debris and the crank/pistons was toasted too.

GUESS WHAT?

No oil feed hole was drilled in the cam for rocker feed???
Not sure how we missed it, but hey we was in a rush to go racing...

Comp cams said 'tuff luck'....NICE, so we sued the UK-retailer...(so sad for them)

It didn't go down well with the Mopar Folks of England...

No we don't use COMP any more even for a PENNY WASHER... (China crisis)

Crower, Lunatti, Isky, MP, we is spoilt for choice lol...

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Comp's fault for sending out a cam with no oil hole.. YOUR fault for installing a cam with no oil hole, and killing an engine, sorry.....

Southern welder said:

LMAO
Y’all are a riot! Arguing is the best part but we’re supposed to think that too mean now, screw that!
Thanks for the information I just got a new set of bearings in the mail I’ll try to pop in and maybe it was the stupid machine shop screwing it up! Or burrs
Can someone with a few minutes please tell me what spec my cam bearing surfaces should be? So I can checks, might just mail the cams half back to have it checked regardless
I appreciate all the helpful advice! And the LOLz of the arguments, I’ll just use an arc gouger to take off the badbit (yes spelled wrong lol) ok ok I’ll stop trying to be an instigator
Thanks all and I might be beck hopefully with ONLY good news

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383 specs are the left column, 440 on the right...

Most big blocks need a little TLC on cam bearings
You have been given enough info to complete an install correctly

33 IMP said:

I have changed cam bearings in engines that were perfectly good, simply because the block was gonna be hot tanked. Im just not gonna do it anymore.
And, i have never owned a 400/426w/440 that NEEDED cam bearings.

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I just refreshed a 400/451 and 440. With new cam bearings. I have never had issue. In fact, this is the first I'm hearing. All cam kits come with bearings. I suppose they could get out of tolerance due to age and abuse. I can also guess. As block is subjected to more stressful cam profiles? That could get bearing bores less true. These blocks are getting old? (If you are talking new aftermarket blocks? Then totally lost?)

Its all about fitment!

What feels right and what don't...
If I see someone beating hell out of a cam bearing installation tool, its wrong.
They just got to be SNUG, not in there forever.
Start at the back and fit one at a time and check it, as you go...

ALWAYS have the block upside down, then any nicks and scratches are on the 'unused' areas.
Tightspots are nearly always around the oil holes and that's the norm.
Don't be scared to take a bearing 'back out' if you ain't happy with it.
The steel support on the bearing 'outer surface' can tell you many things as well as the BABBITT itself.

WHY would you sell a cam without an OIL-HOLE?
Surely its a number one requisite of the cam, to feed oil?

Its funny how you don't look for things, 'that should be there' only things that 'shouldn't be there'...

That stupid hole cost us YEARS of grief and many lost nights of sleep and finances.

You live and learn...

As an aside, a question from the peanut gallery please:
What's the engineering theory behind each bearing being a slightly different diameter?

If they were all the same size, you couldn’t install from front easily. You’d get hung up on the very first bore.

Ok y’all, THANKS
I beat the bearings out, bought a new set, grabbed my whizzy wheel spinner with the long end and put an extended end on it (for her pleasure of course) and massaged the holes, gave the block a 1 1/2 brake clean bath, and IMMEDIATELY ruined the rear bearing cause the tool got shy and slid inside, but got the others in, used some green loctite, it’s for retaining bearings
Got a whole new set of bearings, beat the rear one in like it owed me money and slid the shaft in her slippery holes and she feels so good!
I can spin the cam from the bolt and washer, I’d say it takes 5 ft lbs to spin, put my drill on it and spun for 20 seconds (with the ultra sticky break in install red lube) pulled cam out and no metal on the cam
So the cam is in and crank too
Quickly tho, do y’all just glob in RTV for the rear main seal cap? I got the engine seal kit and I don’t see anything for the sides of the rear main cap
ALSO be careful the clevite main bearings I bought had build up material I recon from when the plated the bearing and I had to scrape the slag off in two spots and polish with some 1000 grit to make it less 3rd worldly

This is the super special retaining loctite, works good, it’s a good trick to have in the tool box

On the last 440 stroker, the cam holes in the block had some surface rust, so I took a small cylinder hone to them to just cleanup the bore, and when doing this, I also put a slight chamfer on the edges so the cam bearing go in without gouging on the edge where the bore is made in the block.
Took my time installing the druabond PDP-17 cam bearings using lighter hammer blows on the cam driver, and the cam fit OK, but not loose. Could easely turn cam with the cam gear on, but not so loose I could spin the cam by finger on the cam end, which is about the same feel after running a slotted cam through the cam bearing bores when the bearings are too tight.
Do check that the bearings fit the cam journals before installing in block. Has a set of different brand cam bearings once, and one of the bearings would not fit over the cam journal un-installed. We double checked with another cam to make sure it was not the cam itself. Wasted way too much time trying to figure out the bearing was problem. Lesson learned.