I realized early this morning that I had the whole day to myself (and only 1 ale)

The Valaint!....I could actually work on my car without guilt or interuption.....quelle rapture!

Turns out the crank is prolly ok....rod bearings are toast....cam is toast...lifters are toast(chipped edges).....and the oil pump drive gear is toast(we already knew that)

The question is why.

Everything looks groovy EXCEPT the Hughes timing set crank gear appears (even to my unbespectacled eyes) to sit a tetch too far forward compared to the cam gear (which appears to sit correctly when pressed to the block in correct thrust position).

Wild speculation might conclude that this would "pull" the cam forward....leading to oil pump drive gear failure.

I dont have a cam button.

Other than the insanity of having only 1 ale on a day off....does this make any sense?

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Yeah....Im the one who destroyed this rare, vintage automobile.....

Put a cam button in there ya silly Canuck. They are actually almost free ya know.

IIRC, the one I lost had a cam button.

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Official Cookie and Mater Tormentor.

Well, would a person not need to find out exactly where the cam needs to ride before just sticking a button in. I mean we need the chain to run straight to begin with, or it will wear, or even break. But the cam has its own needs (lifter & oil gear alignment). Ofcourse when that possition is found then the button needs to hold it in place.


It sounds like the Hughs gear set is not a exact match to what is needed. Or maybe the thrust on the block for the cam gear is worn. Or maybe there is just this much difference in machining between each block, or cams that something out of the ordinary will need to be done. With the way you described the fitting of the gears, it almost sounds like there was suppose to be a Torrington Bearing that went behind the cam gear for that set. Even if not, with some creative machining it would be a good way to get it all lined up. But everything will have to start with the cam possition, and be fitted off of it. And yea, in the end when all is lined up, a button to keep it there.

I really think that these kinda problems is the biggest thing that causes oil gear failure. Then you take missalignment & add heavy oil, or a high volume oil pump & it gets worse.



Jess

The cam is in the correct position when the cam gear is against the thrust pad on the block (38000 mile BH block).

No sign of cam gear/timing cover interference.

Half the lifters showed signs of edge chipping.

Crank end play is in spec (just perceptible)

A Torrinton bearing behind the gear would make the misalignment permanent.

A stock oil pump with over 100000 miles was used....other than the gear it is in perfect shape.

I use 10/30 0il in everything.

Mebbe I can machine the crank gear down to a better spec?

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Yeah....Im the one who destroyed this rare, vintage automobile.....

Oh man, somebody airlift Sandy some ale, with only one beer on a day off I'd be out of alignment and trashing my oil pump gear.

Sounds like we still aren't any closer to solving that mystery of 'what the heck causes this to happen...' but...

I'm thinking that the cam button is a necessary step forward for insurance on any build (or may partially eliminate one stress on gear failure...making gear mesh/ improperly machined/hobbed gears the next one...). Maybe timing set selection is not as good as one would think either.

Sorry to hear that the whole thing is toast...


-D.Idiot

Can I use a cam button for a BB Mopar?

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Yeah....Im the one who destroyed this rare, vintage automobile.....

Make your own Button.
I have a special punch that gives me a correct location.

Drill & weld a nut onto the cover and use a rocker arm adjust ball screw... done.
DD

Conversation with Hughes tech:

He suggests "shimming" the cam gear till it matches the crank gear.

Not too far from Lucky 13s suggestion....except he suggested a bearing is a waste of money (dont like wasting money)

Shimming starts to sound like a good path toward other problems.

I could machine down the crank gear....that will cost more than the timing set cost to begin with.....

Should I just go back to the slant pile and add my best stock timing set?

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Yeah....Im the one who destroyed this rare, vintage automobile.....

I used a stock $20 replacement link-belt timing set in my 64 Dart for 40-50k miles with my big cam and strong valve springs. It was getting stretched when replaced, but worked fine. I would have no qualms about using a stocker in the motor you have. Giving up 1-2 HP sounds OK, eh?

Seems like you oughtta get your $$ back from Hughes... The cam gear must be machined wrong?? They should be using a BB Chrysler chain and crank gear.

Lou

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Home of Slant6-powered fun machines since 1988

Well.....lets see how the gears line up with a split duration 280/270 109 lca 2adv Erson cam behind them,,,,,be here next week.

I think I spend some time figgering whether the cam or the crank gear is out of spec. ( yes the crank gear is dot side out)

Polish the crank......new bearings.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

There was some noise about the cam oiling holes not lining up on someone's Erson recently? Should check that on assembly and grind as needed.

Should be a nice cam for your combo.

Lou

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Home of Slant6-powered fun machines since 1988

Got started on a cam button front cover today....ready to drill and weld.

Checked 3 stock cams (65-76) and they are all identical.(excluding profile)

The Comp 264 had the oiling holes drilled 180 from the stockers...

The Comp 264 had a much narrower drive gear. Where the stockers had a nice radius at the sides the Comp was narrow and abrupt. The gears on the Comp were worn and broken,,,,the two high mileage stockers gears looked the same as the 37000 mile one.

I checked 1 Hughes timing set (roller)
1 Comp timing set (roller)
1 Steel cam gear OEM link
1 nylon/alum OEM set link

The Hughes and Comp are identical
All the cam gears placed the cam in the same location.

The Comp and Hughes crank gear seem to pull the cam gear ahead.....notso with the OEM sets.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

I have had v-8 sets where the crank gear was thinner and I had to shim between it and the balancer, but the teeth on both gears and chain all lined up.

I cannot imagine it being ok to have the cam farther in or out than the factory placed it. Sure there is some tolerance there, but not much. Even if you can shim an aftermarket set so the cam is set right, will the gears align properly for the chain?

I can see the cam being off causing all kinds of problems, including the oiling holes not lining up well front to rear.

Is it possible that the lower gear is on backwards, even if they put the timing marks on the wrong side of it? That does not solve the cam location, but might keep it from pulling the cam forward.

A button is cheap insurance and always a good idea. There are really no downsides to using one. I would stick with a solid type on a street engine, either metal or nylon. A torrington is not really needed but could be a real problem if it falls apart on a high mileage engine.

This is kind of my worry, this next engine I just installed, I wish I had time to take pics of, the stocker chain with the cam I could pull the cam gear away from the block 1/4" by hand, once I used the Rollmaster set, it was very tight (it would walk about 1/16" if you used a big screwdriver)...
So amen to the cam button... it's good to see what else people are observiong, I have a couple of OEM cams to look at next time I order an aftermarket cam for 'comparo'.


-D.Idiot

Mine walks .035 with no screw driver....

I am tempted to dump the faux double roller sets and go with the cheap/dumb/easy nylon gear set that doesn t pull at all....

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Yeah....Im the one who destroyed this rare, vintage automobile.....