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YEP!! a nother Crane cam failure!!!

Yeah I know I MIGHT have jumped the Crane cam failure gun,After it cranked with no compression,and then thought about it I went back to my very first "Guess" as to the woodruff key and/or cam gear pin.I did however receive my cam and lifters today.Actually came with a cam report print out :)
Oh believe me I will post pics of problem/reason found.
 
I just went back and read my post, it soudns way more snarky than it was intended to.. sorry.

Its been a stressful week.
 
yeah jeep broken time is always stressful


I spent 9 days putting a hot water heater in my camper. Every time I re-assembled it to fix one leak, another would show up somewhere else. Almost killed it with fire..
 
Hi Mark,

Just did a quick speed read on your thread so I may have misinterpreted some of the information.

Unless you see some of the lobes going away on your camshaft when you pull it out of the engine, I don't think that is the source of your problem.

In your stroker build list it looks like your still utilizing the stock OEM Jeep valves, bet later you mention Chevy beehive springs and retainers.
Double check because the Chevy and Jeep parts aren't interchangeable.
 
I used Crane cams for many year , i.e. special grinds, standards, etc., with no problems. Then a number of years ago, I put one in my 88XJ that had forged custom Venolias with special rings, 11.25 static CR, ported head, balanced assy, SS Chevy valves, etc. At about 10K miles it started running poorly. Pulled the cam and it had worn lobes. Contacted Crane and raised hell and they replaced the cam. I decided the Crane cam quality had gotten bad and never used the replacement cam. Instead, I had Comp Cams regrind a stock Jeep cam for me because the stock Jeep cam lobes are wider than the Crane lobes. Put the Comp regrind in my 88XJ and haven't had one problem after about 100K miles. I don't buy Crane cams any more.

Best regards,

CJR
 
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If you find it to be lobes going away on your camshaft it could be from oil with low phosphorous. Most of the new oil's have lowered phosphorous levels. They are ok with roller cams but will not work with flat tappet cams. They lowered the
phosphorous levels to protect the catalytic converter and lower pollution. With flat tappet cams the phosphorous level should be around above 1100 PPM and some of the new oils it is around 650 PPM.
This may not be your problem but I just wanted to put a bug in your ear. There are a lot of articles on this problem, you may want to check them out.
Good Luck
 
Comp Cams offers a Nitride heat treat option done in house for all of their flat tappet camshafts.

It adds a week and around $150.00, but is money well spent.
 
Comp Cams offers a Nitride heat treat option done in house for all of their flat tappet camshafts..

That is actually the only cam that I have had fail on me.
 
That is actually the only cam that I have had fail on me.

Did you have lobe/lobes go away?

Was it a on the shelf cam?

Did you say a prayer before the first fire up?

:)
 
WEll here is the news...
I pulled the timing cover off and found that the woodruff key had broke and the crank gear was spinning on the crankshaft.I installed a new one when I built the motor.My rendering of what happened was this.I used a rollmaster billet timing set and I do remember that the crank gear slid on pretty easy and checked for any wobble back and forth or rocking where the key sits which was ok.I believe that over time it was wobbling back and forth possibly that caused it to fracture or break.It did wear the crank where it set to the left side of the slot the key sits in.Opposite for the crank gear,wore the right side of the gear.What I ended up doing was to get a new key,jb weld it in place by applying jb and slid the gear off and on the make a good fit,wiping the gear off as I did.Built up a good layer,checking fit and result was a good tight fit..The gear did spin and wore the crank slightly.It did not spin for long,only when the engine shut off and from cranking it.I know that crank replacement was the best option and/or removing it and have it welded and then ground for proper fit,but hey it is a crankshaft that is getting harder and harder to find.A new one was an expensive option from scat.Sooooo on to "redneck" machine repair!!! I cut an aluminium can to fit between the gear and crank to make up for the spinning..I can tell you it was a very good tight fit to get the gear back on.Decent tapping force was needed to get it on not a lot though.Plus I used blue locktite just to make sure it stayed put.As for the gear wearing I ended up using the +2 advance slot which was not harmed it just rounded one side of the zero slot.It was 1 degree of advance on the cam.Put it all back together and ended up needing the dizzy removed and moved one tooth.Started it up and it ran real good.And the lower oil pan noise was gone!!!It must have been rocking back and forth since the noise started at 10k.I ended up getting a sync error code.p1391 I needed to grind the ears off the dizzy and rotated it slightly to align it.Started it up no code and sync was OK on my snap on scanner.I can tell ya this when I drove it with the slight advance on the crane cam...power was even better than it has ever been.I did put a 4.10 rear end in it ,with 235/75-15 tires. when the power loss was evident....acceleration is nutz now!!!
So I did jump the "Bad Crane Cam gun".
Lesson is that when the rollmaster set ,or any other adjustable gear is used ABSOLUTELY make double sure it has NO play at all.Other thought was that the crank had been that way since I got it,not a good fit for the gear .
 
Hi Mark,

Just did a quick speed read on your thread so I may have misinterpreted some of the information.

Unless you see some of the lobes going away on your camshaft when you pull it out of the engine, I don't think that is the source of your problem.

In your stroker build list it looks like your still utilizing the stock OEM Jeep valves, bet later you mention Chevy beehive springs and retainers.
Double check because the Chevy and Jeep parts aren't interchangeable.

The only thing used was the chevy spring.He ground the pocket to fit it.He informed me that the retainer had about 10-15 thousands of an inch "wobble" around the top or the spring.He used the stock jeep retainers.He assured me that it would be fine in a under 5000 rpm motor.He builds hi reving chevy motors.Like I mentioned he was recommended by Roush Yates Egines.
used Valvoline non-synthetic VR-1 since day one.No lack of Zddp then.
 
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Did you have lobe/lobes go away?
Yes.
Was it a on the shelf cam?
It was a 68-231-4. I ordered it from Comp and had them nitrite it.
Did you say a prayer before the first fire up?
Always.

WEll here is the news...
I pulled the timing cover off and found that the woodruff key had broke and the crank gear was spinning on the crankshaft.I installed a new one when I built the motor.My rendering of what happened was this.I used a rollmaster billet timing set and I do remember that the crank gear slid on pretty easy and checked for any wobble back and forth or rocking where the key sits which was ok.
I haven't found a crank cog that does not slip on for the 4.0L. There is no interference fit. The woodruff key does little to keep the gear in place when the engine is operating. What does keep it in place is the clamping force from the harmonic balance.
 
Are you sure you used the correct woodruff key for the crankshaft gear?

The 4.0 uses the same 3/16 x 3/4 key for both the dampener and crank gear.
The 258 crank uses the same 3/16 x 3/4 for the dampener, but has a deeper
and longer keyway slot for the crank gear. It utilizes a 3/16 x 7/8 key.

It's a easy mistake to make.
 
Both the 4.2 and 4.0 utilize the 3/16x3/4 for the cam gear...the longer snout on the 4.2 crank uses the 3/16x7/8 for the balancer.I bought 2 of each 3/16x3/4 and the 7/8 longer one,which is deeper.The 7/8 long one can not fit the crank slot for the gear it would hit the edge of the crank where the bearing is.I checked the installed height of the wood ruff key in relation to the crank gear...
and the back side of the crank gear is tapered where it sits against the crank area in front of the bearing journal.

https://www.dropbox.com/s/s0z5m0pt2r0f00g/2014-11-24 10.37.56.jpg?dl=0
https://www.dropbox.com/s/tevekd3ke0cgzl6/2014-11-24 10.38.38.jpg?dl=0
https://www.dropbox.com/s/u57y3ub61fi7nvq/2014-11-24 10.40.52.jpg?dl=0
https://www.dropbox.com/s/nojptz09iy1u74q/2014-11-24 10.41.29-1.jpg?dl=0
 
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My bad. Your right I got it backwards.
 
I wish the woodruff key was my current issue, but guess I have to swap out cranks:
( Tapatalk will no longer let me upload images unless I upgrade to ios 7 :p).
Anyhow the snout snapped off right inside the timing chain cover :/
The good news is I have a spare 81-86 4-wt crank that needs some polishing, but who wants to tear everything down this time of the year. . .
 
The Rollmaster. It must not have gotten messed up 'cause the engine still runs. The original hb separated at the end of summer and I replaced it with a Dorman(was only one available that day). I also had to replace the crank bolt with a longer one and use washers. The snout cracked off at the end of the threaded(hollow) area, so guess somehow that new bolt was the culprit? I'd show a pic but tapatalk has screwed those that don't update/upgrade.
 
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