collapsed lifter

[H3RESQ]

Hey there,

New to the forum. I have a 4.7 stroker with about 12,000 miles on it.

I have a collapsed lifter on cylinder 1 exhaust port. Will soon have it complete tore down and know if there is any cam damage. (rocker did move when turning motor over so seems cam may not have went flat)

Its running comp cam 68-231-4 and 822-12 lifters with harland sharp non adjustable rockers. Motor has port/polish, valve job and some other head work done.

This motor was built by Midland engine in North Carolina, however I reside in Washington state (I bought Jeep from east coast with about 3500 miles on the motor) so while I think it has warranty i will have to work on this myself. I started the tear down last night.

Just wanted to jump on here and happily listen to any comments, words of wisdom on the repair and ideas on why I may have had this failure. Wondering what parts are considered reusable and what you guys feel I must replace.
Any ideas or comments towards proper repair are appreciated.


Cheers, Jason

[H3RESQ]

Well got it tore down and its got a flat lobe as well on the cam. So looks like its gonna be time for some work to be done.

I will keep trying to get info on the site without a search engine here. Really wanting to know what may have caused this problem and how to remedy it. I don't really like just putting all the same products back into the motor if it will just fail agian. Is it possible the original owner did not break it in properly? Bad part?

Again, any comments or opinions would be appreciated.

Another comment.. looking at the build guidelines on here it says 4.7 should run a 26lb injector, this motor was built with blue 24's. The top of the pistons have a black "flakey like" carbon buildup. Not sure what to think of the top of the pistons.

[H3RESQ]

Also I have run only Shell 92 octane Vpower since I bought truck along with mobil 1 synthetic oil.

Thanks, Jason

[SilverXJ]

Its hard to tell what happened w/o the cam break in knowledge. Possible bad break in procedure.. maybe valve train binding. Maybe just bad cam. What springs are installed? What oil have you been using?

As for the piston top, its normal to have carbon build up on it. Did you have a wideband o2 sensor installed?

[H3RESQ]

Thanks for response silverxj.

I only have reciepts to go off. I do know that he used the recomended break in oil and purchased it with most other engine parts from summit. (this is were I got my cam and lifter part #'s. Since I got it (3500 miles from build) I have used Mobil 1 sythetic and lucas additive.

The timing cover had some clearance issues, but it looked to have clearanced itself. Not sure if this would be enough drag to cause any issues? Or how to fix the problem on rebuild. (picture below)

Some facts, machine work was paid for 6/12/10 Most parts from summit 2/10 So, I guess while he said it was pro built...final assembly and break in may have been done by p/o
Does this help... Retainer 8 degree 8mm
valve locks 8 degree 8mm
Single spring .400*-.525
jeep L6 billet t/set

My biggest question is if I should just order the same cam and lifters again (and other parts??)? I'm hoping it just wasn't broke in proper. Is this a common issue(specific to cylinder 1)? Seems the build was done as per what is said best on this site. So I'm thinking fluke or bad break in. I'll have a couple very able mechanics helping with the rebuild and will follow the cam break in procedure to a tee when I put it in. So hoping I won't have a repeat in 10k miles.

Catalytic converter failed at 8k. I ended up replacing the whole exhaust header back at that point. I have not replace any 02 since I got it and don't see anything in the reciepts specifically about a 02. Can you tell me more about this?? Also any comments on the current 24lb injectors over going to 26lb ones?

Again, thanks for any help. I appreciate your response and knowledge

Here are a couple pictures of the damged to cam, lifter(youll see the bad one...lol) and timing cover. Pics of pistons too.

[H3RESQ]

Talked with Mike at Midland Engine this morning. He feels failure was due to to little zinc in oil. Lucas additive I was using did not have zinc help for the mobil 1 sythetic i was using.

I'm thinking race oil this time. Have looked on here and seems alot of people run Valvoline VR-1 but seems there is a lot of disagreements on if it actually has enough zinc in it for some of our applications.

What are the bads to running a full on race oil with zinc beyond the fact I'll keep having to replace my cat from time to time?

[herbiehind]

look into amsoil

[H3RESQ]

look into amsoil

Do you have a reason behind this comment? Does it have zinc in it yet not damage the cat? I've been researching a few race oils and zinc additives. My big question still is if there are any down falls to a race oil ran for my application. I street drive my jeep a couple.days a week and drive to most wheeling ( 2 times a month average and a rubicon and Moab trip once a year)

[Cheromaniac]

My biggest question is if I should just order the same cam and lifters again (and other parts??)? I'm hoping it just wasn't broke in proper. Is this a common issue(specific to cylinder 1)? Seems the build was done as per what is said best on this site. So I'm thinking fluke or bad break in. I'll have a couple very able mechanics helping with the rebuild and will follow the cam break in procedure to a tee when I put it in. So hoping I won't have a repeat in 10k miles.

If it was a bad break in, the cam/lifters wouldn't have lasted as long as 10k miles. I'd say you either had a bad lifter or a small piece of debris lodged itself between the lifter and the lifter bore. With the lifter unable to rotate in the bore, the bottom of the lifter became cupped and took out the cam lobe. I had exactly the same thing happen to the no.6 intake cam lobe and lifter in my stroker after 34k miles (Crane 753905 cam), except that I also had a collapsed (but not worn) no.6 exhaust valve lifter, so I put my misfortune down to bad lifters. The Crane cam looked perfect except for that one flattened lobe, and I had been using Mobil 1 0W-40 for all but the first 3000 miles.
I rescued the situation by throwing my spare old stock cam (already seasoned) and spare old stock valve springs back in, so I only needed to buy new lifters and gaskets. Happily 31k miles later all is still well (knock on wood), and I routinely use an SL rated 10W-40 semi-synthetic.

[H3RESQ]

After talking to a couple guys I know that built strokers I am really in belief that the last oil change when I switched to sythetic and lucas killed the motor. It was its first oil without zinc in it.
One of my friends had the same lifter and cam issue (same cylinder even) when the oils were changing and the zinc was being lowered.

We will see how it goes, got parts on order and head is done at machine shop. Pressure test was good and head did not need decked.

He did say he could tell cylinder one vavles got hot, but were not damaged. ?? Maybe friction from failure? Backfiring created heat when valves were not opening due to flat cam?

[dwg86]

I ran Valvoline VR1 in my stroker. It had 18,000 miles on it when it got totaled in an accident. I am running VR1 in my stock 4.0 (2003 Wrangler). It has 69,000 miles on it now, 52,000 when I bought it. According to the tech guys at Valvoline, the VR1 has enough cleaning additives to last for 3,000 oil change intervals, and enough zinc to protect a flat tappet cam. I emailed Valvoline and that was there reply. Most race oils don't have enough cleaning additives, because the oil gets changed often.

[SilverXJ]

Most racing oil needs to be changed at 500 miles or so due to lack of detergents. Two high zinc good oils are Brad Penn and Joe Gibbs Hot Rod oil. Both are for street driven engines with longer change intervals. Both companies make cam break in oil as well. Zinc can damage O2 sensors and cat converters over the long run. But really, how long did cat converters and o2 sensors last in the past? I really don't see that as much of a concern.

[H3RESQ]

Most racing oil needs to be changed at 500 miles or so due to lack of detergents. Two high zinc good oils are Brad Penn and Joe Gibbs Hot Rod oil. Both are for street driven engines with longer change intervals. Both companies make cam break in oil as well. Zinc can damage O2 sensors and cat converters over the long run. But really, how long did cat converters and o2 sensors last in the past? I really don't see that as much of a concern.

Fisrt Cat went out at 8000 miles. So..this cat has about 4k on it so far.

[H3RESQ]

Has anyone had a lifter or cam failure while running Valvoline VR1?

[dwg86]

Looks like a lot of carbon on top of the pistons, and with a cat going bad...burning oil or running rich? What did your plugs look like?