Jeep Strokers

Pulled my engine this week to take the crank out and have it sent back to have the thrust surface repaired. Prior I had some noise from the valve train and a hesitation issue.. After I got it out I found some fine metal in the oil pan and the cam lobes had wear on the nose. I had a magnetic oil plug and I found no metal on that.

This was after I tried to clean up the thrust surface a bit. It ran fine until after that. I don't know what happened. Maybe the lifters got damaged while rotating the engine without oil. Break in was to the T and I used Valvoline VR1 after break in.

There wasn't a whole lot of metal and It was driven maybe a total of 100 miles with the excess valve train noise. I measured the lobes and they all were out of spec, the most having .0069 missing on the nose. Only the nose appear to be damaged, the base circle and ramps appear undamaged. I checked one lifter and it still had its dome. Aside from new lifters, cam, and oil pump what else do I need to do?

When you did this cam set up did you have valve spring installed per the cam specs. I had a long talk with a performance engine builder and with a Tech at Comp Cam about this after my second cam loss. They both feel it is related to to much spring seat pressure and or coil bind. I know a lot is said about Zinc now days and there are a lot of articles about it. The best one I read was in Hot Rod Magazine and was written in part by a GM tech. I now run the ZDDP additive with Zinc and during break in and first few oil changes I ran EOC which is now AC Delco part # 10-421 for flat tappet cams. I am doing another head right now, I sent to Dave Rumping Machine in Gainesville Fl for all the head work porting, spring height, three angle valve job and a good going over for anything else I should do. I am debating on using the Crower Cam savers as a extra measure of caution. If you have not seen these they are lifters with tiny pin hole in the base that lubes the cam constantly. I have never heard anything bad about them but never heard any real feed back on them. The Comp tech told me I do not need them just set the springs right and run their cam break in lube with Zinc. I will post up after the break in and a few thousand miles. Good luck with yours.

Brian E wrote:When you did this cam set up did you have valve spring installed per the cam specs.

I used Mopar Performance springs with seat load of 100#.

I know a lot is said about Zinc now days and there are a lot of articles about it. The best one I read was in Hot Rod Magazine and was written in part by a GM tech. I now run the ZDDP additive with Zinc and during break in and first few oil changes I ran EOC which is now AC Delco part # 10-421 for flat tappet cams.

I am famialr with teh zinc issues and run Valvoline VR1 with a shot of Crane cam lube.

If you have not seen these they are lifters with tiny pin hole in the base that lubes the cam constantly. I have never heard anything bad about them but never heard any real feed back on them.

They don't have a hole on the base. That would be an EDM solid lifter. The camsavers have a flat ground in the side of them from the oil ring down. If you search on here you will find a few posts pertaining to them. I had them at one point. Didn't like them. The finish on the bottom the lifter wasn't that nice and the lifter is constantly spinning, which puts the oil where it actually needs to be only a small amount of the time. Instead I cut a grove in the lifted bore using a lifter bore grooving tool.

So, it wasn't an oil/zinc/break in issue.

I pulled my stroker out of my cj last weekend I've make what i feel was some basic mistakes.044 below the deck and .052 head gasket. I've looked at every thing closely while stripping. I found this am as I pulled the lifters that at the bottom chamfer of the lifter many had a small burr that extended on to the bottom of the lifter that you could feel with my finger nail. I took a hard hand stone and cleaned them up.
These were crane lifters on a crane 905 cam.This motor was never started but the cam was rotated while checking the cam.this cam was bought from summit 4-5 years ago.Assembly lube was still in fine shape on the lifter and cam lobes. I've used crane stuff for many years never did much checking, their stuff used to be first class.

Sounds like you covered every base now it hard to say. I am going to have to look at what you said about the Crower lifters. I assumed they where like the ones they sold years ago when they did the hole in the base instead of the cut out side.

I don't know of any hydraulic lifter that had a hole in the face as that would screw up the internal hydraulics and the prelaod. The only lifters that have a hole on the face are solids. A whole in the face would be ideal, but as I said it can't be done on a hydraulic.

The only reason I can think that mine failed is that the lifters were internally damaged when the engine was cranked over with out oil, and in turn wiped out the lobes. And the lifters still have their dome, which I thought was odd.

i don't think that spinning a motor over that slowly unless you did it constantly. and man do you have the worst stroker luck sorry to here the continued problems. if you ever get to rouch creek give me a call and ill buy ya a beer.

Is something can go wrong, it will go wrong. I think thats my motto.

Which lob on your went? I am doing a study site by site. Mine lost the intake lob #1 cylinder.

your motto or your theme song lately

Brian E wrote:Which lob on your went? I am doing a study site by site. Mine lost the intake lob #1 cylinder.

It seems all the lobes have some amount of wear.

The same thing happened to my stock cam. All the tips of the lobes were worn but the rest looked fine.
http://www.jeepstrokers.com/forum/viewt ... f=15&t=814
It was a stock cam with the original lifters put back in the same order they came out. The only thing that changed was 1.7 rockers. Not sure what caused it either.

Luckily I don't have any other damage aside from the cam. If the pistons were scuffed I think I would explode.

I know I am going to catch a bunch of grief around here for this comment. But I run ZDDP Plus with Valvoline and my reasoning is thats what was in the oil before and you hardly ever heard of cam failures. Now that ZDDP is out of oil and cam failures are on the rise and chatter about oil is a hot topic. But the fact is zinc wearable renewable metal that was put in to help save cams. The new engines are designed to work with out ZDDP but the older engines counted on it.

After my second stoker build I drove my CJ with a 4.7 and 10-1 compression from Los Angles to Chicago the northern route pulling a large U-Haul trailer up through the mountains and as high as 10200 feet above sea level with out so much a a minor hick up. The engine has 6000 miles on it and my vacuum gauge needle looks like its painted on when I am at idle.

Silver it dosent sound like you did anything wrong just go with your gut on what works.

This may be posted on here somewhere else but some of you may enjoy it or learn something. I read this a year ago after my first three cams.




http://www.hotrod.com/techarticles/engi ... index.html