Flat cams...still a problem??

[lawrence]

I posted this on the cal-look forum, so I thought I would post it here as well.

It seems like the issue of a flat cam is not such a hot topic as it was a few years ago. Is it still a current problem that plagues our hobby and flat tappet users in general? I am asking this because I may or may not have a flat cam. I purchased a Webcam 86b and lifters from Webcam in 2005 when the majority of bad attention was pretty much aimed at Engle.

I still have to do more investigating on my car to determine whether or not the cam is the problem. I was reading old posts and some said the their car seemed to run much smoother right before the cam went flat. My engine has run pretty smooth since I built it, so Im not sure how I would notice this.

I am asking anyone who had a cam problem what they noticed, saw or heard from their engine when their cam went flat. Thanks for the help and I will keep the forum posted on what I find.
 

[deano]

For example.... I shot a new off-road car last month, with a T-4 engine. Lifter died within the first 15 minutes on the road.... after being broken in  on the dyno ... Still happening, and even with the pros.

[Jim Ratto]

I posted this on the cal-look forum, so I thought I would post it here as well.

It seems like the issue of a flat cam is not such a hot topic as it was a few years ago. Is it still a current problem that plagues our hobby and flat tappet users in general? I am asking this because I may or may not have a flat cam. I purchased a Webcam 86b and lifters from Webcam in 2005 when the majority of bad attention was pretty much aimed at Engle.

I still have to do more investigating on my car to determine whether or not the cam is the problem. I was reading old posts and some said the their car seemed to run much smoother right before the cam went flat. My engine has run pretty smooth since I built it, so Im not sure how I would notice this.

I am asking anyone who had a cam problem what they noticed, saw or heard from their engine when their cam went flat. Thanks for the help and I will keep the forum posted on what I find.
 

Hi lawrence. When my car ate the Berg cam I had in it id didn't run any smoother. It ran like crap, and it was unlike any other problem I had worked out before (i.e. intake leak, plugged jet, bad plug, etc...). It couldn't be tuned out. This all started when I drove my 2276 Super Flow about 300 miles one summer night.... by the time I got to my destination the tune was gone. Next few days the problems just got worse. Soon the motor sounded real weird over 3000rpm and it was straining. One more try at tuning it... then I noticed two leading carb stacks were foaming over with fuel spray when I revved it. Why only front two barrels? What was only thing that would make two carbs 30" apart do the same thing only in front barrels?
# 1 & 3 exhaust lobe was gone.
Do you have an oil filter you can inspect? If not get a Canton-Mecca filter, run it and take it apart and go thru it with a strong magnet. You'll know right away if your cam is gone.

[lawrence]

Hi lawrence. When my car ate the Berg cam I had in it id didn't run any smoother. It ran like crap, and it was unlike any other problem I had worked out before (i.e. intake leak, plugged jet, bad plug, etc...). It couldn't be tuned out. This all started when I drove my 2276 Super Flow about 300 miles one summer night.... by the time I got to my destination the tune was gone. Next few days the problems just got worse. Soon the motor sounded real weird over 3000rpm and it was straining.

Damn Jim, this sounds WAY to familiar. The engine was running great after I got those new idle holders, so I was driving the car more. Then one day the "tune" went away. Checked a lot of different things and saw nothing different than before. Still have a few things to check out and am keeping my fingers crossed.

Thanks for the replies. Anyone else?

[Sarge]

Wouldn't your valves suddenly be way out of adjustment if the cam was going flat?  I like having the old Berg cow magnet clamped to the oil pick up for debris in the oil.

[Jim Ratto]

  I like having the old Berg cow magnet clamped to the oil pick up for debris in the oil.

amen!

lawrence I forgot to say that I pulled v/c's off when all this was unfolding and man the aluminum rocker chambers were like a pearl dark grey... not silver.

[Donny B.]

The valve adjustment doesn't change that much because the wear is mostly on the nose of the cam and you adjust on the heal of the cam.  Mine got caught early, but I still had to replace both the cam and he lifters.

[John Rayburn]

When you pull the valve covers, you can just run your finger across things, and in the valve cover, and you'll see the pearly grey stuff as mentioned earlier. Also, the engine can have kind of a dull, rotary metalic sound. Not obvious, but you can usually make it out if you stand to the side or front of the car away from the exhaust. Good luck!

[lawrence]

So here is what I have checked so far:

Did an oil change and valve adjustment yesterday and the oil did not look any different to me. Did not notice any pearly stuff in the rocker boxes and the valve clearance was within tolerance. I DID notice quite a bit of fuzz on the berg cow magnet that I keep on the pickup tube.

I opened my inline fuel filter with sintered bronze element and there was some junk in there. I cleaned it out.

Timing is set to 10 degrees BTDC. All ignition stuff is connected correctly and the grounds are clean. Plugs look good, no corrosion in the distributor or cap.

Removed both sets of jet stacks from the carbs and blew through them with compressed air. All squiters are delivering a nice stream when the linkage is depressed.

Pulled the 3&4 cylinder rocker cover and my dad rotated the engine while I watched to make sure the rockers are moving the same distance. Everything looked good, but I do not know how accurate this test is. I should try and set up some dial indicator.

I dont know what else to check really. The car has never run this bad before and it is very sudden.

[John Rayburn]

It would be good to check lift with a dial indicator, assuming you knew what your actual lift was before the problems, then compare.

[lawrence]

Well the cam is NOT flat. This car is either cursed or has a mind of its own. I reluctantly fired it up tonight after the timing check, jet cleaning and rocker movement test. It instantly idled and ran like it should. Took it for a drive and it ran hard! I stopped off at a big parking lot to mess with the mixture screws and before I touched anything it started to idle kind of crappy again. Gave it a few clean revs and I made it back home without another hiccup.
 
I am thinking that the 60 idle holders are too small and I had a plugged jet. Does anyone on this forum who is going to sacramento bugorama have jet drills. I will probably have my friends LM2 with me and try to get this thing dialed in.