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View Full Version : Cam failure UPDATE!!!



turbospeed
04-26-2006, 05:12 PM
Well , i just had my engine rebult , and while at it i decided to upgrade the cam , after the shop finished the job i started with problems , difficulty starting it etc etc, then after the first oil change i found a piece of the bolt the retains the cam.

they replaced it , a few miles later the engine shutdowns . and they told me it was the maf..........weird but the car was performing good so i didnt say anything.

last week i was warming up the car a it started idling real bad and some clanking noise i tougth it was the blower , so i removed the SC belt , and it was the same , and then it didnt start.

they towed the car and called me yesterday, told me to get there at 3 , i got there at 2 the cam was in the car , so i asked the mechanic the problem ; the problem was the cam , because it was a solid cam and i had rollers ; but i pointed to him that the cam wasnt properly aligned , he told me because maybe it was the wrong cam too ; at this point i started to get suspicious , and asked him if the cam could be installed in some wrong , and for some reason he was too eager to show me the problem once the cam was OUT of the engine , he told me no........

so after that i went to a race shop and described the problem he told me the cam wasnt installed rigth........

anyways here are the pics.

XxSlowpokexX
04-26-2006, 05:21 PM
well dam a broken lifter...That would do something...If the car did run fine I doubt they installed the cam improperly..However maybe they didnt tighten something properly..Stock SC cam?

turbospeed
04-26-2006, 05:26 PM
actually 4 or 5 of them are broken

the cam is a CM stage 1 clone

XR7 Dave
04-26-2006, 05:42 PM
then after the first oil change i found a piece of the bolt the retains the cam.

There is your answer right there. The cam bolt was not installed correctly and it backed out allowing the cam to move laterally in it's bore. When it does this the lifters smack the next lobe and break. You should be able to see evidence of this on the cam also.

I am 99.9% certain it is the right cam, I had it ground by Comp Cams and it is a core that came out of a Supercoupe. The grind # is etched into the end of the cam if you want to check that. Regardless, an old school 3.8 flat tappet cam will not physically work in these motors as far as I know.

If the numbers are all rubbed off the end of the cam, then look at the cam plug at the back of the motor for damage. There should be no sign of contact back there but I'm guessing in this case you'll probably see evidence of contact and rubbing from the end of the cam.

The situation sucks, but you have an issue with your mechanic. :(

Randy N Connie
04-27-2006, 09:02 AM
I would measure and inspect the lifter bores
before putting it back together.

Randy

S_Mazza
04-27-2006, 10:43 AM
Maybe the issue was in the bolt itself. Stuff can break due to unseen cracks, etc. Of course, it would have been smart for the mechanic to use a new bolt, but ...

turbospeed
04-28-2006, 12:36 PM
well yesterday i had a huge discussion , with my mechanic about that he told me he wasnt paying a dime............

well this morning he went to my house and told me he was sorry; he lost control ; and he agreed to buy a new cam , (but the machine shop told me mine was still good , just needed a polish) , pay for the lifters and everything , , well the guy at the race shop told me i should really replace the oil pump, what do you think.

if you could make a list of thing that should be replaced due to the metal shavings running it will be great.

thanks in advance

XxSlowpokexX
04-28-2006, 02:48 PM
Theoretically we dont know what went where. Be nice to see a bearing or two but i doubt teh engine is comming out. It was pretty cool that your mechanic offered to pay. Not many would. If it wasnt a new pump you may want to get one. Pull the gears out..If they look fine put em back.

If teh cam is ok get it polished. No sence getting a new one unless you want something different...Ande good luck

XR7 Dave
04-28-2006, 02:48 PM
Pull the oil pump and look for any scoring in the housing and check for smooth and free spinning of the gears. If they are stiff or sticky or if there is scoring on the rotors then replace it. Look at the timing cover also. If the cover is scored badly then find one that isn't scored as bad. It doesn't have to be perfect but you don't want it to be bad.

If you replace the oil pump also replace the relief valve and spring in the timing cover. Also flush out the oil cooler if you find any debris of any kind in anything. I'd pull some bearing caps also and look for bearing scoring. Basically inspect things thoroughly.

Lifters aren't that expensive (about $7.50 ea) so other than some gaskets and few misc things it shouldn't cost that much to fix. The cam bolt is supposed to have locktight on it. Be sure to torque it to specs. ;)

Randy N Connie
04-28-2006, 06:46 PM
I would all most bet my life that the cam is no longer straight.
I would get this check out.Chuck it up and check with dial indicator.

If it is bent slightly,It can be straighten by using a blunt air-chisle.
By vibrateing the apposing side. it will only take a burst of .5 to
one second.Then recheck straightness..

This is done by a cam grinder I know to true up his cams.

Good luck Randy

turbospeed
04-28-2006, 07:58 PM
well im taking the cam to crower cams tomorrow for inspecting , if they say its better to replace it i will , dave would you happen to have a suggestion for a cam :D

mine is the .493 one , something a lil more agressive....:D i will replace the springs if needed , the only headwork i have is 3 angle valve job.

XR7 Dave
04-29-2006, 03:41 AM
well im taking the cam to crower cams tomorrow for inspecting , if they say its better to replace it i will , dave would you happen to have a suggestion for a cam :D

mine is the .493 one , something a lil more agressive....:D i will replace the springs if needed , the only headwork i have is 3 angle valve job.

Email me if you end up needing one. I have a couple ideas for you if you need it.