Cam replacement

Hello everyone replaced the Camshaft an timing in my 78 ford 351M to get some more HP and get rid of the retarded ones. Anyway breakin seemed to go ok but now it has gone bad.:banghead3: So my question is I have looked all over the internet and there are mixed comments. Can I replace the bad one and the lifters and do it again... or do I have to do a total rebuild? Thanks ahead of time

 

What happened? Wipe out a lobe?

 

You need to find out why the cam failed. Lubeing a cam up on installation is critical. I use Moly Disulfide and pour a can of STP over that. There should be no reason to rebuild the entire engine. If metal particles came off the cam, you need to get all them out. Need more info.

 

Yes I think I wiped a lobe, When I put it in I used molly lube as well didnt pour STP over it . Had a hard time getting it started. had to start and stop it a few times. This is the first cam I replaced myself. I guess with all the cranking maybe wiped off the lube. How would I make sure all the metal is out?

 

What are the symptoms that have brought to this conclusion?

 

Sounds like you had the rockers either to tight or loose and it was not opening the valves like it should have, combined with not enough lube will wipe a lobe and lifter right out. Its a good idea to have a buddy bump the starter and adjust the rockers one at a time using a feeler gauge, then fire it when they are close and adjust each while running. Hard starting sounds like the lifters were way off of adjustment.

 

Sorry about that guy, I think we've all been there in one way or another, and if anybody that has done their own mechanical work for a fair amount of time says they haven't there telling you a mis-truth.

I don't think your engine will need rebuilt unless it had no oil pressure, I'd just change the oil and filter and start over.

Did you pre-lube the engine through the distributor hole with a drill on the oil pump shaft and made sure it had oil pressure and oil squirting out of the valvetrain before attempting to start it?
What type oil did you use for break-in?
Timing set manually to TDC on the compression stroke and rotor pointing to the corresponding position on the cap?
What RPM did you hold it at and for how long after it started?
Set the rockers for each cylinder with the valves closed to zero lash?

 

I agree that you shouldn't have to tear into the entire engine but if you wiped more than one lobe you've got quite a bit of metal in there. In the very least pull the oil pan to clean it and the crankcase out and check the oil pump strainer. While the pan's down, glue some thin transmission debris magnets to the bottom for insurance. Years ago I wiped a new cam in my first Grand National after about 10K miles and did just as I explained. It was fine after that.

 

Need more info.

 

Rockers were adjusted way too tight.

 

Went to zero and forgot to back them off?

 

Don't understand why people ask a question, and don't come back!!

If he wiped a lobe, he has powdered metal throughout the motor, and since the drainback goes to the pan, is picked up by the pump, and usually goes through the main and rod bearings first, that metal has been imbedded into the bearings, acting like sandpaper on the crank!!!!!!!!!
Either have a complete overhaul, or get another motor!!!
Even if you 'flush' it, it's on borrowed time!

 

YUP, I have done it and seen it done more then once.

 

Hey thanks everyone for the posts. The symptoms I have are clicking under the Valve covers. Oil pressure went down but the 351M oil pressure sucks any way. The rockers I have on there I did not think they were adjustable. The manual said basicly torque them down. I had to do the whole spin the motor and torque at certian points but other than that.... Well anyway have not had the rocker covers off or drained the oil yet just kind of steped away to regroup. Did some looking on the net and read what some of the symptoms were and well thats how I came to think thats what it was. still Runs pretty strong lots of pep.

 

Things happen! Son had a bad engine in a Craig's list Ford Ranger he bought. Needed the truck right away so bought a rebuilt from a famous Auto Parts store. Lasted less than a week locally. After much hassle he got another rebuilt which has over 20,000 on it now. You just never know.