hey i have a 89 f150 302 i am rebuilding the engine i am having issues with the cam and bearings now i am on my third set of bearings, 2 cam, and 2 engine block. the last bearing keeps belling out during install and the cam had to be tapped in with a hammer and take a lot of force to spin. i have tired taking the last bearing out and putting the cam in and still the same thing even without the last bearing in the motor. dont know whats wrong i know the auto store sells .010 under bearings don't know what that all about but i bought standard size bearing any advice would help

 

Sounds like you need to get a micrometer to mic the cam and bearings so you know what to get

 

ok i will try that tomorrow my brother has a digital one do you know what the standard size is

 

What cam are you installing?

Sounds like something isn't right. You said even without the last cam bearing in, the cam doesn't want slide in.

 

stock cam slides in till last bearing that why i thought to remove the last bearing and same thing wont slide in, i can hit the cam with a hammer and it will go in but takes a lot of force to spin. i miced the cam and reading 2.081 on the front cant find what the standard size is

 

Ok now you need a internal micrometer to measure the inside of that rear cam bearing. Sounds like the rear cam journal needs to be machined.

 

if it were the rear journal why would it still do with out the rear bearing and the cam not even touching the block in the rear and thats why i got the second block thinking maybe i warped the first one

 

It almost sounds like the cam is warped. Check the cam on a flat table, the rear portion might be the issue.

 

2 cams same thing

 

you may need to get the block align honed/bored down the cam journals. or find a new block....if you can confirm that the bearings are correct for your cam, and your cam is true (sounds like it is good and staright, as new cam didn't fix problem), then unfortunately it sounds like something funky happened to the block.


has it ever overheated? starved of oil?


hmmm...I reread that you've tried two blocks and two cams.


are you sure youre installing the cam correctly? its not just going to slide into the last bearing without lifting the entire cam by the front snout....

 

thats what i thought since my motor did over heat but i got a second block and same exact thing does any one know the standard diameter of the front cam journal

 

I don't off the top of my head, but any engine builder should be able to tell you the specs of not only standard diameters, as well as the bearing clearances. A lil time on google should work too. Something could certainly be awry there too. Need to define what you have, and confirm they're supposed to work togrther.

And you've installed cams successfully before? If there's a hammer in your hand, you're doing it wrong...not trying to patronize.

 

Here's from the Haynes manual: Camshaft Bearing journal diameter: 302

No.1.....2.0805 to 2.0815 inches
No.2.....2.0655 to 2.0665 inches
No.3.....2.0505 to 2.0515 inches
No.4.....2.0355 to 2.0365 inches
No.5.....2.0205 to 2.0215 inches

 

thanks ill mic the all of the cam when i get the micrometer back and this is my first cam but my brother even tried and he' has done many cams all from stock engines to 900 hp big blocks without ever having an issue and he cant get it either