I think I have a major problem brewing...

barishiman

Well-known member
Hey guys, here's my dilemma. I'm no engine guru, but I know the basics to an extent. My engine is still on the engine stand with the head attached. I went to the harmonic balancer to move the pistons and cam a few turns. It was very rough and not like that every before when I went to turn it. I have been oiling the cam in the past without the head... but now I have the head on. I poured some oil down to the lifters and did a few cranks, but it's still that same rough turn. I don't know what to do. I'm lost and I my shop manual doesn't have anything on it... and I still haven't got my Falcon Performance Handbook.

What do I do?

The only thing I can even think of is putting the push rods and rocker arms back on and do some turns to push the lifters down... Gosh and everything was going so well on the rebuild.. :bang: :bang: :bang: :bang: :bang: :bang: :bang:
 
8)

It will normally be harder to turn it with the valvetrain and head installed. It will be even harder once you put spark plugs in since you will have to fight compression
 
A fresh engine is going to be very hard to turn with no valve train if you have the plugs in. Every piston is going to be on compression on the way up.

With the rockers in, it'll be hard to turn as each piston in turn comes up on compression. You should not feel any grinding or grating, however, so make sure the "roughness" you feel is just the normal cycling of pisotn events.
 
Maybe a stupid question, but is your timing chain installed? If not, you may be hitting your cam with one of the pistons. Trust me, I speak from experience on that one.

Also, check your stand and make sure you don't have something binding on the stand. (Also speaking from experience).

Slade
 
I didn't even think about compression plus I do have the spark plugs installed. Maybe that would explain the sound of air escaping from the engine. The timing chain is installed because I never took the cover off and didn't want to fool with it. I feel so stupid. jezzz... :oops:

Andrew
 
Well I guess it seems ok now barish, the good thing is, it doesnt seem to be the problem my brother had, he honed out one of his blox once and after puttin stuff in, he tried to turn it and he noticed it was real rough and eventually it got to where he couldnt turn it, and crazy as he is, while trying to turn it w\ the help of a hammer :: whinces ::
he broke his damper and guess what it turnt out to be, it was dirt in the piston ring grooves, yep, he dint clean the grooves out, so he was able to get the pistons out, take out rings, clean the grooves, put it all back together and it turnt right on around....
 
Twenty years ago I learned the hard way on my first OHC Datsun rebuild to make sure that the crank and cam are at TDC before setting the head in place. I tourqed down the head, then rotated the crank to align the timing marks. Felt two slight bumps while turning the crank. Finished assembling the engine, then before installing the plugs I rotated the crank with my finger over the plug holes. No compression :? Yup, had to pull the head back off and replace two valves :oops: I lign up the timing marks on ALL engines now, just so I don't forget on the ones that really do matter.
Lazy JW
 
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