Yellow Bullet Forums banner

1 - 19 of 19 Posts

·
Registered
Joined
·
75 Posts
Discussion Starter #1
I have a 540 BBC engine about 14 to 1 compression solid roller motor with a 800 lift cam shaft my question is how hard is it to turn the motor over with a wrench I had starter problems at the track last week and I tried to turn the motor over with a wrench on the harmonic balancer and the motor was very hard to turn over so I pulled the spark plugs and it was still hard to turn over got the car home and change out starter car cranks fine with about 75lb oil pressure and good water temp I also pulled the oil filter and cut it open and no metal in the filter should I be worry about the motor turning over hard
 

·
Registered
Joined
·
1,261 Posts
With an 800 lift cam you probably have some pretty stiff springs on it. I have a 13.5:1 540 with a 800 lift cam and springs 300# seat pressure and it is very hard to turn over with the balancer bolt, even with the plugs removed.
 

·
Registered
Joined
·
1,996 Posts
Install some roller cam bearings and it will roll over a lot easier.
like to see that :rolleyes: 350# on the seat w/ roller bearing :confused: no deal! been there.
its just the nature of have a beast. if you have a flywheel wrench use that, more circumfrence
:partyman:
 

·
Registered
Joined
·
14,490 Posts
Yep ^^^ me too, 55mm cam with 345 on the seat the only thing the roller bearings do is ensure that when you get past a lobe it will smash your hand between the wrench and the alternator or something of that nature.

Seriously it is dangerous to turn a motor over with the plugs out on a naturally aspirated motor, on an overdriven 14/71 its not nearly as bad. But either way I would use a large breaker bar with ratchet head to keep the snap under control.
 

·
Registered
Joined
·
922 Posts
got to be careful, my buddy thought he had made it past the cam lobe, when in fact, he didn't. Almost got knocked out by the breaker bar when it swung back the other way.
 

·
Registered
Joined
·
1,813 Posts
You will never spin it over easily with the plugs in. I turn it a little, let it bleed down and then turn it more.
 

·
Registered
Joined
·
1,365 Posts
What are you using to turn the engine over with? A basic 3/8 ratchet will be hard to turn over with. Use a 1/2 breaker bar thats about 3 feet long. You will have no problem even with plugs in. Problem with turing it over with stiff springs, you will get to a point without plugs that the engine will run away from you and if your not careful, draws blood lol. I don't like to run roller cam bearings in anything unless a babbit bearing isn't available.
 

·
Registered
Joined
·
2,915 Posts
I bought a HD JW flexplate. Ultra PowerMaster Starter. I pull the plugs and use a bump-switch in the engine compartment. NexTek 221448 Orange stripe, triple springs about 380 on the seat. No problems. I tried the breaker bar deal.. no more. If I have to buy a couple starters a year, so be it.
 

·
Registered
Joined
·
1,365 Posts
I use a button also, but I was talking as opposed to a regular open end wrench, aa breaker bar is 100 times easier to turn the engine over with..not a 6" long open end wrench, theres no leverage.
 

·
Registered
Joined
·
13,485 Posts
even with common 300 psi on the seat and 1000 psi open spring presure, the engine should turn with a 3 foot long worn out torque wrench ( 1/2 inch drive).
when one valve is opening, there is another valve spring that is depressing,..so the load on the wrench is just a bunch of bumps in the rotation.


something else may be wrong.
 

·
Registered
Joined
·
296 Posts
I am just saying before I had 55 roller cam bearings installed could hardly roll my motor over with the crank bolt, now it is much easier with same combo.
 

·
Registered
Joined
·
522 Posts
my old ,, last years 555 with 825 cam and 340 on the seat 14.5 comp took 62lbs on the torque wrench to rotate over no plugs more to get started but 62 to keep it moving.. my 522 with a 780 lift cam and thin rings coated brgs and all the tricks took 47 lbs both engines have 7/4 swap cam you need to look at cables grounds and dist lock outs
 

·
Registered
Joined
·
551 Posts
Never tried with something smaller than my 36" custom 1/2" ratchet. .850" Lift with 350+ seat pressure.. Turns over like nothing with it..
 
1 - 19 of 19 Posts
Top