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Main Crank Pulley bolt

P

pugetsounder

Advanced Contributor
VP AQ120B OHC is the main crank pulley bolt standard thread or reverse?

Any good suggestions on how to get this bolt out? Any tricks on holding/seizing the engine? Not sure I have enough room for an impact wrench. Thanks.

It looks like I have bad oil seal, not leaking too bad but just started squealing like a pig. I isolated the squeal down to the crank pulley. Now it's a matter accessing the oil cover and replacing it. It's always something...
 
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Ayuh,.... To lock up a motor, pull a spark plug, roll that cylinder up to near Tdc, 'n insert a length of rope, turn the motor, 'n tighten the rope against the head,...
 
Thanks guys. I've heard of putting a socket/breaker bar on the bolt with the breaker handle against a stringer and clicking the starter. I was just trying to figure if that would loosen or tighten therefore snapping something off. The engine turns clockwise while facing it so holding the bolt in place should loosen, right?
 
The knot wrench works!

Seriously, a properly sized rope, and with the piston at approximately 30+ degrees BTDC, could never be compressed enough to cause a greater force than normal combustion would create!
Once the bolt has been loosened, back the piston off and remove the rope from the cylinder.

.
 
RicardoMarine said:
The knot wrench works!

Seriously, a properly sized rope, and with the piston at approximately 30+ degrees BTDC, could never be compressed enough to cause a greater force than normal combustion would create!
Once the bolt has been loosened, back the piston off and remove the rope from the cylinder.

.
Click to expand...

i understand the process, but when designers were designing a light, perfectly balanced system, I would hazard to guess that the tiny bearings, wrist pins, knuckles and valves were not designed to be subject to the torque of a 200lb+ impact driver or 500-1000lb force breaker bar level to remove a no doubt rusted crank bolt. Before handing out costly advice without a warning, maybe you should also agree that a crank holder, a tool specifically designed for this job, is the best way... lol
 
Ever tried to start an engine without a starter motor? "Normal combustion" as you describe it, is actually pretty weak, that's why it needs 3000rpm for us to be able to go anywhere using it... ;p
 
@ Britishbrick
If you had a problem doing it this way you did something wrong period.
This method has worked an immeasurable amount of times. It is used at car repair shops, boat repair shops, small engine repair shops.
I would suggest you should not make your first 2 posts chastising a very well respected and knowledgeable member when you should be reading and learning.
Just my opinion. Have a nice day
 
PatinIdaho said:
@ Britishbrick
If you had a problem doing it this way you did something wrong period.
This method has worked an immeasurable amount of times. It is used at car repair shops, boat repair shops, small engine repair shops.
I would suggest you should not make your first 2 posts chastising a very well respected and knowledgeable member when you should be reading and learning.
Just my opinion. Have a nice day
Click to expand...

I never said that the method wouldn't work, I've done it myself in a pinch. BUT when giving advice that could damage someone else's engine, I like to add the caveat of also including the "proper" way to do things...

no one was being chastised. lol
 
PatinIdaho said:
@ Britishbrick
If you had a problem doing it this way you did something wrong period.
This method has worked an immeasurable amount of times. It is used at car repair shops, boat repair shops, small engine repair shops.
I would suggest you should not make your first 2 posts chastising a very well respected and knowledgeable member when you should be reading and learning.
Just my opinion. Have a nice day
Click to expand...

Pat, I would agree with you.

I'm not feeling chastised at all!
I have been doing mechanical work since the earlier 60's, and began working as a mechanic by the late 60s.
I have always followed protocol unless an alternate method has proven to work well and safely.

Service manuals are written in a way to aid average Joe mechanic and to ensure that Joe's work is most effective.
Average Joe may not have the mechanical aptitude as does Bob, but we want to suggest safe procedures for both Joe and Bob!

If a rope is used to hold the piston stationary, the torque required to either tighten or loosen the front bolt is reduced by the leverage advantage created by the crank throw (I.E., 1/2 of the stroke dimension)
Cylinder compression pressure is no where near that of combustion pressure...... especially @ LPCP!

IOW, if applying let's say 75 ft lb torque against the head of this bolt, I believe that you'd be hard pressed to create enough force (through a soft rope) to damage anything above it!

That having been said, sure........ if you own the correct size strap wrench, try it first.

I can tell you first hand that the rope idea is nothing new, nor has it been warned against to my knowledge.




.
 
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