Tight Crankshaft [engine reassembly]

[Falkon]

After a few hours of reading directions, searching for lost parts that are right behind me and triple checking everything i could think of, I finally got the basics of the lower half of the engine put together. This includes; pistons, rods, crank and cam shaft, all new bearings etc.

As soon as all of this was done i tried to turn the crankshaft and noticed that it was not the easiest thing to do. You can barley turn it by hand. I did manage to turn it over a few times just to make sure nothing was grinding but even after re-lubricating the bearings its still very stiff. The Pistons fit nicely so i don't think its those. But obviously I don't know the really reason why it is doing this so that why iv come to ask the experts.


All other engine reassembly questions i have i will also post here.

 

[smaceng]

I'm sure the experts will chime in here, but it is a matter of elimination. Did you check any of the rotating items prior to connecting them up? One should always take baby steps in assembling an engine. Crank first, then check if it rotates OK, then one piston and rod at a time. Then assemble the cam, check it for rotation. Then add the timing chain/gears. So, to find out what is tight, do all the steps, but in the reverse order. If you find out that one item is too tight, and it was not an assembly problem, then it is best to take it to the machine shop and let them fix it.
Good luck,
Scott in CA

 

[racingenglishcars]

The largest source of friction by far is new tight rings sliding in newly honed cylinders.

Now is the time to degree your camshaft!

 

[Gerard]

For this reason, it's a good idea to check your tolerances with Plasti-gauge first to make sure the crank bearing were finished to the right tolerance. I always check both rods and mains. You don't say if your bearing are STD or oversize. If you think it's unreasonably stiff, bolt up just the mains and see how it feels. You should be able to turn it by hand and it should feel smooth throughout the rotation.

How does it feel if you put in the pulley nut and turn it with a moderate length breaker bar?

 

[jlaird]

I would bet that it is just fine. New rings against newly refinished cylinder walls creates a bit of friction. Being able to turn it over by hand sounds just about right to me.

 

[Falkon]

I did put new bearings in and they are all standard. The cylinders have been honed to .02 and i have put in new pistons and rings that are .02. As i disconnected each rod and piston one by one the crankshaft did become easier to turn. And if you put a 1 ft breaker bar on it you can turn it with just your pinky finger.

 

[Roger]

Just a thought - did you gap the rigs correctly?

 

[Gerard]

I did put new bearings in and they are all standard. The cylinders have been honed to .02 and i have put in new pistons and rings that are .02. As i disconnected each rod and piston one by one the crankshaft did become easier to turn. And if you put a 1 ft breaker bar on it you can turn it with just your pinky finger.

Sounds like you're good...

 

[recordsj]

did you match all the bearing caps to its mate?

 

[Falkon]

Just a thought - did you gap the rigs correctly?

No we did not. I didn't know that you had to gap rings. I pulled one piston out and it definitely needs the rings gaped. They are practically touching.

Now knowing that I have to gap the rings. What would be the proper way to gap them without the professional ring gaping tool.

 

[Trevor Jessie]

Just out of curiosity, what brand rings are those?

 

[Falkon]

I ordered them from NorthWest Import Parts. The Box that the piston and ring set came in was from Sakura Pistons.

 

[jlaird]

I must say those rings are too large and need cut down a bit.

take em to your friendly engine builder for cutting. Bigger gap is better than smaller.

 

[Trevor Jessie]

You can get a reasonable ring filer for $30. I wouldn't try to do them free hand.

 

[regularman]

How much gap have you got? I usually give the pistons and rings to the guy that bores the holes and let him do all that checking. I don't know how everyone else does it.

 

[Deleted member 8987]

In the old days, nobody gapped rings.....and often you had to tow the car with a rope to get it lit the first time.
The ring ends look like they're touching.
Too Tight!

 

[regularman]

In the old days, nobody gapped rings.....and often you had to tow the car with a rope to get it lit the first time.
The ring ends look like they're touching.
Too Tight!

Yeah, that is what I was thinking. As long as he has some gap it might be ok. Its a water cooled car engine. I have played with a lot of air cooled motorcycle engines and they are not so forgiving. Everything swells quite a bit on them and so the guy that bores the jugs gets everything so there is ample gap when the aluminum pistons swell and everything. They usually mark it each piston for each hole so that they can figure for any differences from spec on anything.

 

[Falkon]

I found a video tutorial on how to gap the rings by Moss. I'm thinking that's how I'm going to do it. All i need is the feeler gauge which i cant seem to find any where.

Also, there seems to be a bit of surface rust showing up on the cylinder walls. I can still wipe it off with my fingers but knowing that it was rust that originally caused the engine to seize, how exactly can i stop it from continuing until i have the head completed and done.

nychIcU" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"> </embed></object>

 

[Deleted member 8987]

Oil. You squirt oil on the walls (I just use 30WT, but probably use what you're gonna use in the engine), wipe it down......and soak the ring grooves behind the rings.
Make a mess.
Rust means unprotected metal,,,,,it won't be as susceptible once it's burnished by running, but right now, maike it oily.

 

[Deleted member 8987]

Hang on....is this your first engine rebuild? You DO know to "stagger" the ring gaps? You know for sure which side is "up"?
Just checking.
Dave