How hard should a rebuilt motor be to turn?
 

Hello, I have rebuilt a 1.8 motor with 9.0:1 supertech pistons and ACL bearings. As I have been building the motor I would turn it by the crank bolt and and a 1/2" ratchet. It always seemed to easy to turn, however, once I installed the motor and transmission into the car won't turn over easily.

I removed and tested the starter, it checked out fine. The motor turns easily until it I hit about 270 degrees, then it becomes hard to turn. I removed the spark plugs to see if it made it any easier, no difference.

Today, I removed the transmission to looks for signs of metal on metal contact. I haven't seen any, but I am tired and its dark. I will do a closer inspection tomorrow in the daylight. But I was able to turn the motor by hand a little easier. I can turn the transmission input shaft by hand easily.

My question is how much resistance should there be in turning the motor by hand? Also, is there anything that can obstruct the flywheel from turning once the transmission is attatched?

Thank you in advance.

valve problem?
piston to valve contact?

should turn over fine. mine had zero issue being turned with a small ratchet

Sparkplugs in or out?

Dann

Timing belt too tight? The 1/2" ratchet was fully assembled motor on the engine stand?
Stock valve train?
Hydraulic lifter weirdness?
So the motor went in, and then the starter was used to prime the oil pump and pressurize the system?
Sorry, just more questions.

Should turn over easily by hand without the plugs. Accessories such as P/S, alternator, etc. should only add minimal resistance.

Sounds to me like you have some interference in the transmission to engine. Either installed crooked, so it binds, or the flywheel is rubbing.

Are you in neutral?

Do you people even read the original post before you ask these questions? How can you expect to give any assistance at all whatsoever with his problem if you can't even read. Yeah, bet he want to take your advice or suggestions. :bang:

To the OP, why did you start with the starter? What happened when you tried to turn the motor over with the key? It just seemed so spin slow, or was their any noise?

Sounds like interference somewhere in the clutch, flywheel, starter area. Then again, it's kind of hard to know the way you talk about the motor turning over. At this point now that you have the sparkplugs pulled and the transmission down you said the motor turns easier, but almost sounds like you are still concerned with how it turns.

With no plugs, no tranny, and no belts, you should probably be able to turn it with a 3/8" ratchet, so a 1/2" ratchet should be with only a little resistance twice in the rotation as you reach TDC and push the compression out the sparkplug hole.

No plugs, no compression. You should be able to turn it with no resistance at all, except for the valve springs. If not, the engine is messed up.

When I tried to start the car, there was a metal scraping/grinding sound coming from the starter/bellhousing area. My original idea was that the starter wasn't aligned or the transmission could be misaligned.

"Are you in neutral?"

I attempted to start the car in neutral and with the clutched pressed in. I had the same result in both cases.

"Timing belt too tight? The 1/2" ratchet was fully assembled motor on the engine stand?
Stock valve train?
Hydraulic lifter weirdness?
So the motor went in, and then the starter was used to prime the oil pump and pressurize the system?
Sorry, just more questions."

Not sure how the timing belt could be on too tight, I thought the belt tensioner was spring actuated. The 1/2" ratchet was on the engine stand initially. I made sure the motor was easy to turn after added any major assembly piece during the build, ie: pistons, head, timing belt.
Yes, stock valve train.
Not sure what you mean by hydraulic lifter weirdness, I disassembled the HLA's, cleaned them and put them back together in the same spot they came out of.
I wasn't aware of needing to prime the oil pump, used Lucas engine assembly lube on everything during the build.

Its almost warm enough for me to go back under the car, thank you for your suggestions and I'll updated the thread as I find out more.

Something misaligned with the flywheel is my first guess.

if it turns over by hand out of the car, and the trans turns over, and you heard that sound, then its fairly obvious to me that the starter may have been the culprit.

Unless you dropped something in there I do not see how anything else might interfere with the flywheel

I inspected the bellhousing area, no metal shavings or signs of metal on metal contact. I going to start taking off the accessory belts and check the timing belt.

https://www.miataturbo.net/attachmen...ine=1389567540

https://www.miataturbo.net/attachmen...ine=1389567540

This is the point at which the motor becomes difficult to turn. After the timing marks hit the 12 o'clock position, the motor turns with little to no resistance.

https://www.miataturbo.net/attachmen...ine=1389567540

Just to be clear . . . you have now taken the tranny and starter back off and it is still difficult to turn over?

The engine is basically back to the way it was on the stand, only it's installed in the car, yet it has now become difficult to turn EVEN WITH THE STARTER AND TRANNY NOW OUT OF THE EQUATION?

If that is the case, then something is messed up in the motor or perhaps a socket/wrench/bolt/etc. fell down into the timing belt area and became entangled with the belt/pulleys when you tilted the motor reinstalling it? :dunno: WAG

With the starter and transmission out the motor, it was still hard to turn, but only once. After that, I couldn't replicate the problem. I am stumped(not that I'm a very experience mechanic anyway.)

The timing belt is aligned properly. I loosened and re-tightened the tensioner pulley just in case. I will start to put the car back together this week little by little after work.

Thank you for all your input. I will still post here, hopefully it will start this time.

I dropped a small socket down between the crank pulley and timing belt without noticing it one time. The motor turned over fine until it pinched the socket between the belt and pulley and completely stopped. That's probably not the issue, but it might be worth checking to see if something found it's way down there.

How many ft/lbs did you torque your pressure plate bolts too

How did crankshaft look when you took it out. I rebuilt small block Chevy that had a scar that I didn't catch and bearing would grab on that journal and made it hard to turn over.

It definitely sounds like you need to break the motor down and find the problem. With the starter and trans out of the equation you know the resistance you last felt was from the engine side of things. I would start with accessories and see if they turn freely. Water pumps go bad all the time so I would try ti find the problem with PS/AC/WP, then remove timing belt covers. If you do not identify the problem then I would break the engine down completely and start over. I like to take lots of pictures to both document what I did for potential resale and so I can look at my pictures and see that I did use assembly lube on every bearing surface, every connecting rod has TWO nuts, main caps, yada yada yada....

PLEASE find it, and make sure you tell us what the problem was so we can all learn from this.

Did you disable your clutch switch? you could have killed the thrust bearings on initial startup and now its hard to turn.

Oem flywheel bolts? If they're too long they'll lock up the motor. And that's something that wouldn't show itself on the stand.

Nice idea and, at this point, that actually sounds like one of the "best case" scenarios too.

Brilliant thinking Curly! I have seen this first hand.....and didn't think of it! Props to you Sir....

It's only because I just pulled my flywheel off and noticed mine are blind, which explains my "RMS" leak.

Curly, please forgive my ignorance, but what did you mean by "blind" ?

Excuse me, I meant through hole.

https://www.miataturbo.net/attachmen...ine=1390053379

Through on the left, blind on the right.

Can you imagine the naming conventions if thing were named nowdays?

No blind holes, no slave drives, no bastard files.

I have used the factory flywheel bolts. The strange thing is, I can't replicate the problem anymore. I have installed the transmission, and drove the car for a short bit. I had an oil leak coming from the oil pump pressure relief bolt. Which lead me to this thread: https://www.miataturbo.net/engine-pe...ht-pics-58278/

https://www.miataturbo.net/attachmen...ine=1393826602

https://www.miataturbo.net/attachmen...ine=1393826602

I took it out and used a thread sealant and put it back on. Now I have a small leak from the front of the oil pan. I suspect the front main seal. But I am also now throwing a CEL, the car is idling a little rough and it randomly struggles to start. I suspect I'm off by a tooth on my timing belt. I will double check both next weekend. Does this look like it is properly lined up?

https://www.miataturbo.net/attachmen...ine=1393826602

your cams are timed relative to one another.

No idea on timing relative to the crankshaft though.

Hm, it should be TDC, but I'll double check it tonight. I think I may off on my timing belt based on this thread: http://forum.miata.net/vb/showthread.php?t=227838

Cams look good, it's always hard to tell unless you take two pictures, straight on the cam marks of each one. Kind of like trying to read the speedo from the passenger seat.

Is this a little better:
https://www.miataturbo.net/attachmen...ine=1393906315
https://www.miataturbo.net/attachmen...ine=1393906315

I know its hard to see, but this is the current position of the timing sprocket. I haven't had time to remove the accessory belts and timing belt cover. I'm temporarily working two jobs.

https://www.miataturbo.net/attachmen...ine=1393906315

I found this thread when I was looking up CEL codes:

http://forum.miata.net/vb/showthread.php?t=227838

This is why I suspected the timing belt being off. I will double check the CEL code as soon as I get a chance.

looks PDG to me

So have confirmed my oil leak is coming from my front crank seal. I used a flyin miata front crank seal install tool and it pressed the crank seal further in by about 5mm. My question is, should I replace it or try using it again? The front seal is few months old and has about 15 miles of use. I also plan on using the cam seal installing tool to double check the cam seals.

https://www.miataturbo.net/attachmen...ine=1394244570

https://www.miataturbo.net/attachmen...ine=1394244570

https://www.miataturbo.net/attachmen...ine=1394244570

I also had a chicken that would not leave my garage, no idea why.

https://www.miataturbo.net/attachmen...ine=1394244570

I "believe" you're only supposed to have 19 belt teeth between the marker lines on the camshaft pulleys - from mentally superimposing the images on top of each other, it looks like you've got 20 teeth between the marker lines.

Nah, I looks right if you count from either side's cam marker to the middle of the FM tool; 10 teeth including the dead center one from either side, which adds up to 19 (since you don't count the center one twice).


Umm . .. chicks dig miatas ? :dunno:

I had better luck with a Felpro gasket. You can also tighten the inside spring a little.

Well, I put everything back together. The cam seals are not leaking. But the front crank seal is puking oil. Is there a brand I should buy for the front main seal? Or should I buy an oem one? I used the seals that came with my upper gasket kit.

If you happened to score the crank when removing the old gasket, you won't get a decent seal with anything. As a habit, I only use OEM seals, but it seems most people who've had leaks found it was caused by either a nick on the seal surface (crank) or an over/under depth placement of the seal.