Rebuilt Engine Is Hard to Turn Over

[transformer]

Just installed a rebuilt 911SC engine which was done according to Wayne's book.

I installed the original starter and tired to build up the oil pressure, but the starter barely turns the motor over. I tired a new starter and its turns over a little better. The battery is good and I have a charger on it.

I have replace the clutch, resurfaced the flywheel, and the engine turned over easily when I adjusted the valves.

I have checked the ground strap on the transmission and the starter connections.

Could someone Help.

[cgarr]

Could there be a lot of oil in the cylinders from the rebuild? Can you try it with the plugs removed?

[kwikt 911]

Did the rebuild include new main bearings? If so, was it alignbored also?

Kevin

[ChrisBennet]

Originally Posted by kwikt 911

Did the rebuild include new main bearings? If so, was it alignbored also?

Kevin

If it turned over easily when he adjusted the valves I don't think it would be bearing friction. I think it is rare that an SC case needs align boring - I think most people would just get another case. SC cases are pretty stable (unlike a 2.7 mag case).

I'd check the voltage at the starter and I'd measure the resistance of the battery to starter cable. Look at the cables that attach to the battery. Sometimes some of the wires attached to the battery clamps are hanging on by a thread.

I assume you don't have the fuel pump relay installed but just in case you "tested" the fuel pump earlier by lifting the metering plate I'd check to make sure the cylinders aren't full of fuel.

Then I'd do a sanity check of the timing by using a leakdown tester to make sure the valves were closed when they are supposed to be and open when they are supposed to be.

-Chris

[jomama]

you need to load test your batt. any auto store can perform this test for you.i had pulled my hair out thinking the batt hooked to charger would make the batt good not the case.hope this helps

[Tall02]

I would suggest you pull the plugs and see if the engine turns over easy. Make sure the fuel relay is pulled.

Do you encounter any dragging sound like the flywheel or clutch are interfering with anything?

As noted before make sure you have a good ground and a good hotwire connection to the starter. A weak connection can look like a bad battery. You may have voltage but it is the current that makes the difference to allow a quick rotation.

Good luck