nicholas_earl

I just rebuilt my engine and for somereason it turns over really slow. I thought it was the battery so I tried a few other ones and came to the conclusion that its not. It's acting like a piston engine that had its head shaved too many times. I have only hooked the exhaust up, no Intake or nuttin. I also don't know how to set the ignition timing, If anyone can help then please do. O yeah its an 85 12a. it has been ported and such.



Thanks,

Nick

mazdaspeed7

Sounds like a dropped thrust bearing, or possibly an out of spec end clearance.

Lynn E. Hanover

[quote name='nicholas_earl' date='Jul 12 2005, 11:55 AM']I just rebuilt my engine and for somereason it turns over really slow. I thought it was the battery so I tried a few other ones and came to the conclusion that its not. It's acting like a piston engine that had its head shaved too many times. I have only hooked the exhaust up, no Intake or nuttin. I also don't know how to set the ignition timing, If anyone can help then please do. O yeah its an 85 12a. it has been ported and such.



Thanks,

Nick


[/quote]





Take out a plug from each housing and put a wrench on the front pulley. Turn the engine over in the direction of rotation ( top of pulley moving toward drivers side).



The engine should turn over very easily. Trans in neutral of course. This an item you do on the engine stand right after you finish torqing up the case bolts.



If you can see the rear counterweight, it should be centered up between the spark plugs. Thats TDC.



Or, take off the front pulley and see that the keyway is at the 9:00 Oclock position (pointed at the passenger side). That is TDC. If the engine is very stiff or it is locked up. Try loosening the front pulley bolt. If you do that and it turns freely with the bolt lose, you have ruined a thrust washer.



Pull the engine.



You can replace it in the car, but it is easyier on the stand.



With the engine at TDC, point the rotor button at number one leading and drop in the distributor. I will be close enough to fire up and check with a timing light.





Lynn E. Hanover

nicholas_earl

Thanks I will check that as soon as I can. If that is what it is where can I get a replacement at?Thanks again for all the help.



Lata,

Nick

orange

Also, make sure all your earth leads have a positive grounding surface, or put two earths on your engine. It may be that the current from your starter motor is having trouble getting to your chassis.

orange

Another thing, you could check your end float by taking your belts off, taking a firm hold of the main pulley, and try and move it to see if there is any movement. You make have an incorrect sized spacer, especially if they refaced your end plates and used your origanal spacer.