Cranking after rebuild

[JPP]

I tore the engine down, B2B 1/2 ton 218, hone the cylinders and replaced the rings, got it all back together and it is hard cranking. I have oil flowing, correct timing, I just feel that cranking so slow won't build up necessary compression to get the fuel into the chamber to fire. I do get an occasion pop from a cylinder firing but nothing continuous. Help!! Oh it is a 6volt system.

[Dave72dt]

Start with the basics if it is turning over slowly.  6 volt starters tend to do that anyway compared to 12 v systems and the modern gear reduction starters common on todays cars, trucks.  Check condition of the cables, size of the cables and grounds. Common 4 gauge cables are not adequate. 1/0 or larger preferred.  Are the cables or starter getting hot?

 

Fresh rebuilds also tend to turn over a bit slower.  Recheck your static timing.  Slow turning with correct timing and proper air/fuel ratio will still start.

[JPP]

Dave, I think cables are poor, will upgrade and retry. Thanks

[greg g]

Cranking speed has little to do with compression and starting. Please remember you are only a couple years removed from an engine that still had a hand crank fitting on the crankshaft pulley. Did you do a static timing procedure to set a baseline setting for ignition timing? Are you sure you have the rotor aligned with the proper spark plug wire for #1, and that the rest are in proper firing order?

[NiftyFifty]

Couple years removed? My truck still has the nut on the front to crank it by hand, his 50 should as well....but I don't recommend trying it Sounds to me like timing issue, "pops" usually indicate bad timing, and if too far advanced it will cause slower crank

[Jeff Balazs]

I had my starter rebuilt by a local shop last fall. Made a world of difference to have this done right. First time around with another shop it was never this good.

Having a 6 volt system doesn't have to mean slow starts. With a good battery and charging system and the right size (2/0) cables you shouldn't have any trouble turning it over. When you have it all correct it will start just a quickly as a modern vehicle. I drive mine daily and it always starts right up.......hot or cold.

 

Jeff

[Charlie Stephenson]

Try using a hand held pump oil can and squirt 3 full strokes of the oil can into each cylinder, turn it over without the plugs, replace the plugs and start er up.  I hope this is your problem solution.