Re: What next? Starter?

Posted by HH56 On 2014/10/5 11:35:05

Depending on how or where valves were stuck, you could still move the engine by hand.

I would do a compression test if you did not see a noticeable difference in speed with and without plugs. With plugs and good sealing valves, the engine would be having to move the pistons in a compression stroke. There would be a load on the starter slowing it down as the piston moves up and compresses the fuel mixture. Without plugs there is no compression so starter can spin engine considerably faster as the mixture air is just pushed in and out the hole. If some of the valves are stuck and even slightly open the mixture air will move in the manifold the same as if the plugs were out so there would again be no load on the starter.

If you don't have tools or are able to do that test another thing would be to pull the valve covers off and check the valves visually. They should all be able to move as you crank the engine. If you can see any springs that do not appear to be moving up and down at all or at least the same amount as another then it would require farther checking.

The battery should not be going flat after 10 seconds so I would really wonder about the capacity or the condition. Is it a new battery and if so, what is the CCA rating at 32 degrees? An 8 needs a fair amount of capacity so if it is much less than 700 it could be too small to crank the engine at speed. On the bigger engines most are getting batteries capable of at least 750 CCA and sometimes more for the really big engines.