engine won't turn over

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David Trower
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engine won't turn over

#1 Post by David Trower »

I removed an SC engine from my A coupe, put in an A engine.
The engine will barely turn over. It is as though the battery was very low, which it is not
There was no problem starting the the SC engine when it was in the A.
I changed the starter bushing some time ago.
Any ideas on why the A engine will now not turn over properly?
Thank you
David

Dave Erickson
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Re: engine won't turn over

#2 Post by Dave Erickson »

What is the history of the A engine? I.e. what do you know about it. Did you bench run it prior to installation? When did it last run? Try squirting some oil in the spark plug holes and crank it without ignition and see if it frees up.

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Martin Benade
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Re: engine won't turn over

#3 Post by Martin Benade »

I’d check the ground connections at the transmission and battery end as well as the battery positive terminal.
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Dave Erickson
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Re: engine won't turn over

#4 Post by Dave Erickson »

Also, turn the engine over by hand, with a 36mm socket on the pulley bolt. You should be able to feel the resistance and compare it to the SC.

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John Clarke
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Re: engine won't turn over

#5 Post by John Clarke »

Absolutely Dave.
You wouldn't install an unknown engine! It must be a connection failing . And something was disturbed on installation. 30mm Dave on the Pulley Bolt 36mm Genny Nut
😁 Jay
 

David Trower
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Re: engine won't turn over

#6 Post by David Trower »

I know the engine to be good. What could have gone wrong on instillation? Could the starter bushing have been knocked out? Would incorrectly wired cause a problem? All suggestions greatly appreciated.

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Martin Benade
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Re: engine won't turn over

#7 Post by Martin Benade »

The wiring should be undisturbed along with the bushing. If the ignition timing got advanced accidentally that could slow it down, try cranking it with the coil disconnected.
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George Hussey
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Re: engine won't turn over

#8 Post by George Hussey »

make sure that the ground strap to body is cleanly connected. remove the plugs and make sure that the engine turns over very freely by hand. Check the battery connections.
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Wes Bender
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Re: engine won't turn over

#9 Post by Wes Bender »

As Dave E. asks in his post #2 above, when was it last run? Depending upon storage conditions and length of time, it may not be as easy to turn over as you might have expected. If you find all of your ground connections are good, I would pull the plugs and squirt some oil in the cylinders and turn it over by hand to see if it gets easier. I wouldn't expect bearings to be a problem, but piston ring / cylinder bore friction would be a different matter. If it wasn't "pickled" when stored, rust could be an issue.
Some days it's just not worth chewing through the restraints.....

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Mike Wilson
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Re: engine won't turn over

#10 Post by Mike Wilson »

+1, Wes.

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Jim Liberty
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Re: engine won't turn over

#11 Post by Jim Liberty »

+2 Wes. ......Jim.
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Harlan Halsey
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Re: engine won't turn over

#12 Post by Harlan Halsey »

David,
A problem is not enough information from you at the start. You state that slow cranking is the problem. So, did you try turning the engine over with the generator pulley nut wrench as we do to adjust the valves? Did you pull the plugs and see if it turned over like gangbusters? If the engine is not free with the pulley wrench the problem is internal drag. Most likely lightly rusted rings, since you say the engine is "good". If the engine is free by hand, but not with the starter, plugs out, the problem is with the ring gear, pinion interface. It is barely possible that the clutch adjustment differs a lot between the two engines, does the TO bearing have play? Your first objective should be to localize the problem, only then to address it.

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Re: engine won't turn over

#13 Post by David Trower »

What is the recommended procedure for putting in and removing the engine with regards to the muffler?
Should the muffler be on or off? Which is easiest?

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George Hussey
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Re: engine won't turn over

#14 Post by George Hussey »

the muffler can come out with the engine, but take the rear sheet metal off and of course the S pipes
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Wes Bender
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Re: engine won't turn over

#15 Post by Wes Bender »

Either works and I've done it both ways. My current choice is to remove the muffler because the engine balances better on the dolly I use. I also remove the carbs. They clear just fine, but if something were to slip unexpectedly, they are an expensive item to replace.
Some days it's just not worth chewing through the restraints.....

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