1st Start-Cant turn over

[gregg hake]

Trying to start my engine after a complete rebuild and I find it wont turn over completely. Does anyone have any suggestions as to what I have messed up ??
Here are the main points.
1. With starter out of the bell housing, solenoid and starter work normally.
2. Installing the starter, it inserts into the bushing very smoothly. Bushing was not replaced.
3. When I turn the key, the starter engages and the engine turns about 1/5 of a turn...then stops, as if the engine is too tight to turn.
4. I engage the ignition again and the engine again turns 1/5 of a turn and drags to a stop...etc.
5. When the engine stops turning, it isn't stopping like it is hitting a barrier, it drags to a stop although in a very short time span.
6. Battery is a new Optima with full charge.
7. Voltage is over 6 volts at the starter (new wiring).
8. Putting a wrench on the belt pulley, engine turns as normal. It has always seemed tight to me, but this is my first rebuild so I have nothing to compare it to. There is no sensation of grinding or odd sensations.
9. Starter was just checked out by a well regarded electrics tech and he feels it has very little wear.
10. This is a 62 Super with big bore kit (NPR). 6 volt electrics.

[Ron LaDow]

Gregg,
Nice presentation of what you've found and, in effect, eliminated. Thanks. You've got a AArrump, AArrump. AArrump...?
Pretty sure you are in a hot-bed of 356 wizards; I'd ask for local assistance.
Added by edit: Check your ignition timing and plug wiring.

[John Brooks]

Will it spin by hand with the plugs removed?

[gregg hake]

Hi... I will remove the plugs tomorrow night after work and give it a spin ! How easy should the motor turn spin with plugs out? Should I be able to spin it effortlessly or will it take some effort?

Thank you.
Gregg

[Vic Skirmants]

Effortlessly. How about that starter bushing?

[David Jones]

I am with Vic on this. I once tried 4 starter motors before changing the bushing that I was certain was OK. Suffice to say it was not. I had to concede that I was wrong after the 4th starter that I took out of one of my other cars that worked perfectly but not in the suspect car.

[ralph bauer]

Nothing to add, only to compliment Ron, John, Vic, and David for their excellent input.
Gregg, with their kind of advice and experience I'm sure your problem will soon be history.

[gregg hake]

Minor update.
After my long commute tonight I had a little time to remove the spark plugs. Then I turned the key, the starter engaged and the motor spins freely.
Tomorrow night after work, I will put the plugs in again and see if the motor still turns !
I put in an oil pressure gauge (Harbor Freight kit) in so I could see how much I had when I finally got the engine running...it says 15 lbs while I turned it tonight. Is that typical with a "no spark plug" beta spin?
Also, I have a new bushing ordered so that will go in as soon as it gets here.

I appreciate all the input and ideas.

[David Jones]

15 psi is OK for a spin on the starter. Now you mention the big bore kit, did you check that none of the plugs are hitting the pistons and are the pistons and heads compatible as in both are 30 degree angles or both are 22.
Was the starter a Porsche or VW unit. The VW starters are less hp though not much, 0.5 as opposed to the Porsche 0.6 hp but on a newly rebuilt engine with the increased drag of new rings it could drag the starter down quickly especially if all the heavy battery connections of both pos+ and neg- placements are not scrupulously clean, a resistance will quickly build as they get hot and slow the transfer of power to the starter motor. If you are comfortable with oil pressure and from what you say I would be, you could if you live where you find it acceptable get someone to tow you around the block and drop the clutch in second gear and get it started that way. Back a long time ago when I was sometimes unable to afford both the rebuild of an engine and a new battery that was the acceptable alternative.

[Neil Bardsley]

Somewhat off topic but to get rid of vapour lock rather than removing the spark plugs and turning the engine over. Mr Staggs, on the 912 forum, said he turns the engine in anti clockwise to clear out the fuel/vapour. If it works for Jack it's good for me

[David Jones]

That would be hydraulic lock Neil. Vapour lock would be fuel line or pump.

[gregg hake]

Hi All

Regarding Davids comments...
1. "Now you mention the big bore kit, did you check that none of the plugs are hitting the pistons and are the pistons and heads compatible as in both are 30 degree angles or both are 22."
I inspected the plugs last night and there was no sign of anything hitting the ground electrode. The big bore kit was the same NPR kit that was on the car when I purchased it in 1990 (ish). The engine ran pretty well for a few years after I purchased the car and many people told me to expect the pistons and cylinders to be out of spec but the local rebuilder/machine shop (well respected and trusted in the Pacific Northwest) measured them when he did my other machining and said they were "perfect" so I re-used them.

2. "Was the starter a Porsche or VW unit?"
I assume it is a Porsche starter. I purchased it from the Porsche dealer as a Bosch Remanufactured starter 20 years ago and it sat in the box until I installed the engine this year. Are there some distinguishing marks on them to help me verify this?

BTW...the reason for the timeline gap between disassembly of the car and my current reassembly is "Life gets in the way". Between the unexpected divorce and raising the kids, paying for college, etc... there is a 20 year gap in there where not a lot got done.

Thanks for the input, guys.

Gregg

[David Jones]

Greg, this may help on starter ID. The forum is a great resource especially doing a search on it.
https://porsche356registry.org/article/198
I assume that new piston rings were installed and until they bed in that is where the most resistance to engine rotation is generated.

[gregg hake]

Hi...looking at some pictures of the starter I took a couple weeks ago, there is a sticker on it saying it is a Bosch Remanufactured and it is an SR21X. I believe I have a real 356 starter !

Bosch.jpg (731.9 KiB) Viewed 1278 times

[Greg Scallon]

Hey Gregg,
Could your valves be mis-adjusted such that you have full compression on multiple cylinders at the same time. Too much for the starter to overcome?
-Greg