Datsun Roadster Forum-311s.org

Trying to start the rebuilt U20 and having a tough time spinning the motor. Have tried raising the front end to soak the seal for some time and even with a jump it spins about 2 revs and craps out. Tried starting fluid but think the engine can’t spin up enough to even put out a decent spark to ignite. Even loosened up fan belt off water pump and Alt. Tried pulling plugs and spinning motor which of course does better. So, does a gear reduction starter offer quite a bit more torque? I may have to try that route if I can’t get it going here. The battery is in great condition SGravity good and charged. Can anyone offer other suggestions that I may exhaust before buying a Gear Redux starter? Thanks, I want to make Solvang!

The rope seal should not have enough friction to stall your starter unless it is dragging already. Have you checked and double checked your timing? Try having someone turn the key while you move the distributor.

The crank spun easily with mains torqued, it’s after the new rope seal was installed I noticed it was somewhat tighter. Much researching on the net reflected that most usually the starter would overcome this. It just may be that my starter is tired. Maybe 1-2 turns and battery may go down to about 9.5 Volts during a 10 sec start. Engine will turn manually with wrench on crank bolt but it takes some effort. If only the engine would start up on first crank.

Yes a gear reduction starter will go a long way for you. I've misdiagnosed an unhappy starter for a tired battery. I bought a new battery and again would only get 2 maybe 3 revolutions before no go. If the car didn't start in 3 revotions or less, it wasn't going to start.

I would guess its not an overly tight engine, but that could also be a factor. I'd look at the starter first.

Will

Tom, I am in the midst of a garage refurb, so won't be going to Solvang and roadster has been out on the driveway for quite a bit.
If you want to take my starter and try it out to see if it is yours, I can pull it and hand it off to you. Then if it makes it better you can get a new one and give me the old one back.

nismou20 wrote: ↑Fri Mar 29, 2019 2:37 pm Maybe 1-2 turns and battery may go down to about 9.5 Volts during a 10 sec start. Engine will turn manually with wrench on crank bolt but it takes some effort. If only the engine would start up on first crank.

My thinking is that a weak / low, battery cranking capacity is not helping. I could be wrong, but I don't think a healthy 12 V (12.6 volts, fully charged) car battery should drop to as that low (9.5 volts) after cranking for only 10 sec. You might try a better battery, with or without, jumper cables, before replacing the starter....YMMV
Mike

So with 60” overbore I really don’t see it has increased CR that much although my bore/bearing clearances are tighter. I jumped the car with an identical battery but not much more significant oomph. It just may be as simple as a worn starter. Interstate 640cca.

Tom,
I have a DB electrical gear reduction starter, works great. Pretty good company, I would recommend this one as noted in Tech Wiki:
https://www.ebay.com/itm/New-Starter-fo ... Sw43haExeI
http://www.311s.org/pmwiki-311/pmwiki.p ... iftStarter

Linda

Hi Linda, Would you happen to know if this one is the short or long Nose? Price is right!

nismou20 wrote: ↑Fri Mar 29, 2019 2:37 pm The crank spun easily with mains torqued, it’s after the new rope seal was installed I noticed it was somewhat tighter. Much researching on the net reflected that most usually the starter would overcome this. It just may be that my starter is tired. Maybe 1-2 turns and battery may go down to about 9.5 Volts during a 10 sec start. Engine will turn manually with wrench on crank bolt but it takes some effort. If only the engine would start up on first crank.

The drag to overcome should be no less than 10 lbs and no more than 25 lbs.

Tom,
It is the exact number as in the Parts Interchange page, it is a 9 tooth gear reduction starter for the H20 forklift. I think it is short in that it fits nicely but you can email for exact dimensions. Here’s a link from the install....
viewtopic.php?f=2&t=18124&p=246889&hili ... al#p246889

Linda

Thanks Linda,

nismou20 wrote: ↑Fri Mar 29, 2019 4:56 pm So with 60” overbore I really don’t see it has increased CR that much although my bore/bearing clearances are tighter. I jumped the car with an identical battery but not much more significant oomph. It just may be as simple as a worn starter. Interstate 640cca.

You have the same bore as I do, your compression ratio went up, over 10:1, likely closer to 10.25:1. (That is what I calculated mine at.)

My little Odyssey PC680 (210CCA) will crank my gear reduction starter over with no problem. I can crank it for a good minute solid with no slowing.

Will

Still good battery ground connection with the engine after reinstalling?

Yes, Added one from starter mount bolt to frame as I never had one. The other ground points to frame and engine are there. Will go forward and purchase a Gear redux Starter and see. If that fails I will probably have to pull the rear main bearing and try to flatten the lower rope seal.