Starter info needed

My 0320 RV4 with catto 3 blade prop, is in need of a new starter. The unit on it now is an automotive conversion and is not up to the task. I was looking at the sky tec in line series and was looking for some input or reviews from people flying with them. Any other recommendations would be greatly appreciated. Thanks
Jim

I’m quite impressed with how the 149-NL cranks my two-blade wood prop on the O-320-B2B (that with an EarthX battery).

Any issue with fit?

I encountered no interference issues. Bolted right up, though I am using an SD-8 rather than a belt driven alternator.

Ditto on IO-320. Had to lengthen the electrical cable; I believe there is a kit with a small extender available out there, to make that easier.

Jim,

As a FWIW, there are thousands of automotive starters turning 320s, 360s, and likely, 540s on homebuilts without any problem. I've been using them on homebuilts since I bought my 1st in 1994.

You might have an issue with your particular starter, or with your particular model of starter. But have you checked everything else in the start circuit for issues? There are a lot of opportunities to have voltage drop in a start circuit, both on the positive and the 'ground' side. And of course, the battery itself is sometimes the culprit, either high internal resistance, or not being fully charged by the charging system.

If you haven't already done the checks, it might save you some money to do them before ordering a starter.

Charlie

This particular unit was never a stellar performer, I did replace the battery. It was older and the resting voltage was below min. After the replacement it still acted the same way. I have checked cables , etc. I would like to be able to use the same type, but I need to have something better than this particular set up. Any suggestions are welcome.

My 1st step would be to check voltage at the starter's 'fat' terminal(s), while cranking. To get valid results, you need the negative probe directly on the battery's negative post (not the terminal; the post). The positive probe should be directly on the starter's positive post. Note the voltage. Move the positive probe to the starter's frame (ground), and test again. Last, move the positive probe to the battery's positive post (not the terminal; the post). Repeat the test and note the voltage.

All voltages below assume that you're using an SLA battery (Odyssey, etc) in good condition. Lithium tech batteries will likely show significantly higher numbers.

The 1st & 3rd test voltages should agree within ~0.5Volts, and should be at least ~8.5--9Volts, up to a max of around 10.5Volts. The 2nd test should read at less than 0.5Volts.

It can be tricky to be sure you've made good contact with both probes, so be sure the probe makes it through any corrosion (which may not be obvious to the naked eye).

If your battery voltage stays around ~8.5-10.5V while cranking, and you see a significant deviation from the other numbers, you may well have higher than normal resistance somewhere in the start circuit. If voltage at the battery terminals stays at or near the 'resting' voltage of the battery, you almost certainly have high resistance in the start circuit.

Hope that's of some use,

Charlie

Thanks. Will try that. I pulled the starter off this pm, and am replacing the ground cable which i think is too small. Will advise.

One last thing; be sure the battery has a full charge, preferably by charging it with a 'smart' charger until the charger tells you it's fully charged. Reason is that if your alternator voltage is somewhat low, *or* you have higher than normal resistance in your charging circuit, the plane may not be fully charging the battery. In the case of high resistance in the charging circuit, it's entirely possible that the a/c's voltmeter could read in the normal range (~14-14.7V), but the battery would see significantly lower charge voltage.

Charlie

Oh yeah, be careful doing those tests!