Which starter motor for my car?

[Mattrix]

So I'm finally getting a new starter motor because this one decided to pack it in (it worked every now and then before, now it's just refusing to play ball, so time to replace!).
Basically, I thought they were all the same (some places saying "fits all sbc up until xxxx year") but I'm seeing a few different variations around and want to make sure I get the right one. So, what is going to fit on my engine? It's a 78 model, auto, sbc. There are some good prices on starters on ebay from the states so I will probably end up going down that route. (for example, this one - http://cgi.ebay.com.au/SBC-BBC-CHEVY-HIGH-TORQUE-MINI-STARTER-3HP-RED-/350451381278?pt=Motors_Car_Truck_Parts_Accessories&hash=item519887b41e - provided they don't go nuts on the postage cost!).

Cheers

Matt

[gtc]

Unless you are fussy about originality, high torque (or gear reduction) starters are the way to go. They crank the engine over at around 4 times the speed of the old "low torque" units and get it started quick smart. Less stress on battery, etc. They are also smaller and lighter.

I have a CVR 3.1 HP unit on my solid lifters big block. It was purchased here a few years ago through Rocket Industries, and came with the correct shim set for Chev engines. The old Delco was fond of smashing its pinion gear and damaging the ring gear into the bargain.

I note in that eBay ad that the supplier has had manufacturing quality issues with the SBC BBC brand.

The only issue I've had with the CVR unit is one of the screws on the cap came loose causing the brushes to lose earth contact. Fixed that with Loctite.

I can't comment on small block specs, but in my case I needed to know the number of teeth on the ring gear.

Another thing to consider is proximity to exhaust headers. With the high torque unit's variable rotation mounting angle you may have the benefit of situating the solenoid so that it is away from the heat.

[Mattrix]

Thanks for the response GTC. So, short of counting all the teeth on the flexplate, is there an easier way to figure it out? And no, definitely not fussed about originality, I just wanna get the car starting again so I can drive the damn thing every now and then :)

[gtc]

So, short of counting all the teeth on the flexplate, is there an easier way to figure it out?

I don't know another way, although tooth count is related to the diameter of the flexplate/flywheel so there may be a clue in that for you if you can measure it or find a part number on it. In the end you need to arrive at a total of 153 teeth or 168 teeth.

[Mattrix]

After some serious googling, I came across this -

http://www.chevytalk.org/fusionbb/showtopic.php?tid/171683/

Seems to have the info I need in there. Some good reading, might help some other aussie Vette owners with the same question as me.

[gtc]

You have U2U.

[Mattrix]

So now I just have to work out which one will be best without breaking the budget. I'm still yet to jack up the car and have a look at the bolt pattern (just haven't had a chance, probably will tomorrow though), but the Ecklers site has this one for sale for 1970 - 1981 models  - http://www.ecklers.com/corvette-engine-starter-small-body-for-automatic-transmission-cars-1970-1981.html - which is a staggered design. Have also found this one - http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=190518430342&ssPageName=STRK:MEWAX:IT - and this seller has some others too that are all similar and similar prices. All these starters look the same to me (in terms of quality) so I just can't tell which one I should get (and budget is important, because if it costs too much I'll put it off for too long and the poor car will just sit there!).

[Mattrix]

So I ended up buying this one

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=310309235104&ssPageName=STRK:MEWAX:IT

And I had heard that you could replace old 9 tooth starters with new 11 tooth ones. Well, I bolted it all up, and it is grinding my flywheel horribly. For what reason, God only knows. I had thought that maybe I could pull the 9 tooth gear off the old one and slide it onto the shaft of the new one, however I can't get the new one's solenoid off (some weird, small star shaped heads on the bolts that I don't have a tool for), and there is a bearing preventing the gear from coming off the old one's shaft (can probably work out how to get that off, but am reluctant till I know what the problem is). So, I'm at a loss. And I don't really want to keep working on it till I figure out why it's not spinning the flywheel properly. I would be happy to wait out for an answer but for the fact that at the moment my daily is rooted (smoking beyond repair... crappy old falcon. Have tried everything but can't stop the copious amounts of smoke) and the Vette is the only car I can drive until I sort out a replacement. Daily has been rooted since Sunday, and I can't afford to not have a car on the road as I need it for work... :(

help

[gtc]

Presumably the grinding you are hearing is because the teeth aren't meshing correctly. Reasons could include: pinion gear is the wrong pitch for your ring gear, or the pinion is too far from or too close to the ring gear, or the pinion is overshooting or undershooting the ring gear.

I note that the details for the starter you bought say: 'Drive Plate Size  11" or 168 Tooth', so that's pretty specific as to what it it supposed to fit.

In my experience, bad meshing will likely cause damage to the ring gear and that requires fixing by filing or replacement otherwise you get into a vicious circle of ring gear damaging pinion, and vice versa.

At this stage I would strongly advise getting it to a local Chevy mechanic. Perhaps the Northern region members can suggest somebody.

[Reklaw]

Hi Matt, looks like you're in a spot of bother. Presuming it's the correct starter for your car (staggered design, tooth count etc.) then there's a few other possibilities.
1. There's some conjecture about the quality of some of the products sold by that vendor. Let's hope that there's nothing wrong with the new starter.
2. With some aftermarket starters, they supply you with shims to go between the starter & block. There's some specs about how much clearance you should have between the pinion and flywheel teeth, I forget the measurements, and the shims assist in correctly positioning the teeth. Did you get shims with the starter that you bought? If so, you might have to add shims and improve the mesh by trial & error.

As GTC says, you probably should get the car to someone who knows what there doing.
Unfortunately I don't know of anyone in Newcastle.
Bob

[Mattrix]

Strangely, this one didn't come with shims. Bit ticked off about that fact, because nearly all the other ones on ebay do. I've tried bolting it in with some metal spacers however they aren't doing the job that a shim would, from what I can tell. I'm going to pull it out and see if it meshes up with my old starter. If it does, I'll have to work out a way of shimming it properly. If not, then I have no idea what to do because I obviously won't be able to get my money back :(

[Mattrix]

So, I got it running!
And rather than take it to someone that knows what they're doing, I decided to work it out myself in an effort to becoming one of those someones.
Basically, I worked out that there are 2 main places you can shim a starter motor. You can shim it between the starter and the block, or you can shim it between the bolt heads and the starter. I was shimming it between the starter and the block, and it just never made enough of a difference. As I was pulling the starter off to try something else, I dropped one of my makeshift shims into the bellhousing. So, I pulled the bellhousing off (realising then that I should've done that before I did anything else, right at the start!). Then I put the starter on with the bolts and no shims, and looked at how it sat when positioned normally. It appeared to be ok, so I decided to bolt it up properly and then watch it run with the bellhousing off. What I found was that it was jumping around on the bolts. It turns out that the bolts would be tightly screwed in, but because this starter motor is a bit more shallow than my other one, the starter still had a tiny bit of play. So, I put shims between the bolt heads and the starter motor, and bolted it in. No play, so that was a good start. I then went to start it, and it was misbehaving. I figured it was a battery issue (ran it down too far, trying to start the thing all the time), even though the volt meter said it was ok, I decided I should charge the battery up anyway. So, after charging, dumped it in, turned the key, and it roared to life!
So there you go, something I wouldn't have even thought could be an issue, but now that I've fixed it I feel more educated, ready to tackle the next problem the car throws at me :)

[Reklaw]

Well done Matt. So, in a nutshell, the bolts were too long for that starter, they were "bottoming out" so although they were tight, the starter wasn't being tightened to the block.

[gtc]

Glad you got it sorted. Enjoy the fast starts!