nate99

This is actually on a 428 Pontiac in my Trans Am, so it might be different from what happens on BBC/SBC's, but you guys are pretty sharp with engines, so I figure it wouldn't hurt to ask here in addition to the more sparsely traveled Pontiac board I am on.

I am trying to fix a starter issue, and despite getting a type of mini-starter that I could shim away from the flexplate, I still do not have enough clearance between the dsiengaged starter gear teeth and the flexplate gear teeth.

I did notice that the gear ring on the flexplate is offset a bit more toward the front of the car off of the main disk that bolts to the crank.

Is it possible that whoever assembled the engine/transmission put it on backwards? Two different brands of mini-starter hit the flexplate gear teeth, and the snout of the stock one that I took off is notched to clear the flexplate gear teeth.

If it can not be flipped, it may be that the flexplate itself is just way out of tolerance.

This can't be normal, and I am getting frustrated.

Thanks

Aldo_45030

i think it is or i should say on a AMC304 it is. the heads of the bolts hit when turned because of the dish of the fly wheel.

jnb5101

the "bumps" where it bolts to the converter on the plate should bulge out toward the converter.

Richard Cooper

nate99

I don't really see any bulges around the bolts on either side. The contour of the flexplate curves around the coutour of the torque converter, i.e. they are both concave/convex in the same orientation.

Here is a pic.

jnb5101

your picture isn't very informative, but there should only be contact between the plate and the converter at the bolt sites. it can't be flat, one side has to be raised at the bolt hole areas.

nate99

I understand, perhaps I'm doing a poor job of describing it. Here's a shot of the converter side of the flexplate.



I suppose what I meant was, there is no "bulge" in the flexplate near the converter bolt holes.

With the dish of the plate, I don't think you could get it attached to the converter if it were flipped.

This is a longshot idea, just casting around for opinions.

Thanks.

'75

That last pic looks like a balance weight welded to the flex-plate, I'm guessing it's backwards, but I wouldn't flip it without confirmation. Looks like flipping it will shift the ring gear forward, is that what you need?

nate99

Flipping it would put the ring gear where I need it, or at least move it in the right direction.

I'm scouring the internet for ideas, and I found one place where it said that Pontiac flexplates will only go on one way, so it may just be a cheaply made part. Or something else entirely might be off.

mrvette

I was going to say that it could only go one way, but I not done a Poncho trans in over 20 years now, but that was my recollection also....

Do a search for a fellow named Ron Johnson, Potomac Pontiac....is the business name, I knew him back when....been over 20 years now....he was a good man, maybe not the cheapest guy around, but now a daze you gotta figger those parts outta production over 30 years now....

more than anything, I suspect your flex plate is fine,...and the aftermarket starters are not made correctly, most likely a CHINA import.....

what you maybe able to do is change the starter bolts for ones of similar length, or use a larger nut/washers as spacers under the bolt heads....starter bolts are fatter along the shank for alignment purposes, and so maybe a skinnier bolt will allow fore some slop....you need pull the Bendix spring to the rear to engage the flex place teeth, I used to do it manually, but if you pull the tab off the motor side, you can do it electrically, but that's a bit of a mess doing it that way....get some piece of really stiff steel wire and bend a hook on the end, use that to grab the Bendix......

ramair_bryan

Can't be any of my pontiacs.............there'd be oil streaming down the pan, flex plate, trans..................

nate99

Thanks. I'll probably go back with a stock replacement. I did install a remote (Ford) solenoid, so hopefully my heat soak issue won't be a problem.

Just a slow ooze around the back of the oil pan.

mrvette

Then you must be running the rope seal, there is a CADDY seal from a 500 ci engine that will fit that Poncho 428 as I recall the main was 3.25" and so the caddy seal is two crescent shaped rubber inserts with a steel wire insert, the install is pretty easy, but you have to match the ends as they maybe made a bit long, so to grind them down till the two sections form a perfect circle laid out on the bench....use a small dap of RTV black when I finally figgered out I had to grind/match the seal into a perfect circle, all the leaks were fixed at that point,......