Yet another metric 200 question
 

What causes the front pump seal to blow out. I just got this transmission and put it in my car and it blew fluid everywhere. The seal was out of the pump completely. I don't know much about the thing like who built it. I thought it was odd that the cooler ports were plugged.

Re: Yet another metric 200 question
 

Good morning Mike and to all,
Without knowing whether this trans is in a Stocker or a Super Stocker, internal pressure will push out the front pump seal. GM has a retainer for the front seal but you might need to check that the vent for the case isn't blocked or restricted. Depending on who actually built the unit and who's valve body has been installed will determine why the cooler lines are plugged. My McClay unit has a loop, my Leon trans is plugged. You might want to reach out to Mark Yac. that comes on this site, he might be able to give you some guidance. If someone in Mike's area knows of a good builder, maybe you could chime in here and get Mike some help.
Have a Good Day.

Respectfully,
Henry Kunz 1534 H/SA

Re: Yet another metric 200 question
 

Mike, I've never seen a chronic case of seal blowout. Depends on how much pressure is behind it, and why. Is it a 350 converter conversion? Has the stator support been replaced? never used Loctite on a front seal but I suppose you could.
Most transmissions have an internal cooler bypass for cold climates. Usually one would completely remove the bypass and let the fluid make the loop internally. Not a big deal, if you don't want to run a cooler..I do, always. . One run ,every three or four hours? No big deal... Gas and go, turn 'em and burn 'em in a hot climate, late rounds? Different story..

Re: Yet another metric 200 question
 

Two ways to cure this problem. first is to make sure the converter bushing is in good shape and has the proper clearance to the converter neck, second is to open up the drain back passage that vents behind the converter seal . A 200 has a cast iron pump and the press fit for the seal is pretty robust. The 4L60 had an aluminum pump, and had a problem losing the converter seal , so a seal retainer was designed that pressed on over the seal to retain it, due to loss of press fit as the aluminum pump expanded as it heated up. Cast iron pumps don't usually have this problem. Your problem is probably caused by excessive leakage getting into the pocket behind the seal, so that clearance between the converter neck and the bushing is probably where that leak is coming from. Let us know what you find !

Re: Yet another metric 200 question
 

This is a G/SA car that is not real fast. I did replace the seal and it was a tight fit. I also found that the converter snout looked burnt so I put a new converter in it. I will run it tonight and see what happens. It looks like the stock pump and maybe stator too in it.

Re: Yet another metric 200 question
 

Ran the car last night and did not have any issue with front seal. We will see how it does at the national in Ennis. Hope it?s faster than the turbo 350 I just took out.

Re: Yet another metric 200 question
 

Anyone know the weight difference between a turbo 350 and a metric 200. Just wondering if I need to add weight.

Re: Yet another metric 200 question
 

Totally stock 350 is about 122 pounds whereas a totally stock 200C comes in about 96

Re: Yet another metric 200 question
 

Thanks. If it?s that much I better add a little weight tonight so I don?t get dq?d.

Re: Yet another metric 200 question
 

Mike , take your car , race ready down to the scales before you make a run, and weigh it. The scales are usually open, and it is a lot better not to guess when you make your first run ! Good luck

Re: Yet another metric 200 question
 

Good morning to all,
The TH350 I weighted was without a converter or fluid and it was 115 lbs. my TH200 without a converter or fluid 98 lbs. , so if you error towards the high side 20 to 25 lbs. you will be slightly over weight when you put your car on the scale. I'm also sure there are variations between transmissions and scales so use these numbers as a guide, your outcome may vary.

Respectfully,
Henry Kunz 1534 H/SA

Re: Yet another metric 200 question
 

So I put 20 pounds in it and went up for Q1 and was 10 pounds over at the scales. Glad I put the weight in because that run would not have counted.

Re: Yet another metric 200 question
 

On Q1 the transmission shifted like an old cadillac. I clamped off the cooler lines for Q2 and it shifted firm but blew the front seal out at the finish line. The good news is the car picked up over 4 tenths and 3 mph from the turbo 350.

Re: Yet another metric 200 question
 

Just to be clear here... You said the cooler lines were plugged but now you have a cooler?
The 4 tenths you picked up was with a different converter?

Re: Yet another metric 200 question
 

No, the 4 tenths was after I clamped the cooler lines off. I did find out the builder was Billy Lynn. I hope I got the name right. Technically it was a different converter and transmission.

Re: Yet another metric 200 question
 

Okay...I'm Lost in the Ozone Again

Good luck...

Re: Yet another metric 200 question
 

Clamping off the cooler lines changes the way the pressure regulator works, resulting in way higher line pressure, but also prevents lube and cooler flow. The result of that will be an over pressurized converter which could / will lead it to ballooning , plus no lube flow will burn up the clutches and bearings. This is obviously no good for the transmission . If you are having line pressure issues, hook up a line pressure gauge to help diagnose the problem .

Re: Yet another metric 200 question
 

So I got the bushing out of the front pump and studied it. It has a lot of wear on one side and has never touched the converter on the other side. Looks like the ultra bell housing is not lined up and causing misalignment between the crankshaft and the transmission input shaft.

Re: Yet another metric 200 question
 

The bushing in the pump needs to be centered on the crankshaft centerline. I built a tool that centers the bellhousing on the crankshaft bore and then allows the pump bushing to be centered on the tool. This allows the pump to be aligned and pinned to the bellhousing . With the transmission aligned with the crankshaft, bushing wear is reduced significantly and oil leakage is way reduced. You will need an engine block , a piece of aluminum round stock about 18" long and a good machinist with a lathe. You need to pickup at least two of the back main bearing bores and machine the round stock to fit line to line in those bores. The rest of the round stock projects out the back of the block, allows you to machine it so the pump bushing is a close slip fit. Once the alignment tool is made , you bolt it into the block, install the bellhousing, then slip on the pump body with the bushing installed. The pump body can now be drilled for two small pins 180 apart so the pump stays on center with the bellhousing. The problem with those aftermarket bellhousings is it counts on the bolts to align it with the pump, but the bolt holes are clearance holes and will allow the bellhousing to runout quite a bit. Once the bellhousing is aligned and pinned to the pump, it will run on center.

Re: Yet another metric 200 question
 

What you're seeing on the bushing wear isn't necessarily an ultrabell problem. The discharge side of the pump forces the gear and converter neck to one side from the hydraulic pressure so wear on one side is normal.. That said, hanging the bell housing on 6 8mm bolts doesn't guarantee good alignment.