BuffaloBillPatri Posted September 1, 2010 Share Posted September 1, 2010 I think I fixed my flex-plate runout, it was about 1/8" & messing with starter engagement. It seems? that one of the ears on the B&M Holeshot 3000 converter was bending the flex-plate upon torquing the bolts. I seem to have fixed it by putting thin flat washers between 2 of the ears & flex-plate. Runout looks even to starter pinion gear now & about .100" Anyone else ever seen this? BBP Quote Link to comment Share on other sites More sharing options...
BuffaloBillPatri Posted September 1, 2010 Author Share Posted September 1, 2010 A guy on another site brought up a balance issue. I will go add a washer to the 3rd bolt, but under the head & not between the flex-plate & converter. BBP Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted September 1, 2010 Share Posted September 1, 2010 Something seems fishy here. The flexplate and the torque converter should be perfectly perpendicular to one another. Are you sayting they are not? When checking how they mount up together, I have always gone by this: "The best way to be absolutely certain that the converter is fully indexed into the front pump is to place the transmission/converter assembly up against the back of the engine. The bolt lugs on the converter should not be touching the flex plate. There should be a gap between the flex plate and the converter bolt lugs. With the transmission bolted to the engine, this gap should be approximately 3/16” but no more than ¼”. (If the gap is larger than ¼”, precision shims must be installed to obtain the proper gap before the converter bolts are installed.). Before installing the bolts into the converter lugs you will need to slide the converter forward to the flex plate. If a gap doesn’t exist, the converter isn’t indexed into the pump properly. To get it to index into the pump, you need to continue turning the converter, at the same time, applying slightly inward pressure until it fully engages. Another easy way to check when using a full size converter is to try and slide your fingers between the converter and the pump housing. If you can, the converter isn’t fully engaged. This test doesn’t apply to the smaller v-6 or small diameter high stall converters." I have had to get hardened washers and put them between the converter and the flexplate, but I'm not fully understanding what you did??? Quote Link to comment Share on other sites More sharing options...
BuffaloBillPatri Posted September 1, 2010 Author Share Posted September 1, 2010 Thanks, I will copy & save that info. I had about 1/4" or so clearance, converter was easy to slide up to flex-plate & think it's engaged & indexed properly. I put washers between converter ears & flex-plate, 2 of the ears, a washer each. I know somethings fishy. I think one or more of the ears are not quite parallel to the flex-plate, B&M issue I believe. BBP Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted September 1, 2010 Share Posted September 1, 2010 I'd take that converter back to where I got it from and get a new one then. Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted September 1, 2010 Share Posted September 1, 2010 I know it sound like a hassle but if the lugs are not right I would pull it out. They should have better quality control than that. I wonder if it has other issues? Quote Link to comment Share on other sites More sharing options...
stangeba Posted September 1, 2010 Share Posted September 1, 2010 A new flex plate is part of a kit we sell at Stovebolt, to adapt an old six cylinder engine to new automatic transmission. Tom must check each and every new flex plate for run out both of the ring gear and front to rear run out or wobble. Just last month he returned 29 out of 30 new flex plates for being out of spec. FYI Bruce Quote Link to comment Share on other sites More sharing options...
wallaby Posted September 1, 2010 Share Posted September 1, 2010 Ok, this bothers me. I know you found a solution, but I'm not convinced it's any better. The real problem here is a mis-alignment issue, and we don't know what's causung the problem. All we know is that when we bolt the trans to the engine and try to mate the converter to the flexplate, the two pieces are joining at an angle. The trans could be crooked to the engine, or the flexplate could be bad, or the converter might not have equal ears, or the hub in the center of the converter might not be engaging the tail of the crankshaft correctly. Your repair with the washers assumes the flexplate is true, and mounts the converter at an angle to keep it that way..so now the output shaft on your converter is wanting to wobble in the trans. I don't have a problem with using a washer at EVERY mounting point to move the converter straight back, but until you know for sure where the machining error is, using selective spacers is going to set you up for failure later. To solve the problem you need to measure the runout on the converter pads of the flexplate to make sure the plate measures flat. (are they equal? is the ring gear running straight and round?) then bolt the converter to the flexplate and measure the runout on the converter output shaft. If the flexplate measured ok, but the converter shaft has wobble, the problem lies in the converter assembly. Ironically, the washers might be the solution to get the output shaft to run true: but you don't know that until you take the measurements. Quote Link to comment Share on other sites More sharing options...
BuffaloBillPatri Posted September 1, 2010 Author Share Posted September 1, 2010 I bought flex-plate & converter about 15 yrs. ago from Summit. I don't even find the receipts. Just now getting my 72 Monte running again. My son was taking HS auto shop & wanted to rebuild the motor, he just took it apart & lost interest. I had 2 incomes at the time so I bought a lot of speed parts for it, then I lost interest as other more important things came up. Now I'm retired & have the time. So these are new parts, but without any chance of returning them. The flex-plate was being forced to bend as the bolts were tightened down. With the washers, it now has very little runout vs. the starter pinion gear. The converter etc. may have a short life do to wobble. I will find out, because I'm going to drive it & see, street only, will see 6K RPM. BBP Quote Link to comment Share on other sites More sharing options...
wallaby Posted September 1, 2010 Share Posted September 1, 2010 Chances are good that if a problem arises, it will be cracking of the flexplate. Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted September 1, 2010 Share Posted September 1, 2010 I honestly wouldn't do it. You could damage the rear crank bearing, the trans pump, the converter, flexplate or all of them. It won't matter if you spin it 6000 or 3000. And just because it's on the street doesn't mean it won't break. A little trip to the gas station can take as long as a whole days worth of run time on a dragstrip. Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted September 2, 2010 Share Posted September 2, 2010 did you try "clocking" the converter to different positions on the flywheel to see if it changed? Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 2, 2010 Share Posted September 2, 2010 i had a similar problem.. I didn't slide the converter up against the flex plate firmly, and when I tightened the converter bolts, it warped the flex plate and then when I started the engine, it was hammering the torque converter in and out.. it demolished my front pump... (which is what started the 700r4 project) Quote Link to comment Share on other sites More sharing options...
Winston Wolf Posted September 2, 2010 Share Posted September 2, 2010 i had a similar problem.. I didn't slide the converter up against the flex plate firmly, and when I tightened the converter bolts, it warped the flex plate and then when I started the engine, it was hammering the torque converter in and out.. it demolished my front pump... (which is what started the 700r4 project) Thanks for the first hand post, that's exactly what I an betting on will happen here.....unfortunately. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 3, 2010 Share Posted September 3, 2010 n.p I kept my th350c tho... one of these days when I get the motivation.. I'll find a new front pump for it. the trans still works ok.. it just slips really bad when the engine is below 2000 rpm. i drove the 150 miles round trip to one of leo's mini-meets with it like that so as long as I was turning more then 2000 rpm it wasn't terrible. (thankfully i had my 3.55 gears then so doing more then 2k was only an issue from a stand still Quote Link to comment Share on other sites More sharing options...
Andy's Auto Posted September 4, 2010 Share Posted September 4, 2010 Just got to throw this out there. If you push the convetor out to the flexplate with the trans installed and the lugs don't all meet, look for debris or a bent hub on the convertor. These things get kicked around and generall abused before sale and you might just have a nick or a bend on the convertor hub that centers it to the rear of the crank. I have even seen rust and scale on the crank where the flexy bolts to it. Step one, pull the trans back out to see if the flywhhel is indeed true. A dial indicator rocks for such things. Set the indicator on the block. Look while someone turns the engine from the crank bolt. Any out of round issues will sjow itself. If that ckecks out, grab the convertor and place it on the flexy and see what happens. Like everyone said, runout on the convertor will kill that trans pump. I know it sucks to pull the trans back out. Man up, it is a 45 minute job on your back, 20 minutes on the lift. Andy Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 4, 2010 Share Posted September 4, 2010 unless it's a 700r4.. then it's just about suicide on your back.. LOL (or a 4l80e) Quote Link to comment Share on other sites More sharing options...
BuffaloBillPatri Posted September 9, 2010 Author Share Posted September 9, 2010 My converter wobbled too much, could feel it in my feet. I have now put 1 small diameter flat washer between each converter ear & flex-plate. I don't see any front to rear runout of flex-plate & don't feel any wobble. Hope this is a good fix. BBP Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 9, 2010 Share Posted September 9, 2010 the only problem with that BBP... is now the nose of the converter can't center the converter on the crank's pilot bearing.. (been down that road too) Quote Link to comment Share on other sites More sharing options...
BuffaloBillPatri Posted September 9, 2010 Author Share Posted September 9, 2010 I don't understand why the centerlines wouldn't align properly? The converter is about 1/16" straight back toward the TH400 BTW, I don't think I have a pilot bearing? as in a stick-shift pilot bushing bearing. BBP Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted September 9, 2010 Share Posted September 9, 2010 The nose of the torque converter is the pilot. If you look at the nose there is usually a raised area that indexes the converter to the crank. There is no pilot bushing involved. If you pull the converter all the way into the crank hub and you loose alignment something is wrong. Quote Link to comment Share on other sites More sharing options...
wallaby Posted September 9, 2010 Share Posted September 9, 2010 I like the idea of equal washers under the ears better than what you had previously. It sounds as if you have a conflict somewhere where the converter hub meets the back of the crankshaft. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 10, 2010 Share Posted September 10, 2010 by spacing the converter back however, you are preventing the nose of the converter from centering on the back of the crank correctly. Quote Link to comment Share on other sites More sharing options...
BuffaloBillPatri Posted September 26, 2010 Author Share Posted September 26, 2010 It sat for 14 years without the bolts. Maybe some dirt blew up in there. I have tremendous winter winds, 120MPH sometimes. Jet Stream comes over the mountains just West of me. The wind actually ripped the front license plate off the bumper over a couple winters. I will unbolt it again & squirt WD-40 up into the snout area. BBP Quote Link to comment Share on other sites More sharing options...
Heckeng Posted September 27, 2010 Share Posted September 27, 2010 I have the solution. It's time to install some 4.56 gears in that thing! You'll never go that fast again. Quote Link to comment Share on other sites More sharing options...
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