Just installed a flt level 4 and SS3600 converter on my 98 ta. I am using stock flex plate. I started it up today and saw sparks out of the inspection plate. Shut it off instantly and crawled under.

I had a friend helping with the install and he tightened down the converter bolts (we used my stock bolts) well when I crawled under I could see like 2-3 threads of each bolt. So they were actually tight... But not pressing against the flex plate at all. I didnt notice it before hand because I measured the gap with a drill bit and was perfect.

So do I need to order shorter bolts, or am I able to just go to ace hardware and pick up a shorter bolt?

 

what was the gap from the converter to the flexplate?

 

I have used Grade 8 (for US thread) or 8.1 or 10.1 (for Metric) bolts from my local hardware store for 10+ years on various cars. Assuming a 12" diameter (and 6" radius) converter, even a 1000 ft/lb engine is only going to put 2000 lbs of shear force spread over the three bolts, which is nothing for hardened bolts. The shear force on the 6 flexplate to crankshaft bolts is much higher. Just my opinion.

Sounds like your bolts are too long.

Is it important to lock-tite the bolts.

As mjs1012 said, what is the gap between the converter and flexplate? Optimal is 1/16" to 3/16". Any more and you should put matched-thickness washers between the converter and flexplate.

 

the gap was a perfect 3/16".

i just went and bought shorter bolts. they are now flush on the flexplate, but now the converter pads are flush against the flexplate...??

any help?

 

The converter pads are supposed to be flush against the flexplate with the bolts holding them tightly together.

The converter is designed to move in and out of the trans a bit.

Or am I misunderstanding your question.

 

this thread says otherwise: https://ls1tech.com/forums/automatic...lations-2.html

it says there should be a 1/16"-3/16" gap in between the the flexplate and converter pads.

 

i bought some different bolts again. M10-1.5-20mm

installed all 3, torqued them to spec. (46 i have just shy of a 3/16" gap between the converter pads and the flexplate. but if i grab one of the bolts and try to wiggle it (up and down) it wiggles ever so slightly. im guessing this isn't supposed to happen....??????

 

You are misunderstanding this. This is the gap BEFORE you begin tightening the bolts. You must be sure that the bolts are not so long that they bottom out in the converter. 20mm sounds way too long. I think you are bottoming the bolts out in the converter when you torque them, thinking you are supposed to keep a gap between the converter and flexplate. NO. The pads are firmly mounted to the flexplate and torqued.
In other words, as you torque the bolts, the converter is pulled out of the transmission by between 1/16" and 3/16" inch.

Perhaps someone else can explain this better.

 

My converter (yank py3600) didn't line up with the same 3 holes in the pressure plate as the factory tc but lined up with 3 others perfect. Did yours do the same?

 

Ahic. I did totally missed understand it then... The 20mm or shorter then stock. But I also have 16mm. With the 16mm that is when there was a gap after tightening.

Is it to late for me to figure this out correctly? Do I just put the 16mm in and torque them and call it a day now? Or what should my next step be?

I appreciate the help man, I owe u a beer sometime if u ever move close to me lol.

 

So I just went out there to re measure. I pushed the converter all the way back and spun it a hand full of times. I was able to get a 7/32 drill bit in there.

How big of a washer do I need? Will home depot/ace hardware have them? Do I just place the washers on each bolt, correct?

 

I have dozens of Grade 8 3/8" washers and using calipers select three with the same thickness. I just measured some at .080; so just one between the flexplate and converter would be good. I find that metric washers seem to be made to a higher precision and therefore might be easier to match.

The task is more difficult with washers because you need to hold the washer between the flexplate and converter as you insert each bolt. You need to turn-in the first two bolts just enough so that the heads don't hit the engine block as you turn the crank, but not so much that you can't fit the washer into the 2nd or 3rd ones. Once the third bolt is in, you can then torque things down.

I suspect that 7/32 is still OK without a washer, but I've read the experts say 1/16" to 3/16" and I go with that. Too much gap and the converter will pull out of the trans pump, lose pressure and ruin everything.

Good luck.

 

the 3/8" washers i just picked up from ace were only .066". should i run 2 of them, or still only install one?

 

correct bolts are 12mm long with stock flexplate 16mm with SFI flexplate

 

Even though I have to run washers?

 

Just one should be enough. Also, I think your 16mm bolts should be fine, just as long as they don't bottom out before things are torqued.
In an old thread many people mentioned needing washers with most aftermarket converters.

 

I used 12mm arp bolts for my fti 3800...stock were too long.

 

Ended up using 1 washer on each bolt, 16mm 8.8 grade bolts, with red thread lock. Torqued down to 50ftlb. Started it up and took her for a drive. Everything feels good.