Ottoman

I'm in the Process of rebuilding my REW...

on my center plate on both sides.. near the "apex" of the football on the left.. there is a "rise" in the metal.. almost like it's bunched up almost like a very slight wrinkle on both sides of the faces... both end irons are flat...


i've taken the center plate to get machined... (they're no rotory specialist but they do cyl heads all day long)

a.) they said they have to remove the nipple on one side of the plate.. is it ok if i just plug it and leave it like that?

b.) how much "room" for machining is there on the centerplate? Do I just need a thicker spacer and that's it? The motor Already Had a C spacer in it when i opened it up...


Thanks,

kenn_chan

yes you can remove the nipple, just get a new one pressed in after the machining is done.

limits I think (best off to check the fsm) is like 2~3 thousandths (though many rebuilders take it much further).

yes you will need a new front spacer to set the endplay of the engine which spacer you need must be measured after you assemble the stack with a dial guage.

kenn

Ottoman

Thanks kenn...

The machinist gave me an approximation of 0.4 millimeters off each side of the center plate..

do you think that will render it useless?

C. Ludwig

iTrader: (27)

Yes. .4 millimeters is .016". About 4 times what you can safely remove.

FWIW, when you machine the plates and you end up with a "shorter" engine you need to go to a smaller spacer. Not a larger one. Thinner spacer provide less endplay. Thicker ones provide more.

Ottoman

I got the plate back,

the shop said it was 12 thou... per side...

the plate looks much better now...

there's parts that didn't even get shaved when making it flat that stayed their original color meaning they didn't get shaved...

if the engine was running a C spacer.. doesn't that mean i got plenty of room before i fall off the other end of the scale?

Thanks,

C. Ludwig

iTrader: (27)

First, .012" per side is 3-4 times more material than should be removed. The problem with machining that much is that you compromise the water jacket o-ring lands. If they have taken that much off the plate is junk.

Secondly, if the plate has high and low spots and some areas that weren't even touched the surface is not true and again the plate is junk.

Ottoman

man.. that blows... i just blew $50 for nothing...

just outta curiosity...

in the bruce rebuild... (which i haven't seen in awhile) in the scene where he's checking the plaets with the dial caliper..he says that there shouldn't be more than a variance of 4 thou.. otherwise it will need lapping/facing... doesn't that mean +/- 4 thou variation from the surface? but not the actual "deck height" itself...

i meant wouldn't the o-rings just be squeezed "a little tighter" that's about it?

C. Ludwig

iTrader: (27)

There really isn't a +.004" when you're checking the wear. Hard for material to build up on the iron. Just wear. Haven't seen his video but it sounds like he's saying if you see .004" wear then they need machined. But again, I haven't seen it.

The o-rings will be squeezed a little tighter but at some point they run out of room to be sqeezed and they lose the support of the side of lands.

Ottoman

I didn't think it could be Raised either..

but the whole surface was flat... and at the "apex" of the footbal.. the was a virtical Wrinkle that u could easily feel with a finger... almost like the metal Bunched up in that area...

sounds crazy i know... that's why i had wondered....

strange eh

SureShot

There are two issues when lapping the plates.
The depth of the O-ring groove, and the depth of the nitride penetration in the wear surface.

BTW the stack thickness does not affect the end play, which is strictly a function of the torrington bearings, the thrust disc, and the spacer.

Ottoman

Thanks for the reply..


I think it'll be best if I snap some pics of the housing tommorrow and post em up so ppl can see for themselves.. instead of trying to explain it...

trochoid

iTrader: (6)

With that much depth ground off, the nitride coating is gone. The center iron will now wear at an accelerated rated. Time to find a new center iron and use the old one as a door stop.