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Engine Specific Info and Questions => IDI Engine => Topic started by: sdwarf36 on October 06, 2011, 08:52:52 pm

Title: dead cylinder after rebuild
Post by: sdwarf36 on October 06, 2011, 08:52:52 pm
 :'( Fresh rebuilt on a TD-everything new + done right. Fresh rebuilt Giles pump-new injectors. But number 2 cylinder is dead.  (crack the fuel line-no change in running.)
 
 New pistons+rings-valves-valve job-even piston pertrusion-the right head gasket.  All built be me in a well equipt machine shop. Sent the pump to Giles-had someone test the injectors 3 were ok-replaced 1. Fired the car up -ran things long enuff to burp the cooling system+went for a test ride. You could tell right away it had a dead cylinder. Cracked the injector lines + found #2 didnt change anything. Bought 3 new (Bosch rebuilt) injectors. Still no change. Swap injectors around-still dead #2. Blew thru the fuel lines-all fine.
 I borrow an long unused comp tester from work. I cant get it to work all the way right (it wouldn't store the comp.It would jump up and start leaking before the next hit. Not perfect, but you could tell the hole wasnt dead) I check another cylinder + it SEEMS a bit higher. Paranoid about everything inside, I tear it back apart. The rings were not broken-the valves are sealing fine-the lash is correct. Nothing wrong with the head gasket. The piston looked a little more "washed" than the others. (like its not firing very good--not dead but not well.)
 Not sure what to do next, I call Giles+ tried to see if he has any ideas. ( i had worries about the pump because it sat over a year after being built.) I decide to send the pump to him to be retested.
 I didnt like the looks of the wear pattern of the rings (what ever came with Topline pistons) so i replaced them with a set of Sealed Power rings + set the gap at .014.

Giles retested the pump-and everything checked out fine. I reassemble the motor-install the pump (set at .95) + refire it. still no change with you crack the #2 fuel line. A test ride comfirmed that its missing a cylinder.

So the motor has been rebuilt twice--the pump has been tested twice-the injectors have been swapped from cylinder to cylinder-but still no fire from #2. Any ideas? even crazy ones at this point will be considered. :'(
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 06, 2011, 09:14:32 pm
Any ideas? even crazy ones at this point will be considered. :'(

Buy a new #2 injector line.  :-X

What were the compression numbers? I have a leak free comp tester if you want to borrow it.
Have you done a leakdown test?
Title: Re: dead cylinder after rebuild
Post by: Mark(The Miser)UK on October 07, 2011, 02:02:27 am
Check that your issue isn't a cracked injector boss.

How does your water system behave, pressurewise?
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 07, 2011, 03:13:17 am
The only place it was leaking down was past the rings the 1st go round. Under 10%. More than I like, but not suprising for a 'wet" cylinder with the rings not fully seated in.

 What do you mean by injector boss?
 I'm gonna try an other  set of injector lines off my old motor next.
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 07, 2011, 04:15:47 am
Injector is married to the cyl head. Guess who the injector's boss is? ;D
Title: Re: dead cylinder after rebuild
Post by: Mark(The Miser)UK on October 07, 2011, 04:27:37 am
Injector is married to the cyl head. Guess who the injector's boss is? ;D
Sleepless in New York? ;D

The boss is the threaded injector's socket on the head.

A diesel gauge should not fluctuate, as it should have a one way delivery valve down by the adaptor end. Dismantle and inspect for crud, and recheck compression.

Forget injector lines unless you have a cloud of fuel when running, or at the least a drenched connector.

 Even with my engine's ring gaps at 160 thou,and at least one ring stuck in, I had nearly 200 psi on cranking.
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 07, 2011, 04:42:16 am
Injector is married to the cyl head. Guess who the injector's boss is? ;D
Sleepless in New York? ;D

The boss is the threaded injector's socket on the head.

A diesel gauge should not fluctuate, as it should have a one way delivery valve down by the adaptor end. Dismantle and inspect for crud, and recheck compression.

Forget injector lines unless you have a cloud of fuel when running, or at the least a drenched connector.

 Even with my engine's ring gaps at 160 thou,and at least one ring stuck in, I had nearly 200 psi on cranking.

Nah just woke up early. I said change #2 injector line tongue in cheek since that was the only item not swapped. If there's fuel and compression and timing is correct it's gotta run.
Title: Re: dead cylinder after rebuild
Post by: Mark(The Miser)UK on October 07, 2011, 05:04:24 am
Injector is married to the cyl head. Guess who the injector's boss is? ;D
Sleepless in New York? ;D

The boss is the threaded injector's socket on the head.

A diesel gauge should not fluctuate, as it should have a one way delivery valve down by the adaptor end. Dismantle and inspect for crud, and recheck compression.

Forget injector lines unless you have a cloud of fuel when running, or at the least a drenched connector.

 Even with my engine's ring gaps at 160 thou,and at least one ring stuck in, I had nearly 200 psi on cranking.

Nah just woke up early. I said change #2 injector line tongue in cheek since that was the only item not swapped. If there's fuel and compression and timing is correct it's gotta run.
There was me thinking he'd used a timing dial gauge by mistake seeing as it goes up and down ;D
Title: Re: dead cylinder after rebuild
Post by: nathan_b on October 07, 2011, 11:04:52 am
comp /leakdown test results??

that will tell you 90% of the problem right there/
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 07, 2011, 12:14:35 pm
Leakdown on the 1st set of rings was about 9%. The comp tester wouldn't keep a number + build on it ( 200 1st crank-300 2nd crank-350 3rd crank etc) but it was going to 190 1st crank--so there was comp there.

 Water temp was fine--wasnt blowing any out--head gasket was perfect.
 No leaks around the injector while running either.
Title: Re: dead cylinder after rebuild
Post by: nathan_b on October 07, 2011, 12:32:50 pm
did you have a new heat shield under injector?
Title: Re: dead cylinder after rebuild
Post by: Mark(The Miser)UK on October 07, 2011, 01:16:01 pm
Leakdown on the 1st set of rings was about 9%. The comp tester wouldn't keep a number + build on it ( 200 1st crank-300 2nd crank-350 3rd crank etc) but it was going to 190 1st crank--so there was comp there.

 Water temp was fine--wasnt blowing any out--head gasket was perfect.
 No leaks around the injector while running either.

OK apart from going on a "Fantastic Voyage" with Raquel Welch inside your preghamber, this test will solve the issue:

Undo the clamps holding the high pressure injector fuel line cluster.
Remove line #2 and the inhjector.
Reconnect upside down from the pump outlet. Screw the injector back on and start engine. Observe for a few seconds and shut down engine.
All fueling issues will be revealed. Don't worry about the diesel, it will be a small vapour cloud which will float away. An assistant starting /stopping engine can help, or pull the stop solenoid wire...
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 07, 2011, 01:26:22 pm
Leakdown on the 1st set of rings was about 9%. The comp tester wouldn't keep a number + build on it ( 200 1st crank-300 2nd crank-350 3rd crank etc) but it was going to 190 1st crank--so there was comp there.

 Water temp was fine--wasnt blowing any out--head gasket was perfect.
 No leaks around the injector while running either.

OK apart from going on a "Fantastic Voyage" with Raquel Welch inside your preghamber, this test will solve the issue:

Undo the clamps holding the high pressure injector fuel line cluster.
Remove line #2 and the inhjector.
Reconnect upside down from the pump outlet. Screw the injector back on and start engine. Observe for a few seconds and shut down engine.
All fueling issues will be revealed. Don't worry about the diesel, it will be a small vapour cloud which will float away. An assistant starting /stopping engine can help, or pull the stop solenoid wire...

I'd suggest sticking the injetor into a clear Snapple bottle with a tissue in it. You'll see if the injector is spraying and the tissue will soak up the spray (if any) so you can smell it if you can't see it.
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 07, 2011, 03:36:49 pm
did you have a new heat shield under injector?
Yes-and in the right direction. 1st was the bronze? one that came with the gasket set-then a steel one with the new bosch injector.

 Good idea on bench testing the injector-gonna try that tomorrow.
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 08, 2011, 11:31:53 am
Does this spray pattern look normal? this is from the pump outlet for my #2 cylinder? I ran 3 differnet injectors and they all looked the same. http://www.youtube.com/watch?v=z0gOuSEbpyI

I also found a better comp tester. I get 350 psi-(leaving the other 3 injectors in. It would be higher with them out.) Plenty enough that the cylinder should fire. Out of desperation, I even tried a different fuel line.
Title: Re: dead cylinder after rebuild
Post by: rabbitman on October 08, 2011, 01:00:33 pm
That spray looks fine to me.
Title: Re: dead cylinder after rebuild
Post by: Mark(The Miser)UK on October 08, 2011, 02:21:28 pm
Does this spray pattern look normal? this is from the pump outlet for my #2 cylinder? I ran 3 differnet injectors and they all looked the same. http://www.youtube.com/watch?v=z0gOuSEbpyI

I also found a better comp tester. I get 350 psi-(leaving the other 3 injectors in. It would be higher with them out.) Plenty enough that the cylinder should fire. Out of desperation, I even tried a different fuel line.

Compression sounds  fine.
The injection seems ok. Especially as the other injectors give same pattern.
It would have been easier to tell if the camera was back a little more, and the target was perpendicular  to the spray perhaps 1ft to 18" away.
A further test  for comparison would be to do the same  trick with one of the other fuel lines, just in case the problem is in the delivery valve.
Good luck.[three hours between writing and posting!]
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 08, 2011, 03:13:42 pm
Tested a few more things. I did a leakdown-7% leakage-all past the rings. not suprising considering this cylinder has never fired to put a load on the rings. Also tested compression on a running cylinder-close to 500.  A little more difference than I thought-but its a seated ring vs a washed out one.
Title: Re: dead cylinder after rebuild
Post by: rabbitman on October 08, 2011, 05:30:29 pm
350 psi is plenty enough to get it to fire.

With 350psi, a good injector and injector line and still a dead cylinder I think it's time to look elsewere, the delivery valve would've been rechecked by Giles so that shouldn't be an issue.

You didn't leave the exhaust lifter out of that cylinder..........
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 08, 2011, 07:12:57 pm
No-i remembered all the valves + buckets. Lash is on the money too.
Title: Re: dead cylinder after rebuild
Post by: maxfax on October 08, 2011, 08:01:06 pm
Did you forget and leave your "stash" in the #2 intake runner?  ;D
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 08, 2011, 08:27:53 pm
Something in the intake port crossed my mind too-but without air you wouldnt get compression.
Title: Re: dead cylinder after rebuild
Post by: rabbitman on October 08, 2011, 08:38:48 pm
Something in the intake port crossed my mind too-but without air you wouldnt get compression.

That's why I thought exhaust side. This is weird.

It sounds like you have timing way off on one cylinder, not possible.

Did you try taking all of the injector lines off and cranking it so you can see the order of injection? Not like that can change either but I'm about out of ideas.......
Title: Re: dead cylinder after rebuild
Post by: maxfax on October 08, 2011, 08:41:44 pm
Well, yes and no..  Thinking out loud here - It was pretty common back in the final days of GM using flat tappet cams that the lobes would wear off rather quickly.. Typically you'd have a very weak or dead hole with a low compression reading.. Although in your situation you still seem to have about 70% compression which is much better than the 40 some percent that would usually be found on those.. And enough that it should at least fire somewhat..   Plus I would think that whatever is stuck in there would have gotten sucked though the engine by this time..   For spits and giggles your could try the leak down tester on the intake and exhaust strokes to see what may happen..


Had you tried another #2 injector line??  I missed you mentioning it if you did...

I'm on the same page as rabbitman at this point..  I don't see how a pre-cup could really be screwed up as they usually just fall out or explode.. But who knows..  I've run into the exact same situation you are having on the old Case power-cell diesels.. The power cell (basically a pre combustion chamber) burns out so to speak.... The cylinder will have good compression and fuel but no fire till you replace the power cell..
Title: Re: dead cylinder after rebuild
Post by: rabbitman on October 08, 2011, 08:44:34 pm
For spits and giggles your could try the leak down tester on the intake and exhaust strokes to see what may happen..

You mean to check if there's "open valve flow" or "open valve with something else stuck in the port flow" right?
Title: Re: dead cylinder after rebuild
Post by: maxfax on October 08, 2011, 08:50:46 pm
For spits and giggles your could try the leak down tester on the intake and exhaust strokes to see what may happen..

You mean to check if there's "open valve flow" or "open valve with something else stuck in the port flow" right?

You got it..  At this point I guess it can't hurt.. If nothing else maybe it'll lead him to something totally unrelated that is causing the problem.. It's happened to me more than a few times while chasing odd ball issues like this..
Title: Re: dead cylinder after rebuild
Post by: 81 vw pu on October 08, 2011, 10:02:50 pm
A friend of mine did a rebuild on a 89 ford ranger 2.3 years ago and after a full rebuild had a dead cylinder with good compression/fuel and fire.
About drove him nuts trying to figure out what was going on. Ended up being a plugged exhaust port in the exhaust manifold on a runner with a sharp turn.
It was oil carbon from broken rings on that cylinder that was ran for who knows how many miles. No. 2 exhaust port on the vw td is fairly short but can be checked with a leakdown test with the exhaust valve open.
Title: Re: dead cylinder after rebuild
Post by: nathan_b on October 09, 2011, 05:05:17 am
Something in the intake port crossed my mind too-but without air you wouldnt get compression.

I know for a fact that a 1.8t engine will make 120psi compression with no cam even in it. so while you do need air, not as much as you would think..
Title: Re: dead cylinder after rebuild
Post by: Squidbait on October 09, 2011, 06:31:11 am
Sorry if this is a dumb comment, I'm still a total noob as far a diesel is concened.... but I don't see a mention of glow plugs.  Can you get combustion from cold on compression alone?
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 09, 2011, 07:58:11 am
You have enough compression, leakdown test not bad, you are getting fuel (at least #2 inj is spraying into open air). Maybe somehow fuel is not getting into #2 cylinder? I'd, in addition to looking for blockages in the exhaust already suggested, check for blockages in the swirl chamber. Take the injector out and blow air into #2 hole and verify there's no clog. Do it with valves open and closed and listen at the appropriate ports.
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 09, 2011, 08:39:36 am
When I had the head off last week, all the precups were fine-still tight + flush with the head. **remembering something here--one cup was cracked real bad-so i replaced it with one off another head-a non turbo one. They were identical with the exception of material-the td's arent magnetic. I'm not sure what cylinder it went in though. I looked VERY close side to side with TD's vs. NA's-exactly the same. Clutching at straws here...
 I managed to hit 10 psi boost on my test ride-so my stash probably would have blown thru the port + hung up under the valve.  :-[
 It starts easy+ idles fine-except with a minor shake. while glow plugs wouldn't make a difference-they are all new+ working.
 Yes-the fuel line was changed.
The intake manifold is a gasser-the ex manifold is an unknown brand aftermarket one-that I had to do plenty of welding + flattening of surfaces-so both have had my hands all over them-neither plugged.
 The cam is in perfect shape-and the lash is correct.
 So today i'm gonna try to blow air in the cylinder with the valves open to see it it comes out easy. After that gonna try to put my old NA IP on-just out of lack of other things to try.
 I really appreciate all the ideas guys-thanks!
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 09, 2011, 10:57:11 am
I would not swap IP to the NA until everything else is exhausted. I doubt a Giles pump checked twice by him can be the issue. Is #2 not firing at all? That just seems impossible! If #2 is indeed not combusting the fuel, its glow plug should be soaking wet. Have you pulled #2 glow plug to inspect after running it?
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 09, 2011, 11:22:16 am
DING-DING-DING!!!! WE HAVE A WINNER! It wasnt my stash stuck in a port--it was a sock. :-[ :-[ I still had the hose hooked up from the leakdown test so i pulled the vavle cover to check lobe position-i bumped it over to open a valve-put full air press to it-plenty of wind out the exhaust--turned over to intake+put the air too it--phfffttt-BOOOP_PFFFFFFTTTT!. I pull off the rubber boot to the inktake + start fishing around with a coat hanger-+ out comes a sock! I know at some point i had one over the end of the intake to keep crap out!  I had plenty hanging out so i would see it and NOT ever get it sucked in--guess that plan didnt go so well--huh? This F***ing sock cost me about $800!

Again--thanks for all the help! Max-I guess that karma for giving you the hub cap clips was a good thing!
Title: Re: dead cylinder after rebuild
Post by: 8v-of-fury on October 09, 2011, 11:53:31 am
a ****ing sock?

That's got to be the worst luck possible right there.. :(

Glad you got iy figured out ;)
Title: Re: dead cylinder after rebuild
Post by: R.O.R-2.0 on October 09, 2011, 12:05:32 pm
When I had the head off last week, all the precups were fine-still tight + flush with the head. **remembering something here--one cup was cracked real bad-so i replaced it with one off another head-a non turbo one. They were identical with the exception of material-the td's arent magnetic. I'm not sure what cylinder it went in though. I looked VERY close side to side with TD's vs. NA's-exactly the same. Clutching at straws here...
 I managed to hit 10 psi boost on my test ride-so my stash probably would have blown thru the port + hung up under the valve.  :-[
 It starts easy+ idles fine-except with a minor shake. while glow plugs wouldn't make a difference-they are all new+ working.
 Yes-the fuel line was changed.
The intake manifold is a gasser-the ex manifold is an unknown brand aftermarket one-that I had to do plenty of welding + flattening of surfaces-so both have had my hands all over them-neither plugged.
 The cam is in perfect shape-and the lash is correct.
 So today i'm gonna try to blow air in the cylinder with the valves open to see it it comes out easy. After that gonna try to put my old NA IP on-just out of lack of other things to try.
 I really appreciate all the ideas guys-thanks!

well, then one head was rebuilt with steel pre-cups..

inconel is non-magnetic IIRC..

glad you got it running.. if i were you, i would BURN that sock..
Title: Re: dead cylinder after rebuild
Post by: ORCoaster on October 09, 2011, 12:15:45 pm
I would encase the sock in plastic and hang it off the jockey box door.  When people ask what is with that?  You can tell them that is the most expensive sock you own, 800 each or 1600 a pair. 
Title: Re: dead cylinder after rebuild
Post by: sdwarf36 on October 09, 2011, 01:40:48 pm
It will go up on the "wall of shame" with broken dragbike pistons-bent race car parts etc. :P Just got back from a test ride-it feels a world better running on 4. Gotta turn down the smoke a little bit though....
Title: Re: dead cylinder after rebuild
Post by: Mark(The Miser)UK on October 09, 2011, 04:57:39 pm
It will go up on the "wall of shame" with broken dragbike pistons-bent race car parts etc. :P Just got back from a test ride-it feels a world better running on 4. Gotta turn down the smoke a little bit though....

At least your car would go over 5mph, but then again my swallowed hankerchief was found after 200 yards 3 annoyed drivers' horn blares and 10 minutes under the hood  :P
(http://img28.imageshack.us/img28/4010/bungedupturbo.jpg) (http://imageshack.us/photo/my-images/28/bungedupturbo.jpg/)
Title: Re: dead cylinder after rebuild
Post by: maxfax on October 09, 2011, 05:39:13 pm
There is no way to describe how hard I laughed after reading this...  Karma indeed because I was kind of being a smart ass when I originally posted about your "stash" being in the intake runner..  :P   Glad you got to the bottom of it anyhow..  And for some positive thinking, imagine how much that sock would have cost had it got sucked in there a bit further!  You should see what the yellow pages does when sucked in to a runaway 671 Detroit...
Title: Re: dead cylinder after rebuild
Post by: ORCoaster on October 09, 2011, 07:51:07 pm
Brings a whole new meaning to "Stick a sock in it buddy!"
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 10, 2011, 07:24:21 am
Was the sock between the turbo and the inlet manifold? Shame you didn't find the sock after you tore the engine apart the second time.
Title: Re: dead cylinder after rebuild
Post by: Mark(The Miser)UK on October 10, 2011, 08:16:58 am
Are you in control of the other sock, or had you lost that one on some earlier car experimentation?
Title: Re: dead cylinder after rebuild
Post by: R.O.R-2.0 on October 10, 2011, 08:40:14 am
There is no way to describe how hard I laughed after reading this...  Karma indeed because I was kind of being a smart ass when I originally posted about your "stash" being in the intake runner..  :P   Glad you got to the bottom of it anyhow..  And for some positive thinking, imagine how much that sock would have cost had it got sucked in there a bit further!  You should see what the yellow pages does when sucked in to a runaway 671 Detroit...

i imagine the blower housing explodes?
Title: Re: dead cylinder after rebuild
Post by: 92EcoDiesel Jetta on October 10, 2011, 11:52:40 am
There is no way to describe how hard I laughed after reading this...  Karma indeed because I was kind of being a smart ass when I originally posted about your "stash" being in the intake runner..  :P   Glad you got to the bottom of it anyhow..  And for some positive thinking, imagine how much that sock would have cost had it got sucked in there a bit further!  You should see what the yellow pages does when sucked in to a runaway 671 Detroit...

i imagine the blower housing explodes?

You mean turbo housing? If the sock was at the inlet of the turbo, it would have affected all cylinders equally, not just #2. That's why I think the sock was at the output side of the turbo.
Title: Re: dead cylinder after rebuild
Post by: J Z on October 10, 2011, 12:04:39 pm
In small letters on the the sock one can read .. Belongs to Mr. Murphy...
Title: Re: dead cylinder after rebuild
Post by: fatmobile on October 11, 2011, 02:20:17 am
I left a rag in before the turbo and forgot to remove it before starting.
 It ran like hell, couldn't figure it out for awhile.

 I feel real lucky it was a fat enough rag to get stuck before making it to the turbo.
Title: Re: dead cylinder after rebuild
Post by: R.O.R-2.0 on October 11, 2011, 07:19:35 am
There is no way to describe how hard I laughed after reading this...  Karma indeed because I was kind of being a smart ass when I originally posted about your "stash" being in the intake runner..  :P   Glad you got to the bottom of it anyhow..  And for some positive thinking, imagine how much that sock would have cost had it got sucked in there a bit further!  You should see what the yellow pages does when sucked in to a runaway 671 Detroit...

i imagine the blower housing explodes?

You mean turbo housing? If the sock was at the inlet of the turbo, it would have affected all cylinders equally, not just #2. That's why I think the sock was at the output side of the turbo.

i was referring to the 6-71 detroit that Brett was talking about that sucked up a phone book..

every detroit diesel (real ones atleast) on the planet has a SUPERCHARGER.. its a requirement for it to run, since the engine has no native vacuum..

and being that the blower is the first part of the intake, thats the first place thats gonna get destroyed by the phone book..
Title: Re: dead cylinder after rebuild
Post by: maxfax on October 11, 2011, 10:12:34 pm
Not saying the blower wasn't damaged, but it managed to do a pretty good job of shredding paper..  It didn;t suck the whole phone book in, just a big chunk out of the center of it..  The book looked like it had a huge exit wound... There was paper all though that engine..  Valves were jammed open, ports were plugged up.. Some even made it to the muffler.. 
Title: Re: dead cylinder after rebuild
Post by: R.O.R-2.0 on October 12, 2011, 04:49:54 pm
wow, thats awesome.. i take it that motor was going for a run-away?
Title: Re: dead cylinder after rebuild
Post by: maxfax on October 12, 2011, 07:23:45 pm
That was the story..  This was back in college..  I never took any of the diesel courses, but the engine lab had both the diesel and gasser engines in it..  The students tore the engine apart and put it back together, and fired it for the first time.. They revved it up and it never came back down.. I guess the first thing in reach to throw over the intake was the Yellow Pages..  It stopped at any rate...