Camshaft cover defect causing rocker-arm breakage (P1302)? - Page 7 - LotusTalk

LBC111 · 01-11-2008, 06:22 PM

Damn.. Thank for all the great detective work guys. I might call my mech and have him pull the cover while it's in the shop.

ZAMMY1 · 01-11-2008, 06:58 PM

similar shims to alfas, maseratis, et al.
buy the exact size or buy a few thicker sizes and grind your own on site.
standard fare.
sam

MikeW · 01-11-2008, 08:47 PM

As far as the oil feed orifice for the tube, a 5/64 drill (.078) fits a tad loose, I'd guess it's .080 or close. Someone said the holes punched in the tube are .051...was that right? Then the some of the are of all the holes is 3 times what the main orifice is. I did some math based on the .051 figure. I ran short on small drills to measure.

The tube is darned close to the base circle, I forgot the numbers I posted. Just for finals, I'll put some clay on a lobe and see where the tube sits as far as cam centerline. It's about 3/8 " off center though.

I checked my lash. By the way, the original manual had a procedure that called for checking at the lash cap on the valve stem. It didn't work and I spent a lot of time wondering how it ever could. I found a service bulletin that had an entirely different method, just insert a feeler through the roller on the small lobe.

Specs: .0039-.0063" intake (.10-.16 mm) Cold
.0094-.0118 ex" ex. (.24-.30mm)

It might be nice to have fractional size feelers, anyway my
intakes were:

cyl 1 .004, #2 .006, #3 .005, #4 .005

ex. #1 .010, #2 .010, #3 .011, #..010

The rockers tip can only contact 1 valve during this procedure,unless both are shimmed dead nuts perfectly to contact both tips. There was a difference of .002 on cyl 1, the rest were within .001 I just checked the intakes, when you try the exhaust, you'll see why. Trunk lid makes it a chore+. Wait until you're in a good mood.

There is a SST tool to depress the springs and allow shim replacement.
The first design of the tool had bugs apparently. There's a TSB about it and
a fix or a 2nd design.

My thoughts. Still why cylinder 3 or 2 or whatever? If that's for real, well...
consider this: All the rockers are the same, in other words, the same batch, there's nothing different about a #3 vs a #1,2 0r 4. So if you're DEFINITELY
dealing with specific cylinders, it's not the rocker. Time will tell if the problem is indeed cylinder specific.

If there was low oil pressure, the orifice at the end of the tube would get less oil. That's cylinder #1.

No one has checked the cam for heat treat. I do not know the procedure for
this, likely it's induction hardening. I think I read that. Why someone would
do an ok job on some lobes but not other is hard to guess. However, there could still be a reason. You'd be surprised what can go occur.

Even specific valve springs allowing valve float vs others is harder to believe.
Again, they're all the same, not cylinder specific.

At this point, I haven't found reasons for this problem to be cylinder specific.
I'm not saying it isn't. You'll need more supporting evidence though.
Then you'll have a job figuring why it is.

It would be easier to find a cause if it wasn't cylinder specific. For instance,
valve float. The rockers have an area that's the thinnest where the force is the highest. I certainly see why they specifically in that area. Not a biggie to understand.

By the way, there's no procedure for dealing with lash for the big cam. The slipper is spring loaded and rides on the lobe at all times. When not engaged for lift, the slipper and it's perch compress their spring when the ramp on the lobe comes up. So it doesn't do anything as far as the rocker movement or valve is concerned. I hate to say that Toyota/Yamaha has this all figured out, that it's perfect and it takes care of itself. Without having it activated for lift so it can be studied, it gives the impression that the valve would never closes completely and that ain't so. Maybe I'll figure a way to pressurize one of my new ones with air and study it some more.

Just for a quiet Sunday, I'll flow the oil tube with Safety Clean from a parts washer. There won't be anything mentioning. If there is, I will. And I'll even do it tube side down and the proper angle to simulate the head angle.

turbophil · 01-11-2008, 08:52 PM

Quote:

Originally Posted by Jack

Could be the cause -- I doubt it's a defective cam cover oil shower.

Phil, you've got to stop talking to Frank.

Ha, you obviously need to do the same!

That damn Frank ratted me out again! That 'ol foul mouthed sailor has a point every once in a while (I know you're reading this Frank)

.........

Also ... I try not to relate my turbo buick experience any more often than I have to, but between the two---there may be something to the lash issue...

More to be discovered in due time, I'm sure...

Best,

Phil

insane · 01-12-2008, 05:45 AM

Quote:

Originally Posted by MikeW

....My thoughts. Still why cylinder 3 or 2 or whatever? If that's for real, well...
consider this: All the rockers are the same, in other words, the same batch, there's nothing different about a #3 vs a #1,2 0r 4. So if you're DEFINITELY
dealing with specific cylinders, it's not the rocker. Time will tell if the problem is indeed cylinder specific...

Mike, it'll be interesting to see what you turn up. Also, I haven't seen any postings in these forums that didn't involve cylinder #3.

ZAMMY1 · 01-12-2008, 04:10 PM

the holes in the oiling tube on my VC are .055", a number 54 drill just fits.
thanks for the info on the hole in the feed tube.
sam

ZAMMY1 · 01-12-2008, 04:13 PM

MIKEW: i think you mean 5/64" drill on that hole.
best wishes, sam

MikeW · 01-12-2008, 08:42 PM

Quote:

Originally Posted by ZAMMY1

MIKEW: i think you mean 5/64" drill on that hole.
best wishes, sam

Yep, I tried to proof read everything but blew it. It's just over 5/64"

AlanS · 01-14-2008, 07:03 AM

Quote:

Originally Posted by insane

Mike, it'll be interesting to see what you turn up. Also, I haven't seen any postings in these forums that didn't involve cylinder #3.

I've mentioned this before but my cam wear was not lilmited to cylinder #3 (2, 3, and 4 I believe).

carl · 01-14-2008, 07:06 AM

Quote:

Originally Posted by AlanS

I've mentioned this before but my cam wear was not lilmited to cylinder #3 (2, 3, and 4 I believe).

Alan, did they take any pictures? carl

scottyb · 01-14-2008, 08:35 AM

Just for the record, Cylinder 1 is the one closest to the Belt (passenger side) correct?

MikeW · 01-14-2008, 10:46 AM

I flowed my cover yesterday using Safety Klean and a parts washer. The tube was aimed down and angled like the head. One thing I noticed: We pinched off the hose from the parts washer to cut some flow and see what happened.
The holes above the intake lobes stop shooting while the exhaust continue. They're lower so gravity determines that. It's not that significant, just that if you lose oil pressure upstairs, the intakes will lose oil first. I also used some clay and measured that the tube is .500 off the lobe base circle, both tubes locate lengthwise just inboard of the cam centerlines. So the off angle of the holes in the tube are insignificant. However, I would be concerned about the upper end running dry if the oil pump sucked air.

AlanS · 01-15-2008, 03:06 PM

Quote:

Originally Posted by 4carl

Alan, did they take any pictures? carl

Carl, unfortunately not. I saw the camshaft and the broken rocker arm pieces at the dealership before they were supposed to be sent back to England. From my recollection, there was a significant wear in three of the high-lift cams. Actually I really don't know for sure that it was cylinders 2 - 4. One of the end cylinder cams was ok and I've assumed (?) the damage centered on cylinder #3, based on the posts that have come to light. This may be incorrect.

AlanS · 01-15-2008, 03:09 PM

Quote:

Originally Posted by MikeW

I flowed my cover yesterday using Safety Klean and a parts washer. The tube was aimed down and angled like the head. One thing I noticed: We pinched off the hose from the parts washer to cut some flow and see what happened.
The holes above the intake lobes stop shooting while the exhaust continue. They're lower so gravity determines that. It's not that significant, just that if you lose oil pressure upstairs, the intakes will lose oil first. I also used some clay and measured that the tube is .500 off the lobe base circle, both tubes locate lengthwise just inboard of the cam centerlines. So the off angle of the holes in the tube are insignificant. However, I would be concerned about the upper end running dry if the oil pump sucked air.

This raises an interesting question. I know the sample size is still pretty small but has anyone who runs an accusump had the problem?

MikeW · 01-16-2008, 09:21 AM

Something popped into my head this morning. I think anyone who has their cover off should do it. Make sure the oil hole in the tube is actually over the lobe. Having the holes completely miss the lobes is possible. I had checked center to center on the holes and center to center on the lobes with a caliper. That was fine, really dead on. I did the lump of clay trick on a lobe base circle. The imprint showed the oil hole was indeed over the lobe. So iff one's ok, the rest are. At least on mine. Clean the oil off the lobe, get a lump of clay and mold it around 90 degrees or better of the base circle lobe so it stays on. It needs to stick up about 3/4". Put Saran Wrap on top. Put the cover on and seat the cover down. Remove the cover and clay. The Saran Wrap will keep the clay out of the spray bar hole but leave an impression of the hole to compare with the cam.

I don't know how Toyota set up to pierce the holes. Since the angle is off several degrees, I think we need to verify if the holes are over the lobes. Their fixture could have shifted when piercing the holes on the cars with worn cams. Just something that needs verification, especially if you have worn lobes.

Icedog_16 · 01-16-2008, 10:22 AM

Not sure what this is worth, but from what I was told (didn't see; so I can't say for sure considering some of the evasiveness I experienced in my situation) my cam lobe was not really scored. However, what I read into that is that, based on my ECU dump, I am quite sure that I was on 2nd cam much less (5.3 hrs out of 346 total hours) than others who have had the same failure. Ergo, it would be logical conclude that I would have less or no scoring of the cam lobe relative to others, regardless of the lubrication issue.

insane · 01-16-2008, 07:11 PM

Quote:

Originally Posted by Manny

....I've been browsing the celica forums for over 7 years and this has never ever happened...

If someone could show a camshaft cover from a Celica--with the same spray pattern and no cam damage--that would be relevent. I don't think we'll see that, however.

mp3moose · 02-07-2008, 09:21 AM

Update for my car:

CEL was on showing p1302, lotus replaced coils and plugs due to "water damage". Light returned with same code so I am taking it in tomorrow morning. I'll try to sway them towards looking at my cam lobes but more likely they will replace the wires or O2 sensor or something pointless.

I'll post up what happens when I speak with Lotus.

Icedog_16 · 02-07-2008, 10:31 AM

Quote:

Originally Posted by mp3moose

Update for my car:

CEL was on showing p1302, lotus replaced coils and plugs due to "water damage". Light returned with same code so I am taking it in tomorrow morning. I'll try to sway them towards looking at my cam lobes but more likely they will replace the wires or O2 sensor or something pointless.

I'll post up what happens when I speak with Lotus.

They did the same thing with mine. Let me guess - the light came on upon hitting the 2nd cam for a short time; after the repair, mine came on the first time I was at WOT in 3rd. You could always do like I did and show off your skill of prognostication and tell them that they will find a broken rocker arm on the number-three cylinder. The fact that I could tell them the problem before they even got on the car is exactly why I was so vehement in maintaining that there is a problem with these engines or their implementation in these cars as opposed to its use in a Celica.

Please let us know how it goes. Also, get a copy of your ECU dump and post it. When the time is right (preferably after we get more data on your car), I'm going to post information about my experience and try to take this to the next level. To me, the manner in which Lotus has handled some of these failures has been quite similar to what they did with the broken stick shifts and the bad 2nd-gear sychros. They blamed the vehicle owner when, in fact, the design was deficient or insufficient for the expected usage. The only way proper, decisive action was taken was when the NHTSA got involved.

mp3moose · 02-08-2008, 09:43 AM

Just spoke with Marty at Criswell and they are replacing my 4th coil. Last time (about two months ago) they replaced just 3 of them due to "water damage" and now suddenly the fourth one goes bad even though the car has been covered in my garage during that time and only driven 3 times on sunny days.

I couldn't convience him to pull the head off and have a look at the camshaft unfortunately. So, if indeed I have a cam/rocker arm issue it looks like I will be going through the motions of replacing unrelated electrical parts first.

I did some datalogging last night with my Autotap to the check the code and monitor anything unusual while in the second cam. Didn't want to clear the code because I needed the dealer to see it but this weekend I plan to do more and see if I can find anything. I'll compare my results if there are concrete findings.

01-11-2008, 06:22 PM	#121 (permalink)
LBC111 Dan D Join Date: Aug 2005 Location: Long Beach, CA Posts: 1,409	Damn.. Thank for all the great detective work guys. I might call my mech and have him pull the cover while it's in the shop. __________________ 07 Exige S 265: GG, Track Pack, V1, RV Camera, S111 CF roof and splitter, 4.5-lb Voltphreaks battery, 10-lb Von Hep Exhaust, Green filter, 265 crank hp +/-, Volk TE 37 Wheels, RTDbrace, Scroth 6-point ASM harnesses, Innovative Motor Mounts, Saiku Michi Catch Cans. To come: IC fans, headers, and sport cat. 1955 lbs total weight (est w/tank half full) 05 Elise: Storm Titanium, Sport, Touring, Stage II (SOLD) (May '05 - Sept '06)

01-11-2008, 08:47 PM	#123 (permalink)
MikeW Registered User Join Date: Feb 2006 Posts: 1,372	As far as the oil feed orifice for the tube, a 5/64 drill (.078) fits a tad loose, I'd guess it's .080 or close. Someone said the holes punched in the tube are .051...was that right? Then the some of the are of all the holes is 3 times what the main orifice is. I did some math based on the .051 figure. I ran short on small drills to measure. The tube is darned close to the base circle, I forgot the numbers I posted. Just for finals, I'll put some clay on a lobe and see where the tube sits as far as cam centerline. It's about 3/8 " off center though. I checked my lash. By the way, the original manual had a procedure that called for checking at the lash cap on the valve stem. It didn't work and I spent a lot of time wondering how it ever could. I found a service bulletin that had an entirely different method, just insert a feeler through the roller on the small lobe. Specs: .0039-.0063" intake (.10-.16 mm) Cold .0094-.0118 ex" ex. (.24-.30mm) It might be nice to have fractional size feelers, anyway my intakes were: cyl 1 .004, #2 .006, #3 .005, #4 .005 ex. #1 .010, #2 .010, #3 .011, #..010 The rockers tip can only contact 1 valve during this procedure,unless both are shimmed dead nuts perfectly to contact both tips. There was a difference of .002 on cyl 1, the rest were within .001 I just checked the intakes, when you try the exhaust, you'll see why. Trunk lid makes it a chore+. Wait until you're in a good mood. There is a SST tool to depress the springs and allow shim replacement. The first design of the tool had bugs apparently. There's a TSB about it and a fix or a 2nd design. My thoughts. Still why cylinder 3 or 2 or whatever? If that's for real, well... consider this: All the rockers are the same, in other words, the same batch, there's nothing different about a #3 vs a #1,2 0r 4. So if you're DEFINITELY dealing with specific cylinders, it's not the rocker. Time will tell if the problem is indeed cylinder specific. If there was low oil pressure, the orifice at the end of the tube would get less oil. That's cylinder #1. No one has checked the cam for heat treat. I do not know the procedure for this, likely it's induction hardening. I think I read that. Why someone would do an ok job on some lobes but not other is hard to guess. However, there could still be a reason. You'd be surprised what can go occur. Even specific valve springs allowing valve float vs others is harder to believe. Again, they're all the same, not cylinder specific. At this point, I haven't found reasons for this problem to be cylinder specific. I'm not saying it isn't. You'll need more supporting evidence though. Then you'll have a job figuring why it is. It would be easier to find a cause if it wasn't cylinder specific. For instance, valve float. The rockers have an area that's the thinnest where the force is the highest. I certainly see why they specifically in that area. Not a biggie to understand. By the way, there's no procedure for dealing with lash for the big cam. The slipper is spring loaded and rides on the lobe at all times. When not engaged for lift, the slipper and it's perch compress their spring when the ramp on the lobe comes up. So it doesn't do anything as far as the rocker movement or valve is concerned. I hate to say that Toyota/Yamaha has this all figured out, that it's perfect and it takes care of itself. Without having it activated for lift so it can be studied, it gives the impression that the valve would never closes completely and that ain't so. Maybe I'll figure a way to pressurize one of my new ones with air and study it some more. Just for a quiet Sunday, I'll flow the oil tube with Safety Clean from a parts washer. There won't be anything mentioning. If there is, I will. And I'll even do it tube side down and the proper angle to simulate the head angle. Last edited by MikeW : 01-12-2008 at 08:43 PM. Reason: corrected measurement

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01-11-2008, 06:58 PM	#122 (permalink)
ZAMMY1 ZAMMY Join Date: Jan 2007 Location: washington, pa, (near PGH.) Posts: 1,557	similar shims to alfas, maseratis, et al. buy the exact size or buy a few thicker sizes and grind your own on site. standard fare. sam

01-12-2008, 04:10 PM	#126 (permalink)
ZAMMY1 ZAMMY Join Date: Jan 2007 Location: washington, pa, (near PGH.) Posts: 1,557	the holes in the oiling tube on my VC are .055", a number 54 drill just fits. thanks for the info on the hole in the feed tube. sam

01-12-2008, 04:13 PM	#127 (permalink)
ZAMMY1 ZAMMY Join Date: Jan 2007 Location: washington, pa, (near PGH.) Posts: 1,557	MIKEW: i think you mean 5/64" drill on that hole. best wishes, sam

01-14-2008, 08:35 AM	#131 (permalink)
scottyb Registered User Join Date: Dec 2004 Posts: 3,683	Just for the record, Cylinder 1 is the one closest to the Belt (passenger side) correct?

01-14-2008, 10:46 AM	#132 (permalink)
MikeW Registered User Join Date: Feb 2006 Posts: 1,372	I flowed my cover yesterday using Safety Klean and a parts washer. The tube was aimed down and angled like the head. One thing I noticed: We pinched off the hose from the parts washer to cut some flow and see what happened. The holes above the intake lobes stop shooting while the exhaust continue. They're lower so gravity determines that. It's not that significant, just that if you lose oil pressure upstairs, the intakes will lose oil first. I also used some clay and measured that the tube is .500 off the lobe base circle, both tubes locate lengthwise just inboard of the cam centerlines. So the off angle of the holes in the tube are insignificant. However, I would be concerned about the upper end running dry if the oil pump sucked air.

01-16-2008, 09:21 AM	#135 (permalink)
MikeW Registered User Join Date: Feb 2006 Posts: 1,372	Something popped into my head this morning. I think anyone who has their cover off should do it. Make sure the oil hole in the tube is actually over the lobe. Having the holes completely miss the lobes is possible. I had checked center to center on the holes and center to center on the lobes with a caliper. That was fine, really dead on. I did the lump of clay trick on a lobe base circle. The imprint showed the oil hole was indeed over the lobe. So iff one's ok, the rest are. At least on mine. Clean the oil off the lobe, get a lump of clay and mold it around 90 degrees or better of the base circle lobe so it stays on. It needs to stick up about 3/4". Put Saran Wrap on top. Put the cover on and seat the cover down. Remove the cover and clay. The Saran Wrap will keep the clay out of the spray bar hole but leave an impression of the hole to compare with the cam. I don't know how Toyota set up to pierce the holes. Since the angle is off several degrees, I think we need to verify if the holes are over the lobes. Their fixture could have shifted when piercing the holes on the cars with worn cams. Just something that needs verification, especially if you have worn lobes.

01-16-2008, 10:22 AM	#136 (permalink)
Icedog_16 I drank what?!? Join Date: May 2005 Location: Tampa, FL Posts: 4,214	Not sure what this is worth, but from what I was told (didn't see; so I can't say for sure considering some of the evasiveness I experienced in my situation) my cam lobe was not really scored. However, what I read into that is that, based on my ECU dump, I am quite sure that I was on 2nd cam much less (5.3 hrs out of 346 total hours) than others who have had the same failure. Ergo, it would be logical conclude that I would have less or no scoring of the cam lobe relative to others, regardless of the lubrication issue.

02-07-2008, 09:21 AM	#138 (permalink)
mp3moose Complete Lotus Junkie Join Date: May 2004 Location: Washington DC Posts: 692	Update for my car: CEL was on showing p1302, lotus replaced coils and plugs due to "water damage". Light returned with same code so I am taking it in tomorrow morning. I'll try to sway them towards looking at my cam lobes but more likely they will replace the wires or O2 sensor or something pointless. I'll post up what happens when I speak with Lotus.

02-08-2008, 09:43 AM	#140 (permalink)
mp3moose Complete Lotus Junkie Join Date: May 2004 Location: Washington DC Posts: 692	Just spoke with Marty at Criswell and they are replacing my 4th coil. Last time (about two months ago) they replaced just 3 of them due to "water damage" and now suddenly the fourth one goes bad even though the car has been covered in my garage during that time and only driven 3 times on sunny days. I couldn't convience him to pull the head off and have a look at the camshaft unfortunately. So, if indeed I have a cam/rocker arm issue it looks like I will be going through the motions of replacing unrelated electrical parts first. I did some datalogging last night with my Autotap to the check the code and monitor anything unusual while in the second cam. Didn't want to clear the code because I needed the dealer to see it but this weekend I plan to do more and see if I can find anything. I'll compare my results if there are concrete findings.

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