Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Post Reply
 
LinkBack Thread Tools Display Modes
Old 05-26-2019, 06:32 AM   #1
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Engine Jumped Timing Diagnosis- 2000 Base

Concerns a PROJECT BOXSTER - Couldn’t resist buying a $700 Boxster that wouldn’t start, w/133k miles. Diagnosed by a Porsche Dealer, as cam 1 had jumped timing. NO KNOWN INFORMATION other than that, from the previous owner. Husband died and the wife picked it up from Porsche and sold it after sitting for a year or so.

I brought it home yesterday, washed it, cleaned it up, and put it up on a lift and started to dig in. No metallic particle or plastic piece in the oil sump ( very surprised), and the coolant was clear orange.

Let’s just get this out of the way.....not every engine issue is the IMS. I’m not saying that this isn’t IMS related, BUT, I am not one that chirps IMS as the cause for every issue.

1. What are causes to jump timing that don’t produce any plastic or metallic particles in oil sump or filter?

2. What diagnostic steps/tests would you do, to determine possible failure cause?

I can pull the engine, and am absolutely realistic about potential damage. I have no illusions that there is a real simple fix. But before pulling the engine, I thought I would get the brain trust involved and methodically eliminate causes, if possible.

I do not want to try and crank it over, with the starter.

I know I can buy a replacement engine and throw it in there.

Thanks!!

__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-26-2019, 09:58 AM   #2
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Upon a little closer inspection, I did find a couple of small, hard brown plastic pieces in the oil sump. I didn’t mention before, but someone may have either drained the oil or been into the bottom end before, because only a couple of quarts of oil came out.

Also, I hooked up a reader. The only code that popped up was P0336. Camshaft position sensor error.

I turned the engine over by hand, both side cam shafts rotate.
__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-26-2019, 10:35 AM   #3
Registered User
 
Join Date: Sep 2016
Location: Stow, MA
Posts: 918
Garage
Worn cam chain tensioner pads. The brown bits are pieces off the pads.

If the chain gets loose enough it can skip a tooth. Try turning the engine manually and see if you can get the slots for the cam locking tool to line up. As far as I remember they should both be vertical at the same time. That should give you a clue.
__________________
2004 Boxster S Silver - FUNTOY
2002 Boxster Base Guardsy Red - FUNBOX
1987 Caterham Super 7 1700 Supersprint
2009 Mercedes Benz CLK 350 convertible
1941 Dodge Luxury Liner Coupe
Anker is offline   Reply With Quote
Old 05-26-2019, 11:34 AM   #4
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
I grabbed my endoscope, and tried to take some pictures of the pistons on Bank 1. Not too sure it shows me a whole lot. Maybe more experienced eyes can tell me something. I have a feeling that I can only see the center portion of each piston, and not the whole thing.



__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-26-2019, 02:14 PM   #5
Porsche "Purist"
 
Paul's Avatar
 
Join Date: Aug 2003
Location: Wisconsin
Posts: 2,123
Garage
My 01 base slipped timing at 89,000. IMS was fine. LN bought the motor said it was a stretched timing chain. I abused the motor it had about 30,000 stage one over revs.
__________________
1998 Boxster with 7.8 DME, 2005 3.6 liter/325 hp, Variocam Plus, 996 Instrument panel
2001 Boxster original owner. I installed used motor at 89k.
1987 924S. 2002 996TT. PST-2
Owned and repaired Porsches since 1974. Porsche: It's not driving, it's therapy.
Paul is offline   Reply With Quote
Old 05-26-2019, 05:44 PM   #6
Who's askin'?
 
maytag's Avatar
 
Join Date: Mar 2018
Location: Utah
Posts: 2,446
First thing I would do is ignore what they've told you about the car. Do your own diagnostics.
IE: how do you know the cam has jumped? CHECK IT. easy enough to check your cam timing on this motor. Anker already pointed you in the right direction.

Be sure you're chasing the right problem, is all I'm saying.

Remember that it's quite possible that somebody already dumped the oil & changed the filter, so don't assume there either.



Sent from my SM-G970U using Tapatalk
maytag is offline   Reply With Quote
Old 05-27-2019, 02:43 PM   #7
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Quote:
Originally Posted by maytag View Post
First thing I would do is ignore what they've told you about the car. Do your own diagnostics.
IE: how do you know the cam has jumped? CHECK IT. easy enough to check your cam timing on this motor. Anker already pointed you in the right direction.

Be sure you're chasing the right problem, is all I'm saying.

Remember that it's quite possible that somebody already dumped the oil & changed the filter, so don't assume there either.



Sent from my SM-G970U using Tapatalk
Absolutely 100% agree. I didn’t get a lot of information. Just that it died while the daughter was driving (no specifics) and that the Porsche dealership diagnosed that the bank 1 timing was off. I received the report.

I locked the engine at TDC with the “special locking tool” and used my borescope to to take a couple of pictures. It would appear that Bank 1 is indeed off, a little. I didn’t have enough room to get the locking tool installed, it you can clearly see the exhaust cam is rotated counter clockwise a little bit, just before being completely vertical.

For some reason I can’t attach pictures via my IPad or IPhone. I’ll try later with my PC.
__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-27-2019, 03:43 PM   #8
Registered User
 
Join Date: Oct 2018
Location: North Cali
Posts: 745
Garage
Quote:
Originally Posted by Anker View Post
Worn cam chain tensioner pads. The brown bits are pieces off the pads.

If the chain gets loose enough it can skip a tooth. Try turning the engine manually and see if you can get the slots for the cam locking tool to line up. As far as I remember they should both be vertical at the same time. That should give you a clue.
I agree. I had the same issue with mine, the chain pads wore out and one completely slipped out of the way and got the chain loose. Take a look at my show&tell thread, that may give you an idea how deeply you will have to dig into the engine. I think it`s possible to fix it without pulling the engine out, it`s not an easy job though with the engine in place.
Homeoboxter is offline   Reply With Quote
Old 05-28-2019, 09:32 AM   #9
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
I was able to upload the pictures of the timing of Bank 1 via my PC. I also pulled the spark plug from Bank 1, when I used the borescope to try and inspect the cylinders.

__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-28-2019, 09:35 AM   #10
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Quote:
Originally Posted by Homeoboxter View Post
I agree. I had the same issue with mine, the chain pads wore out and one completely slipped out of the way and got the chain loose. Take a look at my show&tell thread, that may give you an idea how deeply you will have to dig into the engine. I think it`s possible to fix it without pulling the engine out, it`s not an easy job though with the engine in place.
Thanks. I am curious, when the chain pad slipped out of the way and the chain loosened, did it do damage to your engine? Did you get a CEL or anything?

I will search for your thread and check it out. Thanks for the feedback.
__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-29-2019, 01:18 PM   #11
Registered User
 
Join Date: Oct 2018
Location: North Cali
Posts: 745
Garage
Quote:
Originally Posted by TNT79Bronco View Post
Thanks. I am curious, when the chain pad slipped out of the way and the chain loosened, did it do damage to your engine? Did you get a CEL or anything?

I will search for your thread and check it out. Thanks for the feedback.
I bought the car as non-op, I`ve never seen it running. The valves clearly made contact with the pistons, but nothing broke or got damaged.
Homeoboxter is offline   Reply With Quote
Old 05-29-2019, 03:24 PM   #12
Registered User
 
Join Date: Aug 2018
Location: Woodland Wa
Posts: 1,291
With a cam out of time (and you have visual evidence of that) I would want to check the valve train to make sure nothing was bent or damaged..:eek your endoscope pictures may be showing some valve piston contact. hard to tell. Pistons look undamaged.
blue62 is offline   Reply With Quote
Old 05-30-2019, 01:50 PM   #13
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Quote:
Originally Posted by blue62 View Post
With a cam out of time (and you have visual evidence of that) I would want to check the valve train to make sure nothing was bent or damaged..:eek your endoscope pictures may be showing some valve piston contact. hard to tell. Pistons look undamaged.
Yeah....thanks. I kind of suspected that, from the way it looks....BUT.....hopeful. I am in the process of pulling the transmission and then the engine. I will dig into the engine and see what the status is, and then post some more pictures.

It would be waaaaaay overly optimistic of me to hope that there wasn't any damage to the heads or the valves.
__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-30-2019, 01:51 PM   #14
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Quote:
Originally Posted by Homeoboxter View Post
I bought the car as non-op, I`ve never seen it running. The valves clearly made contact with the pistons, but nothing broke or got damaged.
Sounds like we need to get that bad boy running!!!! I see you are in San Jose. I am in San Ramon!
__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-30-2019, 02:07 PM   #15
Registered User
 
Join Date: Aug 2018
Location: Woodland Wa
Posts: 1,291
Thumbs up

Bronco
Please post pictures of what you find, myself as well as many others will be interested in what your follow up finds.
Good luck with it, you may get by with minor damage.
blue62 is offline   Reply With Quote
Old 05-30-2019, 06:13 PM   #16
Registered User
 
Join Date: Oct 2018
Location: North Cali
Posts: 745
Garage
Quote:
Originally Posted by TNT79Bronco View Post
Yeah....thanks. I kind of suspected that, from the way it looks....BUT.....hopeful. I am in the process of pulling the transmission and then the engine. I will dig into the engine and see what the status is, and then post some more pictures.

It would be waaaaaay overly optimistic of me to hope that there wasn't any damage to the heads or the valves.
It`s entirely possible. You mentioned the crank can spin around freely.
Homeoboxter is offline   Reply With Quote
Old 05-30-2019, 06:16 PM   #17
Registered User
 
Join Date: Oct 2018
Location: North Cali
Posts: 745
Garage
Quote:
Originally Posted by TNT79Bronco View Post
Sounds like we need to get that bad boy running!!!! I see you are in San Jose. I am in San Ramon!
Oh, great! Feel free to stop by if you wanna look into the engine in person before you pull it apart. Mine is still in bits and bolts...
Homeoboxter is offline   Reply With Quote
Old 05-30-2019, 09:09 PM   #18
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Quote:
Originally Posted by Homeoboxter View Post
Oh, great! Feel free to stop by if you wanna look into the engine in person before you pull it apart. Mine is still in bits and bolts...
Thanks! I have had the good fortune of being able to attend Jake Raby’s engine assembly class in Georgia. We started off by disassembling two engines and determing the cause of failure. We then assembled a complete engine, from the ground up over the next couple of days. Very cool class.
__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-31-2019, 12:18 PM   #19
Registered User
 
Join Date: Dec 2009
Location: Orange County, CA
Posts: 1,843
Quote:
Originally Posted by TNT79Bronco View Post
Thanks! I have had the good fortune of being able to attend Jake Raby’s engine assembly class in Georgia. We started off by disassembling two engines and determing the cause of failure. We then assembled a complete engine, from the ground up over the next couple of days. Very cool class.
+ 1

Very cool indeed..!
Gilles is offline   Reply With Quote
Old 05-31-2019, 12:59 PM   #20
Registered User
 
Join Date: Oct 2018
Location: North Cali
Posts: 745
Garage
Quote:
Originally Posted by TNT79Bronco View Post
Thanks! I have had the good fortune of being able to attend Jake Raby’s engine assembly class in Georgia. We started off by disassembling two engines and determing the cause of failure. We then assembled a complete engine, from the ground up over the next couple of days. Very cool class.
Nice! What`s required to be able to attend?

Homeoboxter is offline   Reply With Quote
Post Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 01:53 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page