Camshaft timing/Durmetric readings/errors
04-29-2010, 04:00 PM
#16
You may already know this -Page 53 of the Porsche Diagnostic Manual provides the DME Setpoints .Camshaft deviation is + or- 6 degrees . Not sure what to conclude from that -except it's a 12 degree swing and that's acceptable .
Dave
Dave
04-29-2010, 06:43 PM
#17
Racer
Join Date: Jun 2004
Location: Brandon FL
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Thanks for everyone comments and thoughts.
rb101 - That is interesting on the Crank/IMS tensioner. This is one of the questions I have been trying to figure out. The 1-3 tensioner has not really been changed, and the change to the 4-6 tensioner is really just a change to the head so that instead of using a sprocket you use an allen wrench. However the Cranck/IMS tensioner has been totally redesigned, and now instead of a closed piston it appears to have an exposed spring. This change was made when the engines went from the VarioCam 3.4 series, which are 5 chain engines, to the VarioCamPlus engines, which are three chain engines. And apparently the Porsche Tech bulletins say to used the old style tensioners. However if you look at the LN engineering site for the IMS bearing upgrade, where they recommend that you replace the tensioners, they say to use the new styles all the way around. And I spoke to Charles at LN the other day and he says that they are using the new style Crank/IMS tensioner in their 3.4 engines that they race. Still trying to figure this out but your comments are appreciated. Maybe I will email Jake RAby and see if he has some input.
rb101 - That is interesting on the Crank/IMS tensioner. This is one of the questions I have been trying to figure out. The 1-3 tensioner has not really been changed, and the change to the 4-6 tensioner is really just a change to the head so that instead of using a sprocket you use an allen wrench. However the Cranck/IMS tensioner has been totally redesigned, and now instead of a closed piston it appears to have an exposed spring. This change was made when the engines went from the VarioCam 3.4 series, which are 5 chain engines, to the VarioCamPlus engines, which are three chain engines. And apparently the Porsche Tech bulletins say to used the old style tensioners. However if you look at the LN engineering site for the IMS bearing upgrade, where they recommend that you replace the tensioners, they say to use the new styles all the way around. And I spoke to Charles at LN the other day and he says that they are using the new style Crank/IMS tensioner in their 3.4 engines that they race. Still trying to figure this out but your comments are appreciated. Maybe I will email Jake RAby and see if he has some input.
Rick
99 996C4
87 944S
Last edited by rb101; 06-09-2010 at 08:52 PM.
04-30-2010, 12:26 AM
#18
Drifting
Thread Starter
That doesn't look good! Charles from LN told me he was running the new style tensioner in a 3.4, but maybe his was after the change to the new style chain, which took place mid 2000 I think. Mine is a 2000, but was actually made in late 99 and has the old style chain. I emailed Jake RAby to see if he can give some clarification but your picture sure look convincing.
04-28-2014, 10:11 PM
#19
Drifting
Thread Starter
I thought I would resurrect this thread and give an update on the cam deviations I have had since I fixed the intermix on my car. Looking back to the first post I had the following deviations showing on my Durametric.
Camshaft position 1 deviation -12.15
Camshaft position 2 deviation -02.45
I set the cam timing by eye with my shade tree method. Visually the slots on the end of the exhaust cam seemed to line up with the seam between the head and the cam cover, and looked good with a straight edge. I was unsure if there was a bent tab for the hall effect sensor on the intake cam, if I had missed a link on the cam to cam chain or what. I did not drop the engine and have 5 years and 30,000+ miles since with the engine seeming to run well.
So a week or so ago I checked the deviations again and they were still off by approx. the same amount. Having acquired a tool set with an aftermarket version of the Porsche cam timing tool I decided that I wanted to find out if the problem was real. Well the Porsche tools will not fit with the engine in the car, and I wanted to do some other work so i decided to drop the engine and see what was going on.
Even with the engine out of the car it was still difficult to get the tool on the 1-3 head as an oxygen sensor and the engine mount frame were still in the way. By loosening some bolts, etc. I did manage to get the tool in place and here is a picture of what I found.
https://rennlist.com/forums/attachme...1&d=1398731776
You can see that the cam was in fact off by several degrees. Remember that 12 degrees at the crank, which is what the Durametric reads, is only 6 degrees at the cam. This is hard to see visually without the tool, but with the tool in place the deviation is pretty obvious. The extension of the arm of the tool from the exhaust cam to the intake cam makes the deviation more apparent.
By the way I did find that with the eBay version of the tool, which is what I have, the part that fits into the exhaust cam slot was put together 180 degrees out of place. I guess you get what you pay for but it was easy to turn the part 180 degree (two set screws) and then it worked fine.
I reset the timing on the 1-3 cams and also checked the 4-6 side, which was off on the Durametric by 2 degrees and it was just slightly off with the tool. Reset that to.
So if you are setting the cam timing, and if you want to do it with the engine in the car, it might be best to get the LN Engineering cam locking tool that is part of their bearing installation tool kit or to get the ZDmak cam timing tool. I think that either of these tools would fit wit the engine in the car. They do work a little differently than the Porsche tool. With the Porsche style tool you lock the engine at TDC, then install the tool with the one end in the exhaust cam, loosen the bolts on the exhaust cam sprocket and use the tool to rotate the cams to the correct position, then tighten the bolts on the sprocket. With the other tools you would have to lock the cams in place, then loosen the bolt on the exhaust cam sprocket and rotate the crank to TDC.
I am anxious to see what the Durametric shows for deviations now and if the engine runs smoother and stronger. However that is going to have to wait for a few days. I am going to do a ceramic IMS bearing and the new Direct Oil Feed from Tuners Motor Sports/Pedro's Garage and address a few oil leaks before the engine goes back in the car. Still waiting for some parts for this.
Camshaft position 1 deviation -12.15
Camshaft position 2 deviation -02.45
I set the cam timing by eye with my shade tree method. Visually the slots on the end of the exhaust cam seemed to line up with the seam between the head and the cam cover, and looked good with a straight edge. I was unsure if there was a bent tab for the hall effect sensor on the intake cam, if I had missed a link on the cam to cam chain or what. I did not drop the engine and have 5 years and 30,000+ miles since with the engine seeming to run well.
So a week or so ago I checked the deviations again and they were still off by approx. the same amount. Having acquired a tool set with an aftermarket version of the Porsche cam timing tool I decided that I wanted to find out if the problem was real. Well the Porsche tools will not fit with the engine in the car, and I wanted to do some other work so i decided to drop the engine and see what was going on.
Even with the engine out of the car it was still difficult to get the tool on the 1-3 head as an oxygen sensor and the engine mount frame were still in the way. By loosening some bolts, etc. I did manage to get the tool in place and here is a picture of what I found.
https://rennlist.com/forums/attachme...1&d=1398731776
You can see that the cam was in fact off by several degrees. Remember that 12 degrees at the crank, which is what the Durametric reads, is only 6 degrees at the cam. This is hard to see visually without the tool, but with the tool in place the deviation is pretty obvious. The extension of the arm of the tool from the exhaust cam to the intake cam makes the deviation more apparent.
By the way I did find that with the eBay version of the tool, which is what I have, the part that fits into the exhaust cam slot was put together 180 degrees out of place. I guess you get what you pay for but it was easy to turn the part 180 degree (two set screws) and then it worked fine.
I reset the timing on the 1-3 cams and also checked the 4-6 side, which was off on the Durametric by 2 degrees and it was just slightly off with the tool. Reset that to.
So if you are setting the cam timing, and if you want to do it with the engine in the car, it might be best to get the LN Engineering cam locking tool that is part of their bearing installation tool kit or to get the ZDmak cam timing tool. I think that either of these tools would fit wit the engine in the car. They do work a little differently than the Porsche tool. With the Porsche style tool you lock the engine at TDC, then install the tool with the one end in the exhaust cam, loosen the bolts on the exhaust cam sprocket and use the tool to rotate the cams to the correct position, then tighten the bolts on the sprocket. With the other tools you would have to lock the cams in place, then loosen the bolt on the exhaust cam sprocket and rotate the crank to TDC.
I am anxious to see what the Durametric shows for deviations now and if the engine runs smoother and stronger. However that is going to have to wait for a few days. I am going to do a ceramic IMS bearing and the new Direct Oil Feed from Tuners Motor Sports/Pedro's Garage and address a few oil leaks before the engine goes back in the car. Still waiting for some parts for this.
03-26-2017, 02:00 PM
#21
Drifting
I sent a Message to Doug to ask about the outcome.
Note his kind warning about the Ebay tool being 180 degrees off.
I also wonder if fitting to new style 1-3 Timing Chain Tensioner helped solve the problems?
It is noteworthy that the Porsche OEM tool kit (also sold by Baum # B9612KPLUS) comes with no Instructions for use. They don't even identify the various tools in the kit.See the EWK site if you want the specific part numbers with a photo. The tool shown in Post 19 #9612)above is a good example The black polygon shaped part at the top of the photo shows how the tool can show if the exhaust cam slot is slightly off. The black polygon slides in & out and is retained by set screw with a 3mm Allen hex head.Unfortunately this tool is too large to fit with the engine in place.
Most of the Baum tools are un-useable with the engine in the car. They are just too large and clumsy. You may also have to grind off corners that prevent full engagement of the tools.
The TDC lock pins are a good example - far too large and an 8mm or 5/16" bolt or drill bit works just as well. An awl helps you locate the TDC hole when you approach TDC. That is not supplied but a 10d common nail works well enough.
No wonder they asked Jake Raby for help. The LN tools work great -of course.Jake wrote:
"The allocation (lobe separation) of the intake/ exhaust cams is set by the chains and the amount of teeth between the dots. For your engine their should be two discolored chain links that are 7 teeth apart that will align with these dots.
After the cams are allocated to each other the camshaft alignment tool then indexes the exhaust cam to the crankshaft after the crank is locked into position.
I (Jake, not me!)am in the process of writing some instructions for the folks at Baum for their tool kits as I have assisted them with the fine tuning of these. I also plan to do an instructional DVD on this soon"
https://rennlist.com/forums/996-foru...ol-9612-a.html
Note his kind warning about the Ebay tool being 180 degrees off.
I also wonder if fitting to new style 1-3 Timing Chain Tensioner helped solve the problems?
It is noteworthy that the Porsche OEM tool kit (also sold by Baum # B9612KPLUS) comes with no Instructions for use. They don't even identify the various tools in the kit.See the EWK site if you want the specific part numbers with a photo. The tool shown in Post 19 #9612)above is a good example The black polygon shaped part at the top of the photo shows how the tool can show if the exhaust cam slot is slightly off. The black polygon slides in & out and is retained by set screw with a 3mm Allen hex head.Unfortunately this tool is too large to fit with the engine in place.
Most of the Baum tools are un-useable with the engine in the car. They are just too large and clumsy. You may also have to grind off corners that prevent full engagement of the tools.
The TDC lock pins are a good example - far too large and an 8mm or 5/16" bolt or drill bit works just as well. An awl helps you locate the TDC hole when you approach TDC. That is not supplied but a 10d common nail works well enough.
No wonder they asked Jake Raby for help. The LN tools work great -of course.Jake wrote:
"The allocation (lobe separation) of the intake/ exhaust cams is set by the chains and the amount of teeth between the dots. For your engine their should be two discolored chain links that are 7 teeth apart that will align with these dots.
After the cams are allocated to each other the camshaft alignment tool then indexes the exhaust cam to the crankshaft after the crank is locked into position.
I (Jake, not me!)am in the process of writing some instructions for the folks at Baum for their tool kits as I have assisted them with the fine tuning of these. I also plan to do an instructional DVD on this soon"
https://rennlist.com/forums/996-foru...ol-9612-a.html
Last edited by Schnell Gelb; 03-26-2017 at 08:10 PM.
03-26-2017, 05:31 PM
#22
Drifting
Thread Starter
Been a long time since I did this. I did replace all three tensioners and put in the Direct Oil Feed bearing. I forget if I ran the Durometric and what the read out was. I will have to run it again but mr friend has it right now to clear a code off his engine.
