Oil Pan Gasket Replacement Success
07-02-2011, 09:32 AM
#1
Burning Brakes
Thread Starter
Oil Pan Gasket Replacement Success
Having removed the oil pan in my 968 to replace the leaking pan gasket and to inspect the oil pickup tube and rod bearings, I did a search of the data base in order to find if there were any issues with replacing the oil pan gasket.
And, man was there ever a list of issues! Having read it all and then reviewing what is written in the OEM Shop Manual and on Clarks Garage, I came to a number of conclusions about how I would do the job.
First, after cleaning up all the old parts, and before attempting to install the gasket on the pan, take the oil pan (without gasket) and play around with getting it into place on the engine. You have to lift in place while orienting it so that the oil pickup tube (and suction screen) slide into the oil baffle mounted in the bottom of the pan. Not really difficult, but you need to see how to "coax" the pan into place without disturbing the gasket.
Then there are two major issues with this gasket. The first issue apparently is a tendency for the gasket to creep out of position as the pan bolts are tightened since it is very lightly torqued. The second issue is installation cleanliness. The gasket is an elaborate geometry; but there have been issues with contamination from a residual of parting agent on the gasket remaining from its manufacture. And, since the gasket is a little bit complicated, there is a tendency for the gasket to move around during installation..
So, I attacked cleanliness first. I wiped down the rubber gasket with alcohol to remove any type of contamination. Then I wiped down the oil pan flange and the machined mating surface on the engine. I was careful to remove all remnants of the old gasket or materials that were used to hold it in place, without mechanically attempting to smooth out the mating surfaces. To do this I used a Scotchbrite pad and some acetone as a solvent. Worked great.
I also concluded that one should not attempt to sand down the mating surfaces on the pan and the engine. There is some micro roughness left by machining marks on the block. This minimal amount of roughness may be intentional and needed to hold the lightly torqued pan gasket in place.
Then I used a minimal amount of gasket adhesive ONLY in the four corners of the oil pan (as discussed both in the shop manual and on Clarks Garage). Please note that I used a gasket adhesive, and NOT a gasket sealant. I thinly spread the adhesive on the four corners of both the gasket and the mating area of the pan. When I pressed the gasket into place, it was held there by the adhesive. Also, I inserted the (4) long pan screws in the (4) corners of the pan. This helped to pin the corners of the gasket down during installation while also allowing the long bolts to be held in place so that during installation, while holding the pan in place with one hand, you would have easy access to the already inserted bolts. This also worked very well. There was enough of a misalignment between the holes in the gasket and the pan to just squeeze the bolts, thus holding them in place. If that does not work, then use a little bit of duct tape to hold the bolts into the pan (I did this with one of the four bolts).
I also followed the advice of others and tied down every other bolt hole in the gasket to the pan using dental floss. Once the pan is in place, you can cut the dental floss free with a razor blade (my choice). This worked like a champ.
Also, do not attempt to install the oil level sender in the pan until AFTER the pan has been installed since the level sender interferes with the oil pump suction pipe. Ask me how I know this!!
The bottom line is that it took me all of 20 minutes to prep the engine and pan and to trial fit the pan. Once I found the angles needed to slip the pan into place, I installed the gasket on the pan and aligned the pan and then slid it into place. Once installed, I was able to hand thread the four corner bolts and then the remaining bolts into place while removing the dental floss with a razor blade.
One concern that I had was that the gasket "arch" on both ends of the gasket slide in the grooves on the engine block as the pan is put into place. You want to visually confirm this. While visual confirmation is possible at the front of the oil pan, you can not see up into the area on the rear of the oil pan once the pan is slid into place. In fact, there is a gap between the rear of the oil pan and the flywheel housing that is only about 3/8"wide, so you really can't even get a finger up into the area to "feel" that the gasket is evenly inserted into the groove. I tried getting a mirror up in the area to see, but that was not possible either. So, to confirm that the gasket was laid into the groove evenly, I made a tool out of a straight section of coat hanger wire. Make the tool about 8 or 9 inches long and use pliers to put a right angle bend on one end of the tool so that the foot created is about 3/4" long. You can then easily fish this tool up from the bottom of the engine and then twist it so that the "foot" can feel for the the gasket surface along that area of the engine block. This worked great and I was able to confirm that the gasket was aligned and in the groove.
I then proceeded to HAND tighten all the bolts in the pan. With (22) bolts holding the pan in place, you will quickly notice that you can actually lift the pan into place by hand tightening the bolts. You may have to run around the bolt pattern by hand 5 to 10 times, but every time you do this, the bolts are then slightly loose. Finally, the pan and gasket will be snugged up against the engine block, and hand tightening no longer works well. So, it is time to use the torque wrench and the tightening sequence noted in the shop manual to torque the bolts in two steps: the first to 3 ft-lb And the second pass (in the proper sequence) to 6 ft-lb.. Please note that (3) of the (22) pan bolts are difficult if not impossible to get to with a torque wrench. To access the single bolt that is on the front of the pan on the drivers side and is difficult to get at because of the close proximity of the A/C compressor, you can use a swivel socket on the end of a 12" extension to get to it. Since the swivel will be slightly "cocked", the torque reading will be slightly in error; but, I doubt that it will be enough to pose any problem.
Then there are (2) bolts on the passenger side of the oil pan directly above the flanged port for the oil level sensor. Since the flange bulges outward, there is insufficient room between the pan bolt head and the sensor flange to get the torque wrench in place. So, I "cheated" for those two bolts and used a box end wrench to tighten the bolts. I "calibrated" the amount of torque I put on the wrench by attempting to turn bolts that had been properly torqued and then attempting to exert the same amount of force on the two bolts that were inaccessible with the torque wrench. Again, I think that I will be ok in that area.
Finally, install the oil level sensor into the pan. You do this by installing the sensor rotated 180 degrees from its final position. This means that during install, the sensor points down to the ground. Holding it in that orientation, you can fish the sensor through the hole in the oil pan and into the area around the oil baffle. Once fully inserted, rotate the sensor back into its normal position and bolt her down. Be sure to use a new gasket when installing the sensor!
Thanks to all the previous contributors to this forum for your experiences. Hopefully, mine will help in making this "awkward" installation go smoothly.
And, man was there ever a list of issues! Having read it all and then reviewing what is written in the OEM Shop Manual and on Clarks Garage, I came to a number of conclusions about how I would do the job.
First, after cleaning up all the old parts, and before attempting to install the gasket on the pan, take the oil pan (without gasket) and play around with getting it into place on the engine. You have to lift in place while orienting it so that the oil pickup tube (and suction screen) slide into the oil baffle mounted in the bottom of the pan. Not really difficult, but you need to see how to "coax" the pan into place without disturbing the gasket.
Then there are two major issues with this gasket. The first issue apparently is a tendency for the gasket to creep out of position as the pan bolts are tightened since it is very lightly torqued. The second issue is installation cleanliness. The gasket is an elaborate geometry; but there have been issues with contamination from a residual of parting agent on the gasket remaining from its manufacture. And, since the gasket is a little bit complicated, there is a tendency for the gasket to move around during installation..
So, I attacked cleanliness first. I wiped down the rubber gasket with alcohol to remove any type of contamination. Then I wiped down the oil pan flange and the machined mating surface on the engine. I was careful to remove all remnants of the old gasket or materials that were used to hold it in place, without mechanically attempting to smooth out the mating surfaces. To do this I used a Scotchbrite pad and some acetone as a solvent. Worked great.
I also concluded that one should not attempt to sand down the mating surfaces on the pan and the engine. There is some micro roughness left by machining marks on the block. This minimal amount of roughness may be intentional and needed to hold the lightly torqued pan gasket in place.
Then I used a minimal amount of gasket adhesive ONLY in the four corners of the oil pan (as discussed both in the shop manual and on Clarks Garage). Please note that I used a gasket adhesive, and NOT a gasket sealant. I thinly spread the adhesive on the four corners of both the gasket and the mating area of the pan. When I pressed the gasket into place, it was held there by the adhesive. Also, I inserted the (4) long pan screws in the (4) corners of the pan. This helped to pin the corners of the gasket down during installation while also allowing the long bolts to be held in place so that during installation, while holding the pan in place with one hand, you would have easy access to the already inserted bolts. This also worked very well. There was enough of a misalignment between the holes in the gasket and the pan to just squeeze the bolts, thus holding them in place. If that does not work, then use a little bit of duct tape to hold the bolts into the pan (I did this with one of the four bolts).
I also followed the advice of others and tied down every other bolt hole in the gasket to the pan using dental floss. Once the pan is in place, you can cut the dental floss free with a razor blade (my choice). This worked like a champ.
Also, do not attempt to install the oil level sender in the pan until AFTER the pan has been installed since the level sender interferes with the oil pump suction pipe. Ask me how I know this!!
The bottom line is that it took me all of 20 minutes to prep the engine and pan and to trial fit the pan. Once I found the angles needed to slip the pan into place, I installed the gasket on the pan and aligned the pan and then slid it into place. Once installed, I was able to hand thread the four corner bolts and then the remaining bolts into place while removing the dental floss with a razor blade.
One concern that I had was that the gasket "arch" on both ends of the gasket slide in the grooves on the engine block as the pan is put into place. You want to visually confirm this. While visual confirmation is possible at the front of the oil pan, you can not see up into the area on the rear of the oil pan once the pan is slid into place. In fact, there is a gap between the rear of the oil pan and the flywheel housing that is only about 3/8"wide, so you really can't even get a finger up into the area to "feel" that the gasket is evenly inserted into the groove. I tried getting a mirror up in the area to see, but that was not possible either. So, to confirm that the gasket was laid into the groove evenly, I made a tool out of a straight section of coat hanger wire. Make the tool about 8 or 9 inches long and use pliers to put a right angle bend on one end of the tool so that the foot created is about 3/4" long. You can then easily fish this tool up from the bottom of the engine and then twist it so that the "foot" can feel for the the gasket surface along that area of the engine block. This worked great and I was able to confirm that the gasket was aligned and in the groove.
I then proceeded to HAND tighten all the bolts in the pan. With (22) bolts holding the pan in place, you will quickly notice that you can actually lift the pan into place by hand tightening the bolts. You may have to run around the bolt pattern by hand 5 to 10 times, but every time you do this, the bolts are then slightly loose. Finally, the pan and gasket will be snugged up against the engine block, and hand tightening no longer works well. So, it is time to use the torque wrench and the tightening sequence noted in the shop manual to torque the bolts in two steps: the first to 3 ft-lb And the second pass (in the proper sequence) to 6 ft-lb.. Please note that (3) of the (22) pan bolts are difficult if not impossible to get to with a torque wrench. To access the single bolt that is on the front of the pan on the drivers side and is difficult to get at because of the close proximity of the A/C compressor, you can use a swivel socket on the end of a 12" extension to get to it. Since the swivel will be slightly "cocked", the torque reading will be slightly in error; but, I doubt that it will be enough to pose any problem.
Then there are (2) bolts on the passenger side of the oil pan directly above the flanged port for the oil level sensor. Since the flange bulges outward, there is insufficient room between the pan bolt head and the sensor flange to get the torque wrench in place. So, I "cheated" for those two bolts and used a box end wrench to tighten the bolts. I "calibrated" the amount of torque I put on the wrench by attempting to turn bolts that had been properly torqued and then attempting to exert the same amount of force on the two bolts that were inaccessible with the torque wrench. Again, I think that I will be ok in that area.
Finally, install the oil level sensor into the pan. You do this by installing the sensor rotated 180 degrees from its final position. This means that during install, the sensor points down to the ground. Holding it in that orientation, you can fish the sensor through the hole in the oil pan and into the area around the oil baffle. Once fully inserted, rotate the sensor back into its normal position and bolt her down. Be sure to use a new gasket when installing the sensor!
Thanks to all the previous contributors to this forum for your experiences. Hopefully, mine will help in making this "awkward" installation go smoothly.
Last edited by earossi; 07-05-2011 at 11:44 PM.
12-15-2020, 12:31 PM
#4
excellent write-up indeed
